title: Incidence of hospitalized rhabdomyolysis with statin and fibrate use in an insured US population.
abstract: BACKGROUND
  The incidence of hospitalized rhabdomyolysis is not well characterized among patients taking statin-fibrate combination therapies.
  
  
  OBJECTIVE
  To estimate and compare the rates of hospitalized rhabdomyolysis during periods of exposure to different statins and fibrates.
  
  
  METHODS
  We retrospectively identified a cohort of patients who initiated a statin or fibrate between January 1, 1998, and December 31, 2007, using a database of a large US health insurer. Patients were followed for the occurrence of hospitalized rhabdomyolysis, determined by clinical review of medical records. Exposure status during the study period was determined by electronic records of statin and fibrate dispensing. Incidence rates (IRs) and incidence rate ratios (IRRs) for various combinations of fibrate and statin exposure were modeled, using Poisson regression.
  
  
  RESULTS
  There were 1,116,805 patients who initiated statin and/or fibrate therapy, with 2.4 million person-years of observation. Seventy cases of hospitalized rhabdomyolysis were confirmed. Adjusted analyses showed a persistent increased risk of rhabdomyolysis with combination therapy, while statin and fibrate therapy alone showed similar, nonsignificant increases in risk. The adjusted IRR for a statin and fenofibrate was 3.26 (95% CI 1.21 to 8.80), while the adjusted IRR for a statin and gemfibrozil was 11.93 (95% CI 3.96 to 35.93) versus statin therapy alone. The individual IRs for statin monotherapy ranged from 0.00 to 3.34 per 100,000 person-years. The number needed to harm was lower for combination statin-gemfibrozil therapy (2753) compared with that for statin therapy alone (454,545).
  
  
  CONCLUSIONS
  The incidence of hospitalized rhabdomyolysis is rare, but higher in patients with concomitant statin-fibrate treatment than in patients on statin therapy alone. The rate found in this study is consistent with the known profile of the statin-fibrate treatment option for mixed dyslipidemia.
authors.affiliation: Epidemiology Division, OptumInsight, Ann Arbor, MI, USA. kandace.amend@innovus.com
authors.forename: Kandace L
authors.initials: KL
authors.lastname: Amend
authors.forename: Joan
authors.initials: J
authors.lastname: Landon
authors.forename: Veena
authors.initials: V
authors.lastname: Thyagarajan
authors.forename: Steve
authors.initials: S
authors.lastname: Niemcryk
authors.forename: Andrew
authors.initials: A
authors.lastname: McAfee
mesh_terms: D015331:Cohort Studies; D016208:Databases, Factual; D004359:Drug Therapy, Combination / Q000009:adverse effects; D050171:Dyslipidemias / Q000188:drug therapy; D057286:Electronic Health Records; D005260:Female; D011345:Fenofibrate / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D005500:Follow-Up Studies; D015248:Gemfibrozil / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D006760:Hospitalization; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D000960:Hypolipidemic Agents / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D015994:Incidence; D007348:Insurance, Health; D008297:Male; D017891:Pharmacoepidemiology / Q000379:methods; D012189:Retrospective Studies; D012206:Rhabdomyolysis / Q000139:chemically induced* / Q000453:epidemiology / Q000628:therapy; D012306:Risk; D014481:United States / Q000453:epidemiology
chemical_list: D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D000960:Hypolipidemic Agents; D015248:Gemfibrozil; D011345:Fenofibrate