Low serum testosterone is associated with increased adiposity, an adverse metabolic risk profile, and atherosclerosis while polymorphisms in the sex hormone–binding globulin (SHBG) gene are associated with the risk of type 2 diabetes. However, few studies have addressed whether endogenous testosterone or SHBG are predictors of cardiovascular (CV) events. In this prospective population-based Swedish study (2416 men; aged 69 to 81 years), gas chromatography/mass spectrometry was used to analyze baseline levels of testosterone and SHBG was measured by immunoradiometric assay. During a median five-year follow-up, 485 CV events occurred. Both total testosterone and SHBG levels were inversely associated with the risk of CV events (p = 0.009 and p = 0.012, respectively). Men in the highest quartile of testosterone (≥550 ng/dl) had a lower risk of CV events compared with men in the three lower quartiles (hazard ratio: 0.70; 95% CI: 0.56-0.88). This association remained after adjustment for traditional CV risk factors and was not changed in the analyses excluding men with known CV disease at baseline. The authors concluded that high serum testosterone predicted a reduced five-year risk of CV events in elderly men. J Am Coll Cardiol. 2011 Oct 11;58(16):1674-81. PMID: 21982312.
