BACKGROUND:Higher androgen and lower estrogen levels are associated with cardiovascular disease (CVD) risk factors in women. However, studies on sex hormones and incident CVD events in women have yielded conflicting results. OBJECTIVES:The authors assessed the associations of sex hormone levels with incident CVD, coronary heart disease (CHD), and heart failure (HF) events among women without CVD at baseline. METHODS:The authors studied 2,834 post-menopausal women participating in the MESA (Multi-Ethnic Study of Atherosclerosis) with testosterone, estradiol, dehydroepiandrosterone, and sex hormone binding globulin (SHBG) levels measured at baseline (2000 to 2002). They used Cox hazard models to evaluate associations of sex hormones with each outcome, adjusting for demographics, CVD risk factors, and hormone therapy use. RESULTS:The mean age was 64.9 ± 8.9 years. During 12.1 years of follow-up, 283 CVD, 171 CHD, and 103 HF incident events occurred. In multivariable-adjusted models, the hazard ratio (95% confidence interval [CI]) associated with 1 SD greater log-transformed sex hormone level for the respective outcomes of CVD, CHD, and HF were as follows: total testosterone: 1.14 (95% CI: 1.01 to 1.29), 1.20 (95% CI: 1.03 to 1.40), 1.09 (95% CI: 0.90 to 1.34); estradiol: 0.94 (95% CI: 0.80 to 1.11), 0.77 (95% CI: 0.63 to 0.95), 0.78 (95% CI: 0.60 to 1.02); and testosterone/estradiol ratio: 1.19 (95% CI: 1.02 to 1.40), 1.45 (95% CI: 1.19 to 1.78), 1.31 (95% CI: 1.01 to 1.70). Dehydroepiandrosterone and SHBG levels were not associated with these outcomes. CONCLUSIONS:Among post-menopausal women, a higher testosterone/estradiol ratio was associated with an elevated risk for incident CVD, CHD, and HF events, higher levels of testosterone associated with increased CVD and CHD, whereas higher estradiol levels were associated with a lower CHD risk. Sex hormone levels after menopause are associated with women's increased CVD risk later in life.