Androgen replacement therapy in late-onset hypogonadism: current concepts and controversies - a mini-review.

BACKGROUND Normal testicular function is essential for the maintenance of male physical strength and behaviour irrespective of age. A new term of late-onset hypogonadism (LOH) has been coined for the condition of decreased testosterone (T) and hypogonadal symptoms in ageing men. OBJECTIVE The most important testicular hormone, T, is responsible for the gender-specific androgenic-anabolic effects in men. Testicular T production remains stable until around the age of 40 years after which it declines by 1-2% annually. Despite this age-related decline, serum T levels in most older men remain within the reference range of younger men. The decreasing androgen levels are paralleled by well-defined objective biological and nonspecific subjective signs and symptoms of ageing. Because these symptoms are similar to those observed in young men with documented hypogonadism, androgen replacement therapy (ART) has been considered a logical way to treat them. METHODS A thorough review of the existing literature was performed to evaluate the current concepts and controversies related to ageing men and ART. RESULTS Although it is intuitively logical that the symptoms of LOH are due to the ageing-related deficiency of T, and that they can be reversed by ART, the evidence for this is still variable and often weak. In particular, evidence-based information about long-term benefits and risks of ART in ageing men is largely missing. CONCLUSIONS Despite widespread use, evidence-based proof for the objective benefits and side effects of ART of elderly men is still scanty, and such treatments should be considered experimental.