Testosterone and sex hormone-binding globulin in dysglycemic women at high cardiovascular risk: A report from the Outcome Reduction with an Initial Glargine Intervention trial

Abstract

Aims: Total and free testosterone and sex hormone-binding globulin may affect cardiovascular prognosis in women. The objective was to study the association between sex hormones and prognosis in women with dysglycemia and high cardiovascular risk. Methods: This epidemiological report included dysglycemic women from the Outcome Reduction with an Initial Glargine Intervention trial ( n = 2848) with baseline total testosterone and sex hormone-binding globulin. Free testosterone was calculated with the Vermeulen formula. Cox regression analyses adjusted for variables including age, previous diseases and pharmacological treatments were used to estimate the association between these levels and the composite cardiovascular outcome (death from cardiovascular causes, nonfatal myocardial infarction or nonfatal stroke) and all-cause mortality per one standard deviation. Results: Patients (73% post-menopausal) were followed for a median of 6.1 years during which 377 cardiovascular events and 389 deaths occurred. In Cox analyses, total and free testosterone were not associated with any outcomes, but sex hormone-binding globulin was related to all-cause mortality in age adjusted (HR 1.15; 95% CI 1.06–1.24; p < 0.01) and fully adjusted analyses (HR 1.14; 95% CI 1.05–1.24; p < 0.01). Conclusions: Increasing levels of baseline sex hormone-binding globulin were associated with an increased risk of all-cause mortality in dysglycemic women at high cardiovascular risk. Trial registration ClinicalTrials.gov no. NCT00069784.