Association between statin use and mortality in patients with implantable cardioverter-defibrillators and left ventricular systolic dysfunction

BackgroundA few previous nested cohort trials have evaluated the use of statins on survival and the occurrence of ventricular tachycardia or fibrillation (VT/VF). While the studies generally agreed on the survival effects, they disagreed on the magnitude of the mortality benefit and on the effect on VT/VF.ObjectiveThe purpose of this study was to determine in a large, long-term follow-up cohort whether statin therapy could reduce mortality and the occurrence of VT/VF in a mixed population receiving an implantable cardioverter-defibrillator (ICD) for primary or secondary prevention and either ischemic or nonischemic cardiomyopathy.MethodsCohort evaluation of all patients undergoing implantation of an ICD with a left ventricular ejection fraction <40% at an urban U.S. teaching hospital from December 1997 through January 2007. Multivariable analysis of predictors of mortality and VT/VF were conducted.ResultsThere were 314 deaths among the 1204 patients (26.1%). The use of statin therapy (n = 642) was associated with an adjusted hazard ratio of 0.67 (95% confidence interval [CI] 0.53–0.85; P<.001) for mortality as compared with the no-statin group (n = 562). The use of statin therapy was not associated with a reduction in the adjusted hazard ratio for VT/VF (0.85; 95% CI 0.68–1.06; P = .14).ConclusionsStatin therapy is associated with a reduction in overall mortality in patients with ischemic or nonischemic cardiomyopathy with an ICD implanted for either primary or secondary prevention. The magnitude of survival benefit might have been underestimated given our inability to use statin as a time-dependent covariate.