title: Statin use and clinical osteoarthritis in the general population: a longitudinal study.
abstract: BACKGROUND
  One hypothesis has posited whether abnormal lipid metabolism might be a causal factor in the pathogenesis of osteoarthritis (OA). Routine statin use in clinical practice provides the basis for a natural experiment in testing this hypothesis.
  
  
  OBJECTIVE
  To test the hypothesis that statins reduce the long-term occurrence of clinically defined OA.
  
  
  METHODS
  Cohort design with a 10-year follow-up.
  
  
  METHODS
  16,609 adults cardiovascular disease cohorts aged 40 years and over from the UK General Practice Research Database with data available to 31 December 2006.
  
  
  METHODS
  Statins were summarised as annual mean daily dose and dose change over two-year time periods.
  
  
  METHODS
  Incident episode of clinically defined osteoarthritis was assessed within 2 years, and at 4-year and 10-year follow-up time periods, using Cox and discrete time survival analysis. Covariates included age, gender, deprivation, body mass index, cholesterol level, pain-modifying drug co-therapies, and duration and severity of cardiovascular disease.
  
  
  RESULTS
  Higher therapeutic dose of statin, with a treatment duration of at least 2 years was associated with a significant reduction in clinical OA compared to non-statin users in the follow-up time period. The estimated adjusted rate ratios were as follows: lowest statin dose quartile 1: 2.5 (95 % CI 2.3, 2.9); quartile 2: 1.3 (1.1, 1.5); quartile 3: 0.8 (0.7, 0.95); and highest statin dose quartile 4: 0.4 (0.3, 0.5). The largest statin dose increments were associated with significant reductions estimated at 18 % in OA outcome within 2 years and 40 % after 4 years, compared to non-statin users.
  
  
  CONCLUSIONS
  This longitudinal study from a national clinical practice setting provides evidence that higher statin dose and larger statin dose increments were associated with a reduction in clinically defined OA outcome.
authors.affiliation: Health Services Research Unit, Innovation Centre 1, Keele University, Staffordshire, ST5 5NB, UK. u.kadam@keele.ac.uk
authors.forename: U T
authors.initials: UT
authors.lastname: Kadam
authors.forename: M
authors.initials: M
authors.lastname: Blagojevic
authors.forename: J
authors.initials: J
authors.lastname: Belcher
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000627:therapeutic use*; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D010003:Osteoarthritis / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology*; D011159:Population Surveillance / Q000379:methods*; D016896:Treatment Outcome
chemical_list: D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors