Objective: To investigate the risk of cardiovascular disease (CVD) in patients with rheumatoid arthritis (RA) treated with tumor necrosis factor (TNF) inhibitors, compared to a standard RA population.
Methods: Patients were recruited from a regional register, which includes over 90% of patients with RA started on TNF blockers in 1999 or later, and a local community based cohort of RA patients, established in 1997. Of a total of 983 patients in the combined cohort, 531 received treatment with etanercept or infliximab during the study period. The total cohort (n = 983) was linked with national registers for inpatient care and cause of death through December 31, 2001. CVD was defined as the first inpatient care or death from CVD without inpatient care for CVD prior to study entry. First CVD events in those treated versus not treated with TNF blockers were estimated, using age and sex adjusted incidence density computations with treatment and disease severity markers as time-dependent covariates.
Results: In the anti-TNF-treated patients, the age-sex adjusted incidence rate of first CVD event was 14.0/1000 person-years at risk (95% CI 5.7-22.4), compared with 35.4/1000 person-years (95% CI 16.5-54.4) in those not treated. Controlling for disability, the age-sex adjusted rate ratio was 0.46 (95% CI 0.25-0.85, p = 0.013) in anti-TNF-treated versus not treated.
Conclusion: These findings suggest that the risk of developing CVD is lower in patients with RA treated with TNF blockers. This is compatible with the hypothesis that inflammation contributes to the development of cardiovascular events.