Association between hyperuricemia and atrial fibrillation in rural China: a cross-sectional study

Background: To explore the association between atrial fibrillation (AF) and serum uric acid (SUA) in a general population in rural China. Methods: From January 2013 to August 2013, we performed a cross-sectional study involving 11,956 permanent residents >= 35 years old in the rural Liaoning province of China. All participants completed a questionnaire, had a physical examination, and underwent an electrocardiogram (ECG) and echocardiogram. AF was diagnosed from ECG findings and/or a history of physician-confirmed AF. Blood samples were drawn for laboratory analyses and hyperuricemia was defined as an SUA level > 7.0 mg/dL in men and > 5.7 mg/dL in women, based on the NHANES-III laboratory definition. Logistic regression analyses were performed to estimate the crude and independent associations between hyperuricemia and the prevalence of AF. Results: A total of 139 participants were diagnosed with AF, of which, 72 were self-reported, 45 were ECG-diagnosed, and 22 were both. There was a higher prevalence of AF in participants with hyperuricemia than those with normal SUA levels (2.4 vs. 1.0 %; P < 0.001). The odds ratios (OR) and 95 % confidence intervals (CI) were 2.37 (1.61-3.49) when compared to participants with normal SUA. After adjustment for other cardiovascular and AF risk factors, the independent association remained (OR = 1.94, 95 % CI: 1.26-3.00). Similar associations were observed between SUA as a continuous variable and AF prevalence (adjusted OR = 1.20, 95 % CI: 1.06-1.36). The independent associations were significant in men (Ps < 0.05) but not in women (Ps > 0.05), although the interaction logistic regression analyses presented these differences as not being statistically significant (Ps > 0.05). Conclusions: SUA is positively associated with the prevalence of AF in rural China.