Serum High-Sensitivity C-Reactive Protein Levels and the Risk of Atrial Fibrillation in Japanese Population: the Circulatory Risk in Communities Study

Aim: This study aimed to investigate the association between the serum high-sensitivity C-reactive protein (hs-CRP) levels and incident atrial fibrillation risk in the general Japanese population, who have lower hs-CRP levels than the Western population, and assess whether the association is modified by sex, overweight, hypertension, and smoking status. Methods: We conducted a prospective study in 6517 Japanese men and women aged 40-79 years without atrial fibrillation at baseline and enrolled in the Circulatory Risk in Communities Study (2002-2008). The hs-CRP levels were measured using the latex particle-enhanced immunonephelometric assay. Atrial fibrillation was identified using standard 12-lead electrocardiograms and information on physician-diagnosed atrial fibrillation history from the follow-up surveys. We used a Cox proportional hazard regression stratified by community. Results: During a median follow-up of 11 years, 127 new cases of atrial fibrillation (74 and 53 cases among men and women, respectively) were found. Compared to the lowest quintile of hs-CRP levels, the multivariable hazard ratios (95% confidence intervals) were 2.54 (1.17-5.50), 2.28 (1.06-4.93), 2.92 (1.37-6.23), and 2.77 (1.30-5.91) for the second, third, fourth, and fifth (highest) quintiles, respectively. There was no significant effect modification by sex, overweight, hypertension, and smoking status (P for interaction >0.05). Conclusions: Elevated hs-CRP levels were significantly associated with increased risk of atrial fibrillation in the Japanese population. The association of hs-CRP levels with incident atrial fibrillation did not vary according to sex, overweight, hypertension status, or smoking status.