Optimum Second Screening Point for Detection of Coronary Artery Disease in Hemodialysis Patients without Advanced Coronary Artery Disease

Abstract

Background: Screening for coronary artery disease (CAD) at the initiation of dialysis is a K/DOQI recommendation. However, it remains unclear when screening for CAD should be repeated in patients without significant disease at the time of starting dialysis. The objectives of this study were to determine: (1) the survival of hemodialysis (HD) patients without CAD at the initiation of dialysis, (2) the major predictors of CAD events, and (3) the best time to repeat screening for CAD after the initiation of HD. Methods: In order to assess the occurrence of de novo major adverse cardiac events (MACE) in HD patients without CAD, we prospectively followed patients who were normal according to screening tests for CAD performed at the initiation of HD. To detect CAD, 177 of 305 new HD patients underwent coronary angiography and/or pharmacologic stress thallium-201 single photon emission computed tomography within 1 month after starting HD. Among these 177 patients, 100 did not have significant CAD and they were followed for a median of 24 months. Results: Five MACE occurred during follow-up, but no events were observed within 1 year after starting HD. All 5 events occurred during the second year of HD (two events occurred immediately after the end of the first year). An increased level of C-reactive protein (CRP) was the only independent predictor of MACE (hazard ratio: 1.39; 95% CI: 1.03–1.78, p = 0.008) according to Cox regression analysis. The optimum cut-off value of CRP for predicting MACE was 3.5 mg/l. The MACE-free rate at 2 years (99 vs. 79%, p = 0.0008) was significantly higher in patients with a CRP level (3.5 mg/l than in those with a level <3.5 mg/l). Conclusion: One year after the initiation of HD could be the optimum time to repeat screening for CAD in patients without disease at the initiation of HD. If the serum CRP level is less than 3.5 mg/l, postponing repeat screening for CAD could be considered.