Background/Purpose: Individuals with systemic autoimmune rheumatic diseases (SARDs)—such as systemic lupus erythematosus (SLE) and systemic sclerosis (SSc)—have been found to have an increased risk of premature cardiovascular (CV) disease compared with healthy peers. Statins have been shown to reduce CV events and mortality in the general population as well as among those with rheumatoid arthritis (RA).¹ However, it is not known whether statins have a similar impact among those with SARDs. We examined the potential survival benefit of statin use on mortality among patients with SARDs in a general population setting.

Methods: We conducted an incident user cohort study with time-stratified propensity score matching using a United Kingdom general population database. Our population included patients with a SARD as determined by incident diagnoses of SLE, SSc, Sjogren’s syndrome, dermatomyositis, polymyositis, mixed connective tissue disease, Behcet’s syndrome, or ANCA-associated vasculitis between January 1, 2000 and December 31, 2014. To account for potential confounders, we compared propensity score-matched cohorts of statin initiators and comparators (non-initiators) within 1-year cohort accrual blocks. 50 variables were used to create the propensity scores, including but not limited to disease duration, socio-economic status, body mass index, lifestyle factors, and medication use.

Results: Of 2310 statin initiators, 303 died during the follow-up period (mean=5.09 years), whereas among 2310 propensity score-matched non-initiators, 335 died during the follow-up period (mean=4.89 years). This corresponds to a mortality rate of 25.77/1000 and 29.64/1000 person-years, respectively. The baseline characteristics were well-balanced between the two groups. Statin initiation was associated with a 17% reduction of all-cause mortality (HR=0.83, 95% CI 0.70-0.996). When we compared the unmatched cohorts to determine the effectiveness of our propensity score matching, the statin initiators (n=2863) actually showed an 85% higher risk of mortality (HR=1.85, 95% CI 1.58-2.16) compared to non-initiators (n=2863 randomly selected without propensity score matching) due to confounding by indication.

Conclusion: In this general population-based cohort study, statin initiation was shown to reduce overall mortality in patients with SARDs after adjusting for relevant determinates of CV risk. This is similar to what has been shown in the general population and in patients with RA.¹ These findings suggest that statins should be considered part of the optimal CV risk-reduction strategy for patients with SARDs. Rheumatologists can advocate for this beneficial treatment intervention among their patients. References: 1. Schoenfeld SR et al. Statin use and mortality in rheumatoid arthritis: a general population-based cohort study. Ann Rheum Dis. 2016 Jul;75(7):1315-20.