High triglycerides (TG) and low high-density lipoprotein cholesterol (HDL-C) are important cardiovascular risk factors in women. The prognostic utility of the TG/HDL-C ratio, a marker for insulin resistance and small dense low-density lipoprotein particles, is unknown among high-risk women. Methods: We studied 544 women without prior myocardial infarction or coronary revascularization, referred for clinically indicated coronary angiography and enrolled in the Women's Ischemia Syndrome Evaluation (WISE). Fasting lipid profiles and detailed demographic and clinical data were obtained at baseline. Multivariate Cox-proportional hazards models for all-cause mortality and cardiovascular events (death, myocardial infarction, heart failure, stroke) over a median follow-up of 6 years were constructed using log TG/HDL-C ratio as a predictor variable and accounting for traditional cardiovascular risk factors. Results: Mean age was 57 ± 11 years; 84% were white, 55% hypertensive, 20% diabetic, 50% current or prior smokers. Triglyceride/HDL-C ranged from 0.3 to 18.4 (median 2.2, first quartile 0.35 to <1.4, fourth quartile 3.66-18.4). Deaths (n = 33) and cardiovascular events (n = 83) increased across TG/HDL-C quartiles (both P < .05 for trend). Triglyceride/HDL-C was a strong independent predictor of mortality in models adjusted for age, race, smoking, hypertension, diabetes, and angiographic coronary disease severity (hazard ratio 1.95, 95% CI 1.05-3.64, P = .04). For cardiovascular events, the multivariate hazard ratio was 1.54 (95% CI 1.05-2.22, P = .03) when adjusted for demographic and clinical variables, but became nonsignificant when angiographic results were included. Conclusion: Among women with suspected ischemia, the TG/HDL-C ratio is a powerful independent predictor of all-cause mortality and cardiovascular events. © 2009 Mosby, Inc.