Objective: This study evaluates whether depression is a risk factor for incident myocardial infarction (MI) in Department of Veterans Affairs (VA) patients with rheumatoid arthritis (RA) between 30 and 79 years of age.
Methods: We used a retrospective cohort study of 15,634 patients with RA. Diagnoses and sociodemographic data were obtained from VA administrative and pharmacy databases between fiscal years 1999 and 2006. Entry into the cohort required 2 years of patient time with no evidence of cardiovascular disease. Cox proportional hazard models with time-dependent covariates were computed to determine whether RA patients with depression as compared to RA patients without depression were at increased risk for MI during the maximum 6-year follow-up period.
Results: Unadjusted analyses indicated depressed RA patients were 1.4 times more likely than nondepressed RA patients to have an MI during follow-up. These results remained significant (HR=1.4; 95% CI: 1.1-1.8) in the adjusted Cox proportional hazards model which included the effects of sociodemographics and known physical risks (e.g., diabetes) for MI.
Conclusions: Depressed RA patients, without a history of cardiovascular disease, are 40% more likely to have a heart attack as compared to those without depression. These data demonstrate a rapid (within 6 years) transition to MI following onset of depression in RA patients. Increased monitoring of depression and heart disease status in this patient population may be warranted which in turn may result in longer duration of life.