title: Association of vitamin D and incident statin induced myalgia--a retrospective cohort study.
abstract: OBJECTIVE
  Evidence is conflicting with regards to the role of vitamin D in statin induced myalgia (SIM). Studies so far have assessed cross-sectional association and were limited by study sample selected predominantly from cardiology clinics. In this retrospective cohort study we assessed the association between vitamin D and SIM and attempted to establish a serum vitamin D cutoff to identify patients at risk for developing SIM.
  
  
  METHODS
  Medical charts of 5526 consecutive patients from a primary care practice in Scranton, Pennsylvania from 2005-2012 were reviewed. Vitamin D level (25-hydroxy cholecalciferol) at statin initiation was considered "Exposure level". Vitamin D levels were categorized into quartiles (≤ 10, 11-20, 21-30, >30 ng/ml). SIM was identified by patient report.
  
  
  RESULTS
  1160 out of 5526 patients were treated with statins. The mean age was 55.9 years. 276 (24%) developed SIM. Unadjusted 7-yr cumulative incidences of SIM for quartiles 1-4 of vitamin D were 32.3, 21.5, 18.3 and 14.6% respectively. The lowest quartile of vitamin D was independently associated with 1.21 times the hazard of the fourth quartile for developing SIM (95% CI: 1.09, 1.33; P-trend  = 0.001). Vitamin D cut-off ≤15 ng/ml, showed a positive predictive value, negative predictive value, likelihood ratio (LR) + and LR- of 81, 90, 5.1 and 0.1, respectively for predicting SIM.
  
  
  CONCLUSIONS
  Low vitamin D level at statin initiation is associated with SIM, levels ≤15 ng/ml have a high predictive accuracy for SIM. Randomized controlled trials are needed to validate our results.
authors.affiliation: Department of Internal Medicine, The Wright Center for Graduate Medical Education, Scranton, Pennsylvania, United States of America.
authors.forename: Ghanshyam
authors.initials: G
authors.lastname: Palamaner Subash Shantha
authors.affiliation: Department of Internal Medicine, The Wright Center for Graduate Medical Education, Scranton, Pennsylvania, United States of America.
authors.forename: Julio
authors.initials: J
authors.lastname: Ramos
authors.affiliation: Department of Internal Medicine, The Wright Center for Graduate Medical Education, Scranton, Pennsylvania, United States of America.
authors.forename: Linda
authors.initials: L
authors.lastname: Thomas-Hemak
authors.affiliation: Department of Cardiovascular Medicine, The Wright Center for Graduate Medical Education, Scranton, Pennsylvania, United States of America.
authors.forename: Samir Bipin
authors.initials: SB
authors.lastname: Pancholy
mesh_terms: D000368:Aged; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000009:adverse effects*; D015994:Incidence; D008297:Male; D008875:Middle Aged; D063806:Myalgia / Q000097:blood / Q000139:chemically induced* / Q000453:epidemiology*; D010414:Pennsylvania / Q000453:epidemiology; D012189:Retrospective Studies; D014807:Vitamin D / Q000097:blood*; D014808:Vitamin D Deficiency / Q000097:blood / Q000453:epidemiology*
chemical_list: D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D014807:Vitamin D