Abstract 13274: Mild Renal Insufficiency is an Independent Predictor of Coronary Microvascular Dysfunction among Women With Symptoms/Signs of Ischemia: A report From the Women’s Ischemia Syndrome Evaluation (WISE)
Introduction: Chronic kidney disease (CKD) is associated with accelerated atherosclerosis and decreased survival. We have previously shown that, among women with symptoms and signs of ischemia enrolled in the WISE, mild renal insufficiency was associated with increased mortality that is not completely explained by the severity of underlying obstructive coronary artery disease (CAD). Other WISE data indicate that in such women, coronary microvascular dysfunction (reduced coronary flow reserve, CFR) is the best predictor of adverse outcomes. CKD is also associated with microvascular dysfunction in other organ systems. Accordingly, we hypothesized that mild renal insufficiency is a predictor of coronary microvascular dysfunction.
Methods: We studied 198 women undergoing coronary angiography for suspected ischemia who had measurements of CFR and renal function. Glomerular filtration rate was estimated (eGFR) from the Cockroft Gault formula, excluding those with hyperfiltration (eGFR>140). We used Pearson correlation to test the univariate association between eGFR and log CFR. Multivariable linear regression analysis was performed to adjust for baseline covariates.
Results: The majority were Caucasian (82%) and post-menopausal (78%) with multiple CAD risk factors: Family history of CAD in 67%, hypertension 55%, dyslipidemia 53%, metabolic syndrome 44%, diabetes 20%, and current smoking 20%. However, less than a quarter (24%) had obstructive CAD (>50% stenosis). The median eGFR was 94 (IQR 75,112). In univariate analysis, eGFR was correlated with CFR r=0.23 (p=0.003). Multivariable modeling demonstrated eGFR as an independent predictor of CFR that persisted after adjustment for diabetes, dyslipidemia and functional status. Other CAD risk factors, including CAD, did not enter the model in stepwise regression. Each 10-unit decrease in eGFR was associated with a 0.04-unit decrease in CFR (p<0.005).
Conclusions: Mild renal insufficiency is significantly associated with reduced CFR in women with symptoms and signs of ischemia. Coronary microvascular dysfunction deserves additional study as a contributor to the increased cardiovascular morbidity/mortality documented in CKD patients.
- © 2013 by American Heart Association, Inc.