Sexuality is a basic human need that exists throughout life in one form or another and is a significant component to quality of life of many older individuals. Although 70% of adult patients in a large sample study considered sexual matters to be an appropriate topic for a general clinician or geriatrician to discuss, sexual problems are noted in less than 2% of primary care physicians’ notes. It is not easy to find physicians and other health care providers who are knowledgeable about sexuality in general and sexuality among the aging population in particular. Sexuality and sexual function in the aging female is addressed in Chapter 47. Sexuality, sexual function, and dysfunction in the aging male will be addressed in the first part of this chapter, with the second part being devoted to androgen replacement therapy in the older man.

Sexual Behaviors

Idealized societal concepts of older people do not include sex or the facility for sexual function. A poll conducted by the National Council on Aging, regarding attributes of people aged 65 years or older, reported that older persons were frequently thought of as being “warm and friendly” (74% of respondents) or “wise from experience” (70% of respondents), but being “sexually active” was only attributed to older persons by 5% of the survey respondents. Yet epidemiologic studies of sexuality and aging, such as the Duke Longitudinal Studies, the Massachusetts Male Aging Study, and, most recently, the University of Chicago study, report many older adults are sexually active. Sexual expression can encompass many forms, including sexual intercourse, oral sex, masturbation, intimacy, physical appearance, erotic stimuli (reading, movies) and fantasies (daydreams), but most study data involve the first three components.

Figure 49-1 depicts the prevalence of male sexual activity with a partner based on a probability sampling of 3000 U.S. adults aged 57 to 85 years. The likelihood of sexual activity with a partner declined with age, but nearly 39% of men aged 75 to 85 years reported sexual activity with a partner within the previous 12 months, with 54% of these sexually active 75- to 85-year-old men reporting sex at least two to three times a month.

In addition to partner availability, there are other factors that affect sexual activity in older adults. Health status has a strong influence. Diseases such as arthritis, especially when it involves the hips and pelvis, can affect sexual positions, endurance, and comfort. Urinary incontinence, with or without the need of urinary catheters, or the presence of ostomies can affect body image and may raise physical barriers to sexual activity. Chronic diseases, such as diabetes, stroke, or cardiovascular disease also will have significant impact, especially with regard to erectile function in the aging male, as will be discussed later. The effect of self-reported health status on the prevalence of sexual activity is shown in Figure 49-1. Older men across all age ranges who reported excellent or good health were more likely to be sexually active than men with fair or poor health. Medications also may have an impact on the level of sexual activity and function, particularly for men, as many medications can impact erectile function; this will be discussed in detail later in the chapter.

Changes in Male Sexual Physiology with Age

Overall there is a gradual slowing of sexual physical response time as men age. It takes more time to achieve sexual arousal, complete the sexual act, and become rearoused for further sexual activity. Table 49-1 lists the specific changes in the male sexual response cycle with age. Some of the changes have been shown to be impacted, at least in part, by low testosterone levels, while others are unaffected by hormone levels. The aging male may need reassurance that slowing of the sexual response is normal and predictable in order to avoid the fear and anxiety that may ensue without such information. Lengthening of the period of foreplay is one approach to adapting to these normal aging changes.

The Aging Male Homosexual

In the United States, there are about 3.5 million gay people aged 60 yrs and older. Older homosexual men have similar sexual problems as older heterosexual men, but may suffer additional problems of stress while trying to find a partner, especially if their living situation changes and they move into assisted living facilities or nursing homes. Specific organizations that address issues of aging gay and bisexual persons have formed across the country. Examples include Senior Action in the Gay Environment (SAGE) in the New York City area or Gay and Lesbians Older and Wiser (GLOW) in Ann Arbor, Michigan.

Unprotected sex occurs in approximately 10% of older homosexuals. Compared to younger homosexual men, older homosexual men get tested less often for sexually transmitted diseases, including testing for acquired immunodeficiency syndrome (AIDS). The incidence of AIDS is increasing in older men. Education about safe sex practices is important in the older population. Older males with a history of anal sex need to be regularly examined for anal cancer, as the prevalence increases in such persons.

Older male homosexuals should be encouraged to get advanced directives for health and to specifically designate their Durable Power of Attorney for Healthcare. This should facilitate the ability of their partners to make their health decisions.

Sex in Long-Term Care

Persons who live in nursing homes frequently have no opportunity for a private, social, or sexual life. Federal regulations issued in 1978 provide some right to privacy, but it is limited to married couples and to nursing homes that participate in federal Medicare and Medicaid programs. Specifically, the regulations state that (1) the nursing home residents have the right to share a room with their spouse when married residents live in one facility and both spouses consent and (2) the residents have the right to privacy during a visit with their spouse. These regulations are not uniformly enforced, however, and the majority of long-term care staff possess minimal understanding about how to deal with the sexuality of their nursing home residents. Education programs for nursing staff are important.

Additional barriers to sexual expression in long-term care include lack of a partner and physical or mental illness. Issues surrounding romantic liaisons between two unmarried residents in a nursing home can be especially problematic. Deciding about the competency of a cognitively impaired individual to consent to sexual interactions and the objection of adult children to a parent’s romantic liaison are just two examples of issues that can arise.

Sex and Dementia

Issues of sexuality are especially complex for those individuals who have cognitive impairment, as the diagnosis of dementia does not in itself determine in which domains a person is capable of making decisions. Some men with dementia become impotent, but others remain quite interested and capable, and a few older men with dementia become hypersexual. Physicians of demented male patients need to ask the spouse about sexual issues, as the wife may be embarrassed to reveal sexual difficulties. If the problems are placed in the context of dementia, it can assist with discussion of coping strategies. Nonsexual ways of expressing intimacy, such as touching, holding hands, and massages, might be suggested.

Categories of Male Sexual Dysfunction

Table 49-2 lists the major categories of sexual dysfunction in older men. Erectile dysfunction (ED) is the most prevalent of these categories. Erectile dysfunction (also called impotence) is defined as the inability to obtain and sustain a penile erection adequate for intercourse. Erectile dysfunction is not a result of aging per se, in that healthy older men do not lose the capacity for erections and ejaculation. However, it is a common problem for the aging man. Severe erectile dysfunction is estimated to be present in 20 million men in the United States. In the Massachusetts Male Aging Study, a community-based study of middle aged and older men, the reported incidence of any erectile dysfunction was 55% for men at age 60 years, and 65% for men at 70 years; the prevalence of total erectile dysfunction at age 70 years was 15%. In the University of Chicago study, about 45% of men aged 65 to 74 years reported having some erectile dysfunction.

Libido, the enthusiasm for sex, or sexual desire, is dependent on learned responses, general health-related quality of life, and, to some extent, serum testosterone levels. As will be discussed later in this chapter, testosterone levels decline in men with normal aging and some men may reach levels that are low enough to affect libido. However, testosterone replacement studies in hypogonadal men suggest that the level of testosterone needed to maintain libido is likely below the serum “normal” range for most men.

Performance anxiety is common in older men and often a result of equating masculinity with speed and magnitude of sexual activity. A man may become so preoccupied by his performance that his confidence and sexual capacity lessen, leading to erectile dysfunction. Depression and psychosocial stresses also are prevalent in older men and contribute to sexual problems. “Widower’s syndrome,” a condition in which a man fails to achieve erection after the death of spouse, is a reported entity.

Inability to reach climax or to resolve without ejaculation can occur. In the University of Chicago study, this occurred in about 16% in the 57- to 64-year age range, but increased to 33% in men aged 75 years and older.

Erectile Dysfunction

Physiology

To better understand how diseases and medications impact erectile function, it is important to have at least a cursory understanding of the physiology of penile erection. An erection of the penis is obtained in three ways: through local sensory stimulation of the penile shaft and glans penis, through visual or auditory stimuli, and spontaneously during rapid eye movement (REM) sleep. As men age, erection becomes more dependent on physical stimulation of the penis and less responsive to visual and other nongenital stimulation.

When the penis is flaccid, there is alpha-adrenergic-mediated vasoconstriction of arterioles and sinusoidal spaces of the corpora cavernosa. During erection, parasympathetic input results in vasodilatation, which leads to an increase in arterial blood flow and pressure in the cavernosal sinusoids, resulting in occlusion of the venous outflow system and penile erection. A number of neurotransmitters play a role in this process. Nitric oxide is released by penile endothelial cells and cavernous sinus nerves during sexual stimulation. This release of nitric oxide, along with other agents such as prostaglandins E1 and E2 and vasoactive intestinal peptide (VIP), results in smooth muscle relaxation within the corpora, which leads to an erection.

Etiologies

Table 49-3 lists the major etiologies of erectile dysfunction. The prevalence of the specific etiology depends on the type of reporting center (primary care, urology, endocrinology). Vascular disease, which includes both atherosclerotic arterial occlusive disease and corpora cavernosa venous leak, is the most common cause of erectile dysfunction across referral centers. The likely mechanism is that penile hypoxia leads to replacement of corpora smooth muscle by connective tissue, which results in impaired cavernosal expandability and inability to compress subtunical venules. Risk factors for vascular erectile dysfunction include the presence of diseases and habits associated with atherosclerosis, such as diabetes mellitus, hypertension, hyperlipidemia, and smoking. Trauma and Peyronnie’s disease can exacerbate the potential for corpora venous leakage. The penis is a high blood flow system during erectile function, so erectile dysfunction maybe an early sign of vascular inadequacy on the basis of atherosclerosis. Men who present with erectile dysfunction of vascular etiology are at very high risk of developing other vascular diseases, such as angina, myocardial infarction, or stroke, within 2 years of their diagnosis of erectile dysfunction. This risk remains even when controlled for current smoking or family history of myocardial infarction. Therefore, men with erectile dysfunction of suspected vascular etiology should be provided with appropriate screening and treatment for cardiovascular disease. Men with uncontrolled hypertension can develop erectile dysfunction as well, and erectile dysfunction can improve when the blood pressure normalizes. Men with mild to moderate hypertension need not restrict themselves sexually, but because systolic blood pressure can increase significantly with sexual activity, those with uncontrolled or severe hypertension should postpone sexual activity until blood pressure is controlled.

Neurological diseases, such as peripheral neuropathy, spinal cord injury, stroke, multiple sclerosis, temporal lobe epilepsy, and Parkinson’s disease all can cause erectile dysfunction. In men who develop multiple sclerosis, about half of them present initially with erectile dysfunction. In these men, erectile dysfunction maybe present for some amount of time, then disappear, and reappear at the next exacerbation. Men with stroke-related erectile dysfunction also tend to have ejaculatory problems.

Diabetes mellitus is the most common single disease to cause erectile dysfunction. The pathophysiology involves neuropathic, angiopathic, and general vascular changes. Although the severity of hyperglycemia has been suggested as a predictor of erectile dysfunction, there is little relation to the likelihood of erectile dysfunction in older men treated with oral agents or those needing insulin. Age, duration of diabetes, and other diabetic complications appear to be better predictors of erectile dysfunction than degree of hyperglycemia. Sometimes erectile dysfunction is the first symptom of diabetes mellitus, so all men who present with newly diagnosed erectile dysfunction should be evaluated for undiagnosed diabetes.

Significant other systemic diseases that can cause erectile dysfunction are renal failure and chronic obstructive pulmonary disease (COPD). Chronic renal failure impacts erectile function through effects on the vascular system and via the development of autonomic neuropathy. In addition, many men with end-stage renal disease are severely hypogonadal. Neither hemodialysis nor testosterone replacement in men with renal failure have been shown to improve erectile dysfunction. Men with COPD and low PaO2 have decreased cavernosal nitric oxide. Oxygen therapy may improve erectile function in some men with COPD.

Both hypercortisolemia and hyper- and hypothyroidism have been associated with hypoactive sexual desire and erectile dysfunction. Hypothyroidism also is associated with delayed ejaculation, with a prevalence of up to 64%; normalization of thyroid function frequently leads to improvement. Hyperthyroidism is associated with a 50% prevalence of premature ejaculation, which also improves with normalization of thyroid function.

Many studies have shown a clear association of erectile dysfunction with aging, but there have been no consistent correlations of erectile dysfunction in older men with low serum testosterone levels. In the Massachusetts Male Aging Study, where serum testosterone levels were measured throughout the study duration, of the men with no erectile dysfunction at baseline who were then followed up 8 years later, 16% developed erectile problems. Of the men who developed erectile dysfunction, 22% were in lowest tertile for serum testosterone levels, but 12% were in highest tertile. Other studies in healthy older men have shown that testosterone levels may correlate with sexual desire, but not with erectile function or coitus frequency.

Erectile dysfunction and lower urinary tract symptoms (LUTS), occurring as the result of benign prostatic hyperplasia (BPH), have significant effects on each other. Treatment of one can often improve the other. Both LUTS and erectile dysfunction are prevalent in the older male and frequently coassociate, contributing to diminished quality of life. Epidemiologic studies have shown strong associations between LUTS and erectile dysfunction, with a temporal relationship in onset and cessation and a dose response. A study in older men who had both erectile dysfunction and LUTS and were treated with the phosphodiesterase-5 (PDE-5) inhibitor, sildenafil, for 12 weeks, reported that both erectile function and LUTS symptoms improved with the sildenafil treatment.

While transurethral resection of the prostate (TURP) for BPH seldom results in erectile dysfunction, surgery for prostate cancer is more extensive and results in some degree of erectile dysfunction in about 60% of men. Nerve sparing surgery offers a greater chance of preserving sexual potency. In addition, penile rehabilitation with PDE-5 inhibitors immediately after surgery helps prevent complete erectile dysfunction. Peyronnie’s disease, in which fibrosis of the corpora occurs, also can lead to erectile problems.

A number of lifestyle factors have been associated with the development of erectile dysfunction. Obesity alone is associated with a 20% increased risk of developing erectile problems. Although men with obesity often have low serum total testosterone levels, their free testosterone levels usually are normal, making hypogonadism an unlikely cause for obesity-associated erectile dysfunction. Often, however, obese men have elevated serum estrogen levels owing to the conversion of androgens to estrogens in adipose tissue. Improving obesity can improve erectile function. Smoking also can cause erectile dysfunction, both from direct effects of nicotine on penile smooth muscle and from longer term effects on accelerating atherosclerosis. High levels of alcohol consumption are associated with erectile dysfunction, but moderate to low alcohol use has been associated with a lowering of the risk of erectile dysfunction. Physical activity alone, regardless of weight, can improve or delay development of erectile dysfunction.

A large number of medications have produced adverse drug events reports involving male sexual dysfunction, usually erectile dysfunction. These medications are listed in Table 49-4. By and large, the effects on sexual function are medication class effects based on mechanisms of action. It is unlikely that medications would precipitate symptomatic erectile dysfunction in a man who had absolutely no erectile problems prior to initiating the medication, but for men with mild preexisting erectile dysfunction, these medications may precipitate clinically significant erectile problems. Sometimes, when relying on adverse drug event reports in the absence of large randomized trials, conclusions regarding the potential of a medication to impact sexual function maybe exaggerated or incorrect. For example, although the 5-alpha reductase inhibitor, finasteride, has been reported to cause erectile dysfunction, analysis of the prospective quality of life data from the large Prostate Cancer Prevention Trial showed finasteride had no significant effect on sexual function.

A few comments about some of the medications listed in Table 49-4 are warranted. Among the diuretic antihypertensives, hydrochlorothiazide has frequently been reported to be associated with erectile problems, yet analysis of the large NHANES database for evaluation of the effect of medication exposure on erectile dysfunction using multivariate analysis showed that the use of thiazides was not associated with erectile dysfunction. Among the beta-blockers, propronolol is the one most associated with erectile dysfunction, and erectile problems are more often seen with the higher beta-blocker dosages. Among the antidepressants, both tricylic antidepressants and serotonin reuptake inhibitors are associated with erectile dysfunction. Mirtazapine, bupropion, and citalopram have been reported to cause somewhat fewer negative sexual side effects. Many benzodiazepines, including those used to counteract insomnia, are associated with exacerbation of erectile dysfunction, but sleep deprivation alone can induce sexual dysfunction.