Sex steroids and mortality in men referred for coronary angiography

OBJECTIVE: Accumulating evidence suggests that sex steroids are associated with various chronic diseases. We aimed at evaluating whether total testosterone (TT), free testosterone (FT) and sex hormone-binding globulin (SHBG) are associated with all-cause mortality and specific fatal events. DESIGN, SETTING AND PARTICIPANTS: We measured TT and SHBG levels in 2078 men who were routinely referred for coronary angiography (1997-2000). FT was calculated according to Vermeulen. MEASUREMENTS: The main outcome measures were Cox proportional hazard ratios (HRs) for mortality from all causes, from cardiovascular and non-cardiovascular causes and from cancer according to SHBG, FT and TT. RESULTS: Multivariable-adjusted HRs (with 95% confidence intervals) in the fourth compared to the first SHBG quartile for all-cause, non-cardiovascular and cancer mortality were 1·61 (1·16-2·23), 2·44 (1·39-4·28), and 2·86 (1·03-7·32), respectively. There was no significant association of SHBG levels with cardiovascular mortality. All-cause mortality was significantly reduced per 1 SD increase in FT in the multivariate-adjusted analyses [0·49 (0·30-0·81)]. We observed no significant associations of FT with cardiovascular and cancer mortality, and TT levels were not independently related to any fatal events. CONCLUSION: High levels of SHBG are associated with adverse health outcomes in a large cohort of older men referred for coronary angiography. Further studies are warranted to confirm our results and to elucidate the underlying mechanisms for our findings.