Comparative effectiveness and safety of direct oral anticoagulants versus warfarin in UK patients with atrial fibrillation and type 2 diabetes: a retrospective cohort study

Abstract

PURPOSE: To estimate the effectiveness and safety of direct oral anticoagulants (DOACs) compared with warfarin in AF patients with type 2 diabetes (T2DM). METHODS: A retrospective cohort study was designed, using the UK Clinical Practice Research Datalink (August 2011 - June 2018). Participants were 1-year naïve users of DOACs or warfarin, followed from the date of first prescription of an oral anticoagulant until the end of the study period, death, discontinuation of treatment, switching to another anticoagulant, or an outcome of interest, whichever came first. Cox regression analysis was performed to estimate the hazard ratio (HR) adjusted for potential confounders. RESULTS: A total of 8,555 patients were identified. No significant differences were found between DOACs and warfarin in the risk of stroke (adjusted HR 1.15; 95% CI 0.82 - 1.60), ischemic and unspecified stroke (adjusted HR 1.23; 95% CI 0.86 - 1.76) or haemorrhagic stroke (adjusted HR 0.75; 95% CI 0.30 - 1.85), and myocardial infarction (adjusted HR 1.39 ;95% CI 0.99 - 1.97). DOAC and warfarin users were comparable with respect to risk of major bleed (adjusted HR 0.83; 95% CI 0.68 - 1.03), intracranial bleeding (HR 0.66; 95% CI 0.34 - 1.30), gastrointestinal bleeding (HR 0.88; 95% CI 0.60 - 1.30), and bleeding on other clinically relevant sites (HR 0.89; 95% CI 0.60 - 1.31). In the subgroup analyses stratified by gender and diabetes severity, the risk for stroke and bleeding remained consistent. CONCLUSION: DOACs are effective and safe alternatives to warfarin for the prevention of stroke in AF patients with T2DM.