Testosterone and metabolic syndrome: The link

Metabolic syndrome (MetS) or "Syndrome X" which is a constellation of insulin resistance, hyperglycemia, hypertension, low high-density lipoprotein cholesterol (HDL-C), and increased very-low-density lipoprotein (VLDL) and triglyceride (TG) levels. It is one of the main threats for public health in the 21st century with its associated risk of cardiovascular disease. This condition affects a major chunk of mankind. International Diabetes Federation (IDF) estimated that around 20-25% of the adult population of the world has MetS. Several definitions have been put forward by different expert bodies leading to confusion. To overcome this, joint new statement of many expert group have been issued. Serum testosterone (T) has been shown to be associated with MetS. Several studies have shown a higher prevalence of MetS in subjects with low testosterone. There are also several studies showing a significant difference in serum T between those with MetS and those without. Serum T has also been shown to be associated with components of MetS and testosterone replacement therapy (TRT) improves various metabolic and anthropometric parameters in MetS. Patients with androgen deprivation for treatment of various cancers have also been reported to have higher prevalence of MetS. But the evidence of association is not sufficient evidence for the causation of MetS by low testosterone and long-term studies are needed to confirm whether T deficiency is the cause or is a feature of MetS.