Causes of death and influencing factors of atrial fibrillation patients undergoing anticoagulation therapy / 中华心血管病杂志

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.

The thromboembolism risk of low-risk atrial fibrillation patients with different clinical characteristics / 中华心血管病杂志

Objective: This study explored the thromboembolism risk of low-risk atrial fibrillation (AF) patients (CHA2DS2-VASc score of 0 or 1 for male and 1 or 2 for female) with different clinical characteristics to provide the basis for anticoagulation decision-making in these patients. Methods: We prospectively enrolled consecutive 2 862 nonvalvular low-risk AF patients between August 2011 to December 2018 in China-AF (China Atrial Fibrillation Registry) Study, their CHA2DS2-VASc score was 0 or 1 for male and 1 or 2 for female. According to their age, sex, presence or absence of hypertension, diabetes mellitus, congestive heart failure, and vascular disease at the time of enrolling, patients were divided into CHA2DS2-VASc score 0 score group, 1 score group, and 2 score group. Patients were followed up every 6 months by outpatient clinic visit or telephone interview. The outcome was a thromboembolic event, including ischemic stroke and systemic embolism. Univariate Cox regression analysis was used to compare the thromboembolism risk between the patients with different risk factors and CHA2DS2-VASc score 0 group. Results: A total of 2 862 low-risk atrial fibrillation patients were enrolled in this study. 915 patients (32.0%) were female, and age was (55.0±10.7) years old. There were 933 patients (32.6%) in CHA2DS2-VASc score 0 group, 1 401 patients (49.0%) in score 1 group and 528 patients (18.5%) in score 2 group. During follow-up (median 1.5 years, 5 811.82 person-years), 33 cases of thromboembolic events were recorded, the annual rate of thromboembolism was 0.57% (95%CI 0.40%~0.80%). The number of thromboembolic events in patients with CHA2DS2-VASc score 0, 1 and 2 were 8, 11 and 14, respectively, and the annual thromboembolism event rates were 0.40% (95%CI 0.20%-0.81%), 0.39% (95%CI 0.22%-0.71%) and 1.34% (95%CI 0.80%-2.27%), respectively. The risk of thromboembolism of CHA2DS2-VASc score 2 group (HR=3.53, 95%CI 1.48-8.44; P=0.005), especially female patients aged 65-74 years in CHA2DS2-VASc score 2 group (HR=2.67, 95%CI 1.63-4.38; P<0.000) was significantly higher than that in patients of CHA2DS2-VASc score 0 group. Conclusion: Low-Risk Atrial Fibrillation patients with CHA2DS2-VASc score 2, especially female patients aged 65-74 years old with CHA2DS2-VASc score 2 are at higher risk of thromboembolism in low-risk AF patients. For such patients, intensified oral anticoagulant therapy might be helpful to reduce the risk of thrombolism.

Risk factors for recurrent hospitalizations of patients with atrial fibrillation / 中华心血管病杂志

Objective: To determine the predictors of recurrent hospitalizations among atrial fibrillation (AF) patients. Methods: We analyzed data from the Chinese Atrial Fibrillation Registry (CAFR), a prospective cohort study involving non-valvular atrial fibrillation (NVAF) patients from Augest 2011 to December 2017. A total of 5 349 NVAF patients with a minimum of 48 months follow-up were included for analysis. Data including patient demographics, complications, medical and ablation history were collected. The maximum number of all-cause hospitalizations within one-year for each patient served as the primary endpoint. Patients hospitalized less than twice within one-year were defined as non-recurrent hospitalizations group, those hospitalized at least twice within one-year were definned as recurrent hospitalizations group. Logistic regression model was used to identify associated risk factors for recurrent hospitalizations. Results: Of 5 349 NVAF patients, those hospitalized for 0, 1, 2, 3, 4 and at least 5 times within one-year was 2 703 (50.5%), 1 776 (33.2%), 642 (12.0%), 161(3.0), 52 (1.0%), 15 (0.3%), respectively. Eight hundred and seventy (16.3%) patients were included in recurrent hospitalizations group, 4 479 (83.7%) patients were included in non-recurrent hospitalizations group. Compare with non-recurrent hospitalizations group, patients in recurrent hospitalizations group was more likely to be older and female, more frequently had a history of hypertension, heart failure, coronary heart disesase, ischaemic stroke/transient ischaemic attack, diabetes mellitus, peptic ulcer, a AF duration for more than 1 year, medication including drugs for ventricular rate control, statin, angiotensin-converting enzyme inhibitors (ACEI)/angiotensin receptor blocker (ARB) and higher CHA(2)DS(2)-VASc scores (P<0.05), but less frequently had higher education, a history of drinking, smoking and ablation (P<0.05). Multivariable analysis showed that age 50-64 (OR=1.47, 95%CI 1.20-1.80), age≥65 (OR=1.89, 95%CI 1.50-2.38), female (OR=1.21, 95%CI 1.01-1.46), hypertension history (OR=1.42, 95%CI 1.16-1.74), heart failure history (OR=1.73, 95%CI 1.37-2.18), coronary heart disease history (OR=1.63, 95%CI 1.31-2.03), peptic ulcer history (OR=2.00, 95%CI 1.18-3.39) were independent risk factors for recurrent hospitalizations, while higher education (college or above) (OR=0.82, 95%CI 0.69-0.99) was the protective factor for recurrent hospitalizations. Conclusions: Nearly 1 in 6 of AF patients were admitted to hospital more than once within one year in this NVAF cohort. Age≥50, female, hypertension history, heart failure history, coronary heart disease history, peptic ulcer history are associated with an increased risk of recurrent hospitalizations.