Effect of anti-coagulation in elderly patients with atrial fibrillation

Abstract

Background: Atrial fibrillation has been shown to associate with greater cognitive decline and increased dementia risk independent of ischaemic stroke. Anti-coagulation was associated with a lower risk of ischemic stroke and positive net clinical benefit in elderly patients in Asian populations. We hypothesise that elderly patients (>75 years old) with atrial fibrillation on oral anti-coagulants have lower incidence of dementia compared with patients on anti-platelet agents or no anti-thrombotic treatment. Method: A retrospective study of 747 patients, male 37%, mean age 84.29 ± 5.99 years old with mean follow up of 13.54 ± 3.38 years. 94 % hypertension, 40% diabetes mellitus, 38% ischaemic heart disease, 33% heart failure, 39% previous stroke, mean CHA2DS2-VASc score of 5.23 ± 1.59. 27% patients on oral anti-coagulants, 64% anti-platelet agent and 9% not on any anti-thrombotic medication. Results: 265 patients were diagnosed with dementia, 17 patients were on oral anti-coagulants, 222 patients were on anti-platelet agent. Oral anti-coagulants were associated with lower incidence of dementia compared with anti-platelet agents (p < 0.0001). 26 patients developed dementia were not on any anti-thrombotic agent. 261 patients were readmitted with stroke (2.58%/100 patient year) 182 patients were on antiplatelet agent while 12 were on anti-coagulant (P < 0.0001). Conclusions: Oral anti-coagulants were associated with lower incidence of dementia and stroke compared with anti-platelet agents in elderly patients with atrial fibrillation.