The fall in testosterone levels with age appears to be a real phenomenon. Declining testicular function and hypothalamic dysregulation appear to be the mechanisms explaining the fall in testosterone levels with age. The increased prevalence of obesity and chronic illness in ageing men both cause a large drop in testosterone levels independent of ageing. Age-related hypogonadism appears to be different to other 'classical' causes of hypogonadism. Testosterone levels are not unequivocally low and associated symptoms are non-specific. In frail older men with low testosterone levels, testosterone therapy appears to improve QOL and physical function. In less frail men, however, effects of testosterone therapy in the ageing male are small and/or inconsistent. There remains an urgent need for randomised clinical trials with sufficient size, duration and power to determine specific benefits and risks of testosterone therapy in older men.
A total of 209 men (mean age, 74 years) were enrolled at the time the trial was terminated. At baseline, there was a high prevalence of hypertension, diabetes, hyperlipidemia, and obesity among the participants. During the course of the study, the testosterone group had higher rates of cardiac, respiratory, and dermatologic events than did the placebo group. A total of 23 subjects in the testosterone group, as compared with 5 in the placebo group, had cardiovascular-related adverse events. The relative risk of a cardiovascular-related adverse event remained constant throughout the 6-month treatment period. As compared with the placebo group, the testosterone group had significantly greater improvements in leg-press and chest-press strength and in stair climbing while carrying a load.