Combination of Oral Anticoagulant with Antiplatelet and All-cause Mortality in Elderly Patients with Atrial Fibrillation and Ischemic Heart Disease

Aim: Clinicians are often face the dilemma of choosing more appropriate antithrombotic regimen, since there is no evidence regarding the role of combination of Oral Anticoagulant (OAC) and antiplatelet which played in elderly patients with Atrial Fibrillation (AF) and Ischemic Heart Disease (IHD). We therefore aimed to investigate the effect of combination of OAC and antiplatelet on all-cause mortality in elderly patients with AF and IHD.

Study Design: This is a retrospective analytical study.

Place and Duration of the Study: The study was conducted in Chinese PLA General Hospital, Beijing, China. Selected patients' data available for the period between 2008 and 2014 were included in this study.

Methods: A total of 669 elderly patients with AF and IHD between 2008 and 2014 were included (mean age, 80.8 years; 67.5% men). The endpoint was all-cause mortality. Risk of all-cause death was examined with Kaplan-Meier analysis and adjusted Cox regression models.

Results: During a median follow-up of 1.3 years, the mortality rate was 74.3% for patients with antiplatelets, 58.6% for OAC and 42.9% for combination of both, respectively. OAC and /or antiplatelet use were associated with risk of mortality (chi-square=11.03, log rank p = 0.004) using unadjusted Kaplan-Meier analysis. In overall cohort, the adjusted hazard ratios for mortality for combination of OAC and antiplatelet was 0.41 (95% CI 0.19-0.87, p = 0.019) as compared to antiplatelet use, 0.80 (95% CI 0.39-1.64, p = 0.541) as compared to OAC use. In subgroup age ≥ 75 years, the adjusted hazard ratios for mortality were 0.40 (95% CI 0.16-1.02, p = 0.054) for combination of OAC and antiplatelet as compared to antiplatelet use, 0.79 (95% CI 0.31-1.96, p = 0.605) for combination of OAC and antiplatelet as compared to OAC use, and compared to antiplatelet use, the adjusted hazard ratio for mortality were 0.51 (95% CI 0.32-0.81, p = 0.005) for OAC use.

Conclusions: Combination of OAC with antiplatelet is associated with reduced all-cause mortality and OAC is better on outcome as compared to antiplatelet agents, but OAC plus antiplatelet is not superior to OAC in elderly patients with AF and IHD and in subgroup aged ≥ 75 years.