title: Lack of association of oral calcium supplementation with coronary artery calcification in rheumatoid arthritis.
abstract: OBJECTIVE
  To investigate the association between oral calcium supplementation and coronary artery calcification among rheumatoid arthritis (RA) patients without known cardiovascular disease (CVD).
  
  
  METHODS
  This study was conducted as a nested, prospective cohort study of RA patients without known CVD. The daily supplemental calcium dose was ascertained from each patients' list of prescription and over-the-counter medications at baseline and at visit 2 (median 20 months postbaseline). The coronary artery calcium (CAC) score, a measure of coronary atherosclerosis, was assessed by cardiac multidetector row computed tomography at baseline and at visit 3 (median 39 months postbaseline). The association between calcium supplementation and CAC was explored.
  
  
  RESULTS
  Among the 145 RA patients studied, 42 (28%) were taking ≥1,000 mg/day of supplemental calcium at baseline. A CAC score of >100 units was seen in 44 patients (30%) at baseline and 50 patients (34%) at followup. Baseline CAC scores of >100 units were significantly less frequent in patients receiving the higher dosage (≥1,000 mg/day) of supplemental calcium than in those receiving the lower dosage (<1,000 mg/day) (odds ratio [OR] 0.28, 95% confidence interval [95% CI] 0.11-0.74); this association remained significant after adjustment for relevant confounders (adjusted OR 0.30, 95% CI 0.09-0.93). Similarly, at the third study visit, CAC scores of >100 units were less frequent in the higher supplemental calcium dose group compared to the lower dose group (OR 0.41, 95% CI 0.18-0.95); however, after adjustment for relevant confounders, the statistical significance of this association was lost (adjusted OR 0.39, 95% CI 0.14-1.12). No effect of sex heterogeneity was seen in the association of calcium supplementation with coronary artery calcification, and no change in the CAC score over time was observed.
  
  
  CONCLUSIONS
  Higher levels of oral calcium supplementation were not associated with an increased risk of coronary atherosclerosis, as measured by the CAC score, in this RA cohort.
authors: Columbia University, Department of Medicine, Division of Rheumatology, College of Physicians & Surgeons. New York, NY.
authors: Laura
authors: L
authors: Geraldino-Pardilla
authors: Columbia University, Department of Medicine, Division of Rheumatology, College of Physicians & Surgeons. New York, NY.
authors: Shanthi
authors: S
authors: Dhaduvai
authors: Columbia University, Department of Medicine, Division of Rheumatology, College of Physicians & Surgeons. New York, NY.
authors: Jon T
authors: JT
authors: Giles
authors: Columbia University, Department of Medicine, Division of Rheumatology, College of Physicians & Surgeons. New York, NY.
authors: Joan M
authors: JM
authors: Bathon
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001172:Arthritis, Rheumatoid / Q000453:epidemiology*; D002118:Calcium / Q000627:therapeutic use*; D016022:Case-Control Studies; D015331:Cohort Studies; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000453:epidemiology*; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography; D011446:Prospective Studies; D012307:Risk Factors; D061205:Vascular Calcification / Q000000981:diagnostic imaging / Q000453:epidemiology*
chemical_list: D002118:Calcium