Epidemiological survey of atrial fibrillation among the elderly population in rural areas of Shanghai

Abstract

Objective To investigate the prevalence of atrial fibrillation (AF) among the elderly population in rural areas of Shanghai. Methods A cross-sectional survey was conducted among 36,734 rural residents over 60 years old in Songjiang District of Shanghai in 2015. Patients with atrial fibrillation were screened by medical history and electrocardiogram. The enrolled subjects were divided into four age groups: 60 years~, 70 years~, 80 years~, and ≥90 years. Comparisons of the prevalence of AF between males and females in 36,734 rural residents over 60 years old, between men and women of the same age group, between different age groups of the same sex, and between rural residents over 65 years old in Liaoning Province and those in Songjiang District were performed by the chi-square test of four-fold table. Results The overall prevalence rate of AF in 36,734 rural residents over 60 years old in Songjiang District of Shanghai was 2.25%. The prevalence rate of AF in males (2.66%) was higher than that in females (1.95%) (χ2=20.704, P<0.001). For males, the prevalence rate of AF was 1.42% in the 60 years~ group, 3.42% in the 70 years~group, 5.81% in the 80 years~ group, and 6.49% in the≥90 years group; there was a significant difference among different age groups (χ2=135.586, P<0.001). For females, the prevalence of AF was 0.86% in the 60 years~ group, 2.24% in 70 years~ group, 5.02% in 80 years~ group, and 6.20% in the ≥90 years group; there was a significant difference among different age groups (χ2=223.249, P<0.001). Males had a higher AF prevalence rate than females in both the 60 years~ and 70 years~ groups (1.42% vs 0.86%, χ2=14.050, P<0.05; 3.42% vs 2.24%, χ2=18.406, P<0.05). The prevalence rate of AF in females over 65 years old in Liaoning Province was higher than that in Songjiang District of Shanghai (3.1% vs 2.04%, χ2=4.132, P=0.042); there was no significant difference in AF prevalence rate between males over 65 years old in these two areas (3.3% vs 2.89%, χ2=0.392, P=0.531). Conclusion The prevalence of AF increases with age in rural population over 60 years old in Songjiang District of Shanghai, with a significant difference between two sexes. The prevalence of AF in Chinese elderly rural population may have gender and regional differences. Key words: Atrial fibrillation; Epidemiological survey; Rural population