Dr.Joe's Data Base
ERECTILE DYSFUNCTION NIH
National Institutes of Health Consensus Development Conference Statement
December 7-9, 1992
This statement is also published as:
Impotence. NIH Consens Statement 1992 Dec 7-9;10(4):1-31.
For making bibliographic reference to the statement in the electronic
form displayed here, it is recommended that the following format be
used:
Impotence. NIH Consens Statement Online 1992 Dec 7-9 [cited year month
day];10(4):1-31.
ABSTRACT
The National Institutes of Health Consensus Development Conference on
Impotence was convened to address (1) the prevalence and clinical,
psychological, and social impact of erectile dysfunction; (2) the risk
factors for erectile dysfunction and how they might be used in
preventing its development; (3) the need for and appropriate diagnostic
assessment and evaluation of patients with erectile dysfunction; (4) the
efficacies and risks of behavioral, pharmacological, surgical, and other
treatments for erectile dysfunction; (5) strategies for improving public
and professional awareness and knowledge of erectile dysfunction; and
(6) future directions for research in prevention, diagnosis, and
management of erectile dysfunction. Following 2 days of presentations by
experts and discussion by the audience, a consensus panel weighed the
evidence and prepared their consensus statement.
Among their findings, the panel concluded that (1) the term "erectile
dysfunction" should replace the term "impotence"; (2) the likelihood of
erectile dysfunction increases with age but is not an inevitable
consequence of aging; (3) embarrassment of patients and reluctance of
both patients and health care providers to discuss sexual matters
candidly contribute to underdiagnosis of erectile dysfunction; (4) many
cases of erectile dysfunction can be successfully managed with
appropriately selected therapy; (5) the diagnosis and treatment of
erectile dysfunction must be specific and responsive to the individual
patient's needs and that compliance as well as the desires and
expectations of both the patient and partner are important
considerations in selecting appropriate therapy; (6) education of health
care providers and the public on aspects of human sexuality, sexual
dysfunction, and the availability of successful treatments is essential;
and (7) erectile dysfunction is an important public health problem
deserving of increased support for basic science investigation and
applied research.
The full text of the consensus panel's statement follows.
INTRODUCTION
The term "impotence," as applied to the title of this conference, has
traditionally been used to signify the inability of the male to attain
and maintain erection of the penis sufficient to permit satisfactory
sexual intercourse. However, this use has often led to confusing and
uninterpretable results in both clinical and basic science
investigations. This, together with its pejorative implications,
suggests that the more precise term "erectile dysfunction" be used
instead to signify an inability of the male to achieve an erect penis as
part of the overall multifaceted process of male sexual function.
This process comprises a variety of physical aspects with important
psychological and behavioral overtones. In analyzing the material
presented and discussed at this conference, this consensus statement
addresses issues of male erectile dysfunction, as implied by the term
"impotence." However, it should be recognized that desire, orgasmic
capability, and ejaculatory capacity may be intact even in the presence
of erectile dysfunction or may be deficient to some extent and
contribute to the sense of inadequate sexual function.
Erectile dysfunction affects millions of men. Although for some men
erectile function may not be the best or most important measure of
sexual satisfaction, for many men erectile dysfunction creates mental
stress that affects their interactions with family and associates. Many
advances have occurred in both diagnosis and treatment of erectile
dysfunction. However, its various aspects remain poorly understood by
the general population and by most health care professionals. Lack of a
simple definition, failure to delineate precisely the problem being
assessed, and the absence of guidelines and parameters to determine
assessment and treatment outcome and long-term results, have contributed
to this state of affairs by producing misunderstanding, confusion, and
ongoing concern. That results have not been communicated effectively to
the public has compounded this situation.
Cause-specific assessment and treatment of male sexual dysfunction will
require recognition by the public and the medical community that
erectile dysfunction is a part of overall male sexual dysfunction. The
multifactorial nature of erectile dysfunction, comprising both organic
and psychologic aspects, may often require a multidisciplinary approach
to its assessment and treatment. This consensus report addresses these
issues, not only as isolated health problems but also in the context of
societal and individual perceptions and expectations.
Erectile dysfunction is often assumed to be a natural concomitant of the
aging process, to be tolerated along with other conditions associated
with aging. This assumption may not be entirely correct. For the elderly
and for others, erectile dysfunction may occur as a consequence of
specific illnesses or of medical treatment for certain illnesses,
resulting in fear, loss of image and self-confidence, and depression.
For example, many men with diabetes mellitus may develop erectile
dysfunction during their young and middle adult years. Physicians,
diabetes educators, and patients and their families are sometimes
unaware of this potential complication. Whatever the causal factors,
discomfort of patients and health care providers in discussing sexual
issues becomes a barrier to pursuing treatment.
Erectile dysfunction can be effectively treated with a variety of
methods. Many patients and health care providers are unaware of these
treatments, and the dysfunction thus often remains untreated, compounded
by its psychological impact. Concurrent with the increase in the
availability of effective treatment methods has been increased
availability of new diagnostic procedures that may help in the selection
of an effective, cause-specific treatment. This conference was designed
to explore these issues and to define the state of the art.
To examine what is known about the demographics, etiology, risk factors,
pathophysiology, diagnostic assessment, treatments (both generic and
cause-specific), and the understanding of their consequences by the
public and the medical community, the National Institute of Diabetes and
Digestive and Kidney Diseases and the Office of Medical Applications of
Research of the National Institutes of Health, in conjunction with the
National Institute of Neurological Disorders and Stroke and the National
Institute on Aging, convened a consensus development conference on male
impotence on December 7-9, 1992. After 1 1/2 days of presentations by
experts in the relevant fields involved with male sexual dysfunction and
erectile impotence or dysfunction, a consensus panel comprised of
representatives from urology, geriatrics, medicine, endocrinology,
psychiatry, psychology, nursing, epidemiology, biostatistics, basic
sciences, and the public considered the evidence and developed answers
to the questions that follow.
WHAT ARE THE PREVALENCE AND CLINICAL, PSYCHOLOGICAL, AND SOCIAL IMPACT
OF IMPOTENCE (CULTURAL, GEOGRAPHICAL, NATIONAL, ETHNIC, RACIAL,
MALE/FEMALE PERCEPTIONS AND INFLUENCES)?
Prevalence and Association with Age
Estimates of the prevalence of impotence depend on the definition
employed for this condition. For the purposes of this consensus
development conference statement, impotence is defined as male erectile
dysfunction, that is, the inability to achieve or maintain an erection
sufficient for satisfactory sexual performance. Erectile performance has
been characterized by the degree of dysfunction, and estimates of
prevalence (the number of men with the condition) vary depending on the
definition of erectile dysfunction used.
Appallingly little is known about the prevalence of erectile dysfunction
in the United States and how this prevalence varies according to
individual characteristics (age, race, ethnicity, socioeconomic status,
and concomitant diseases and conditions). Data on erectile dysfunction
available from the 1940's applied to the present U.S. male population
produce an estimate of erectile dysfunction prevalence of 7 million.
More recent estimates suggest that the number of U.S. men with erectile
dysfunction may more likely be near 10-20 million. Inclusion of
individuals with partial erectile dysfunction increases the estimate to
about 30 million. The majority of these individuals will be older than
65 years of age. The prevalence of erectile dysfunction has been found
to be associated with age. A prevalence of about 5 percent is observed
at age 40, increasing to 15-25 percent at age 65 and older. One-third of
older men receiving medical care at a Department of Veterans' Affairs
ambulatory clinic admitted to problems with erectile function.
Causes contributing to erectile dysfunction can be broadly classified
into two categories: organic and psychologic. In reality, while the
majority of patients with erectile dysfunction are thought to
demonstrate an organic component, psychological aspects of
self-confidence, anxiety, and partner communication and conflict are
often important contributing factors.
The 1985 National Ambulatory Medical Care Survey indicated that there
were about 525,000 visits for erectile dysfunction, accounting for 0.2
percent of all male ambulatory care visits. Estimates of visits per
1,000 population increased from about 1.5 for the age group 25-34 to
15.0 for those age 65 and above. The 1985 National Hospital Discharge
Survey estimated that more than 30,000 hospital admissions were for
erectile dysfunction.
Clinical, Psychological, and Social Impact
Geographic, Racial, Ethnic, Socioeconomic, and Cultural Variation in
Erectile Dysfunction. Very little is known about variations in
prevalence of erectile dysfunction across geographic, racial, ethnic,
socioeconomic, and cultural groups. Anecdotal evidence points to the
existence of racial, ethnic, and other cultural diversity in the
perceptions and expectation levels for satisfactory sexual functioning.
These differences would be expected to be reflected in these groups'
reaction to erectile dysfunction, although few data on this issue appear
to exist.
One report from a recent community survey concluded that erectile
failure was the leading complaint of males attending sex therapy
clinics. Other studies have shown that erectile disorders are the
primary concern of sex therapy patients in treatment. This is consistent
with the view that erectile dysfunction may be associated with
depression, loss of self-esteem, poor self-image, increased anxiety or
tension with one's sexual partner, and/or fear and anxiety associated
with contracting sexually transmitted diseases, including AIDS.
Male/Female Perceptions and Influences. The diagnosis of erectile
dysfunction may be understood as the presence of a condition limiting
choices for sexual interaction and possibly limiting opportunity for
sexual satisfaction. The impact of this condition depends very much on
the dynamics of the relationship of the individual and his sexual
partner and their expectation of performance. When changes in sexual
function are perceived by the individual and his partner as a natural
consequence of the aging process, they may modify their sexual behavior
to accommodate the condition and maintain sexual satisfaction.
Increasingly, men do not perceive erectile dysfunction as a normal part
of aging and seek to identify means by which they may return to their
previous level and range of sexual activities. Such levels and
expectations and desires for future sexual interactions are important
aspects of the evaluation of patients presenting with a chief complaint
of erectile dysfunction.
In men of all ages, erectile failure may diminish willingness to
initiate sexual relationships because of fear of inadequate sexual
performance or rejection. Because males, especially older males, are
particularly sensitive to the social support of intimate relationships,
withdrawal from these relationships because of such fears may have a
negative effect on their overall health.
WHAT ARE THE RISK FACTORS CONTRIBUTING TO IMPOTENCE? CAN THESE BE
UTILIZED IN PREVENTING DEVELOPMENT OF IMPOTENCE?
Physiology of Erection
The male erectile response is a vascular event initiated by neuronal
action and maintained by a complex interplay between vascular and
neurological events. In its most common form, it is initiated by a
central nervous system event that integrates psychogenic stimuli
(perception, desire, etc.) and controls the sympathetic and
parasympathetic innervation of the penis. Sensory stimuli from the penis
are important in continuing this process and in initiating a reflex arc
that may cause erection under proper circumstances and may help to
maintain erection during sexual activity.
Parasympathetic input allows erection by relaxation of trabecular smooth
muscle and dilation of the helicine arteries of the penis. This leads to
expansion of the lacunar spaces and entrapment of blood by compressing
venules against the tunica albuginea, a process referred to as the
corporal veno- occlusive mechanism. The tunica albuginea must have
sufficient stiffness to compress the venules penetrating it so that
venous outflow is blocked and sufficient tumescence and rigidity can
occur.
Acetylcholine released by the parasympathetic nerves is thought to act
primarily on endothelial cells to release a second
nonadrenergic-noncholinergic carrier of the signal that relaxes the
trabecular smooth muscle. Nitric oxide released by the endothelial
cells, and possibly also of neural origin, is currently thought to be
the leading of several candidates as this nonadrenergic-noncholinergic
transmitter; but this has not yet been conclusively demonstrated to the
exclusion of other potentially important substances (e.g., vasoactive
intestinal polypeptide). The relaxing effect of nitric oxide on the
trabecular smooth muscle may be mediated through its stimulation of
guanylate cyclase and the production of cyclic guanosine monophosphate
(cGMP), which would then function as a second messenger in this system.
Constriction of the trabecular smooth muscle and helicine arteries
induced by sympathetic innervation makes the penis flaccid, with blood
pressure in the cavernosal sinuses of the penis near venous pressure.
Acetylcholine is thought to decrease sympathetic tone. This may be
important in a permissive sense for adequate trabecular smooth muscle
relaxation and consequent effective action of other mediators in
achieving sufficient inflow of blood into the lacunar spaces. When the
trabecular smooth muscle relaxes and helicine arteries dilate in
response to parasympathetic stimulation and decreased sympathetic tone,
increased blood flow fills the cavernous spaces, increasing the pressure
within these spaces so that the penis becomes erect. As the venules are
compressed against the tunica albuginea, penile pressure approaches
arterial pressure, causing rigidity. Once this state is achieved,
arterial inflow is reduced to a level that matches venous outflow.
Erectile Dysfunction
Because adequate arterial supply is critical for erection, any disorder
that impairs blood flow may be implicated in the etiology of erectile
failure. Most of the medical disorders associated with erectile
dysfunction appear to affect the arterial system. Some disorders may
interfere with the corporal veno-occlusive mechanism and result in
failure to trap blood within the penis, or produce leakage such that an
erection cannot be maintained or is easily lost.
Damage to the autonomic pathways innervating the penis may eliminate
"psychogenic" erection initiated by the central nervous system. Lesions
of the somatic nervous pathways may impair reflexogenic erections and
may interrupt tactile sensation needed to maintain psychogenic
erections. Spinal cord lesions may produce varying degrees of erectile
failure depending on the location and completeness of the lesions. Not
only do traumatic lesions affect erectile ability, but disorders leading
to peripheral neuropathy may impair neuronal innervation of the penis or
of the sensory afferents. The endocrine system itself, particularly the
production of androgens, appears to play a role in regulating sexual
interest, and may also play a role in erectile function.
Psychological processes such as depression, anxiety, and relationship
problems can impair erectile functioning by reducing erotic focus or
otherwise reducing awareness of sensory experience. This may lead to
inability to initiate or maintain an erection. Etiologic factors for
erectile disorders may be categorized as neurogenic, vasculogenic, or
psychogenic, but they most commonly appear to derive from problems in
all three areas acting in concert.
Risk Factors
Little is known about the natural history of erectile dysfunction. This
includes information on the age of onset, incidence rates stratified by
age, progression of the condition, and frequency of spontaneous
recovery. There also are very limited data on associated morbidity and
functional impairment. To date, the data are predominantly available for
whites, with other racial and ethnic populations represented only in
smaller numbers that do not permit analysis of these issues as a
function of race or ethnicity.
Erectile dysfunction is clearly a symptom of many conditions, and
certain risk factors have been identified, some of which may be amenable
to prevention strategies. Diabetes mellitus, hypogonadism in association
with a number of endocrinologic conditions, hypertension, vascular
disease, high levels of blood cholesterol, low levels of high density
lipoprotein, drugs, neurogenic disorders, Peyronie's disease, priapism,
depression, alcohol ingestion, lack of sexual knowledge, poor sexual
techniques, inadequate interpersonal relationships or their
deterioration, and many chronic diseases, especially renal failure and
dialysis, have been demonstrated as risk factors. Vascular surgery is
also often a risk factor. Age appears to be a strong indirect risk
factor in that it is associated with an increased likelihood of direct
risk factors. Other factors require more extensive study. Smoking has an
adverse effect on erectile function by accentuating the effects of other
risk factors such as vascular disease or hypertension. To date,
vasectomy has not been associated with an increased risk of erectile
dysfunction other than causing an occasional psychological reaction that
could then have a psychogenic influence. Accurate risk factor
identification and characterization are essential for concerted efforts
at prevention of erectile dysfunction.
Prevention
Although erectile dysfunction increases progressively with age, it is
not an inevitable consequence of aging. Knowledge of the risk factors
can guide prevention strategies. Specific antihypertensive,
antidepressant, and antipsychotic drugs can be chosen to lessen the risk
of erectile failure. Published lists of prescription drugs that may
impair erectile functioning often are based on reports implicating a
drug without systematic study. Such studies are needed to confirm the
validity of these suggested associations. In the individual patient, the
physician can modify the regimen in an effort to resolve the erectile
problem.
It is important that physicians and other health care providers treating
patients for chronic conditions periodically inquire into the sexual
functioning of their patients and be prepared to offer counsel for those
who experience erectile difficulties. Lack of sexual knowledge and
anxiety about sexual performance are common contributing factors to
erectile dysfunction. Education and reassurance may be helpful in
preventing the cascade into serious erectile failure in individuals who
experience minor erectile difficulty due to medications or common
changes in erectile functioning associated with chronic illnesses or
with aging.
WHAT DIAGNOSTIC INFORMATION SHOULD BE OBTAINED IN ASSESSMENT OF THE
IMPOTENT PATIENT? WHAT CRITERIA SHOULD BE EMPLOYED TO DETERMINE WHICH
TESTS ARE INDICATED FOR A PARTICULAR PATIENT?
The appropriate evaluation of all men with erectile dysfunction should
include a medical and detailed sexual history (including practices and
techniques), a physical examination, a psycho-social evaluation, and
basic laboratory studies. When available, a multidisciplinary approach
to this evaluation may be desirable. In selected patients, further
physiologic or invasive studies may be indicated. A sensitive sexual
history, including expectations and motivations, should be obtained from
the patient (and sexual partner whenever possible) in an interview
conducted by an interested physician or another specially trained
professional. A written patient questionnaire may be helpful but is not
a substitute for the interview. The sexual history is needed to
accurately define the patient's specific complaint and to distinguish
between true erectile dysfunction, changes in sexual desire, and
orgasmic or ejaculatory disturbances. The patient should be asked
specifically about perceptions of his erectile dysfunction, including
the nature of onset, frequency, quality, and duration of erections; the
presence of nocturnal or morning erections; and his ability to achieve
sexual satisfaction. Psychosocial factors related to erectile
dysfunction should be probed, including specific situational
circumstances, performance anxiety, the nature of sexual relationships,
details of current sexual techniques, expectations, motivation for
treatment, and the presence of specific discord in the patient's
relationship with his sexual partner. The sexual partner's own
expectations and perceptions should also be sought since they may have
important bearing on diagnosis and treatment recommendations.
The general medical history is important in identifying specific risk
factors that may account for or contribute to the patient's erectile
dysfunction. These include vascular risk factors such as hypertension,
diabetes, smoking, coronary artery disease, peripheral vascular
disorders, pelvic trauma or surgery, and blood lipid abnormalities.
Decreased sexual desire or history suggesting a hypogonadal state could
indicate a primary endocrine disorder. Neurologic causes may include a
history of diabetes mellitus or alcoholism with associated peripheral
neuropathy. Neurologic disorders such as multiple sclerosis, spinal
injury, or cerebrovascular accidents are often obvious or well defined
prior to presentation. It is essential to obtain a detailed medication
and illicit drug history since an estimated 25 percent of cases of
erectile dysfunction may be attributable to medications for other
conditions. Past medical history can reveal important causes of erectile
dysfunction, including radical pelvic surgery, radiation therapy,
Peyronie's disease, penile or pelvic trauma, prostatitis, priapism, or
voiding dysfunction. Information regarding prior evaluation or treatment
for "impotence" should be obtained. A detailed sexual history, including
current sexual techniques, is important in the general history obtained.
It is also important to determine if there have been previous
psychiatric illnesses such as depression or neuroses.
Physical examination should include the assessment of male secondary sex
characteristics, femoral and lower extremity pulses, and a focused
neurologic examination including perianal sensation, anal sphincter
tone, and bulbocavernosus reflex. More extensive neurologic tests,
including dorsal nerve conduction latencies, evoked potential
measurements, and corpora cavernosal electromyography lack normative
(control) data and appear at this time to be of limited clinical value.
Examination of the genitalia includes evaluation of testis size and
consistency, palpation of the shaft of the penis to determine the
presence of Peyronie's plaques, and a digital rectal examination of the
prostate with assessment of anal sphincter tone.
Endocrine evaluation consisting of a morning serum testosterone is
generally indicated. Measurement of serum prolactin may be indicated. A
low testosterone level merits repeat measurement together with
assessment of luteinizing hormone (LH), follicle-stimulating hormone
(FSH), and prolactin levels. Other tests may be helpful in excluding
unrecognized systemic disease and include a complete blood count,
urinalysis, creatinine, lipid profile, fasting blood sugar, and thyroid
function studies.
Although not indicated for routine use, nocturnal penile tumescence
(NPT) testing may be useful in the patient who reports a complete
absence of erections (exclusive of nocturnal "sleep" erections) or when
a primary psychogenic etiology is suspected. Such testing should be
performed by those with expertise and knowledge of its interpretation,
pitfalls, and usefulness. Various methods and devices are available for
the evaluation of nocturnal penile tumescence, but their clinical
usefulness is restricted by limitations of diagnostic accuracy and
availability of normative data. Further study regarding standardization
of NPT testing and its general applicability is indicated.
After the history, physical examination, and laboratory testing, a
clinical impression can be obtained of a primarily psychogenic, organic,
or mixed etiology for erectile dysfunction. Patients with primary or
associated psychogenic factors may be offered further psychologic
evaluation, and patients with endocrine abnormalities may be referred to
an endocrinologist to evaluate the possibility of a pituitary lesion or
hypogonadism. Unless previously diagnosed, suspicion of neurologic
deficit may be further assessed by complete neurologic evaluation. No
further diagnostic tests appear necessary for those patients who favor
noninvasive treatment (e.g., vacuum constrictive devices, or
pharmacologic injection therapy). Patients who do not respond
satisfactorily to these noninvasive treatments may be candidates for
penile implant surgery or further diagnostic testing for possible
additional invasive therapies.
A rigid or nearly rigid erectile response to intracavernous injection of
pharmacologic test doses of a vasodilating agent (see below) indicates
adequate arterial and veno-occlusive function. This suggests that the
patient may be a suitable candidate for a trial of penile injection
therapy. Genital stimulation may be of use in increasing the erectile
response in this setting. This diagnostic technique also may be used to
differentiate a vascular from a primarily neuropathic or psychogenic
etiology. Patients who have an inadequate response to intracavernous
pharmacologic injection may be candidates for further vascular testing.
It should be recognized, however, that failure to respond adequately may
not indicate vascular insufficiency but can be caused by patient anxiety
or discomfort. The number of patients who may benefit from more
extensive vascular testing is small, but includes young men with a
history of significant perineal or pelvic trauma, who may have anatomic
arterial blockage (either alone or with neurologic deficit) to account
for erectile dysfunction.
Studies to further define vasculogenic disorders include pharmacologic
duplex grey scale/color ultrasonography, pharmacologic dynamic infusion
cavernosometry/ cavernosography, and pharmacologic pelvic/penile
angiography. Cavernosometry, duplex ultrasonography, and angiography
performed either alone or in conjunction with intracavernous
pharmacologic injection of vasodilator agents rely on complete arterial
and cavernosal smooth muscle relaxation to evaluate arterial and
veno-occlusive function. The clinical effectiveness of these invasive
studies is severely limited by several factors, including the lack of
normative data, operator dependence, variable interpretation of results,
and poor predictability of therapeutic outcomes of arterial and venous
surgery. At the present time these studies might best be done in
referral centers with specific expertise and interest in investigation
of the vascular aspects of erectile dysfunction. Further clinical
research is necessary to standardize methodology and interpretation, to
obtain control data on normals (as stratified according to age), and to
define what constitutes normality in order to assess the value of these
tests in their diagnostic accuracy and in their ability to predict
treatment outcome in men with erectile dysfunction.
WHAT ARE THE EFFICACIES AND RISKS OF BEHAVIORAL, PHARMACOLOGICAL,
SURGICAL, AND OTHER TREATMENTS FOR IMPOTENCE? WHAT SEQUENCES AND/OR
COMBINATION OF THESE INTERVENTIONS ARE APPROPRIATE? WHAT MANAGEMENT
TECHNIQUES ARE APPROPRIATE WHEN TREATMENT IS NOT EFFECTIVE OR INDICATED?
General Considerations
Because of the difficulty in defining the clinical entity of erectile
dysfunction, there have been a variety of entry criteria for patients in
therapeutic trials. Similarly, the ability to assess efficacy of
therapeutic interventions is impaired by the lack of clear and
quantifiable criteria of erectile dysfunction. General considerations
for treatment follow:
•Psychotherapy and/or behavioral therapy may be useful for some patients
with erectile dysfunction without obvious organic cause, and for their
partners. These may also be used as an adjunct to other therapies
directed at the treatment of organic erectile dysfunction. Outcome data
from such therapy, however, have not been well-documented or quantified,
and additional studies along these lines are indicated.•Efficacy of
therapy may be best achieved by inclusion of both partners in treatment
plans.•Treatment should be individualized to the patient's desires and
expectations.•Even though there are several effective treatments
currently available, long-term efficacy is in general relatively low.
Moreover, there is a high rate of voluntary cessation of treatment for
all currently popular forms of therapy for erectile dysfunction. Better
understanding of the reasons for each of these phenomena is needed.
Psychotherapy and Behavioral Therapy
Psychosocial factors are important in all forms of erectile dysfunction.
Careful attention to these issues and attempts to relieve sexual
anxieties should be a part of the therapeutic intervention for all
patients with erectile dysfunction. Psychotherapy and/or behavioral
therapy alone may be helpful for some patients in whom no organic cause
of erectile dysfunction is detected. Patients who refuse medical and
surgical interventions also may be helped by such counseling. After
appropriate evaluation to detect and treat coexistent problems such as
issues related to the loss of a partner, dysfunctional relationships,
psychotic disorders, or alcohol and drug abuse, psychological treatment
focuses on decreasing performance anxiety and distractions and on
increasing a couple's intimacy and ability to communicate about sex.
Education concerning the factors that create normal sexual response and
erectile dysfunction can help a couple cope with sexual difficulties.
Working with the sexual partner is useful in improving the outcome of
therapy. Psychotherapy and behavioral therapy have been reported to
relieve depression and anxiety as well as to improve sexual function.
However, outcome data of psychological and behavioral therapy have not
been quantified, and evaluation of the success of specific techniques
used in these treatments is poorly documented. Studies to validate their
efficacy are therefore strongly indicated.
Medical Therapy
An initial approach to medical therapy should consider reversible
medical problems that may contribute to erectile dysfunction. Included
in this should be assessment of the possibility of medication-induced
erectile dysfunction with consideration for reduction of polypharmacy
and/or substitution of medications with lower probability of inducing
erectile dysfunction.
For some patients with an established diagnosis of testicular failure
(hypogonadism), androgen replacement therapy may sometimes be effective
in improving erectile function. A trial of androgen replacement may be
worthwhile in men with low serum testosterone levels if there are no
other contraindications. In contrast, for men who have normal
testosterone levels, androgen therapy is inappropriate and may carry
significant health risks, especially in the situation of unrecognized
prostate cancer. If androgen therapy is indicated, it should be given in
the form of intramuscular injections of testosterone enanthate or
cypionate. Oral androgens, as currently available, are not indicated.
For men with hyperprolactinemia, bromocriptine therapy often is
effective in normalizing the prolactin level and improving sexual
function. A wide variety of other substances taken either orally or
topically have been suggested to be effective in treating erectile
dysfunction. Most of these have not been subjected to rigorous clinical
studies and are not approved for this use by the Food and Drug
Administration (FDA). Their use should therefore be discouraged until
further evidence in support of their efficacy and indicative of their
safety is available.
Intracavernosal Injection Therapy
Injection of vasodilator substances into the corpora of the penis has
provided a new therapeutic technique for a variety of causes of erectile
dysfunction. The most effective and well-studied agents are papaverine,
phentolamine, and prostaglandin E[sub 1]. These have been used either
singly or in combination. Use of these agents occasionally causes
priapism (inappropriately persistent erections). This appears to have
been seen most commonly with papaverine. Priapism is treated with
adrenergic agents, which can cause life-threatening hypertension in
patients receiving monoamine oxidase inhibitors. Use of the penile
vasodilators also can be problematic in patients who cannot tolerate
transient hypotension, those with severe psychiatric disease, those with
poor manual dexterity, those with poor vision, and those receiving
anticoagulant therapy. Liver function tests should be obtained in those
being treated with papaverine alone. Prostaglandin E[sub 1] can be used
together with papaverine and phentolamine to decrease the incidence of
side effects such as pain, penile corporal fibrosis, fibrotic nodules,
hypotension, and priapism. Further study of the efficacy of multitherapy
versus monotherapy and of the relative complications and safety of each
approach is indicated. Although these agents have not received FDA
approval for this indication, they are in widespread clinical use.
Patients treated with these agents should give full informed consent.
There is a high rate of patient dropout, often early in the treatment.
Whether this is related to side effects, lack of spontaneity in sexual
relations, or general loss of interest is unclear. Patient education and
followup support might improve compliance and lessen the dropout rate.
However, the reasons for the high dropout rate need to be determined and
quantified.
Vacuum/Constrictive Devices
Vacuum constriction devices may be effective at generating and
maintaining erections in many patients with erectile dysfunction and
these appear to have a low incidence of side effects. As with
intracavernosal injection therapy, there is a significant rate of
patient dropout with these devices, and the reasons for this phenomenon
are unclear. The devices are difficult for some patients to use, and
this is especially so in those with impaired manual dexterity. Also,
these devices may impair ejaculation, which can then cause some
discomfort. Patients and their partners sometimes are bothered by the
lack of spontaneity in sexual relations that may occur with this
procedure. The patient is sometimes also bothered by the general
discomfort that can occur while using these devices. Partner involvement
in training with these devices may be important for successful outcome,
especially in regard to establishing a mutually satisfying level of
sexual activity.
Vascular Surgery
Surgery of the penile venous system, generally involving venous
ligation, has been reported to be effective in patients who have been
demonstrated to have venous leakage. However, the tests necessary to
establish this diagnosis have been incompletely validated; therefore, it
is difficult to select patients who will have a predictably good
outcome. Moreover, decreased effectiveness of this approach has been
reported as longer term followups have been obtained. This has tempered
enthusiasm for these procedures, which are probably therefore best done
in an investigational setting in medical centers by surgeons experienced
in these procedures and their evaluation.
Arterial revascularization procedures have a very limited role (e.g., in
congenital or traumatic vascular abnormality) and probably should be
restricted to the clinical investigation setting in medical centers with
experienced personnel. All patients who are considered for vascular
surgical therapy need to have appropriate preoperative evaluation, which
may include dynamic infusion pharmaco-cavernosometry and cavernosography
(DICC), duplex ultrasonography, and possibly arteriography. The
indications for and interpretations of these diagnostic procedures are
incompletely standardized; therefore, difficulties persist with using
these techniques to predict and assess the success of surgical therapy,
and further investigation to clarify their value and role in this regard
is indicated.
Penile Prostheses
Three forms of penile prostheses are available for patients who fail
with or refuse other forms of therapy: semirigid, malleable, and
inflatable. The effectiveness, complications, and acceptability vary
among the three types of prostheses, with the main problems being
mechanical failure, infection, and erosions. Silicone particle shedding
has been reported, including migration to regional lymph nodes; however,
no clinically identifiable problems have been reported as a result of
the silicone particles. There is a risk of the need for reoperation with
all devices. Although the inflatable prostheses may yield a more
physiologically natural appearance, they have had a higher rate of
failure requiring reoperation. Men with diabetes mellitus, spinal cord
injuries, or urinary tract infections have an increased risk of
prosthesis-associated infection. This form of treatment may not be
appropriate in patients with severe penile corporal fibrosis, or severe
medical illness. Circumcision may be required for patients with phimosis
and balanitis.
Staging of Treatment
The patient and partner must be well informed about all therapeutic
options including their effectiveness, possible complications, and
costs. As a general rule, the least invasive or dangerous procedures
should be tried first. Psychotherapy and behavioral treatments and
sexual counseling alone or in conjunction with other treatments may be
used in all patients with erectile dysfunction who are willing to use
this form of treatment. In patients in whom psychogenic erectile
dysfunction is suspected, sexual counseling should be offered first.
Invasive therapy should not be the primary treatment of choice. If
history, physical, and screening endocrine evaluations are normal and
nonpsychogenic erectile dysfunction is suspected, either vacuum devices
or intracavernosal injection therapy can be offered after discussion
with the patient and his partner. These latter two therapies may also be
useful when combined with psychotherapy in those with psychogenic
erectile dysfunction in whom psychotherapy alone has failed. Since
further diagnostic testing does not reliably establish specific
diagnoses or predict outcomes of therapy, vacuum devices or
intracavernosal injections often are applied to a broad spectrum of
etiologies of male erectile dysfunction.
The motivation and expectations of the patient and his partner and
education of both are critical in determining which therapy is chosen
and in optimizing its outcome. If single therapy is ineffective,
combining two or more forms of therapy may be useful. Penile prostheses
should be placed only after patients have been carefully screened and
informed. Vascular surgery should be undertaken only in the setting of
clinical investigation and extensive clinical experience. With any form
of therapy for erectile dysfunction, long-term followup by health
professionals is required to assist the patient and his partner with
adjustment to the therapeutic intervention. This is particularly true
for intracavernosal injection and vacuum constriction therapies.
Followup should include continued patient education and support in
therapy, careful determination of reasons for cessation of therapy if
this occurs, and provision of other options if earlier therapies are
unsuccessful.
WHAT STRATEGIES ARE EFFECTIVE IN IMPROVING PUBLIC AND PROFESSIONAL
KNOWLEDGE ABOUT IMPOTENCE?
Despite the accumulation of a substantial body of scientific information
about erectile dysfunction, large segments of the public -- as well as
the health professions -- remain relatively uninformed, or -- even worse
-- misinformed, about much of what is known. This lack of information,
added to a pervasive reluctance of physicians to deal candidly with
sexual matters, has resulted in patients being denied the benefits of
treatment for their sexual concerns. Although they might wish doctors
would ask them questions about their sexual lives, patients, for their
part, are too often inhibited from initiating such discussions
themselves. Improving both public and professional knowledge about
erectile dysfunction will serve to remove those barriers and will foster
more open communication and more effective treatment of this condition.
Strategies for Improving Public Knowledge
To a significant degree, the public, particularly older men, is
conditioned to accept erectile dysfunction as a condition of progressive
aging for which little can be done. In addition, there is considerable
inaccurate public information regarding sexual function and dysfunction.
Often, this is in the form of advertisements in which enticing promises
are made, and patients then become even more demoralized when promised
benefits fail to materialize. Accurate information on sexual function
and the management of dysfunction must be provided to affected men and
their partners. They also must be encouraged to seek professional help,
and providers must be aware of the embarrassment and/or discouragement
that may often be reasons why men with erectile dysfunction avoid
seeking appropriate treatment.
To reach the largest audience, communications strategies should include
informative and accurate newspaper and magazine articles, radio and
television programs, as well as special educational programs in senior
centers. Resources for accurate information regarding diagnosis and
treatment options also should include doctors' offices, unions,
fraternal and service groups, voluntary health organizations, State and
local health departments, and appropriate advocacy groups. Additionally,
since sex education courses in schools uniformly address erectile
function, the concept of erectile dysfunction can easily be communicated
in these forums as well.
Strategies for Improving Professional Knowledge
•Provide wide distribution of this statement to physicians and other
health professionals whose work involves patient contact.•Define a
balance between what specific information is needed by the medical and
general public and what is available, and identify what treatments are
available.•Promote the introduction of courses in human sexuality into
the curricula of graduate schools for all health care professionals.
Because sexual well-being is an integral part of general health,
emphasis should be placed on the importance of obtaining a detailed
sexual history as part of every medical history.•Encourage the inclusion
of sessions on diagnosis and management of erectile dysfunction in
continuing medical education courses.•Emphasize the desirability for an
interdisciplinary approach to the diagnosis and treatment of erectile
dysfunction. An integrated medical and psychosocial effort with
continuing contact with the patient and partner may enhance their
motivation and compliance with treatment during the period of sexual
rehabilitation.•Encourage the inclusion of presentations on erectile
dysfunction at scientific meetings of appropriate medical specialty
associations, State and local medical societies, and similar
organizations of other health professions.•Distribute scientific
information on erectile dysfunction to the news media (print, radio, and
television) to support their efforts to disseminate accurate information
on this subject and to counteract misleading news reports and false
advertising claims.•Promote public service announcements, lectures, and
panel discussions on both commercial and public radio and television on
the subject of erectile dysfunction.
WHAT ARE THE NEEDS FOR FUTURE RESEARCH?
This consensus development conference on male erectile dysfunction has
provided an overview of current knowledge on the prevalence, etiology,
pathophysiology, diagnosis, and management of this condition. The
growing individual and societal awareness and open acknowledgment of the
problem have led to increased interest and resultant explosion of
knowledge in each of these areas. Research on this condition has
produced many controversies, which also were expressed at this
conference. Numerous questions were identified that may serve as foci
for future research directions. These will depend on the development of
precise agreement among investigators and clinicians in this field on
the definition of what constitutes erectile dysfunction, and what
factors in its multifaceted nature contribute to its expression. In
addition, further investigation of these issues will require
collaborative efforts of basic science investigators and clinicians from
the spectrum of relevant disciplines and the rigorous application of
appropriate research principles in designing studies to obtain further
knowledge and to promote understanding of the various aspects of this
condition.
The needs and directions for future research can be considered as
follows:
•Development of a symptom score sheet to aid in the standardization of
patient assessment and treatment outcome.•Development of a staging
system that may permit quantitative and qualitative classification of
erectile dysfunction.•Studies on perceptions and expectations associated
with racial, cultural, ethnic, and societal influences on what
constitutes normal male erectile function and how these same factors may
be responsible for the development and/or perception of male erectile
dysfunction.•Studies to define and characterize what is normal erectile
function, possibly as stratified by age.•Additional basic research on
the physiological and biochemical mechanisms that may underlie the
etiology, pathogenesis, and response to treatment of the various forms
of erectile dysfunction.•Epidemiological studies directed at the
prevalence of male erectile dysfunction and its medical and
psychological correlates, particularly in the context of possible
racial, ethnic, socioeconomic, and cultural variability.•Additional
studies of the mechanisms by which risk factors may produce erectile
dysfunction.•Studies of strategies to prevent male erectile dysfunction.
•Randomized clinical trials assessing the effectiveness of specific
behavioral, mechanical, pharmacologic, and surgical treatments, either
alone or in combination.•Studies on the specific effects of hormones
(especially androgens) on male sexual function; determination of the
frequency of endocrine causes of erectile dysfunction (e.g.,
hypogonadism and hyperprolactinemia) and the rates of success of
appropriate hormonal therapy.•Longitudinal studies in well-specified
populations; evaluation of alternative approaches for the systematic
assessment of men with erectile dysfunction; cost-effectiveness studies
of diagnostic and therapeutic approaches; formal outcomes research of
the various approaches to the assessment and treatment of this
condition.•Social/psychological studies of the impact of erectile
dysfunction on subjects, their partners, and their interactions, and
factors associated with seeking care.•Development of new therapies,
including pharmacologic agents, and with emphasis on oral agents, that
may address the cause of male erectile dysfunction with greater
specificity.•Long-term followup studies to assess treatment effects,
patient compliance, and late adverse effects.•Studies to characterize
the significance of erectile function and dysfunction in women.
CONCLUSIONS
•The term "erectile dysfunction" should replace the term
"impotence" to
characterize the inability to attain and/or maintain penile erection
sufficient for satisfactory sexual performance.•The likelihood of
erectile dysfunction increases progressively with age but is not an
inevitable consequence of aging. Other age-related conditions increase
the likelihood of its occurrence.•Erectile dysfunction may be a
consequence of medications taken for other problems or a result of drug
abuse.•Embarrassment of patients and the reluctance of both patients and
health care providers to discuss sexual matters candidly contribute to
underdiagnosis of erectile dysfunction.•Contrary to present public and
professional opinion, many cases of erectile dysfunction can be
successfully managed with appropriately selected therapy.•Men with
erectile dysfunction require diagnostic evaluations and treatments
specific to their circumstances. Patient compliance as well as patient
and partner desires and expectations are important considerations in the
choice of a particular treatment approach. A multidisciplinary approach
may be of great benefit in defining the problem and arriving at a
solution.•The development of methods to quantify the degree of erectile
dysfunction objectively would be extremely useful in the assessment both
of the problem and of treatment outcomes.•Education of physicians and
other health professionals in aspects of human sexuality is currently
inadequate, and curriculum development is urgently needed.•Education of
the public on aspects of sexual dysfunction and the availability of
successful treatments is essential; media involvement in this effort is
an important component. This should be combined with information
designed to expose "quack remedies" and protect men and their partners
from economic and emotional losses.•Important information on many
aspects of erectile dysfunction is lacking; major research efforts are
essential to the improvement of our understanding of the appropriate
diagnostic assessments and treatments of this condition.•Erectile
dysfunction is an important public health problem deserving of increased
support for basic science investigation and applied research.
CONSENSUS DEVELOPMENT PANEL
Michael J. Droller, M.D.*
Panel and Conference Chairperson
Professor and Chairman
Department of Urology
The Mount Sinai Medical Center
New York, New York
James R. Anderson, Ph.D.
Professor and Chair Department of Preventive and Societal Medicine
University of Nebraska Medical Center
Omaha, Nebraska
John C. Beck, M.D.
Director Professor of Medicine
Geriatrics Multicampus Program of Geriatric Medicine and Gerontology
UCLA School of Medicine
Los Angeles, California
William J. Bremner, M.D., Ph.D.
Chief of Medicine
Seattle Veterans' Affairs Medical Center
Professor and Vice-Chairman of Medicine
University of Washington
Seattle, Washington
Kurt Evans, M.D.
Chief
Department of Urology
Kaiser Permanente
Dallas, Texas
Mikel Gray, Ph.D., CURN
Clinical Uro Dynamics Adjunct Professor
Georgia State University School of Nursing
Alpharetta, Georgia
Arthur H. Keeney, III
Executive Director
American Foundation for Urologic Disease
Baltimore, Maryland
Philip J. Lanzisera, Ph.D.
Director of Psychology Internship Program
Department of Psychiatry
Henry Ford Health Sciences Center
Detroit, Michigan
Winston C. Liao, Ph.D.
Associate Program Director
Center for Epidemiologic and Medical Studies
Research Triangle Institute
Research Triangle Park, North Carolina
David W. Richardson, M.D.
Professor of Medicine
Department of Cardiology
Medical College of Virginia
Richmond, Virginia
Thomas J. Rohner, Jr., M.D.
Professor of Surgery (Urology)
Chief
Division of Urology
Pennsylvania State University College of Medicine
Milton S. Hershey Medical Center
Hershey, Pennsylvania
Linda D. Shortliffe, M.D.
Associate Professor and Chief, Pediatric Urology
Department of Urology
Packard Children's Hospital at Stanford
Stanford University Medical School
Stanford, California
William R. Turner, M.D.
Professor and Chairman
Department of Urology
Medical University of South Carolina, Charleston
Charleston, South Carolina
Arthur Zitrin, M.D.
Professor of Psychiatry
Associate Dean
New York University School of Medicine
New York, New York
SPEAKERS
Stanley E. Althof, Ph.D.
"Choosing Among Contemporary Alternatives: Self-Injection Versus Vacuum
Pump Therapy"
Alan H. Bennett, M.D.
"When to Perform Venous Studies in the Impotent Patient"
Gregory Broderick, M.D.
"Drug-Induced Male Sexual Dysfunction"
Irwin Goldstein, M.D.
"The Effect of Age-Related Diseases on the Development of Impotence"
"The Venous System in the Diagnosis of Erectile Impotence"
"Intracavernosal Therapy for Erectile Impotence"
Helen Singer Kaplan, Ph.D.
"The Psychological Evaluation of the Impotent Male"
Stanley G. Korenman, M.D.
"The Relationship Between Impotence and Aging"
Ronald W. Lewis, M.D.
"Penile Prosthesis"
Tom F. Lue, M.D.
"Anatomy and Physiology of Normal and Abnormal Erection"
"The Diagnosis of Arterial-Related Impotence"
"Peyronie's Disease"
William H. Masters, M.D.
"Introduction: A History of the Diagnosis and Treatment of Impotence"
John B. McKinlay, Ph.D.
"The Prevalence and Demographics of Impotence"
Arnold Melman, M.D.
"The Argument Against the Utilization of Arterial Studies in the
Diagnosis of Impotence"
Drogo K. Montague, M.D.
"General Diagnostic Procedures Employed in the Diagnosis of Erectile
Impotence"
Alvaro Morales, M.D., F.R.C.S.(C)
"Hormonal Studies in the Evaluation of the Impotent Man"
"The Medical Management of Impotence"
David Osborne, Ph.D.
"Behavioral Intervention in the Treatment of Erectile Impotence"
Jacob Rajfer, M.D.
"Nitric Oxide and Erections"
John Rowe, M.D.
"The Prevention of Erectile Impotence The Need for Education"
Inigo Saenz de Tejada, M.D.
"Vascular Physiology of Erection"
Michael H.H. Sohn, M.D.
"Vascular Procedures for the Treatment of Erectile Impotence"
William D. Steers, M.D.
"Neurophysiology of Penile Erection"
Leonore Tiefer, Ph.D.
"Nomenclature"
"Partner Issues in Diagnosis and Treatment"
Gorm Wagner, M.D., Ph.D.
"Neurologic Evaluation of the Impotent Male"
PLANNING COMMITTEE
Leroy M. Nyberg, Ph.D., M.D.
Planning Committee Chairperson
Director
Urology Program Division of Kidney, Urologic, and Hematologic Diseases
National Institute of Diabetes and Digestive and Kidney Diseases
National Institutes of Health
Bethesda, Maryland
Alan H. Bennett, M.D.
Professor of Surgery
Head, Division of Urological Surgery
Albany Medical Center Hospital and Albany Medical College
Albany, New York
Benjamin T. Burton, Ph.D.
Associate Director for Disease Prevention and Technology Transfer
National Institute of Diabetes and Digestive and Kidney Diseases
National Institutes of Health
Bethesda, Maryland
Michael J. Droller, M.D.
Conference and Panel Chairperson
Professor and Chairman
Department of Urology
Mount Sinai Medical Center
New York, New York
Jerry M. Elliott
Program Analyst
Office of Medical Applications of Research
National Institutes of Health
Bethesda, Maryland
John H. Ferguson, M.D.
Director
Office of Medical Applications of Research
National Institutes of Health
Bethesda, Maryland
Willis R. Foster, M.D.
Senior Staff Physician
Office of Disease Prevention and Technology Transfer
National Institute of Diabetes and Digestive and Kidney Diseases
National Institutes of Health
Bethesda, Maryland
Jean Fourcroy, M.D.
Medical Officer
Division of Metabolism and Endocrinology
Drug Products Center for Drug Evaluation and Research
Food and Drug Administration
Rockville, Maryland
Irwin Goldstein, M.D.
Professor of Urology
Department of Urology
Boston University School of Medicine
Boston, Massachusetts
William H. Hall
Director of Communications
Office of Medical Applications of Research
National Institutes of Health
Bethesda, Maryland
F. Terry Hambrecht, M.D.
Head
Neural Prosthesis Program
Division of Fundamental Neurosciences
National Institute of Neurological Disorders and Stroke
National Institutes of Health
Bethesda, Maryland
Mary M. Harris
Writer/Editor
Office of Health Research Reports
National Institute of Diabetes and Digestive and Kidney Diseases
National Institutes of Health
Bethesda, Maryland
Stuart S. Howards, M.D.
Professor of Urology
Department of Urology
University of Virginia Hospital
Charlottesville, Virginia
Mark D. Kramer
Chief
Urology and Lithotripsy Devices Branch
Food and Drug Administration
Rockville, Maryland
Tom F. Lue, M.D.
Professor
Department of Urology
University of California at San Francisco
San Francisco, California
William H. Masters, M.D.
Masters & Johnson Institute
St. Louis, Missouri
Arnold Melman, M.D.
Professor and Chairman
Department of Urology
Albert Einstein College of Medicine
Montefiore Medical Center
Bronx, New York
Stanley L. Slater, M.D.
Acting Deputy Associate Director for Geriatrics
National Institute on Aging
National Institutes of Health
Bethesda, Maryland
Donna L. Vogel, M.D., Ph.D.
Head, Reproductive Medicine Unit
Reproductive Sciences Branch
National Institute of Child Health and Human Development
National Institutes of Health
Bethesda, Maryland
CONFERENCE SPONSORS
National Institute of Diabetes and Digestive and Kidney Diseases
Phillip Gorden, M.D.
Director
National Institute on Aging
Gene Cohen, M.D.
Acting Director
National Institute of Neurological Disorders and Stroke
Murray Goldstein, D.O.
Director
Office of Medical Applications of Research
John H. Ferguson, M.D.
Director
ABOUT THE NIH CONSENSUS DEVELOPMENT PROGRAM
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