Abstract: Objective To explore the relationship between atrial fibrillation (AF) and homocysteine (Hcy) in the Chinese elderly. Methods The data were obtained from the survey of the population aged 70-89 years old in the fourth follow-up of Rugao Aging Cohort Study. According to the quartile level or the recommended cut point (15 μmol/L) of Hcy, the subjects were devided into Q1 group, Q2 group, Q3 group and Q4 group or high level of Hcy group and normal level of Hcy group. The relationships between different levels of Hcy and AF were analyzed by Logistic regression model. Results A total of 1798 subjects were included in this study, and the average age was 79.09±4.38 years old. Among them, 814 were male and 984 were female; 90 cases presented with AF (5.0%), and 867 cases presented with high level of Hcy (48.2%). There were statistically significant differences in age, smoking history, drinking history, Hcy level and the proportion of people with high Hcy level between AF group and non-AF group (P<0.05). Logistic regression analysis showed that, compared with Q1 group, the risk of AF in Q2 group (OR=2.884, 95%CI: 1.201-6.930), Q3 group (OR=3.644, 95%CI: 1.547-8.580) and Q4 group (OR=6.607, 95%CI: 2.932-14.891) were significantly increased; Compared with normal level of Hcy group, the risk of AF in high level of Hcy group was significantly increased (OR=2.774, 95%CI: 1.742-4.419); For each standard deviation increased in logHcy, the risk of AF was 1.441 times as high as the original one (OR=1.441, 95%CI:1.227-1.692); The differences were still statistically significant after adjusting for age, gender, marital status, body mass index, education, occupation, smoking, drinking, hypertension and diabetes (P<0.05). Conclusions Elevated Hcy level is correlated with the increased risk of AF in the Chinese elderly, and it suggests that Hcy may be a risk factor for the occurrence of AF.

Key words: atrial fibrillation, homocysteine, aged