Effect of statins and white blood cell count on mortality in patients with ischemic left ventricular dysfunction undergoing percutaneous coronary intervention

摘要

Background: While morbidity and mortality were shown to be increased in the setting of an elevated white blood cell (WBC) count for patients with acute coronary syndrome, the impact of statin therapy on mortality for patients with an elevated WBC count is unknown in high‐risk patients with coronary artery disease. Hypothesis: The goal of this study was to determine whether statin therapy improved survival in patients with elevated WBC count undergoing percutaneous coronary intervention (PCI) with preexisting left ventricular (LV) dysfunction, a population at high risk for adverse outcomes. Methods: We retrospectively evaluated consecutive patient procedures performed at our institution from 1996 through 1999. Patients had a technically adequate angiographic left ventriculogram with a calculated ejection fraction(EF) ≤ 50%. Patients with prior coronary artery bypass graft were excluded. Mortality data were retrieved using the U.S. Social Security Death Index. Follow‐up ranged from 3.5 to 6.5 years. Means are provided with ± standard deviation, and p values <0.05 were considered significant. Results: Of the study population of 238 patients (average EF 39 ± 9.8%, mean age 57.5 ± 12 years, 68% men) 61%un‐derwent PCI for a recent myocardial infarction, 68% received stents, and 65% were discharged on statins. Mean WBC count was 9,000 ± 3,100 cells/mm3, with 28% of patients having a WBC ≥ 10,000 cells/mm³. During follow‐up, 27% of our population died. Patients with a WBC ≥ 10,000 had worse survival than patients with WBC < 10,000 (1‐year survival: 86 vs. 96%, p<0.05; 3‐year survival: 79 vs. 89%, p<0.05). Survival was significantly improved in patients on statin therapy regardless of WBC count, but the greatest benefit tended to be in patients with WBC ≥ 10,000 (WBC ≥ 10,000; odds ratio [OR] 5.14, 95% confidence interval [CI] 1.44–19.0, WBC < 10,000; OR 2.79,95% CI 1.13–7.1). Proportional hazard regression analysis demonstrated that both statin therapy and WBC count predicted mortality. Conclusion: Patients undergoing PCI with LV dysfunction discharged on statins had improved survival regardless of WBC count, with a trend for greater improvement in patients with elevated WBC counts. In addition, WBC count predicts mortality in this high‐risk population with LV dysfunction undergoing PCI.