Risk of hospitalized rhabdomyolysis associated with lipid-lowering drugs in a real-world clinical setting

Background The occurrence of low rates of rhabdomyolysis among patients receiving lipid-lowering drugs (LLDs) in randomized clinical trials may be elucidated with population-based studies. Objective To determine the risk of hospitalized rhabdomyolysis associated with LLD therapy. Methods This observational study used claims data from 9 million members of five United States health plans to identify patients (≥18 years) who received >2 statin and nonstatin LLDs during July 2000 to December 2004. Inpatient International Classification of Diseases , Ninth Revision, Clinical Modification, codes for rhabdomyolysis (791.3, 728.89, and 728.88) were observed during the follow-up period; cases were confirmed with patients' medical records. Rhabdomyolysis events were reported per 10,000 person-years of LLD exposure; multivariate analysis was conducted. Results The study cohort (N = 473,343) received 490,988 and 11,624 person-years of LLD, and combination therapy, respectively. Medical charts were obtained for 104 of 144 eligible patients with rhabdomyolysis claims; 42 cases were confirmed. With atorvastatin as reference, rhabdomyolysis rates (95% confidence interval) were greatest for cerivastatin, 8.4 (2.3-21.7); no difference among available statins was observed. Rates for other LLD monotherapies were: niacin, 2.1 (0.3−7.7), ezetimibe, 2.1 (0.3−7.8), fenofibrate, 0 (0−1.7), and gemfibrozil, 2.0 (0.5−5.2). Multivariate analysis showed only cerivastatin with a significantly greater risk of rhabdomyolysis (odds ratio 4.74, 95% confidence interval 1.1-21.2, P = .041) versus atorvastatin among the statins. Combination therapies had increased rhabdomyolysis risk (OR 7.1, 1.6-31.6, P = .010) versus LLDs alone. Conclusion The risk of habdomyolysis among hospitalized patients receiving statins was low; no difference among the available statins was evident. Further data are needed to establish the risk profile but current findings already offer guidance to physicians.