CHAPTER 11
Erection Disorders

Despite the current rhetoric. . . . about sex and intimacy’s involving more than penile-vaginal intercourse,

the quest for a rigid erection appears to dominate both popular and professional interest. Moreover,

it seems likely that our diligence in finding new ways for overcoming erectile difficulties serves

unwittingly to reinforce the male myth that rock-hard, ever-available phalluses are a necessary component

of male identity. This is indeed a dilemma.

Rosen and Leiblum, 19921

 

General Considerations

The Problem

A 49-year-old widower described erection difficulties for the past year. His 25-year

marriage was loving and harmonious throughout but sexual activity stopped after

his wife was diagnosed with ovarian cancer six years before her death. Their sexual

relationship during the period of her illness had been meager as a result of her lack

of sexual desire. Although he missed her greatly, he felt lonely since her death

three years before and, somewhat reluctantly at first, began dating other women. A

resumption of sexual activity soon resulted but much to his chagrin he found that

in contrast to when he would awaken in the morning or masturbate, his erections

with women partners were much less firm. He felt considerable tension, particularly

because some months before, he had developed a strong attachment to one

woman in particular and was fearful that the relationship would soon end because

of his sexual troubles. As he discussed his grief over the loss of his wife and talked

about his guilt over his intimacy with another woman, his erectile problems began

to diminish.

 

A 67-year-old man, married for 39 years, and having a history of angina prior to a

coronary by-pass operation three years before was referred to a “sex clinic” together

with his wife because of his erectile difficulties. Sexual experiences had been enjoyable

and uncomplicated for both until he developed angina at the age of 62.

Orgasm provoked his chest pain. Nitroglycerin was prescribed but he used it only

occasionally because it resulted in headache. His angina during sexual activity was

frightening to his wife who, nevertheless, recognized the importance of sexual

experiences in his life and supported his desire to continue being sexually active.

Cardiac surgery resulted in the disappearance of his chest pain. However, some

months before his operation, he began to experience difficulty becoming fully

erect at any time, and would frequently lose whatever fullness he had before vaginal

entry occurred. His erectile difficulties with his wife had become persistent

and when questioned, it was apparent that his morning erections were not different.

Sildenafil (Viagra) was dismissed as a treatment possibility because of his occasional

use of nitroglycerin. He was referred to a urologist for intracavernosal injections.

 

Terminology

The phrase “erectile dysfunction” has provided competition for the more popular word

“impotence.” The latter has a tenacity for usage that does not exist for the female

equivalent and now rarely-seen word, “frigidity.” Both words have similar deficiencies:

they are so broad in usage they (1) incorporate disorders of desire and function and

(2) imply something pejorative about the patient’s personality quite apart from their

sexual expression.2

The social confusion surrounding the word “impotence” is, perhaps, exemplified by

the first recommendation of the National Institutes of Health Consensus Statement on

Impotence, which was to change the term impotence to erectile dysfunction as a way of

characterizing “the inability to attain and/or maintain penile erection sufficient for satisfactory

sexual performance.”3 (Interestingly, no conference was necessary to change

usage of the word “frigidity”).

 

Mechanism of Erection

The fundamental element in the development of an erection is the trapping of blood

in the penis. The mechanism by which this occurs was described by Lue and Tanagho

(Figure 11-1). A human penis has three cylinders: Paired corpora cavernosa (CC) on

the dorsal surface, and the completely separate corpus spongiosum (CS), which carries

the urethra and is responsible for the ventral bulge.

The CS anatomically includes the glans of the penis. The CC are each surrounded

by an inflexible envelope of fibrous tissue: the tunica albuginea (TA). The CS has a

much thinner TA and is connected to the glans, which has almost none.

Blood is carried to the penis by the two internal pudendal arteries

and within the penis by paired cavernosal arteries. The latter subsequently

divide into smaller vessels (arterioles), which are surrounded

by smooth muscle. The same can be said of the helicine arteries (small

spiral shaped arteries). In the CC and CS, blood is then carried to

interconnecting sinusoids (microlakes, which have the appearance of a

sponge when filled but are mostly collapsed when a penis is flaccid),

which are also surrounded by smooth muscle. Small veins (venules)

carry blood away to the emissary veins, which in turn pierce the TA.

As an erection develops, there is relaxation of the smooth muscle

around the arterial tree and walls of the sinusoids, increasing the inflow

 

 

of blood into the penis and allowing more blood to remain. While expansion occurs,

the venules are compressed between the sinusoids and TA, thereby stopping the outflow

and in effect trapping blood in the sinusoids of the penis. “The smooth muscles

in the arteriolar wall and trabeculae surrounding the sinusoids are the controlling

mechanism of penile erection.”4

(Biochemical aspects of erection are discussed in the treatment section of “ Generalized

Erectile Dysfunction: Organic, Mixed, or Undetermined Origin” below in this

chapter).

 

Definition

The main difficulty with the definition of erectile dysfunction is whether the diagnosis

of erectile problems should refer only to the hardness or softness of a man’s erection

or if it should also include a behavioral component. For example, should a man

who has erections that are persistently partial but whose penis is sufficiently enlarged

to regularly engage in intercourse be designated as having an “erectile disorder?” If

that same man designates himself as “impotent,” what should be the diagnostic position

of the health professional? Should there be a subjective component to an erectile

disorder: does it make any difference what the man (or his partner) thinks? Is the

fullness of a man’s penis in intercourse all that matters? Is intercourse the only sexual

activity on which the definition is based? What about erections with other sexual

practices? These, and other questions, are not intellectual exercises but daily clinical

quandaries.

 

Classification

DSM-IV-PC summarized the criteria for the diagnosis of “Male Erectile

Disorder” as follows: “persistent or recurrent inability to attain, or to

maintain until completion of the sexual activity, an adequate erection,

causing marked distress or interpersonal difficulty”5(p. 116). The clinician

is further instructed to “especially consider problems due to a general

medical condition . . . such as diabetes or vascular disease, and

problems due to substance use . . . such as alcohol and prescription

medication. Erectile dysfunction in all situations, as well as lack of nocturnal erections, strongly suggests

that a general medical condition or substance use is the cause”(italics added).

The subclassification of Erectile Disorders used in this chapter is summarized in

Figure 11-2.

 

Epidemiology

The Massachusetts Male Aging Study (MMAS) provided revealing information about

erectile function, dysfunction, and “potency” in middle-aged and older men.6 The

study was conducted in the late 80s, was concerned with health and aging in men, was

community-based, and involved a random sample of noninstitutionalized men 40 to 70

years old. Individuals who completed a self-administered questionnaire on sexual function

and activity included 1290 (75%) of the 1709 MMAS subjects. “Potency” was

subjective in that it was defined by those who completed the questionnaires. Defined

as “satisfactory functional capacity for erection,” “potency” could “coexist with some

 

degree of erectile dysfunction in the sense of submaximal rigidity or submaximal capability

to sustain the erection.” Four degrees of “impotence” were described:

• None

• Minimal

• Moderate

• Complete

The overall prevalence of impotence in this study was found to be

52%, with 15% defined as minimal, 25% moderate, and 10% complete.

Prevalence was highly related to age with the probability of moderate

impotence doubling from 17% to 34% and complete impotence tripling

from 5% to 15% between subject ages 40 to 70 years. Looking at

this from the opposite perspective, 60% of men were not impotent at

age 40 years, compared to 33% not impotent at age 70 years.

The frequency of erectile problems found in health care settings seems to depend

somewhat on the clinical context. That is, different percentages can be found in

various clinical settings: medical outpatients, urology, and sex therapy7 (p. 11). In a

review of the frequency of sexual problems presented to “sex clinics” between the

mid-70s to 1990, 36% to 53% of men complained of “male erectile disorder.”8 Masters

and Johnson subcategorized this diagnosis into “primary” and “secondary”.9 The

former referred to a man who had never had intercourse (p. 137), and the latter

referred to a man who had been able to have intercourse at least once in the past

 

 

(p.157). Of all the men with “impotence” who consulted Masters & Johnson, 13%

had the primary form (p. 367).

 

Etiology

“Repeatedly bandied about is the hackneyed declaration that in the 1970s, mental

health professionals pronounced 90% of impotence to be psychogenic; more recently

urologists proclaim that 90% of impotence is organic. Both sides are wrong, not just

for the disrespectful attitudes toward one another, but for failing to develop more

sophisticated notions of etiology.”10

LoPiccolo saw clinical limitations to the either/or approach and suggested an

alternative way of thinking about the etiology of erectile dysfunctions: that organic

and psychogenic factors be viewed as two “separate and independently varying

dimensions” and that both should be examined in each instance.11 To support this

position, he reported on 63 men with erectile difficulties who were carefully and

thoroughly investigated in both areas. Ten men were found to have a purely psychogenic

etiology, and three men were found to have a purely organic etiology.

The majority of men in this study (50/63) displayed a mixture of factors, indicating

that a “two-category typology was . . . inappropriate.” Furthermore, almost

one third of the men (19/63) had “mild organic impairments” but “significant psychological

problems.” These men might have been considered “organic” in a twopart

etiological scheme, however, they might also have been sufficiently responsive

to psychological intervention such that physical treatment may not have been necessary.

In a diagnostic and a therapeutic sense, the implication of LoPiccolo’s approach is

quite serious. It means that even if a factor that is of potential etiological significance is

found (biological or psychological), it is not necessarily the factor. Or, in other words,

“the detection of some possible etiological factor . . . does not mean that the

cause . . . has been fully explained. Such a factor may even be coincidental, of no

(actual) etiological significance.”12

The possible nature of the interrelationship between biological and psychological

factors was suggested as the following: “When any one (organic factor) occurs in isolation,

it may serve to make erections more vulnerable to emotional disturbances and

sympathetic overactivity, facilitating the vicious circle of performance anxiety that

maintains ED.”12

 

Investigation

History

History-taking is an indispensable element in the investigation of erectile disorders

and provides direction for further exploration and treatment. Issues to inquire about

and questions to ask include:

1. Duration (see Chapter 4, “lifelong versus acquired”)

Suggested Question: “Have you always had difficulties with erections

or is this a relatively new problem?”

2. Partner-related erections (see Chapter 4, “generalized” versus “situational”)

Suggested Question: “What are your erections like when you are

with your wife (partner)?”

3. Sleep [including morning] erections (see Chapter 4, “generalized versus situational”)

Suggested Question: “What are your erections like when you

wake up in the morning?”

Additional Question: “Do you wake up at night for any reason?”

Additional Question if the Answer is Yes: “What are your erections like

when you wake up at night?”

(Comment: the assessment value of asking about sleep-related erections is generally

recognized but not universally accepted.13 When full sleep-related erections exist, the

information seems highly useful from a diagnostic viewpoint. However, partial or nonexistent

sleep erections are not necessarily meaningful since this situation may coexist

with daytime erections firm enough for intercourse.)

4. Masturbation erections (see Chapter 4, “generalized versus situational”)

Suggested Question: “What are your erections like when you stimulate

yourself (or masturbate)?”

5. Fullness of erections (see Chapter 4, “description”)

Suggested Question: “On a scale of zero to ten where zero is

entirely soft and ten is fully hard and stiff, what are your

erections like when you are with your wife (partner)?”

Additional Question: “Using the same scale, What are your erections

like when you wake up in the morning?”

Additional Question: “If you wake up during the night, using the

same scale, what are your erections like at that time?”

Additional Question: “using the same scale, What are your erections

like with self-stimulation or masturbation?”

Additional Question Under All Three Circumstances: “About how long do

your erections LAST?”

(Comment: Even though erections may be full under all three circumstances, the duration

of erections may be important. Erections may consistently be short-lived—a matter

of diagnostic significance, since that observation may indicate a “venous leak”).13

6. Psychological accompaniment (see Chapter 4, “patient and partner’s reaction to

problem”)

Suggested Question: “When you have trouble with your erection,

what’s going through your mind?”

Additional Question: “What does your wife (partner) say

at these times?”

 

Physical Examination

In men with erectile difficulties, physical examination is essential even

if the “yield is low.”12 “Without it many patients feel that they have not

been properly assessed or taken seriously and they may refuse a psychogenic

diagnosis as a result”.12 The physical examination concentrates

particularly on the endocrine, vascular and neurologic systems,

as well as local genital factors.

Signs of hormonal abnormalities include the following14 (p. 85):

1. Testicular atrophy

2. Gynecomastia

3. Galactorrhea

4. Visual field abnormalities

5. Sparse body hair

6. Decreased beard growth

7. Skin hyperpigmentation

8. Signs of thyroid abnormalities

9. Low energy level and lack of “well-being”

Signs of vascular disease include the following14 (p.91):

1. Weak pulses in legs or ankles

2. Hair loss on lower legs

3. Unusually cool temperature of penis or lower legs

4. High lipid levels

5. High cholesterol levels

6. Duputyren’s contractures [Peyronie’s disease only]

7. Fibrosis of outer ear cartilage [Peyronie’s disease only]

Signs that indicate neurological factors include the following14 (p. 93):

1. Weak or absent genital reflexes (bulbocavernosus, cremasteric, scrotal, internal

anal, and superficial anal)

In men with erectile difficulties, physical

examination is essential even if the

“yield is low.”12 Many patients feel that

they have not been properly assessed or

taken seriously if there is no physical

examination, and they may refuse a

psychogenic diagnosis as a result.12

2. Neurological abnormalities in the S2 to S4 nerve root distribution

3. Reduced penile sensory thresholds to light touch electrical stimulation or

vibration

An investigation conducted in a medical outpatient clinic found that the physical

examination rarely helped to differentiate various etiological factors with two exceptions15:

• Small testes in patients with primary hypogonadism

• Peripheral neuropathy in patients with diabetes

 

Laboratory Investigation

The extent of a clinician’s use of the laboratory in the investigation of erectile dysfunction

depends on the results of the history and physical examination (see “Investigation”

below in this Chapter in the sections on “Situational [‘psychogenic’] Erectile Dysfunction”

and “Generalized Erectile Dysfunction: Organic, Mixed, or Undetermined Origin.”

 

Treatment

As LoPiccolo has shown, psychological and physiological factors are

present in the vast majority of men with an erectile disorder.11 “Psychological”

factors include social, cultural, religious, and interpersonal

elements, and those within the person. Since all sexual behavior of men

is influenced to a great degree by these issues, it is reasonable to

assume that these factors are present in the context of erectile difficulties

as well. The logical result of LoPiccolo’s research is the concept

that regardless of the etiology of a man’s erectile difficulties, a health care clinician

must always attend to universally concomitant psychological issues. That is:

“Given the critical role of psychological factors, even in cases with clearcut organic

etiology, the failure to attend to psychological issues is indefensible (italics added). The potential

impact of erectile difficulties on mood state, self-esteem and self-efficacy, as well as on

the couple’s relationship cannot be overemphasized.”16

 

Situational (“Psychogenic”) Erectile Dysfunction

The assessment of situational erectile disorders is summarized in Figure 11-3.

 

Description

Lifelong (“Primary”) Erectile Disorders

In this unusual syndrome, the man reveals that all, or most, attempts at intercourse

result in diminution of his erection before attempts at vaginal entry. Levine reasonably

suggested that the definition of the disorder be “liberalized” to include men who

gain vaginal entry “occasionally”17 (p. 208), Typically, the man has no difficulty

obtaining full erections when alone, with masturbation, or when awakening. Ejaculation

and orgasm have been similarly unimpaired. The sexual desire phase may have

been problematic if thoughts associated with sexual arousal were atypical (as is

Failure to attend to psychological issues

is indefensible. The potential effect of

erectile difficulties on mood state, selfesteem,

and self-efficacy (as well as the

couple’s relationship) cannot be overemphasized.16

 

 

often the case), such as fantasies related to paraphilias. Since behavior connected to

such fantasies is often easier to carry out alone, such men tend to avoid intimate

relationships and may depend on prostitutes (with whom they can be more candid)

for partner-related sexual experiences. Even then, intercourse rarely, if ever, occurs.

Pressure from a (non-prostitute) partner may be a major factor in seeking treatment.

When this occurs, the patient may not be particularly forthcoming about his thoughts

and feelings.

 

A 32-year-old man was seen with his 29-year-old wife. They were married for two

years and despite being sexually active with one another several times each week,

intercourse never occurred. (They previously agreed not to engage in intercourse

before they married.) She was aware of the fact that he had never experienced

intercourse in the past. His erection predictably diminished whenever he moved

close to her vagina. She wanted to become pregnant and felt the “biological clock

ticking.”

Her desire for pregnancy and her love for her husband resulted in a singleminded

pursuit of her attempts at solving their sexual difficulties. He was less

enthusiastic. Attempts at psychotherapy with him alone and sex therapy as a

couple proved unhelpful. Since he was a shy person and spontaneously revealed

little about himself, he never previously told anyone about having been repeatedly

sexually assaulted as a child by his mother. Nor had he ever discussed his

current sexual fantasies (about which he was quite ashamed) that involved the

insertion of a knife into a woman’s vagina. He was again referred for individual

psychotherapy and accepted the need for candor with his therapist concerning

his sexual experiences as a child and his current sexual thoughts and feelings.

 

Acquired (“Secondary”) Erectile Disorders

In contrast to the lifelong form of situational erectile dysfunction, the patient

reports having had intercourse in the past, perhaps on many occasions for many

years. However in the present, full erections might occur with his partner before

clothes are removed but the fullness may diminish after he reaches the bed or

after the commencement of sexual activity. Intercourse might occur sometimes but

this seems unpredictable. Characteristically, he never had a problem obtaining full

erections after a period of sleep and with masturbation and, as well, describes no

difficulty with ejaculation and orgasm now or in the past. History reveals that

when younger, he frequently had erection troubles with partners on the first few

occasions when sexual intercourse was attempted. However, when in a long-term

relationship, he functioned well sexually although erectile difficulties occasionally

reappeared at times of “stress.” After a relationship of many years, doubts about

his sexual “performance” developed. There may have been a marked diminution of

sexual activity in spite of his partner’s attempts at reassurance. She believed him

not to be sexually interested, and wondered about her own attractiveness to him.

Questioning revealed that his apparent sexual disinterest is actually avoidance. He

remains privately interested but feels that he is not “a man” anymore with his

wife.

 

A 51-year-old rather shy man was seen together with his 49-year-old outspoken

wife. They were married for 23 years. Sexual activity had never been a problem

until about five years ago when his erections sometimes became soft after vaginal

entry, so much so that intercourse could not continue. This sequence of events,

and erectile loss even before intromission, gradually occurred more often and

culminated in the complete lack of intercourse in the previous six months. His

sexual desire, while never as strong as that of his wife, had not changed and he

would masturbate (without erectile problem) and ejaculate about once or twice

each month. He thought that the origin of his erection troubles were mainly

related to his age but he also wondered if his substantial use of alcohol for the

previous 25 years was also a factor. His heavy drinking stopped completely about

five years ago when he joined AA. This was about the same time that his erection

problems began. After discussion of possible etiological factors, he understood

that much of his erectile difficulty was connected to his feelings about his wife.

They were referred to a treatment program that focused on both their marriage

and their sexual relationship.

 

Etiology

Lifelong (“Primary”) Erectile Dysfunction

This syndrome is “often, though not invariably, associated with a diagnosable major

[psychiatric] condition”18 (p. 133). Masters and Johnson described a group of 31

men with “Primary Impotence,” eleven of whom were in unconsummated marriages9

(pp. 137-156). Factors they considered to be of etiological significance were multiple

and included the following:

1. Homoerotic desire

2. Mother/son incest

3. Strict religious orthodoxy

4. Psychologically damaging attempts at first intercourse with a prostitute (sometimes

associated with drugs or alcohol)

Other investigators also reported associated paraphilias and gender

identity disorders18 (pp. 133-135);19 (p. 245).

 

Acquired (“Secondary”) Erectile Dysfunction

Most men with a clearly situational erectile dysfunction also indicate

that it is acquired.

In almost all such men, the etiology involves some combination of

factors17(p. 200) in the following three areas:

1. Performance anxiety

 

2. Antecedent life events

3. Developmental vulnerabilities

The “phase of time” for each of these three is, respectively, here-andnow

lovemaking, months to years (“recent” history), and childhood/

adolescence (“remote” history).

A major here-and-now issue is “performance anxiety,” a concept

introduced by Masters and Johnson to describe the worry that a patient

may have about his or her sexual function and whether it will be similarly

impaired on a current occasion as it was at a previous time.9 Performance

anxiety is partner related and probably universal in men with

erectile difficulties. From a primary care perspective, performance anxiety

is an important target of the treatment of “psychogenic impotence”

in both solo men and couples. However, this component explains only

part of the etiology of this syndrome, since eliminating performance

anxiety does not always result in cure.

Antecedent life events and developmental vulnerabilities may be of

therapeutic significance also, but they are difficult to consider in detail

in a primary care setting.

The former “typically fall into one of five categories”17 (p.202):

1. Deterioration in the nonsexual relationship with a spouse or

partner

2. Divorce

3. Death of a spouse

4. Vocational failure

5. Loss of health

Developmental vulnerabilities include such issues as child sexual abuse and impairments

in sexual identity.17

On a clinical level, one frequently has the impression of a link between psychogenic

erection difficulties and difficulty with expression of anger. In the MMAS study,

the suppression and expression of anger was assessed. “Men with maximum levels of

anger suppression and anger expression showed an age-adjusted probability of 35%

for moderate impotence and 16% to 19% for complete impotence, both well above

the general level (9.6%).”6 The MMAS study did not subcategorize men with “impotence”

according to whether the origin was “psychogenic,” “organic,” mixed,” or

“undetermined.” It may certainly be possible that problems with anger may also

potentiate some of the etiological factors associated with erectile difficulties of

organic, mixed or undetermined origin discussed below.

 

Laboratory Investigation

If in instances where the man reports being otherwise healthy, the history clearly

indicates the situational nature of the man’s erectile dysfunction, there is no sign of

any contributory physical abnormality, and there are no other sexual symptoms (such

as lack of sexual desire), little needs to be done to obtain additional specific laboratory

data.

 

Treatment

“It is fortunate for many psychologically impotent men that a complete

understanding of the causes is not necessary. Some men spontaneously

get over their problem within a short period of time without

any therapy”17 (p. 202). For those whose problem is not solved,

an approach is proposed that concentrates on five themes that have

been identified in a review of the literature (Box 11-1).16 Most

importantly for generalist health professionals, some of these five

themes listed in Box 11-1 can be easily integrated into primary

care.

The first theme is accurate information and realistic ideas and expectations regarding

sexual performance and satisfaction—all of which is a problem in many

men with erectile difficulties (and their women partners).

Areas to be addressed include:

1. Genital anatomy and physiology

2. The sex response cycle

3. Masturbation

4. Male-female differences in sexual response

5. Effect of aging, illness, and medication on sexual desire, arousal, and

orgasm

Comprehensive, inexpensive, and up-to-date self-help books are easilly

vailable and can be used as an adjunct in this education process.20 The

provision of information can correct unrealistic ideas and expectations—

thoughts that could, themselves, significantly interfere with erectile function.

For example, the “gold standard” of erectile function for many men is what occurred in

their teenage years. The folly of “living in the past” becomes evident to a man in his

(for example) 40s when he is asked to provide another example of a part of his body

that functions in the present as it did when he was a teenager. In addition, it could be

pointed out to him that he is, in effect, basing his sexual expectations for his 60 years

of adult sexual function (approximate life expectancy minus 15 years of pre- and early

 

 

adolescence) on the five (or so) years of erectile experience as a teen! Other examples

of ideas and expectations that might be discussed with a patient include his thoughts

when he or his partner is initiating sexual activity and when his penis is becoming

firmer or softer.

Yet another example of the therapeutic value of information is that of the sexual

changes associated with aging. The educational effect on the treatment of erectile

dysfunction was studied in a group of heterosexual couples between the ages of 55 and

75.21 Investigators found that a four-hour workshop resulted in increased knowledge,

especially about the normal changes that occur with age, thereby allowing participants

to have more realistic expectations of themselves and their partners. Sexual satisfaction

also increased despite the presence of associated organic factors.

The second theme is the relief of “performance anxiety.” Diminishing or eliminating this

frequently appearing factor involves inducing sexual response in the man (in this

instance, erection) while he paradoxically avoids sexual invitations for intercourse.

Masters and Johnson described this approach to the treatment of performance anxiety9

(pp. 193-213). The method involves couple oriented touching “exercises” and

concentrates on sensate focus, a term they coined (pp. 71-75) to denote a focus on

immediate sensation rather than sexual goals of, for example, intercourse. Briefly, the

exercises occur in stages and initially exclude intercourse and touching of breasts (in

the woman) and genitalia, then include touching of the previously barred areas (while

maintaining the exclusion of intercourse), and finally include unrestricted touching

and intercourse. Couples do not move to the next level of the exercise until the previous

one is mastered. While requiring repeated visits, this technique

is not complex and might, therefore, be within the boundaries of primary

care (depending on the clinician’s time, comfort, and interest

and the availability of specialists to whom one could refer).

One major (and often unappreciated) objective of “sensate focus” in

the treatment of erectile dysfunction is change in the communication

pattern between partners so they could, with “permission” (i.e., encouragement),

and with a minimum of tension and embarrassment, tell one

another what is, and is not, pleasurable. (Rather than the communication exercise it is,

sensate focus is sometimes mistakenly thought of as a way of allowing one to discover

previously unappreciated physical feelings in particular body areas.) A second objective

of “sensate focus” is to remove the demand for intercourse. Since the man does not

“need” an erection for any purpose other than intercourse and intercourse is not to take

place, theoretically the “pressure” on the man to “perform” will be removed and the

worry (which is thought to inhibit his erection) will disappear, thus allowing his erection

to develop unhindered.

Two obstacles to sensate focus have been described11 (p. 189). First, the passive

process of sensate focus is contrary to the need of aging men for

active and direct penile stimulation for an erection to develop. Second,

the idea of performance anxiety is so popular that general knowledge

of the concept has rendered its treatment less effective. Consequently,

LoPiccolo coined the term metaperformance anxiety to explain

 

why, on some occasions, “eliminating performance anxiety does not lead to erection

during sensate focus body massage”11 (p. 189).

Recently the role of “anxiety” in producing erectile troubles and the expected relief

with its disappearance has been reexamined and reviewed from a research rather than

clinical viewpoint.22 Functional and dysfunctional men have been shown to respond

differently to anxiety. The results of these studies are summarized as follows:

1. Functional men can become aroused on demand, whereas the same request in

dysfunctional men results in interference with the arousal process (similar results

were found in laboratory studies)

2. Functional men report their subjective arousal to be greater than dysfunctional

men regardless of what occurs physically

3. (Particularly interesting from a therapeutic viewpoint) functional

men report distraction to be an obstacle to sexual response, whereas

this is neutral or actually helpful to dysfunctional men16

The third theme concentrates on sexual “script” modification (i.e., changes to

what actually occurs sexually between two people). The fourth theme concentrates on relationship

issues such as intimacy, control, conflict resolution, and trust. The fifth theme concentrates

on the prevention of relapse. Since the third, fourth, and fifth areas are often more

within the interests, practice pattern, and skills of the sex therapist, they are not discussed

at length here.

Little published information exists on the treatment of situational erectile dysfunction

by methods usually reserved for occasions when the etiology is “organic, mixed,

or undetermined” (see below in the chapter). Few quarrel with the concept of considering

such an approach when psychologically-oriented methods have been unsuccessful.

However, when medical techniques are used early in the course of treatment, the concept

is more problematic. The rationale sometimes given is one of providing the man

an opportunity to have a erection in worry free circumstances as a way of overcoming

an undefined obstacle. The rationale continues that after the man

engages in successful sexual experiences that require an erection he will

be able to do so without extra support.

A study of the use of intracavernosal injections in 15 men with “psychogenic

impotence” did not convey a sense of optimism about the

outcome of such an approach.23 The authors concluded that performance

anxiety was not alleviated, that dependence on injections for

intercourse remained, and that the capacity for intimacy did not

improve. One can well imagine that the consequences (benefits and

disappointments) of the use of such treatments for men with situational

erectile difficulties become magnified when men who have these problems

ask for, and are given, an oral medication such as sildenafil (see below in the

chapter).

Few long-term follow-up studies have been conducted on the treatment of erectile

dysfunction. Results for “primary” and “secondary” (i.e., acquired) erectile dysfunction

were reported by Masters and Johnson as an “overall failure rate” (OFR)

and were based on personal interviews conducted five years after the patients were

 

originally treated9 (p. 367). The OFR for “primary impotence” was 41%. This modest

improvement supports the clinical experience of greater complexity in the treatment

of this form of the erectile dysfunction syndrome. Furthermore, it suggests

that insofar as “primary” impotence is concerned, a focus on performance anxiety

without considering other factors will likely result in quite limited gains.

The OFR reported by Masters and Johnson for the “secondary” form was 31%.9

Another follow-up study in the United States, carefully conducted after three years,

found that of the 18 men presenting with “difficulty achieving or maintaining erection,”

ten maintained the improvement, four were the same, and three were worse.24

The authors found that there was “significant improvement maintained across time in

erectile capability during intercourse . . . . improved satisfaction in the sexual relationship

. . . [and] . . . longer duration of foreplay.” Hawton and his colleagues

conducted a rigorous one to six year follow-up study in the United Kingdom and

found that the “gains made during therapy by couples who presented with erectile

dysfunction were reasonably well sustained.”25 Of the 18 couples who undertook treatment,

14 reported the problem resolved or mostly so at the end of therapy, and 11

reported the same at follow-up.

 

Indications for Referral for Consultation or Continuing Care by a Specialist

1. Since the “primary” form of situational erectile disorders is so often associated

with complex individual diagnosable psychiatric conditions rather than interpersonal

conflicts, referral to a mental health professional for individual treatment is

usually the most reasonable course of action19 (p. 245). If the health professional

is not also a sex-specialist, it may be useful to consult with one before proceeding

with the referral.

2. Solo men with the “secondary” form of situational erectile dysfunction (i.e.,

those without a partner, with an uncommitted partner, in a relationship that is

filled with so much discord that they are unable to cooperate with each other, or

who have been raised in a culture in which men are clearly in control and women

entirely submissive) often require an amalgam of traditional psychotherapy and

sex therapy. Such men are candidates for individual care with a sex-specialist

who is also a mental health professional.

3. Couples in which the man has the “secondary” form of situational erectile dysfunction

and who would benefit by a here-and-now focus on information and

performance anxiety (previously described in the treatment of situational problems

in this chapter) could be cared for in primary care. Couples who do not

respond to this approach may require an additional focus on two of the other

elements: “script” modification and attention to relationship conflicts. Given the

time and experience involved in providing these other components, referral

would be reasonable in these circumstances. If referral does take place, the health

professional should be a sex-specialist who also has clinical experience in the

mental health area.

4. Consultation with a sex-specialist is warrented when consideration is given to

providing a form of treatment usually reserved for men with erectile dysfunction

of “organic, mixed, or undetermined origin.” The purpose would be to examine

the possibility of integrating biological and psychologically oriented treatment

methods.

 

Generalized Erectile Dysfunction: Organic, Mixed, or UnDetermined Origin

The assessment of generalized erectile disorders is summarized in Figure

11-4.

 

Description

The key differentiating feature of the acquired and generalized form of

erectile dysfunction is that the difficulty experienced by the man exists

in all major circumstances when he would be expected to have an erection:

with a partner, masturbation, and with sleep (including the time

when he awakens in the morning). In addition, he describes little or no

difficulty with erectile function in the past. Typically in his 50s or

older, his erection problems began in recent years. Sexual desire is usually

present but, depending on the status of his health and the nature of any previous

health troubles, there may have been problems with ejaculation or orgasm. Relationship

conflict was not apparent except as a possible result of reluctance to seek help

despite his partner’s encouragement. Although unhappy, he is not clinically

depressed.

 

A couple in their mid-60s were seen because of the man’s erectile difficulties. They

were married for seven years, both for the second time. Five years before, he held

an executive position in a major computer software company but as a result of

“downsizing” lost his job and subsequently retired. His wife had always been in

good health but he had a “mild” heart attack about three years before. He felt well

since then, stopped smoking, and was not taking any medications. On his last

medical visit several months earlier, he talked with his physician about erection

troubles, which had begun about one year before. Further history-taking revealed

that the fullness of his erections during sexual activity with his wife (as well as in

the morning and with masturbation—which occurred once every few months) had

become consistently about 50% of what he had previously experienced. The last

time he could recall having a full erection at any time was about one year earlier.

He was referred to a urologist and after a thorough investigation he was told that

the reason for his trouble was “organic.” Intracavernosal injections were suggested.

He was reluctant to pursue this option and wanted a second opinion from a sex

therapist. This consultation primarily confirmed the opinion of the urologist and as

a result he began injection treatment. He changed to sildenafil (Viagra) when this

became available and after three months of use, he and his wife reported that they

were pleased with the results.

Etiology/Risk Factors

Many medical disorders are identified as “organic causes” of erection difficulties (see

Box 11-2), however, only a few seem to account for a great many cases where the

etiology is known. Major etiological factors are discussed below.

In the Massachusetts Male Aging Study, health status was ascertained by asking if

diabetes, heart disease, and hypertension were present.6 These three “were significantly

associated with changes in the impotence probability pattern.” After

adjusting for age, 28% of men with treated diabetes, 39% of men with

treated heart disease, and 15% of those with treated hypertension were

described as having “complete impotence.”

 

Diabetes

Estimates of the prevalence of erection problems in men with diabetes

range from 27% to 71%.26 As many as 50% of people with type 2

diabetes remain undiagnosed (about 8 million people in the United

States), a serious situation since hyperglycemia in this condition

causes microvascular disease and may contribute or cause macrovascular

disease.27 Erection problems may well be a manifestation of microand/

or macrovascular disease. In the MMAS sample, “the age-adjusted

probability of complete impotence was three times greater in subjects

reporting treated diabetes than in those without diabetes.”6 In an attempt to clarify

the connection between diabetes and erection problems and to eliminate the confounding

effects of associated illness and medications, 40 men with diabetes (but free

of other illness or drugs apart from antidiabetic medication) were compared to an

equivalent group of age-matched healthy controls.26 The men with diabetes were

found to have a wide variety of sex-related difficulties, including:

1. Erectile dsyfunction with attempts at intercourse, during sleep, and with masturbation

2. Sexual desire disorders

3. Diminished frequency of intercourse

4. Premature ejaculation

5. Diminished sexual satisfaction

In another study, sexually functional men with diabetes were shown to have significantly

diminished Nocturnal Penile Tumescence (NPT) profiles when compared to a similar

control group.28

 

Cardiovascular Disorders

The association between erectile difficulties and cardiovascular disorders is well studied.

“Vascular disorders” include two groups: arterial (i.e., obstruction to the penile

inflow tract) and veno-occlusive (i.e., the inability to trap blood in the corpus cavernosum).

29 The former has attracted particular attention.

The presence of four arterial risk factors (ARF) (diabetes, smoking, hyperlipidemia,

and hypertension) was assessed in 440 “impotent” men.30 The frequency of “organic

 

impotence” occurred in 49% of men without any ARF, and 100% when there were

three or four risk factors.

 

Cigarette Smoking

The link between cigarette smoking and arterial disease is well established.

Smoking was found to be significantly more prevalent in men

who were “impotent” compared to estimates of smoking among men in

the general population.31 In one study, two groups of men with and

without penile arterial disease were compared, and the former was found

to have smoked more pack-years.32 In the MMAS, “complete impotence”

was higher in current smokers (versus current nonsmokers) who were also treated

for heart disease, hypertension, or arthritis, and, as well, in those taking cardiac drugs,

antihypertensives, or vasodilators.6 In subjects with treated heart disease the probability

of “complete impotence” in the MMAS was 56% for current smokers compared to 21%

for current nonsmokers. Likewise, treated hypertension together with smoking increased

the probability of “complete impotence” to 20% of those who had both

factors, as compared to 9% among hypertensive men who did not

smoke. Apart from particular connections between smoking and other

risk factors, “a general effect of current cigarette smoking was not

noted.”

 

Hypertension

The relationship between “impotence” and “erection dysfunction” and

hypertension was examined in a review of studies that were conducted in the 1970s

and 1980s33(p. 204). Impotence was found in 7% of men with normal blood pressure.

Impotence was found in 17% to 23% of untreated men with hypertension and in 25%

to 41% of men who were treated for hypertension. From these studies, the association

between “impotence” and hypertension (apart from drugs used in its treatment) is

clearly evident.

 

Lip ids

In the MMAS, a negative correlation was found between “impotence” and high density

lipoprotein cholesterol, although this was not so with total serum cholesterol.

“In the older men (age 56 to 70 years), the age-adjusted probability

of ‘moderate impotence’ increased from 6.7% to 25% as high

density lipoprotein cholesterol decreased from 90 to 30 mg./dl.”6

 

Medications

A variety of drugs used presently and in the recent past have been shown

to interfere with erectile function in men (see Appendix III). The increase

in the number of new drugs that are currently being introduced for various

human ailments and the increased speed with which they appear on

the market make it likely that unanticipated side effects (including sexual

side effects) of these agents will become apparent only after they

have been used for a period of time. Physicians must therefore be constantly

sensitive to the possibility of sexual side effects (including effects

 

on the mechanism of erection) of newer drugs. The following comment was made about

hypotensive agents but applies equally to other drugs as well: “Although . . . certain

agents . . . . are likely to have sexual side effects [while] other agents . . . are unlikely

to be associated with erectile dysfunction, it is important to stress that any agent may

cause erectile difficulties in certain patients . . . there is [also] considerable individual

variation in vulnerability of erectile function to different drugs. In other words, the existing

literature can only serve as a general guide to patient management” (italics added)34 (pp. 111-112).

In the MMAS study, “complete impotence” was found to be present significantly more

often in men taking the following medications than in the sample as a whole (10%)6:

• Hypoglycemic agents (26%)

• Antihypertensives (14%)

• Vasodilators (36%)

• Cardiac drugs (28%)

This association was not found with lipid-lowering drugs.

Two groups of drugs (antihypertensives and medications used in psychiatry)

have been particularly implicated in the development of erectile

dysfunction33 (pp. 197-337).

Issues learned from sexual side effect research on antihypertensive

drugs (that apply to other substances as well) include the following

items32 (pp. 206-207):

• Possibility of late appearance (6 months or more)

• Lack of information about their effects on women

• Importance of assessing sexual symptoms of the underlying

disease

• Need to include information from partners

• Usefulness of information about masturbation

• Need to assess alcohol use and abuse

 

Alcohol

“With just a few drinks, most men experience transient boosts in sex drive and sociability.

With continued drinking, however, erection and ejaculation abilities systematically

decrease in a dose-related fashion to a point of total dysfunction.”

32 Although there are acute and chronic effects of alcohol on sexual

function, comments here focus on the latter. Studies relating to chronic

alcoholism and epidemiology, Nocturnal Penile Tumescence (NPT),

hormonal and neurologic effects have been reviewed.35

An examination of clinical experience in the care of approximately

17,000 male alcoholics over 36 years revealed that 8% spontaneously

described continued erectile problems after detoxification.36 Years later,

despite abstinence, 50% had not fully recovered their erectile function.

The continuation of sexual desire in these men indicates that their erectile problems

were unlikely to be simply a result of insufficient testosterone but rather more fundamental

structural and functional body changes, including:

• Effect on testosterone receptors

 

• Influence of estrogen

• Damage to organs in the body, including the central nervous system,

testicles, and liver

• Existing diseases caused or made worse by alcohol abuse such as diabetes,

heart disease, and peripheral neuropathy

In addition, two controlled studies on the effects of alcoholism on sexual function

demonstrate that erectile dysfunction37 and also desire problems38 were more common

in alcoholic men.

In an effort to assess the effect of alcohol use on NPT, 26 sober, healthy, sexually

functional, and medication-free chronic alcoholics and controls were studied for two

nights in a laboratory setting.39 The subjects had fewer full penile tumescent episodes

that were also shorter in duration. The authors speculated on the possible contribution

of central processes to the effects of alcohol on erections.

The impact of chronic alcoholism on pituitary-gonadal function appears at both

levels. Apart from liver disease, chronic alcoholic men show evidence of hypogonadism,

abnormalities in spermatogenesis, and testicular atrophy.40 Such men also demonstrate

diminished androgens, elevated estrogens, and increased prolactin levels.

The neuropsychiatric effects of chronic alcoholism on sexual function may involve

central and peripheral processes. Alcohol-induced peripheral neuropathy may result in

both erectile and ejaculatory disorders. Schiavi outlined many of the psychological

factors that may also be present such as preexisting personality problems,

mood disorder, and feelings of inadequacy.35 He concluded that

“the reciprocal interaction between drug intake and psychological factors

is so closely interwoven that it is impossible to identify the nature

of this relation.”

 

Endocrine Abnormalities

“Erectile dysfunction of exclusively endocrine origin is uncommon. . . In most cases

the primary effect of the endocrine abnormality is loss of sexual interest.”12 The authors

of the MMAS study arrived at a similar conclusion.6” Of the 17 hormones measured in

the MMAS, “only dehydroepiandrosterone showed a strong correlation with impotence.”

Specifically, no correlations were found between “impotence” and the following

hormones:

• Testosterone (total or free)

• Sex hormone binding globulin (SHBG)

• Estrogens

• Prolactin

• Luteinizing hormone (LH)

• Follicle stimulating hormone (FSH)

When hormonal difficulties occur in the context of erectile dysfunction, the more

common clinical abnormalities are those that involve the hypothalamus-pituitarygonadal

axis and include: hypo- and hypergonadotropic hypogonadism, hyperprolactinemia,

and hypo- and hyperthyroidism.41 (p. 85). The frequency of the association

of endocrine and erectile problems depends on the age of the sample and the

 

clinical context of the investigation (e.g., outpatient medical, urology, endocrine, or

sex therapy clinics), as well as the nature of the sample.

When the particular association of erection problems and hyperprolactinemia

(HPRL) was reviewed, the observation was made that this was “often the first, and for

a long time the only symptom of HPRL, an important point because in many cases the

cause is a pituitary tumor.”12

Buvat and Lemaire reviewed large published series of endocrine abnormalities in

cases of erectile dysfunction and when combining their own results with others

found an 8% prevalence for low testosterone and 0.7% of prolactin levels greater

than 35 ng./ml.42

 

Aging

See “Sexual-developmenl History: The Older Years” in Chapter 5.

 

Laboratory Investigation

When the history and physical examination (see the “General Considerations” section

above in this chapter) leave doubt about the origin of a patient’s erectile dysfunction,

the clinician must also consider the use of laboratory tests.

The availability of orally administered treatments for erectile dysfunction (for

example, sildenafil—see “Treatment” below in this chapter) that appear to be easy to

use, often effective, and have minimal side-effects may well have profound effects on

the process of evaluating erectile dysfunction. The initial use of these medications by

a patient may, itself, become a test, and in so doing may replace some other investigatory

procedures. Nothing, however, should replace a careful clinical assessment and “when

there is suspicion of an organic factor, one should rely (as well) on a combination of

investigations.”13

Laboratory investigation of generalized erectile dysfunction chiefly entails examining

three body systems:

• Endocrine

• Vascular

• Neurological

Several diagnostic tests involving these three systems have been developed. The criteria

used in considering which diagnostic tests are appropriate for investigating generalized

erectile dysfunction on a primary care basis are:

1. Usefulness

2. Low cost

3. Noninvasiveness

4. Low complexity

5. Availability

 

Endocrine Blood Tests

Endocrine and blood tests for diabetes are probably the only procedures that fulfill the

criteria outlined immediately above. Despite agreement on the endocrine disorders most

commonly associated with erection difficulties,“. . . . there is disagreement on the specific
tests to be employed or the interpretation thereof”41 (p. 85). Many

suggest the need to measure Testosterone (T) and Prolactin (PRL) in all

men with erection difficulty (PRL can be abnormal when T is not). However,

others promote a more specific policy. For example, Buvat and

Lemaire suggest that before age 50, T should be determined only in cases

of (accompanying) low sexual desire and abnormal physical examination

but that after age 50 it should be measured in all men, and that PRL should

be determined only in cases of (accompanying) low sexual desire, gynecomastia,

and/or testosterone less than 4 ng/ml.42 These authors also direct clinicians to

repeat first results of abnormal prolactin and testosterone determinations because of their

finding of normal second results in 40% of their cases.

Apart from measuring total testosterone, this hormone also can be determined in the

bioavailable form (BAT) and as free testosterone (FT). BAT consists of FT and the fraction

that is bound to albumin41 (p. 76).

Conflicting opinions exist over the need to also immediately test some or all of the

following other factors without waiting for an abnormal T or PRL result:

• Follicle Stimulating Hormone (FSH)

• Luteinizing Hormone (LH)

• Sex Hormone Binding Globulin (SHBG)

• Thyroid function tests

Cost of testing and the nature of the clinical context are two elements resulting in differences

of opinion. In the literature, it seems assumed that these other factors would

be measured in the event of an abnormal T or PRL level.

 

Tests for Diabetes

Fasting blood sugar (FBS) or fasting plasma glucose (FPG) and/or glycosylated hemoglobin

(HgA1C) is widely used as a screening test for diabetes. A positive test indicates

that a confirming diagnostic test is warranted.43

 

Vascular Tests

Since the penis is, basically, a vascular organ, vascular tests are often important elements

in the evaluation of erectile difficulties, particularly when there is suspicion that

vascular elements may contribute to the etiology. However, tests of

penile vascular function are mostly invasive, costly, complex, difficult

to interpret, and have limited availability. As such they are generally

conducted by urologists and not recommended in primary care unless a

physician has special training. Although vascular testing procedures

may not be recommended for use in primary care, clinicians should be

aware of their potential diagnostic benefits and limitations to determine

the need for urological consultation.

Assessment of the penile response to the intracavernous injection

(ICI) of vasoactive agents has been found to be particularly useful in

considering vascular function. While structural problems with cavernosal

arteries may explain a negative response, anxiety can as well.44 “A

positive erectile response implies normal veno-occlusive function.

 

Nonresponders bear a high probability of a vascular origin with a predominance of

veno-occlusive insufficiency.”29

From a procedural viewpoint, the most common substances used for intracavernosal

injections are papaverine, papaverine-phentolamine mixture, or prostaglandin E1

(PGE1). The most worrisome complication of ICI is that of prolonged erection. A

comparative study of these three medications demonstrates that PGE1 had the highest

erection rate (75%) and lowest prolonged erection rate (i.e., requiring “interruption”

[0.1%]).45 After six hours of continuous erection, there is insufficient blood supply to

the erectile tissue. In this situation, the corpora cavernosa need to be drained to

decrease the intracavernosal pressure and an adrenergic agonist (e.g., 10 mg of adrenaline)

injected intracavernosly.29 In clinical practice, patients must be told to contact their physician

long before six hours if their erection persists.

Pharmacopenile Duplex Ultrasonography (PPDU) provides “an estimate of penile

arterial inflow and venous outflow . . . [and] . . . has become a first-line test to

define vascular [erectile dysfunction]”29 It allows for accurate location of penile arteries

and measurement of the diameter of each artery and provides evidence of the thickness

and pulsatility of arterial walls.12 In addition to assessment of the state of the cavernosal

arteries, PPDU can locate well-defined pathological conditions such as Peyronie’s

disease. The procedure for PPDU involves the creation of an erection through

ICI (needed because the procedure is unreliable when a penis is in the flaccid state)

and then simultaneously combining ultrasound color imaging of the arteries to the

cavernosal bodies of the penis with an analysis of blood flow patterns.

 

Nonspecific Tests: Nocturnal Penile Tumescence (NPT)

Any discussion of erectile dysfunction assessment is incomplete without including

NPT testing, since it is so widely used and so frequently included in the literature on

this subject. NPT is based on the discovery that a period of sleep involves different

stages and that one of those stages (REM) is associated with many body changes,

including the development of erection in men (three or four times each night and

occupying about 20% of total sleep time). It was assumed that erections that occur at

night and those which occur during the day involve the same body mechanisms and

that by comparing sleep and daytime erections, it would be possible to distinguish the

psychological or organic nature of the etiology of erection dysfunction. Sleep erections

are considered to be unaffected by waking psychosocial factors.

When used in-home, NPT testing fulfills many of the primary care criteria previously

described insofar as it is inexpensive, not extraordinarily complex to use, noninvasive,

and available. However, when done in a sleep laboratory, NPT is the opposite

in that it is expensive, cumbersome, and frequently unavailable in many geographic

areas. The chief doubt about NPT is its usefulness.

When used in such a way as to provide clearest interpretation, the test is performed

in a sleep laboratory with measurement of other sleep parameters such as electroencephalograph

(EEG), respiration, and electromyograph (EMG), and recordings are

made on at least two nights. The purpose in monitoring other sleep parameters is the

detection of interference with sleep or REM such as might happen with illness or

medication, which might result in mistaken conclusions.

Because of the complexity, expense, and difficulties with availability associated with

formal testing of NPT in a hospital setting, three in-home procedures have been developed46

(p. 153):

1. The “stamp” test (a ring of stamps placed around the base of a man’s penis)

2. Snap Gauge Band (one ring of a thin plastic material containing three others that

break at three different levels of tension as a penis enlarges)

3. Portable NPT monitoring

“Stamp” test results are difficult to interpret because of such problems as falsepositive

findings due to accidental tearing of the stamps for reasons other than an

erection, false-negative results due to slippage, and lack of standardization. Snap Gauge

has similarly been found to be of limited value. Both the stamp test and Snap Guage

provide information about changes in circumference only, nothing about rigidity or

stiffness (a vital issue in the assessment of erectile capacity for intercourse), and no

data concerning the number or duration of tumescent episodes each night.

Portable monitors (e.g., Rigiscan) measure rigidity as well as the number and duration

of NPT episodes. Measurement of rigidity has for some time been regularly

included in NPT testing (now sometimes called NPTR with the “R” referring to rigidity).

Reasons include the finding of substantial “interindividual differences in the

increase of circumference associated with full erections and the recognition that maximal

increases in shaft circumference did not indicate adequate rigidity.”47

As inviting as these in-home methods of NPT testing might be, clinicians should be

fully aware of their considerable limitations. It is suggested that this test “should be

used only as screening tools in the context of a comprehensive medical and psychological

evaluation”46(p. 153).

Although the use of the Rigiscan at-home is certainly less troublesome and expensive

than NPT in a sleep laboratory, opinions differ concerning its usefulness. “Apart

from the lack of sleep data, it is impossible to know if such devices have been misused,

manipulated, or otherwise mishandled by the patient. Deliberate faking of results cannot

be excluded. . . .”12

Apart from issues of technology, patient reliability, and cost, the utility of NPT

itself has been questioned. After many years, the importace of NPT in the process of

evaluation of erectile dysfunction remains unclear. So, too, is the question about the

equivalency of sleep and sexual erections. Confusion abounds in findings that show, for

example, abnormal NPT results in men who are not sexually dysfunctional in circumstances

such as aging,47 depression,48 and diabetes.49 Conversely, normal NPT is reported in

men with multiple sclerosis who have daytime erectile difficulties.50

Conclusions about the use of NPTR when used in the clinical evaluation of erectile

dysfunction (in a sleep laboratory or at home) are summarized Box 11-3.

 

Treatment

“Whether psychological issues are co-determinates of the erectile problem or are reactive

to it is immaterial. A man’s emotional reaction to his erectile failure may be such

that it serves to maintain the erectile problem even when the initial physiological

causes are resolved . . . no patient, even those with a clear organic impairment of

erectile capacity, can be considered inappropriate for psychological as well as relevant

surgical or drug therapies for his sexual problem”.54 For these reasons, everything that

was written immediately above about the treatment of situational erectile difficulties is

also applicable to the acquired and generalized form.

 

Specific Treatments

Specific disorders and their sexual symptoms are often (not always) therapeutically

responsive to specific treatments. Therapy for hyper- and hypogonadotropic hypogonadism

and hyperprolactinemia have been reviewed elsewhere41 (pp. 86-91). Details

concerning treatment will not be discussed here, since primary care health professionals

likely seek consultation when encountering such a patient.

Other specific disorders and their sexual symptoms may not respond therapeutically

to specific treatment methods. Diabetes is an example. Careful control of insulindependent

and probably non-insulin-dependent diabetes mellitus will slow the onset

and delay the progression of early vascular and neurologic complications, two body

systems that have been particularly implicated in the etiology of erectile disorders in

this disease.55,56 Presumably, better control of diabetes would also delay the onset and

slow the development of sexual dysfunctions, including erectile difficulties. When

erectile dysfunction in specific disorders such as diabetes do not respond to specific

treatment, nonspecific approaches can be used.

 

Nonspecific Treatments

Dramatic developments in the treatment of the acquired and generalized

form of erectile dysfunction have been introduced in the past two

decades in the form of intracavernosal injections, intraurethral medication,

erections devices, and prostheses. As significant as these developments

have been, they might well be overshadowed by the introduction

of new oral therapies. The etiological and clinical heterogeneity

of the acquired and generalized form of erection dysfunction will likely

 

necessitate the continued use of several treatment approaches. Not everyone will benefit

from the new oral therapies. For this reason, the oral therapies and many of the

other currently used treatment approaches are discussed below.

 

Oral Therapies

Sildenafil (Viagra), is a new oral treatment that may be a critical advancement in the care

of men with erectile difficulties (Box 11-4).

As a result of factors such as the ease of administration, sildenafil (and other orally

administered substances currently being tested) will likely result in a substantial shift

in the treatment of men with erectile difficulties away from specialists and toward

physicians in primary care. Sildenafil demonstrated in initial trials to be well tolerated

and “effective in improving erectile activity in patients with male erectile dysfunction

for which there is no established organic cause.”57

 

As described above (see “Mechanism of Erection” in this chapter), relaxation of

smooth muscle is an essential aspect of the development of an erection. This relaxation

is mediated by nitric oxide via cyclic guanosine monophosphate (cGMP).59 Cyclic

nucleotide phosphodiesterase (PDE) isozymes hydrolyse cGMP. It was reasoned that

an inhibitor of PDE would therefore enhance the action of nitric oxide/cGMP on

penile erectile activity. Sildenafil is such an inhibiting agent.59 It is described as the first

representative of a new class of agents: an enzyme inhibitor (type 5 cyclic guanosine

monophosphate-specific phosphodiesterase isozyme) that results in the relaxation of

corpus cavernosum smooth muscle cells and thereby enhances penile erection in

response to sexual stimuli.60

An initial report on sildenafil involved 12 subjects and was conducted in two phases:

(1) a single dose in a laboratory and (2) once-daily doses at home for seven days, 1

to 2 hours before sexual activity was likely to occur.57 Both phases were placebocontrolled,

double-blind, and involved a cross-over design. The first included use of

the drug at three different doses and measured erectile response to visual sexual stimulation

using subject-chosen explicit videos and magazines. In the second phase, subjects

kept a diary and graded their erections. Results from the first phase demonstrated

a significant difference in penile rigidity between all three doses of sildenafil and placebo,

with the difference being more substantial as the dose increased. The in-home

phase showed that higher quality erections occurred more often when men were on

the drug. Adverse events were described as “mild and transient.”

Another report on sildenafil was conducted on 250 patients with erectile dysfunction

of “predominantly no known organic cause.”61 Patients previously were involved

in an open dose study and were randomized to receive their optimum dose of the

medication or placebo. They were asked to compare their erections in the present

study to those they experienced in the open trial. Of those given sildenafil, 59%

reported no change, and of those receiving placebo, 72% reported their erections as

“much worse.” The authors concluded that sildenafil must be continued

for the erectile improvement to be maintained.

The most complete report on oral sildenafil (as of Spring 1998) was

published in the New England Journal of Medicine (NEJM). It involved

a total of 861 men with erectile dysfunction described as organic, psychogenic

or mixed.62 Two studies were conducted: (1) a dose-response

study on 532 men treated with 25, 50, 100 mg or placebo and (2) a

dose-escalation study involving 329 different men treated initially with

50 mg or placebo and subsequently with one half or twice the amount

of the original dosage, depending on efficacy and tolerance. These

studies were performed in a natural environment and therefore relied

on the subjects’ reports of efficacy.

In the first study (dose-response) in the NEJM report, increasing doses of sildenafil

were associated with significantly increased “frequency of penetration” and maintenance

of erections after entry (p<0.001). Interestingly, the cause of the erection difficulty did

not affect the outcome. In the second study (dose-escalation), improvement of the same

two measures were significantly better for sildenafil compared to placebo (p<0.001), as

were several other measures, including “overall satisfaction.” (However, in this same

study, sexual desire scores were not different in the two groups). In the dose-response

 

study, the frequency of erections sufficiently firm for intercourse to occur was 72%,

80%, and 85% for doses of 25 mg, 50 mg, and 100 mg, respectively (versus 50% for the

placebo group; (p<0.001). In the dose-escalation study, 69% of attempts at intercourse

(versus 22% for the placebo group) were successful (p<0.001).

Yohimbine is one of the more widely used and studied oral agents used recently in the

treatment of erectile dysfunction. It is an alkaloid derivative that is found in the bark

of the yohimbine tree and has a long-standing reputation as an aphrodisiac.63 Part of

the attractiveness of yohimbine is the “benign side effect profile”33 (p. 123). Pharmacologically,

yohimbine is a preferential presynaptic alpha 2 antagonist. The dose ranges

from 2 to 6 mg three times per day, and has shown to have a positive effect on sexual

behavior in animals).64 However, a review of the outcome of several studies of men

with erectile dysfunction indicates that while yohimbine may have the capacity to

affect sexual desire and performance in some subjects, “results have been far from conclusive

[since] more than half of all patients studied thus far have shown little or no

benefit from the drug.”63 A meta-analysis of studies of the effect of yohimbine in men

with erection difficulties concluded the opposite, namely, that it was consistently helpful

compared to placebo.65 It may be that the heterogeneity of men with erection

difficulties that is evident in many studies has disguised a beneficial effect of this

substance in a particular subpopulation. One hypothesis suggests that men with a

“nonorganic

etiology” might derive a greater benefit than other men.64

Androgens often have been administered to men with erection difficulties, frequently

without establishing the presence of an endocrinopathy. Studies of androgen treatment

in erectile dysfunction that included hormonal assessments strongly suggest that it “is

of little value in eugonadal males”40 (p. 91). The hazards of androgen therapy in this

situation have not always been considered. Given the fact that erectile dysfunction and

prostate cancer become more evident with increasing age, clinicians need to be especially

concerned about the potentially negative effect of androgens (even on a trial

basis) on the prostate gland (see Etiology, “Endocrine Abnormalities” above in this

chapter).

 

Intracavernosal Injections (ICI)

Injection of medications directly into one of the corpora cavernosa of a man’s penis as

a treatment of erectile dysfunction became an accepted and widely used treatment

method in the 1980s. It would not be surprising to see this approach greatly diminish

in popularity with the advent of an efficacious and safe oral medication.

Three substances are currently used for ICI:

• Papaverine hydrochloride

• Phentolamine mesylate

• Prostaglandin E1 (PGE1)

Papaverine has been used alone or in combination with phentolamine; PGE1 has been

used alone or together with papaverine and phentolamine as Trimix. One formulation

of PGE1 is alprostadil. The subject of ICI treatment is thoroughly reviewed elsewhere.

66,67

Dosages are generally titrated to the response of the patient. PGE1 alone is

the substance most commonly used by urologists and the dose is typically in the range

of 1 to 40 μg.67 Smaller doses of medications used in ICI are generally required in

instances of neurogenic (and “psychogenic”) erectile dysfunction.

ICI seems most efficacious in the context of a neurological deficit (e.g., spinal cord

injury) and least helpful in men who have severe corporal veno-occlusive dysfunction

and/or arterial insufficiency. Contraindications include poor manual dexterity, morbid

obesity, and anticoagulant therapy.67 Injection usually results in a partial erection

within minutes and the addition of sexual stimulation usually increases the enlargement.

68 Patient’s are taught the technique of injection (usually by a urologist or nurseeducator)

and “observed while self-injecting so that the physician has an opportunity

to advise and correct his technique.” Patients then inject themselves at home.67 One

side effect, namely, prolonged erection (defined as more than four hours), requires

immediate medical attention. The frequency of prolonged erection (priapism) and

other side effects depends on the medication used. Side effects include the following:

• Fibrotic nodules (more with papaverine and/or phentolamine)

• Pain (about 10% to 34% with PGE1 alone)

• Infection

• Bruising

• Liver function abnormalities

• Vasovagal episodes

Prolonged erections appear to more common with papaverine alone (10% of patients)

than PGE1 alone (2% of patients). The incidence of priapism seems to be less with the

mixture of papaverine-phentolamine-PGE1.67 Priapism rates for home injections are

considerably less (0.3%) than in-office trial injections. When priapism occurs, emergency

intervention is required, and most cases resulting from papaverine and/or

phentolamine respond to aspiration alone, or in combination with intracorporal installation

of a diluted alpha-adrenergic receptor agonist such as epinephrine (limited to

less than 15 μg at intervals of more than five minutes to avoid systemic side

effects).69

Fibrotic plaques are reported to be less common with PGE1 than with papaverine

and/or phentolamine, and there have been no reports of liver disease with either of

these substances or with PGE1 despite abnormalities on liver function testing.67 Pain

during injection is commonly reported by men using PGE1 (75% in one study) but

pain is infrequent with papaverine and/or phentolamine.67

The impact of ICI on patients and their partners was studied and beneficial changes

were described in each, particularly in the areas of self-esteem, sexual desire, frequency,

and satisfaction.66,67

Although ICI is considered safe and reliable, many patients do not continue using

it in the short-run for several reasons, including67:

1. The feeling that it was unnatural

2. Concerns about side effects

3. Lack of a regular partner

4. Fear of being belittled by the partner

In addition to immediate issues, there is a surprisingly high (50%) drop out rate at 12

month follow-up. Reasons given include loss of efficacy and loss of interest. The high

drop out rate suggests the need for a careful initial evaluation of the motivation of the

patient and partner and willingness to accept ICI on the part of both.

 

Transurethral Alprostadil

Alprostadil is a synthetic compound identical to PGE1. A transurethral method of delivering

this medication was developed as an alternative to intracavernosal injections. With

medicated urethral system for erection (MUSE), a proprietary drug delivery system, the

medication is put into a tiny pellet and deposited into the end of the urethra with an

applicator. A man urinates before insertion of the applicator to lubricate his urethra.

Route of administration of any medication may result in different side effects even

though the substance might be the same. In the form of intracavernosal injections,

alprostadil enters directly into the corpus cavernosum of the penis. When given transurethrally,

the medication is absorbed from the urethral mucosa, enters the body’s

blood stream, and then is returned to the penis.

In a double-blind and placebo-controlled study, 1511 men aged 27 to 88 with “chronic

erectile dysfunction from various organic causes” were treated with transurethral alprostadil.

70 To determine maximal penile response, subjects were given the opportunity to

use up to four alternative doses of the drug: 125, 250,500, or 1000 μg. The 996 men

who responded in a clinic setting were then randomly assigned to the selected dose or

placebo. Eighty-eight percent of the men completed the three month course of treatment.

Significantly more men in the alprostadil group (65%) reported having intercourse

at least once and the medication was significantly more effective than placebo

regardless of age or the cause of the erectile dysfunction.

The most common side effect of transurethral alprostadil was penile pain (reported

by 33% of the men) but was considered mild and resulted in only 20% of the men

leaving the study.70 Other side effects include mild urethral trauma (5%), dizziness

(2%), and urinary tract infections (“rare”).

Transurethral alprostadil is particularly advantageous in primary care. For the physician

the procedure is greatly simplified (compared to ICI) in that the medication is

self-administered and does not require an in-office training procedure. From the

patient’s perspective, the process is less complex to learn and to use at home and free

of the potentially serious side effects of priapism and fibrosis associated with ICI.

 

Vacuum Erection Devices

Vacuum erection devices (VEDs) are also called vacuum constriction, and external

vacuum, devices (information available through Imagyn Technologies at

1-800-344-9688). Like intracavernosal injections, the use of VEDs may diminish considerably

with the advent of a safe and effective oral treatment for erectile dysfunction.

However, for the foreseeable future, VEDs are likely to remain in the armamentarium

of health professionals who treat men with erectile dysfunction. The need is exemplified,

for example, in men for whom a physical approach is recommended but who

strongly prefer not to use any kind of drugs for an ailment that could be treated in a

nonpharmacological manner. The subject of VEDs is reviewed in detail elsewhere.66

When first introduced in the early 1980s, “the concept [of VEDs] seemed difficult

for physicians to accept. In an era of high technology, perhaps the low technology and

simplicity of vacuum devices are disarming and provoke rejection”66 (p. 297). Precisely

because they are “low tech,” safe, and efficacious, VEDs are likely to remain of particular

interest to primary care clinicians.

The mechanism of action is fundamentally the same for the various VEDs that exist.

Procedures are as follows:

• A cylinder is placed over a man’s flaccid penis and pressed firmly against

his body to create an airtight seal

• Air is pumped out of the cylinder to create a vacuum

• Blood is, in the process, drawn into his penis

• After an erection exists, a tension band is transferred from the VED to

the base of the man’s penis

• A vacuum release valve is then opened and the cylinder is removed

VED-induced erections are passively created by suction and venous stasis that results

from constriction, in contrast to erections produced naturally (and by ICI), which are

actively created by neurotransmitters and relaxation of corpora smooth muscle. Several

studies demonstrate that 90% of men who have “organic,” “mixed,” and “psychogenic”

erection dysfunction and use this system are able to have sufficiently firm erections for

the purpose of intercourse.66

The most common side effects reported with VEDs are hematoma and petechiae

(8% to 50%).66 These are generally not considered serious and resolve without medical

intervention. Other side effects include the following:

• Pain

• Numbness of the penis

• Pulling of scrotal tissue into the cylinder

• Blocked and painful ejaculation

Patient acceptance is estimated at 80% to 95%. The reasons for discontinuing the

use of a VED include the following:

• Mechanical difficulty

• Failure to produce an adequate erection

• Feeling that the device is cumbersome

• A sense that the erection is artificial

There are three contraindications: men with Peyronie’s Disease,

concurrent blood dyscrasia or use of anticoagulants, and poor manual

dexterity (which can be overcome by the use of a battery operated

device).

Table 11-1 summarizes comparisons between VEDs and ICI. Since they are both

equally efficacious and have a positive effect on patients, “the critical discriminations

need to be made on the basis of cost, potential side effects, patient acceptance, and

aesthetic preferences of the man or couple”66 (p. 304).

 

Penile Prostheses

The use of prostheses (or implants) in the treatment of men with erectile dysfunction

is generally considered “a last resort,” since surgery involves the destruction of structures

which are otherwise normally involved in the erectile process. The irreversibility

 

of prosthesis implantation limits its use given the rapid progress in the development of

more benign approaches to the treatment of this disorder. The subject of prostheses

has been thoroughly reviewed elsewhere.71

Implants have been used since the early 1950s and now exist in a variety of forms:

semirigid silicone only; semirigid, silicone interior; and inflatable.71 “Most operating

rooms stock one type of semirigid device and the inflatable prosthesis used most

often by the implanting surgeons” (p. 270). Some factors that influence the choice of

device include: cost, availability, esthetics, and manual dexterity (to use the inflatable

type) (p. 271).

In a follow-up examination on the satisfaction of patients (n = 52) and their partners

(n = 22), which involved interviewing the two people separately and had a

response rate of 72%, the kind of device implanted made little difference to the men.

However, the patient’s partner preferred inflatable implants.72 All except four had

intercourse more than “infrequently.” Almost 80% of the men said they would undergo

the operation again but only 60% of the partners said that they had no hesitations.

The goal of treatment with penile prostheses can vary greatly and depends to a

large extent on the perspective of the discipline of the person stating an opinion. Some

 

 

urologists focus specifically on the issue of erection, whereas mental health professionals

and sex therapists concentrate more broadly on sexual satisfaction of the two partners.

One follow-up study did not resolve the conflict (but leaned more toward the

view of sex therapists), since it demonstrated that the greatest benefit is the sense of

“restored manhood.” “The feeling of being capable of coitus, was reported by many of

the men in the study as a prime benefit of surgery” (italics added)71 (p. 273). Screening

issues have been identified to detect patients for whom penile prosthesis implantation

is planned but who might benefit also from preventive counseling.73 These include the

following factors:

• Concern about the importance of penile size in sexual activity

• Disinterest in foreplay

• Low sexual desire in either partner

• Premature ejaculation

• Untreated vaginal atrophy in the woman

 

Indications for Referral for Consultation or Continuing Care by a Specialist

The treatment of solo men, or couples, in which the man has an acquired and generalized

form of erectile dysfunction requires attention to both physical and psychological

etiological issues. The more the etiologies are known, the more specific will be the

treatment, as well as the kind of health professional needed to provide the necessary

form of care. Referral for medical specialist consultation may be useful in, for example,

the following specific and defined circumstances:

• Endocrine disorders

• Diabetes

• Cardiovascular disorders (including hypertension)

• Major depression

Referral to a urologist for continuing care might be beneficial in instances of “venous

leak.”

When complex, expensive, or physically invasive diagnostic procedures are necessary

to clarify the etiology, consultation with a urologist who is knowledgeable about

erectile disorders is required. Buvat reminded clinicians of “ . . . Cochran’s aphorism:

‘before doing a test, decide what to do if it is (a) positive and (b) negative. If both

answers are the same, don’t do the test.”12

When the etiology is unknown (or the etiology known but not responsive to specific

therapy), treatment is nonspecific. The advent of safe and effective oral therapies

will likely result in many more men with erectile dysfunction being identified and

cared for on a primary care basis than at present. However, liberal use should be made

of other health professionals (especially urologists and sex therapists) when cases are

treatment-resistant (for the purpose of consultation and possible implementation of

other nonspecific treatment approaches).

 

Summary

Impotence is a term that is widely used and accepted but falls short of being helpful for

two reasons: (l) confusion, since several conditions are grouped in the same category

and (2) even more confusion, since the disorders have nothing to do with power (the

origin of the word “potency”).

The prevalence of erectile disorders is 40% of men at age 40 and 66% at age 70.

The resources needed to treat this widespread problem are substantial and will become

even more substantial as the aging population increases.

In the same way that different cardiac disorders manifest in similar ways despite

having several origins, so do erectile disorders. While the chief manifestation of an

erectile disorder is a soft penis rather than a hard one, the pattern of erection function

matters when considering etiology (“psychogenic” and “organic”) and treatment. An

erectile problem that is generalized (exists in all situations: with a partner, in the morning,

and with masturbation) suggests a different etiological and treatment direction

than one that is situational (erections are unimpaired in some situations). Likewise, it

matters if erection problems have always existed, since the man has been sexually

involved with others (lifelong) or developed more recently (acquired).

Causes of erectile disorders (often more than one) include the following:

• Medical disorders (endocrine, cardiovascular, neurological)

• Drugs

• Elevated blood lipids

• Cigarette smoking

• Psychiatric disorders

• Relationship problems

• Anxiety

In any investigation of an erectile disorder, history-taking is essential, a physical

examination is necessary (although the yield is low), and laboratory tests are required

if the pattern of erectile dysfunction even hints at being generalized.

Treatment of erectile disorders are sometimes specific to the etiology (e.g., replacing

a hormone that exists in insufficient amounts) and sometimes nonspecific, for

example, oral medications (sildenafil [Viagra], psychotherapy, or intracavernosal injections.

Counseling intervention ranges from being central (sex therapy) to being an

adjunct (e.g., information about the use of vacuum erection devices).

The prevalence of erectile disorders makes primary care health professionals central

to the care of men (and couples) with this disorder. Their task will likely be made

easier by the introduction of safe and effective oral therapies. However, even with the

advent of new forms of care there still will be treatment-resistant patients and couples,

and in those instances, liberal use should be made of other approaches and specialists.

 

Postscript

When a patient takes no action after treatment suggestions are made for erectile difficulties,

clinicians should not necessarily be surprised or discouraged.

 

A 57-year-old divorced computer analyst was seen because of long-standing (about

ten years) erectile difficulties that appear when alone in masturbation and on the

occasional times he is sexually active with a partner. He experienced a myocardial

infarction four years before the referral. He lived alone for 25 years after a marriage

that lasted three years. The longest relationship he had with a woman since then

(he was not romantically or sexually interested in men) was four months and that

was about 20 years before. Since then he had a few dates but none in the previous

ten years because he felt that women would expect him to do what he felt was not

possible, that is, to sexually “perform.” Discontented with the suggestions made at

the end of a thorough assessment, he insisted on special diagnostic vascular procedures

about which he had read. He was unwilling to consider oral medications,

intracavernosal injections, or VEDs and was angry about the suggestion of psychiatric

care as part of a treatment “package.” He did not appear again after two visits

and canceled his last appointment.

 

A survey of men assessed for erectile problems in a urology clinic found that two years

later over half had not followed up on recommendations.74 Sexual and nonsexual reasons

may have existed. A strong desire for return of erectile capability may not be

durable after the discovery that treatment entails significant psychological and/or

physical effort and discomfort. In addition, some men are quite resistant to the notion

that the explanation for problems with the function of their genitalia may, in fact, lie

elsewhere (e.g., the problems may be an expression of intimacy difficulties [see Appendix

II]).

 

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