PDB1 STATIN USE AND MORTALITY IN RHEUMATOID ARTHRITIS: AN INCIDENT USER COHORT STUDY

Abstract

Patients with rheumatoid arthritis (RA) have higher rates of mortality. Previous research indicates that treatment with statin therapy may play a role in reducing the mortality rate of patients with RA but literature is scarce and limited. Thus, the objective of this study was to further our understanding of the association between statin use and overall mortality among RA patients. An incident user cohort study using data from University of Utah Data Warehouse was conducted. Patients aged ≥18 years with a diagnosis of RA between January 2007 and December 2015 were included and reviewed for the use of statin medication. Individuals were excluded if they were current or prior statin users or if they had incomplete records of any covariate. Time stratified propensity score matching was utilized to adequately balance ‘Statin User’ and ‘Statin Non-User’ groups in 1-year blocks to account for potential confounders. Cox proportional hazard models was used to estimate the association and cumulative hazard plots were generated as estimates of cumulative mortality to identify time trends. The mean age for the comparable groups (N=1,883 each) was 60 years and majority of the sample were females. There were 156 deaths during follow up (mean=5.30 years) of the 1,883 statin non initiators for an incidence rate of 15.61/1000 person-years (PY), while there were 123 deaths during follow up (mean=6.08 years) of 1,883 matched comparators resulting in an incidence rate of 10.73/1000 PY. The hazards ratio for all-cause mortality in patients with rheumatoid arthritis for statin users was 0.70 (95% CI 0.55 – 0.89; p <0.001) compared to non-statin users. Compared with non-use of statins, current statin use is associated with 30% lower risk of mortality in RA patients. The utility of statins in this population supports integration into the current guidelines.