Continuation of statin therapy and a decreased risk of atrial fibrillation/flutter in patients with and without chronic kidney disease

Background: To contain cost, Taiwan's previous National Health Insurance Reimbursement Policy requested that physicians discontinue their patients' statin therapy once the serum cholesterol had reached appropriate levels. This allowed us to evaluate the association between statin continuation and the occurrence of atrial fibrillation/flutter and whether it was modified by chronic kidney disease (CKD) status. Methods: Patients who initiated statin therapy between January 1, 2001 and December 31, 2009 were identified from a random sample of one million subjects in the Taiwan National Health Insurance Research Database. The outcome was atrial fibrillation/flutter. A proportional hazard regression model with time-varying statin use was applied to estimate the hazard ratios (HR) and 95% confidence intervals (CIs) for atrial fibrillation/flutter according to current statin use versus treatment discontinuation, adjusted for baseline disease risk scores and time-varying covariates. Results: A total of 6767 CKD and 63,678 non-CKD patients initiating statin therapy were included and followed for an average of 4.0 years. A total of 1118 participants experienced new-onset atrial fibrillation/flutter. The incidence of atrial fibrillation/flutter was approximately 2 fold higher in the CKD patients. Continuation of statin therapy was associated with a 22% (adjusted hazard ratio 0.78; 95% CI: 0.65-0.93) and 57% (adjusted HR 0.43; 95% CI: 0.27-0.68) decrease in atrial fibrillation/flutter hazard as compared with discontinuation in non-CKD and CKD patients, respectively. Conclusions: Continuation of statin therapy was associated with a decreased risk of atrial fibrillation/flutter among CKD and non-CKD patients. However, further randomized studies are still needed to assess the association. (C) 2013 Elsevier Ireland Ltd. All rights reserved.