Renal insufficiency and cardiovascular events in postmenopausal women with coronary heart disease

OBJECTIVES This study sought to determine the independent association of renal insufficiency with cardiovascular risk among women with known coronary heart disease (CHD). BACKGROUND Although patients with end-stage renal disease and proteinuria are at high risk for cardiovascular events, little is known about the cardiovascular risk associated with moderate renal insufficiency. METHODS The Heart and Estrogen/progestin Replacement Study (HERS) was a clinical trial among 2,763 women with coronary disease who were randomized to conjugated estrogen plus progestins or identical placebo and followed for a mean of 4.1 years. Women were categorized as having normal renal function (creatinine < 1.2 mg/dl; N = 2,012), mild renal insufficiency (1.2 mg/dl to 1.4 mg/dl; N = 567) and moderate renal insufficiency (>1.4 mg/dl; N = 182). We examined the independent association of renal function with incident cardiovascular events including CHD death, nonfatal myocardial infarction, hospitalization for unstable angina, stroke and transient ischemic attacks. RESULTS Compared with women with normal renal function, those with mild and moderate renal insufficiency were older, more likely to be black, have a history of hypertension and diabetes and have higher serum levels of triglycerides and lipoprotein(a). After multivariate adjustment, both mild (relative hazards [RH] = 1.24; 95% confidence interval [CI]: 1.0 to 1.5) and moderate renal insufficiency (RH = 1.57; 95% CI: 1.2 to 2.1) were independently associated with increased risk for cardiovascular events compared with women with normal renal function. CONCLUSIONS Renal insufficiency is an independent risk factor for cardiovascular events in postmenopausal women with known coronary artery disease. Renal function may add helpful information to CHD risk stratification.