Prevalence of Coronary Artery Disease Using Thallium-201 Single Photon Emission Computed Tomography among Patients Newly Undergoing Chronic Peritoneal Dialysis and Its Association with Mortality

Abstract

Background: Previous data about the prevalence of coronary artery disease in dialysis patients were mainly based on history or electrocardiogram. Methods: We evaluated the prevalence of coronary artery disease using routine thallium-201 single photon emission computed tomography (SPECT) in 227 patients at the start of chronic peritoneal dialysis between January 1996 and October 2003. We also analyzed its association with mortality. Results: Fifty-one patients (22.5%) were positive on thallium SPECT. There were significant differences in age, underlying diabetic nephropathy, and C-reactive protein (CRP), serum albumin, total cholesterol, and prealbumin levels among patients positive and negative on thallium SPECT. Multivariate logistic regression analysis showed that age (≧60 years), underlying diabetic nephropathy, and CRP (≧0.5 mg/dl) were independent predictors of positive thallium SPECT, with the patients positive for all three factors having a probability for positive thallium SPECT of 43%, whereas patients negative for all three factors had a probability of only 4%. Ninety patients died, and 137 survived during the median follow-up period of 34 (range 3–99) months. Kaplan-Meier survival analysis revealed that age, underlying diabetic nephropathy, serum albumin, prealbumin, and CRP levels, positive thallium SPECT, and smoking affected survival. Survival was not different according to gender, presence of hypertension, body mass index, total cholesterol, or lipoprotein(a). Cox regression analysis showed that only underlying diabetic nephropathy and age (≧60 years) were independent predictors of mortality. Conclusions: We found that 22.5% of the patients who started chronic peritoneal dialysis had a positive thallium SPECT. Age, underlying diabetic nephropathy, and CRP were independent predictors of a positive thallium SPECT. Underlying diabetic nephropathy and age, but not positive thallium SPECT, were independent predictors of mortality.