Does Male Menopause Actually Exist?

Male-menopauseNo one really knows if male menopause exists. Menopause in women is characterized by a permanent and precipitous drop in the production of estrogen over a period of a few years. This life-changing event marks the end of fertility and can be accompanied by a constellation of symptoms including hot flashes, mood changes, and other physiological and cognitive disturbances. Men, for their part, suffer a very gradual decline in testosterone over several decades. After age 40, an otherwise healthy male's testosterone levels decrease, on average, between just 0.5 and 1 percent each year. A number of common conditions, like obesity, may hasten this decline.

That doesn't sound like the kind of abrupt shift women go through, but men have mourned their sagging vigor and vitality for decades (at least). During the 1920s, thousands of men seeking an endocrine boost underwent testicular transplantation, in which doctors grafted the sex glands of monkeys or goats onto their patients' testicles. Beginning in the late 1930s, medical and popular literature debated the existence of a male climacteric, a disruptive midlife hormonal change akin to the end of menstruation. The phrase "male menopause" first appeared in print in 1950. Although serious medical discussion about it went out of fashion by mid-decade, researchers revived the idea in the late 1980s under the name andropause. More recent journal articles use the terms late-onset hypogonadism or partial androgen deficiency in aging men (PADAM) to refer to a syndrome of low serum testosterone levels and the presence of certain symptoms. 

Medical historian Elizabeth Watkins of the University of California-San Francisco believes the resurgence of the concept of male menopause can be traced to a societal shift toward a desire for biological explanations and to the popularity of hormone replacement therapy in women. But if male menopause is a term that could apply to some men, it's not universal. Only one quarter of middle-aged and older men suffer from low testosterone, typically defined as a total blood concentration of less than 300 nanograms per deciliter, though measured hormone levels vary widely due to circadian rhythm and inconsistency among laboratories.

As epidemiologist Andre Araujo of the New England Research Institute found, the proportion of American men suffering from symptomatic testosterone deficiency—low levels plus demonstrable physical, cognitive, or sexual dysfunction—is even lower, roughly 6 percent. A more recent European study using slightly different diagnostic criteria found an average prevalence of this ailment of just 2.1 percent.

Nevertheless, the treatment battle wages: Between 1992 and 2004, annual U.S. prescriptions for testosterone treatment, typically in gel or patch form, rose nearly 20-fold from 122,000 to 2.4 million. In its 2010 clinical practice guidelines, the Endocrine Society discourages a general policy of prescribing therapeutic testosterone to older men with low testosterone levels. Such treatment may increase men's risk of developing prostate cancer and heart disease, and can result in baldness, fluid retention, and a dangerous excess of red blood cells. Even if Mad Max does number among that 2 percent, he can't blame low testosterone for his violent outbursts.

While experts agree that adult men experience a slow decline in hormone production over their lifetimes, and that a small subset also suffers troubling physiological changes, increased aggression isn't one of them. In fact, researchers have yet to even establish a firm causal link between late-onset low testosterone in middle-aged and elderly men and the symptoms traditionally associated with androgen deficiency, which include sexual difficulties such as low desire, erectile dysfunction, and decreased frequency of morning erection, physical symptoms such as loss of muscle mass, strength, and bone density, as well as sleep disturbance, depressed mood, irritability, fatigue, and poor concentration.

Many of these symptoms overlap with the natural effects of aging and can be caused by a host of other medical conditions. A new NIH-supported trial led by Dr. Peter J. Snyder at the University of Pennsylvania aims to tease out some of these causal connections by studying the effects of hormone replacement therapy in older men. At the moment, though, it doesn't look like age-related hormonal decline can explain abusive behavior, much less excuse it. Perhaps next time Mel Gibson can blame his raving anti-Semitism on a yeast infection