Statin use and mortality in rheumatoid arthritis: a general population-based cohort study

Background Dual lipid-lowering and anti-inflammatory properties of statins may lead to survival benefits in patients with rheumatoid arthritis (RA). However, data on this topic are limited, and the role of statins in RA remains unclear. Objectives To examine the association of statin use with overall mortality among patients with RA in a general population context. Methods We conducted an incident user cohort study with time-stratified propensity score matching using a UK general population database. The study population included individuals aged >= 20 years who had a diagnosis of RA and had used at least one disease-modifying antirheumatic drug (DMARD) between January 2000 and December 2012. To closely account for potential confounders, we compared propensity score matched cohorts of statin initiators and comparators (non-initiators) within 1-year cohort accrual blocks. Results 432 deaths occurred during follow-up (mean 4.51 years) of the 2943 statin initiators for an incidence rate of 32.6/1000 person-years (PY), while the 513 deaths among 2943 matched comparators resulted in an incidence rate of 40.6/1000 PY. Baseline characteristics were well-balanced across the two groups. Statin initiation was associated with a 21% lower risk of all-cause mortality (HR=0.79, 95% CI 0.68 to 0.91). When we defined RA by its diagnosis code alone (not requiring DMARD use), the corresponding HR was 0.81 (95% CI 0.74 to 0.90). Conclusions Statin initiation is associated with a lower risk of mortality among patients with RA. The magnitude of association is similar to that seen in previous randomised trials among the general population.