Epidemiological studies show a high prevalence of hypogonadism in men with obesity, type 2 diabetes and other components of the metabolic syndrome. Restoring physiological concentrations of testosterone in hypogonadal men by long-term testosterone therapy of 5 years and longer has resulted in substantial weight loss and meaningful improvement of glycaemic control. Blood pressure was reduced and lipid pattern improved. The longer the observation time in real-life studies, the more robust the results.
Both magnitude and sustainability of treatment effects, predominantly based on observational studies with and without untreated control groups and a duration of up to 8 years, are of such interest that further studies with an adequate design should be performed. However, conducting placebo-controlled trials over several years in men diagnosed with hypogonadism may not be considered ethical.
A host of studies have shown that adequate testosterone therapy reduces major adverse cardiovascular events and mortality in hypogonadal men. These studies are consistent with the observed beneficial effects of long-term testosterone treatment on the classical cardiovascular risk factors (visceral obesity, hypertension, dyslipidaemia, insulin resistance). In addition, testosterone has anti-inflammatory and anti-coagulatory properties.
According to what is known today, there is sufficient evidence to recommend measuring testosterone in men with obesity and/or type 2 diabetes. If hypogonadism is diagnosed, testosterone therapy should be considered. Adequate therapy, i.e. restoring testosterone levels to the mid- to high normal range for life seems the most promising approach. Medication adherence, as in all chronic diseases, is essential.
Biographical details: Prof. h.c.* Dr Farid Saad is manager of Global Medical Affairs Andrology of Bayer Pharma AG. 1953 born in Alexandria, Egypt; 1973 1980 studies of human and veterinary medicine; 1990 1998 specialist for reproductive endocrinology, pediatric endocrinology, and andrology, Ferring GmbH, Kiel, Germany; 1998 2001 leader of clinical development andrology, Jenapharm, Jena, Germany; specialist in endocrinology of aging, male aging, male hormonal fertility control; 2001 2007 leader of product group Male Health Care, Schering AG, Berlin, Germany; since March 2007 Global Medical Affairs Andrology, Bayer Pharma AG. He has authored and co-authored more than 120 peer-reviewed papers and more than 600 scientific abstracts. In 2005 he received a honorary professorship in clinical research and endocrinology at Gulf Medical University, Ajman, United Arab Emirates and in 2006 a honorary professorship at Mens Health Reproduction Study Center, Hang Tuah University, Surabaya, Indonesia. *Gulf Medical University School of Medicine, Ajman, United Arab Emirates.