Hyperuricemia is an independent competing risk factor for atrial fibrillation

Abstract

Backgrounds: The relationship between serum uric acid (SUA) and atrial fibrillation (AF) remains unclear because many parameters and diseases influence AF. This study was conducted to clarify the role of hyperuricemia as an independent competing risk factor for AF in an apparently healthy general population.

Methods: We retrospectively analyzed the medical records of 90,143 Japanese subjects who underwent annual regular health check-up in St. Luke's International Hospital, Tokyo, between January 2004 and June 2010. Of those subjects, 291 (0.32%) were identified as having AF by 12 leads electrocardiography. First, we analyzed 90,117 subjects to clarify the independent competing risk factors for AF and obtained odds ratios (ORs) by logistic regression analysis. Second, we excluded 40,825 subjects with hypertension, diabetes mellitus, dyslipidemia, chronic kidney disease, and current medication for hyperuricemia and/or gout, and we analyzed 49,292 subjects.

Results: First, AF groups were significantly higher SUA level (OR: 1.35; 95% confidence interval (CI), 1.22-1.50) than non-AF group. OR of hyperuricemia (>7.0mg/dL of SUA) for AF was 2.75 (95% CI, 2.10-3.60). Second, after multiple adjustments, higher SUA level (OR: 1.53; 95% CI, 1.21-1.92) was a significantly independent competing risk factor for AF, as well as older age, male sex, higher body mass index, lower FEV1/FVC, and higher hemoglobin. OR of hyperuricemia for AF was 3.19 (95% CI, 1.81-5.62).

Conclusions: Hyperuricemia is an independent competing risk factor for AF. Further prospective intervention studies are needed to prove whether lowering SUA level might be important for preventing AF or not.

Keywords: Atrial fibrillation; Clinical epidemiology; Competing risk factor; Uric acid.