Objective: To evaluate whether statins are associated with a protective effect on the development of rheumatoid arthritis (RA).
Methods: We conducted a nested case-control study using data from the General Practice Research Database. We identified a study population consisting of three groups of subjects aged 40 to 89 years; 1) patients exposed to a statin or other lipid lowering agent (LLA) 2) patients with a diagnosis of hyperlipidemia in the absence of lipid-lowering drug treatment, and 3) a random sample of 25,000 people with no diagnosis of hyperlipidemia nor a prescription for a lipid-lowering drug. From this population we identified incident cases of RA and up to 4 controls for each case, matched on age, sex, general practice, number of years of recorded history in the database, and index date. We evaluated the independent effects of hyperlipidemia and statins on the development of RA using conditional logistic regression.
Results: We identified 313 cases of RA and 1252 matched controls. Compared to patients with untreated hyperlipidemia, or hyperlipidemia treated with LLAs other than statins, the adjusted OR for patients with no hyperlipidemia was 0.68 (95% CI 0.50-0.91). When we compared those with hyperlipidemia who received statins to those with hyperlipidemia who did not use statins (i.e. untreated hyperlipidemia patients or those treated with non-statin LLAs) the OR was 0.59 (95% CI 0.37 – 0.96).
Conclusion: These data provide evidence to support the hypothesis that statins may be protective against the development of RA in those with hyperlipidemia.