Oral anticoagulant therapy and outcome in patients with stroke. A retrospective nation-wide cohort study in Austria 2012-2017

Purpose: Patients with stroke are at high risk of recurrence of vascular events. Non-vitamin K oral anticoagulant (NOAC) and vitamin K antagonists (VKA) are used as secondary prophylaxis. The aim of this study was to evaluate the utilization of NOAC and VKA, and their impact on re-stroke or death in Austria.

Methods: We analyzed retrospective data between 2012 and 2017 from medical services covered by the health insurance funds, which provides health care for all residents in Austria. Patients without anticoagulant medication 3 months preceding the index event were eligible.

Results: 76 354 patients were discharged with a hospital diagnosis of stroke. From these, 16 436 patients with a median age of 78 years received VKA or NOAC. After adjustment, the recurrence of stroke was less frequent in patients with NOAC compared to those with VKA (HR 0.87; 95%CI 0.77-0.97). However, there was no difference in mortality rate after adjustment for age, sex, and co-morbidities for patients with NOAC (HR 1.0; 95%CI 0.92-1.08). Diabetes (HR 1.25, 95%CI 1.08-1.45; HR 1.25, 95% CI 1.13-1.38) and cardiovascular disease (HR 1.43, 95%CI 1.24-1.65; HR 1.27, 95%CI 1.16-1.39) were significantly associated with re-stroke or death. Younger age (p = 0.0028; HR 0.99, 95%CI 0.99-0.99) was significantly associated with re-stroke, and advanced age (p < 0.0001; HR 1.09, 95%CI 1.08-1.09) with death.

Conclusion: NOAC prescription is related with a reduced risk of re-stroke but increased mortality compared to patients with VKA. The event risk is associated with diabetes, cardiovascular disease and age.