Obesity, leptins, hypogonadism and waist-hip ratio in men: An interplay

Abstract

Adipose tissue and androgens have a reciprocal link in obese men. Hypogonadism is a nonspecific term for decreased testicular function. It is diagnosed by the low serum testosterone levels and low serum gonadotropin levels due to various etiologies. A deficiency of Testosterone is associated with decreased libido, male erectile dysfunction, excessive sweating and symptoms associated with aging like lack of energy, fatigue, central adiposity, reduced strength, cognitive decline and depression (Davidson et al. 1983; Yesavage et al. 1985). Many of the symptoms are seen in men with increasing age and are not specific in all cases of hypogonadism. Obesity predicts increased mortality due to the link with co morbidities such as diabetes mellitus, cardiovascular disease, the Metabolic Syndrome and Obstructive sleep apnoea (Poirier et al. 2006). Anthropometric measurements like Body Mass Index (BMI), Waist Hip Ratio (WHR) and Waist Circumference (WC) and Waist to Height Ratio (WHtR) have been used as tools to assess obesity and hence the cardiovascular risk status in individuals with hypogonadism. The Waist Hip Ratio (WHR) measurement is considered a good indicator of abdominal obesity which predisposes to serious health risks. The WHO recommends these measurements as a universal criterion for the detection of obesity. WHR which is a better measure of abdominal fat accumulation has been implicated as a more sensitive predictor of cardiovascular risk than BMI (Cambien et al. 1980; Yusuf et al. 2005). There is a fundamental relationship between energy balance and reproductive function in the mammalian species wherein population growth is controlled during times of scarcity. Recent epidemiological studies have shown that Androgens play an important role in the pathogenesis of Metabolic Syndrome in men. Conversely hypogonadism can develop in established metabolic syndrome (Laaksonen et al. 2005). Studies have shown that Androgen therapy has been found to reduce visceral abdominal obesity which is the main target in the treatment of obesity in hypogonadal men (Schroeder et al. 2004). The WHR is not recommended to be used as a lone indicator of cardiovascular disease in an obese individual as it was thought earlier. Recent studies have shown Waist Circumference to be a better tool to assess the cardiovascular risk than WHR.