Low Testosterone in Older Men Less Common Than Thought
Study does find some association between nine symptoms and 'male menopause'
By Amanda GardnerHealthDay Reporter
Study does find some association between nine symptoms and 'male menopause.'
WEDNESDAY, June 16 (HealthDay News) -- In describing a set of concrete symptoms for "male menopause" for the first time, British researchers have also determined that only about 2 percent of men aged 40 to 80 suffer from the condition, far less than previously thought.
Male menopause, also called "andropause" or late-onset hypogonadism, supposedly results from declines in testosterone production that occur later in life, but there has been some debate on how real the phenomenon is, the study authors noted.
"Some aging men indeed suffer from [male menopause]. It is a genuine syndrome, but much less common than previously assumed," concluded Dr. Ilpo Huhtaniemi, senior author of a study published online June 16 in the New England Journal of Medicine.
"This is important because it demonstrates that genuine symptomatic androgen deficiencies [androgens are male hormones] is less common than believed, and that only the right patients [should] get androgen treatment," added Huhtaniemi, a professor of reproductive endocrinology in the department of surgery and cancer at Imperial College London.
Many men have been taking testosterone supplements to combat the perceived effects of aging, even though it's not clear if taking these supplements help or if they're even safe. The result has been mass confusion, not only as to whether male menopause exists but also how to treat it.
"A lot of people abuse testosterone who shouldn't and a lot of men who should get it aren't," said Dr. Michael Hermans, an associate professor of surgery in the Texas A&M Health Science Center College of Medicine and chief of the section of andrology, male sexual dysfunction and male infertility at Scott & White in Temple, Texas.
For this study, the research team, from Imperial College London and the University of Manchester, measured testosterone levels in 3,369 men aged 40 to 79 and then correlated these levels with different symptoms.
Of 32 possible symptoms, only nine were linked with decreased testosterone levels. Three were physical -- not being able to engage in strenuous physical activity, not being able to walk more than 1 kilometer and not being able to bend over or kneel -- and three were psychological -- low energy, sadness and fatigue.
But these six symptoms were only peripherally linked to low testosterone levels.
Three sexual symptoms -- less frequent morning erections, lower sex drive and erectile dysfunction -- were more robustly related to testosterone levels.
Men need to have all three sexual symptoms plus measurably lower levels of testosterone to qualify for the diagnosis of late-onset hypogonadism, the authors stated.
But even with this new diagnostic criteria, the challenge of treating men with sexual and other symptoms of male menopause is still far from straightforward.
"These symptoms that are associated with hypogonadism are not necessarily going to be treated by testosterone therapy," pointed out Dr. Natan Bar-Chama, director of male reproductive medicine and an associate professor of urology at Mount Sinai Medical Center in New York City. "We know very well that erectile dysfunction is complicated. It's associated with other co-morbidities and the ability to regain normal erectile function is often not successfully treated with just testosterone."
"Just because an older guy comes in and says he has a bad sex life, you don't automatically give him testosterone," Hermans added.
And even though there are any number of testosterone products available -- from patches to pellets -- there isn't much research on how much they really help men, Hermans said, or whether they are safe.
The U.S. National Library of Medicine has more about hypogonadism.
SOURCES: Ilpo Huhtaniemi, M.D., Ph.D., professor, reproductive endocrinology, department of surgery and cancer, Imperial College London; Natan Bar-Chama, M.D., director, male reproductive medicine, and associate professor, urology, Mount Sinai Medical Center, New York City; Michael Hermans, M.D., associate professor, surgery, Texas A&M Health Science Center College of Medicine, and chief, section of andrology, male sexual dysfunction and male infertility, Scott & White, Temple, Texas; June 16, 2010, New England Journal of Medicine, online
Copyright @2010 HealthDay. All Rights Reserved.
Published at www.nejm.org June 16, 2010 (10.1056/NEJMoa0911101)
Identification of Late-Onset Hypogonadism in Middle-Aged and Elderly Men
Frederick C.W. Wu, M.D., Abdelouahid Tajar, Ph.D., Jennifer M. Beynon, M.B., Stephen R. Pye, M.Phil., Alan J. Silman, M.D., Joseph D. Finn, B.Sc., Terence W. O'Neill, M.D., Gyorgy Bartfai, M.D., Felipe F. Casanueva, M.D., Ph.D., Gianni Forti, M.D., Aleksander Giwercman, M.D., Ph.D., Thang S. Han, M.D., Ph.D., Krzysztof Kula, M.D., Ph.D., Michael E.J. Lean, M.D., Neil Pendleton, M.D., Margus Punab, M.D., Ph.D., Steven Boonen, M.D., Ph.D., Dirk Vanderschueren, M.D., Ph.D., Fernand Labrie, M.D., Ph.D., Ilpo T. Huhtaniemi, M.D., Ph.D., for the EMAS Group
Background The association between aging-related testosterone deficiency and late-onset hypogonadism in men remains a controversial concept. We sought evidence-based criteria for identifying late-onset hypogonadism in the general population on the basis of an association between symptoms and a low testosterone level.
Methods We surveyed a random population sample of 3369 men between the ages of 40 and 79 years at eight European centers. Using questionnaires, we collected data with regard to the subjects' general, sexual, physical, and psychological health. Levels of total testosterone were measured in morning blood samples by mass spectrometry, and free testosterone levels were calculated with the use of Vermeulen's formula. Data were randomly split into separate training and validation sets for confirmatory analyses.
Results In the training set, symptoms of poor morning erection, low sexual desire, erectile dysfunction, inability to perform vigorous activity, depression, and fatigue were significantly related to the testosterone level. Increased probabilities of the three sexual symptoms and limited physical vigor were discernible with decreased testosterone levels (ranges, 8.0 to 13.0 nmol per liter [2.3 to 3.7 ng per milliliter] for total testosterone and 160 to 280 pmol per liter [46 to 81 pg per milliliter] for free testosterone). However, only the three sexual symptoms had a syndromic association with decreased testosterone levels. An inverse relationship between an increasing number of sexual symptoms and a decreasing testosterone level was observed. These relationships were independently confirmed in the validation set, in which the strengths of the association between symptoms and low testosterone levels determined the minimum criteria necessary to identify late-onset hypogonadism.
Conclusions Late-onset hypogonadism can be defined by the presence of at least three sexual symptoms associated with a total testosterone level of less than 11 nmol per liter (3.2 ng per milliliter) and a free testosterone level of less than 220 pmol per liter (64 pg per milliliter).
The clinical importance of an age-related reduction in the testosterone level1,2,3 remains controversial.4,5 Because of the uncertainty regarding the nature of testosterone deficiency in aging men,6,7,8,9 recent guidelines have suggested that so-called late-onset hypogonadism be regarded as a clinical and biochemical state with advancing age, characterized by particular symptoms and a low level of serum testosterone.10,11 However, few data on hypogonadism in aging men are available4,8,12 because of the lack of evidence regarding the exact criteria for identifying testosterone deficiency in older men who do not have pathological hypogonadism.6,13 Although a familiar array of symptoms typify severe testosterone deficiency (total testosterone level, <6 to 8 nmol per liter [1.7 to 2.3 ng per milliliter]) in younger patients, symptoms in aging men are nonspecific and are mimicked by other prevalent disorders. The testosterone level below which symptoms of androgen deficiency emerge and adverse health outcomes ensue in older men remains unclear, and the use of arbitrary thresholds is not appropriate.11
We conducted a study in a general population of middle-aged and elderly men in order to characterize the clinical symptoms associated with a low testosterone level, to identify the thresholds of testosterone below which such symptoms become increasingly prevalent, and to define essential criteria for the syndrome of late-onset hypogonadism on the basis of the presence of symptoms associated with a low testosterone level.14
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