Relation of atrial fibrillation to glomerular filtration rate.

Although both atrial fibrillation (AF) and decreasing glomerular filtration rate (GFR) are strongly related to advanced age and share common associated vascular risk factors, few studies have explored the relation between AF and GFR. From residents (age >or=40 years) in Kurashiki City, a total of 41,417 subjects (median age 72 years; 13,956 men) were enrolled in the Kurashiki City Annual Medical Survey from May to December 2006. The estimated overall prevalence of AF was 1.6% (2.8% in the low-GFR tertile, 1.2% in the middle tertile, and 0.9% in the high tertile, p <0.001). After all subjects were categorized into age tertiles (age thresholds 68 and 76 years), AF was identified in 0.9% in the low-GFR tertile, 0.6% in the middle tertile, and 0.5% in the high tertile in the low-age tertile (p = 0.018); 2.6% in the low-GFR tertile, 1.2% in the middle tertile, and 1.1% in the high tertile in the middle-age tertile (p <0.001); and 3.9% in the low-GFR tertile, 2.4% in the middle tertile, and 1.7% in the high tertile in the high-age tertile (p <0.001). The odds ratio for AF adjusted for age, gender, vascular risk factors, cardiac disease, and hemoglobin was 1.91 (95% confidence interval 1.54 to 2.38, p <0.001) for the low-GFR tertile versus the high tertile and 1.12 (95% confidence interval 0.88 to 1.42, p = 0.364) for the middle-GFR tertile versus the high tertile. The prevalence of AF gradually increased with decreasing GFR. In conclusion, AF appears to be associated with decreasing GFR.