The term "impotence" 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. 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. 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.
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.
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.
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.
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.
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.
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.
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.
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.
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:
Testosterone replacement therapy is one prescription option for men whose natural testosterone level is not within the normal range, but its serious potential side effects call for a physician's supervision. For those with an impotence problem that isn't caused by low testosterone levels, the "Caverject" injection may be the answer.
Caverject is self-injected into the penis shortly before sexual intercourse. The drug creates an erection by relaxing the smooth muscle tissue and dilating the major artery in the penis, which enhances the blood flow to the penis. The drug provides an alternative to devices previously approved by FDA. A vacuum device involves placing a cylinder-like device and attached pump over the penis. By using the pump, blood is drawn into the penis, creating an erection. A constriction band is then placed at the base of the penis to maintain erection. A second treatment option, the penile implant, involves the surgical placement of cylinders in the penis and is available in a variety of designs.
At this time, sildenafil (Viagra) is the only oral drug to successfully treat erectile dysfunction in clinical studies. This drug works by increasing the concentration of cyclic guanosine monophosphate in the penis. This natural chemical causes the blood vessels to dilate (widen), which increases the blood flow to the penis. Sildenafil is not recommended for men who have angina and are taking medications that help to widen the coronary arteries (including all nitrate [nitroglycerin]-containing drugs); the combination of these drugs can lower blood pressure to life-threateningly low levels. Sildenafil has also been reported to cause priapism, a rare but serious side effect that causes an erection to last for more than 4 hours. If this occurs, seek immediate medical attention.
There is no proof that ginseng, rhinoceros horn, or oysters have an effect on human sexual reaction. But might some foods and OTC drugs eventually be proven to affect sexual appetite? Some big obstacles exist to answering this question. The placebo effect is one scientific stumbling block.
Because the psychological complications are absent in animals, some studies have been done on the effect of certain drugs on animals' sexual activity. One substance that was tested extensively in animals is yohimbine. Obtained from the bark of an African tree, yohimbine has been used for centuries in Africa and West India for its supposed aphrodisiac properties. It supposedly works by stimulating the nerve centers in the spine that control erection. FDA called the res ults of preliminary animal studies "encouraging, " but animal studies cannot be relied on to show the effectiveness of the drug in humans.
A good diet and a regular exercise program are a more dependable path to better sex than are goats' eyes, deer sperm, and frogs' legs. A good mental state is equally important.
Maybe the wishful search for a cure-all drug should be abandoned in favor of an easier, more reliable mechanism: the erotic stimulation of one's own imagination. To quote renowned sex expert "Dr. Ruth" Westheimer, Ed.D.: "The most important sex organ lies between the ears."