Benefits and harms of oral anticoagulants for atrial fibrillation in nursing home residents with advanced dementia

Background Approximately 20% of older persons with dementia have atrial fibrillation (AF). Nearly all have stroke risks that exceed the guideline-recommended threshold for anticoagulation. Although individuals with dementia develop profound impairments and die from the disease, little evidence exists to guide anticoagulant discontinuation, and almost one-third of nursing home residents with advanced dementia and AF remain anticoagulated in the last 6 months of life. We aimed to quantify the benefits and harms of anticoagulation in this population. Methods Using Minimum Data Set and Medicare claims, we conducted a retrospective cohort study with 14,877 long-stay nursing home residents aged >= 66 between 2013 and 2018 who had advanced dementia and AF. We excluded individuals with venous thromboembolism and valvular heart disease. We measured anticoagulant exposure quarterly, using Medicare Part D claims. The primary outcome was all-cause mortality; secondary outcomes were ischemic stroke and serious bleeding. We performed survival analyses with multivariable adjustment and inverse probability of treatment (IPT) weighting. Results In the study sample, 72.0% were female, 82.7% were aged >= 80 years, and 13.5% were nonwhite. Mean CHA(2)DS(2)VASC score was 6.19 +/- 1.58. In multivariable survival analysis, anticoagulation was associated with decreased risk of death (HR 0.71, 95% CI 0.67-0.75) and increased bleeding risk (HR 1.15, 95% CI 1.02-1.29); the association with stroke risk was not significant (HR 1.08, 95% CI 0.80-1.46). Results were similar in models with IPT weighting. While >50% of patients in both groups died within a year, median weighted survival was 76 days longer for anticoagulated individuals. Conclusion Persons with advanced dementia and AF derive clinically modest life prolongation from anticoagulation, at the cost of elevated risk of bleeding. The relevance of this benefit is unclear in a group with high dementia-related mortality and for whom the primary goal is often comfort.