Rheumatoid arthritis (RA) is an autoimmune disease that is mainly treated with various non-biologic and biologic disease modifying anti-rheumatic drugs (DMARDs). RA patients experience cardiovascular diseases (CVD) at a higher rate compared to the general population. Biologic DMARDs that inhibit the effects of the pro-inflammatory cytokine, tumor necrosis factor (TNF)-α which is implicated in various atherosclerotic processes, may reduce the risk of CVD. Very little evidence exists evaluating the association between TNF-inhibitors (TNF-Is) and CVD in early RA patients. Using data from Truven's MarketScan claims database for the period of 2007-2010, we first examined the factors influencing treatment with biologics in RA patients in a retrospective cohort study. We observed that treatment initiation with biologics in RA patients is associated with patient age, RA severity, RA type, pre-index non-biologic DMARD and steroid use, health insurance type, and drug benefit generosity. Neither the presence of cardiovascular risk factors, hypertension, hyperlipidemia or diabetes nor the history of CVD, including acute myocardial infarction, chronic heart failure, stroke or other CVD, were found to be associated with the initiation of biologic treatments. We then evaluated the impact of treatment with TNF-Is on the risk of incident CVD events in patients newly diagnosed with RA using a nested case-control design with incidence density sampling. We observed that the risk of an incident CVD event was reduced by current treatment with TNF-Is and non-biologic DMARDs compared to no treatment with DMARDs. Further, we observed that this protective effect was found to be associated with the duration of TNF-I and non-biologic DMARD use in a linear manner. Finally, we examined the independent effects of infliximab, adalimumab and etanercept on the risk of CVD in the same cohort. We observed that treatment with adalimumab, but not with infliximab and etanercept, was found to be associated with a reduced risk of incident CVD events compared to no treatment with DMARDs. In conclusion, we observed that early TNF-I or non-biologic DMARD treatment may play a vital role in reducing the increased CVD burden in RA patients, potentially by producing favorable changes in traditional cardiovascular risk factors and RA risk factors.Doctor of Philosoph
