[Causes of death and influencing factors of atrial fibrillation patients undergoing anticoagulation therapy].

Objective

To investigate the causes of death and predictors in patients with nonvalvular atrial fibrillation (AF) undergoing anticoagulation therapy.

Methods

Consecutive anticoagulated nonvalvular AF patients were recruited from the China Atrial Fibrillation Registry (China-AF) Study from August 2011 to December 2018. After exclusion of patients with hypertrophic cardiomyopathy, dilated cardiomyopathy, or loss of follow-up within 1 year, 2 248 patients were included in this analysis. Enrolled patients were followed up were followed up for 3 and 6 months, and then every 6 months. The primary endpoint was death, including cardiovascular death, non-cardiovascular death and undetermined death. The patients were divided into survival group and death group according to the survival status after follow-up. Clinical information such as age and sex was collected. Cox proportional hazards regression was performed to identify associated risk factors for all-cause mortality, and Fine-Gray competing risk model was used to identify associated risk factors for cardiovascular mortality.

Results

A total of 2 248 patients with atrial fibrillation receiving anticoagulant therapy died over a mean follow-up of (42±24) months, mean age was (67±10) years old and 41.1% (923/2 248) patients were female. The mortality rate was 2.8 deaths per 100 patient-years. The most common cause of death was cardiovascular deaths, accounted for 55.0% (120/218). Worsening heart failure was the most common cause of cardiovascular deaths (18.3% (40/218)), followed by bleeding events (12.9% (28/218)) and ischemic stroke (8.7% (19/218)). Multivariate Cox regression analysis showed that age (HR = 1.05, 95%CI 1.04-1.07, P<0.001), anemia (HR = 1.81, 95%CI 1.02-3.18, P = 0.041), heart failure (HR=2.40, 95%CI 1.75-3.30, P<0.001), ischemic stroke/transient ischemic attack (TIA)(HR = 1.59, 95%CI 1.21-2.13, P = 0.001) and myocardial infarction (HR = 2.93, 95%CI 1.79-4.81, P<0.001) were independently associated with all-cause death. Fine-Gray competing risk model showed that age (HR=1.05, 95%CI 1.02-1.08, P<0.001), heart failure (HR=2.81, 95%CI 1.79-4.39, P<0.001), ischemic stroke/TIA (HR=1.50, 95%CI 1.02-2.22, P=0.041) and myocardial infarction (HR=3.31, 95%CI 1.72-6.37, P<0.001) were independently associated with cardiovascular death.

Conclusions

In anticoagulated nonvalvular AF patients, ischemic stroke represents only a small subset of deaths, whereas worsening heart failure is the most common cause of cardiovascular deaths. Heart failure, ischemic stroke/TIA, and myocardial infarction are associated with increased mortality.