Endocrine Abstracts

The search for eternal youth has created a market for treatments that might affect the process of aging, and testosterone (T) is one of the hormones that have been in focus. It is well accepted that T levels decline with increasing age, although the individual variation is large. Male hypogonadism is characterised by a low serum T level in combination with a diversity of symptoms and signs such as reduced libido and vitality, decreased muscle mass, increased fat mass and depression. Similar symptoms in combination with subnormal T levels are seen in some elderly men, and several attempts have been made to identify symptoms and corresponding T levels that would define late-onset hypogonadism as a syndrome. However, symptoms of T deficiency in elderly men are nonspecific and are difficult to discriminate from symptoms of other conditions and diseases common in older men. Despite this uncertainty, the sale of T has increased tremendously over the last few years.

In observational studies low T levels tends to predict the development of metabolic syndrome and type 2 diabetes, and have been associated with all-cause mortality and cardiovascular disease mortality. Results from small intervention studies, however, are diverging but have mainly shown that T treatment in older men increase fat-free mass and decrease overall body fat while the effect on glucose and lipid metabolism have been slight. Weight reduction, on the other hand, in obese men with low T levels has been shown to normalize T levels as well as significantly improve both lipid and glucose levels. Thus, low T levels may be seen as a marker of general health, and the primary treatment should probably be lifestyle changes. T treatment should not routinely be initiated in elderly men with subnormal T levels until benefits and safety are confirmed in well performed studies.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.