Use of statins and the risk of rheumatoid arthritis.

Jong, H. de, Klungel, O., Dijk, L. van, Vandebriel, R., Leufkens, H., Cohen Tervaert, J.W., Lovenren, H. van. Use of statins and the risk of rheumatoid arthritis. Pharmacoepidemiology and Drug Safety: 2009, 18(suppl. 1) S 126. Abstract: 25th International Conference on Pharmacoepidemiology and Therapeutic Risk Management. Providence, 16-19 augustus 2009.
Background: Statins exert immunomodulatory effects which can cause immune-dysregulation and potentially lead to autoimmune reactions. Objectives: To study the association between use of statins and the risk of incident rheumatoid arthritis (RA). Methods: We conducted a case-control study using The Netherlands Information Network of General Practice (LINH), including longitudinal data on prescriptions and their indications from medical records. We identified cases 16 years of age or older with a first-time diagnosis of RA in the period 2001–2006. To validate the first-time diagnosis of RA, patients had to have a referral to a specialist or one prescription of DMARD or more than two prescriptions of corticosteroids after the date of first diagnosis (index date). We
matched five controls to each RA case on age, and sex and assigned controls to the index date of the case to whom they were matched. Current use of statins was defined as a prescription within 6 months prior to the diagnosis of RA. We used conditional logistic regression to calculate odds ratios (OR) and adjusted for NSAIDs, corticosteroids, DMARD, BMI, hypertension, cardiovascular disease, hormone replacement therapy, proton pump inhibitors, and antibiotics. Results: We identified 1.012 cases and 4.740 controls. Median age of the patients was 58.6 years. Cases were more current users of statins (20.6%) compared to controls (10.4%). Compared to never use and after adjustment for potential confounders, current use of statins was asscociated with an increased risk of RA (OR=1.50; 95% CI: 1.05–2.13). Past use of statins was not associated with the risk of RA. Conclusions: Current use of statins was associated with an increased risk of developing RA.