Chronic obstructive pulmonary disease and Vitamin K antagonism: A cohort study of 1-year all-cause mortality and risk of hospitalization due to a severe exacerbation of COPD

<bold>Background</bold> Through vitamin-K-dependent activation of matrix-GLA-protein, Vitamin K has been hypothesized as being lung protective; the mechanism is unknown. COPD-patients treated with Vitamin-K antagonists (VKAs) may lose this protection, thereby increasing their risk of an acute exacerbation of COPD (AE-COPD) and death. We tested this hypothesis in a cohort of VKA- or direct oral anticoagulant(DOAC)-treated COPD-patients with non-valvular atrial fibrillation or flutter. <bold>Objective</bold> To assess the 1-year risk of hospitalization due to an AE-COPD and all-cause mortality in our cohort. <bold>Methods</bold> A nationwide, observational, register-based cohort-study. A cox proportional hazard regression model was applied, adjusting for established confounders. Hazard ratios (HR) with 95% confidence intervals (CI) were reported. <bold>Results</bold> A total of 7.091 COPD-patients were included, of whom 3.455 received VKA-treatment (48.7%). A total of 1.955 patients reached the end-point, 820 in the VKA-treated group. The primary analysis showed an adjusted HR of 0.87, p=0.024, CI:(0.78–0.98) in favor of VKA-treatment. Complete-case analysis found an adjusted HR of 0.88, p=0.079, CI:(0.76–1.01). Our IPTW-analysis found an HR of 0.85, p=0.070, CI:(0.72–1.01). <bold>Interpretation</bold> VKA treatment was associated with a reduction in AE-COPD hospitalization and mortality compared to DOAC. <fig><object-id>erj;66/suppl_69/PA3678/F1</object-id><object-id>F1</object-id><object-id>F1</object-id><graphic></graphic></fig>