It is hypothesized that the systemic inflammation associated with rheumatoid arthritis (RA) promotes an increased risk of cardiovascular (CV) morbidity and mortality. We examined the risk and determinants of congestive heart failure (CHF) in patients with RA.
We assembled a population-based, retrospective incidence cohort from among all individuals living in Rochester, Minnesota, in whom RA (defined according to the American College of Rheumatology 1987 criteria) was first diagnosed between 1955 and 1995, and an age- and sex-matched non-RA cohort. After excluding patients in whom CHF occurred before the RA index date, all subjects were followed up until either death, incident CHF (defined according to the Framingham Heart Study criteria), migration from the county, or until January 1, 2001. Detailed information from the complete medical records (including all inpatient and outpatient care provided by all local providers) regarding RA, ischemic heart disease, and traditional CV risk factors was collected. Cox models were used to estimate the effect of RA on the development of CHF, adjusting for CV risk factors and/or ischemic heart disease.
The study population included 575 patients with RA and 583 subjects without RA. The CHF incidence rates were 1.99 and 1.16 cases per 100 person-years in patients with RA and in non-RA subjects, respectively (rate ratio 1.7, 95% confidence interval [95% CI] 1.3-2.1). After 30 years of followup, the cumulative incidence of CHF was 34.0% in patients with RA and 25.2% in non-RA subjects (P< 0.001). RA conferred a significant excess risk of CHF (hazard ratio [HR] 1.87, 95% CI 1.47-2.39) after adjusting for demographics, ischemic heart disease, and CV risk factors. The risk was higher among patients with RA who were rheumatoid factor (RF) positive (HR 2.59, 95% CI 1.95-3.43) than among those who were RF negative (HR 1.28, 95% CI 0.93-1.78).
Compared with persons without RA, patients with RA have twice the risk of developing CHF. This excess risk is not explained by traditional CV risk factors and/or clinical ischemic heart disease.