Low free testosterone levels are associated with all-cause and cardiovascular mortality in postmenopausal diabetic women.

Abstract

Hyperandrogenemia is associated with cardiovascular risk factors in women but evidence about the relationship of testosterone levels with mortality is sparse. We aimed to evaluate whether total testosterone (TT), free testosterone (FT), and sex hormone-binding globulin (SHBG) are associated with all-cause and cardiovascular mortality in a cohort of postmenopausal women. We measured TT and SHBG levels in 875 postmenopausal women who were referred for coronary angiography (during 1997-2000). FT was calculated according to the Vermeulen method. The main outcome measures were Cox proportional hazard ratios (HRs) for mortality from all causes and from cardiovascular causes. After a median follow-up time of 7.7 years, 179 women (20.5%) had died. There were 101 deaths due to cardiovascular disease (56.4% of all deaths). We found no association of FT, TT, and SHBG levels with mortality in all postmenopausal women. In postmenopausal diabetic women, multivariable-adjusted HRs (with 95% CIs) in the fourth compared with the first FT quartile for all-cause and cardiovascular mortality were 0.38 (0.08-0.90), P = 0.025, and 0.28 (0.08-0.90), P = 0.032, respectively. We found no association of TT and SHBG with mortality in diabetic postmenopausal women. In postmenopausal diabetic women referred for coronary angiography, low FT levels are independently associated with increased all-cause and cardiovascular mortality.