Review: Testosterone and the metabolic syndrome

Abstract

Metabolic syndrome and testosterone deficiency in men are closely linked. Epidemiological studies have shown that low testosterone levels are associated with obesity, insulin resistance and an adverse lipid profile in men. Conversely in men with metabolic syndrome and type 2 diabetes have a high prevalence of hypogonadism. Metabolic syndrome and low testosterone status are both independently associated with increased all-cause and cardiovascular mortality. Observational and experimental data suggest that physiological replacement of testosterone produces improvement in insulin resistance, obesity, dyslipidaemia and sexual dysfunction along with improved quality of life. However, there are no long-term interventional studies to assess the effect of testosterone replacement on mortality in men with low testosterone levels. This article reviews the observational and interventional clinical data in relation to testosterone and metabolic syndrome.