Effect of body mass fluctuation on the prognosis of atrial fibrillation

Abstract

Objective To investigate the effect of body mass fluctuation on the prognosis of patients with atrial fibrillation. Methods The patients diagnosed with atrial fibrillation in the People′s Hospital of Xinjiang Uygur Autonomous Region from 2012 to 2014 were selected.Among the 540 patients, the patients were divided into normal body(BMI ≤ 25 kg/m2), overweight (25 kg/m2<BMI<30 kg/m2) and obesity (BMI ≥ 30 kg/m2) according to the baseline body mass.The median body mass fluctuation of the three groups was 2.40 kg, and according to the median body mass fluctuations, the patients were divided into two groups: the high body mass fluctuation group and the low body mass fluctuation group.Changes of body mass were observed and the incidence of cardiac death, acute coronary syndrome, chronic heart failure, cerebral embolism and peripheral vascular embolization were monitored. Results During the follow-up period, as the increased of body mass fluctuation, the incidence rate of end point events also increasing continuously.The main end point event was used as the composite end point (HR(95%CI): 1.03 (1.06~1.15); P=0.02), including the cardiogenic death (HR(95%CI): 1.04 (1.09~1.12); P=0.03), the incidence of acute coronary syndrome (HR(95%CI): 1.04 (0.96~1.08); P=0.06) and the heart failure incidence (HR(95%CI): 95%CI: 1.04 (1.01~1.09), P=0.04). The secondary endpoint as composite endpoint (HR(95%CI): 1.16 (1.15~1.31); P=0.01), including the cerebral embolism (HR(95%CI): 1.21 (1.23~1.54); P=0.01) and the peripheral vascular embolism (HR(95%CI): 1.03 (0.91~1.03); P=0.01). After adjusting for all confounding factors, the quartile group with the highest body mass fluctuations was 6.2% higher in the main endpoint event than the lowest body quartile and 14.2% higher in the secondary endpoint.The occurrence of major endpoint events and secondary endpoint events in the quadruple group with high body mass fluctuation was significantly higher than that in the quadruple group with the lowest body mass fluctuation(main endpoint: 4.4% vs 10.6%; (HR(95%CI): 1.86 ( 1.53 ~ 2.41); P<0.01; secondary endpoints: 15.6% vs 29.8%; (HR(95%CI) 2.12 (1.56 ~ 3.58); P<0.01). The main endpoint events were cardiogenic death (HR(95%CI): 1.85 (1.73~2.3); P<0.01); incidence of acute coronary syndrome (HR(95%CI): 1.02 (0.94~1.35); P=0.08); incidence of heart failure (HR(95%CI): 1.48 (1.28~1.62); P<0.01); secondary endpoint events were cerebral embolism (HR(95%CI): 2.23 (1.93~3.91). (P<0.01), peripheral vascular embolism (HR(95%CI): 1.05 (0.96~1.42); P=0.13). For patients with normal body mass, body mass fluctuations had no significant effect on prognosis (main endpoints: 6.1% vs 5.3%; (HR(95%CI): 1.04 (0.94 ~ 1.43); P=0.064; secondary endpoint : 16.7% vs 17.4%; (HR(95%CI): 1.12 (0.84~ 1.09); P=0.072), but for overweight and obese patients, the greater the fluctuation of body mass, the higher the incidence of adverse events (main endpoint: super-recombination: 5.8% vs 11.2%; (HR(95%CI): 1.532 (1.135 ~ 3.156); P<0.001; obese group: 8.3% vs 15.1%; (HR(95%CI): 1.584 (1.258~3.489); P<0.001; secondary end points: super recombination: 17.1% and 21.3%; (HR(95%CI): 341.00 ( 1.132~ 1.984); P=0.013; obese group: 19.4% and 25.2%; (HR(95%CI): 1.315 (1.128~2.123); P=0.018). Conclusion Body mass fluctuations can significantly affect the prognosis of patients with atrial fibrillation and has a greater impact on patients with overweight and obesity. Key words: Atrial Fibrillation; Body mass; Fluctuations; Prognosis