genitourinary disorders
Male Reproductive Endocrinology
Effects of Aging
Both hypothalamic secretion of gonadotropin-releasing hormone (GnRH) and the response of Leydig cells to follicle-stimulating hormone (FSH) and luteinizing hormone (LH) diminish with aging. In older people, Leydig cells decrease in number as well. Beginning at about age 30, a man’s serum totaltestosteronelevels decline by 1 to 2% annually. Men aged 70 to 80 tend to have serumtestosteronelevels that are about one half to two thirds of those of men in their 20s. In addition, sex hormone–binding globulin (SHBG) levels increase with aging, causing an even greater decline in serum free and bioavailabletestosterone. FSH and LH levels tend to be normal or high-normal. These age-related changes are referred to as the andropause, although there are no abrupt changes in hormone levels (and corresponding symptoms) as occur in menopause. The decline intestosteronemay contribute to a combination of symptoms that has been termedandrogen deficiency of the aging male(ADAM), which includes Age-related muscle loss Increased fat deposition Osteopenia Libido and Cognitive decline , they are diagnosed with Male Hypogonadism and are eligible for treatment with supplemental Testosteronesupplementation in men with low-normal levels oftestosteroneis controversial. Some experts recommend a trial oftestosteronesupplementation in older men with symptoms or signs of hypogonadism and whose serumtestosteronelevels are slightly below the lower limit of normal. No data favor any of thetestosteronepreparations specifically for use in ADAM, although daily transcutaneous applications appear to be the most physiologic and best tolerated. 