Venous Thromboembolism and Critical Limb Events in Patients with Atrial Fibrillation: A Nationwide Population-Based Cohort Study

Little is known about whether venous thromboembolism (VTE) causes worse critical limb events in populations with atrial fibrillation (AF). A retrospective cohort study using claims data from Taiwan's National Health Insurance program between 2001 and 2013 compared AF patients with or without VTE. Outcomes were percutaneous transluminal angioplasty (PTA), amputation, systemic thromboembolism, all-cause mortality, cardiovascular death, ischemic stroke, and acute myocardial infarction. Patients (n = 316,817) with newly diagnosed AF were analyzed; of those, 2514 (0.79%) had VTE history. After inverse probability of treatment weighting, a history of VTE was significantly associated with higher risks of PTA (3.3 vs 2.2%; subdistribution hazard ratio [SHR] 1.47; 95% confidence interval [CI] 1.17-1.84); above knee amputation (0.7 vs 0.3%; HR 2.15; 95% CI 1.10-4.21); systemic thromboembolism (5.8 vs 3.9%; SHR 1.48; 95% CI 1.21-1.80); all-cause mortality (53 vs 46.4%; HR 1.20, 95% CI 1.12-1.29); and cardiovascular death (34.8 vs 29.4%; HR 1.25, 95% CI 1.14-1.36). In conclusion, VTE might increase the risk of critical lower limb events (PTA and above-knee amputation), systemic thromboembolism, and mortality in the AF population. However, current data cannot confirm a causal relationship between VTE and clinical outcomes in this population.