Inflammation as a Risk Factor for Atrial Fibrillation

TLDR

Systemic inflammation marked by elevated C‑reactive protein has been linked to persistent atrial fibrillation. In the Cardiovascular Health Study, 5,806 participants had baseline CRP measured and were followed for an average of 6.9 years, with AF identified through self‑report, ECGs, and discharge codes and analyzed via univariate and multivariate models to evaluate CRP as a predictor of current and incident AF. Higher baseline CRP levels were associated with a greater prevalence of AF (adjusted OR 1.8 for the highest quartile) and independently predicted future AF incidence (adjusted hazard ratio 1.31 for the highest quartile, 1.24 per SD increase), indicating CRP may identify patients at increased risk for developing AF.

Abstract

The presence of systemic inflammation determined by elevations in C-reactive protein (CRP) has been associated with persistence of atrial fibrillation (AF). The relationship between CRP and prediction of AF has not been studied in a large population-based cohort.CRP measurement and cardiovascular assessment were performed at baseline in 5806 subjects enrolled in the Cardiovascular Health Study. Patients were followed up for a mean of 6.9+/-1.6 (median 7.8) years. AF was identified by self-reported history and ECGs at baseline and by ECGs and hospital discharge diagnoses at follow-up. Univariate and multivariate analyses were used to assess CRP as a predictor of baseline and future development of AF. At baseline, 315 subjects (5%) had AF. Compared with subjects in the first CRP quartile (<0.97 mg/L), subjects in the fourth quartile (>3.41 mg/L) had more AF (7.4% versus 3.7%, adjusted OR 1.8, 95% CI 1.2 to 2.5; P=0.002). Of 5491 subjects without AF at baseline, 897 (16%) developed AF during follow-up. Baseline CRP predicted higher risk for developing future AF (fourth versus first quartile adjusted hazard ratio 1.31, 95% CI 1.08 to 1.58; P=0.005). When treated as a continuous variable, elevated CRP predicted increased risk for developing future AF (adjusted hazard ratio for 1-SD increase, 1.24; 95% CI 1.11 to 1.40; P<0.001).CRP is not only associated with the presence of AF but may also predict patients at increased risk for future development of AF.