Impact of cognitive impairment on clinical outcomes in elderly patients with atrial fibrillation: ANAFIE Registry

BACKGROUND: This subcohort study of All Nippon AF In the Elderly (ANAFIE) Registry based on 33 275 elderly patients (aged ≥75 years) with non-valvular atrial fibrillation (NVAF) investigated the relationship between cognitive function and 2-year clinical outcomes. METHODS: A total of 2963 (mean age, 81.4 years) patients participated in this subcohort study and were classified as having normal cognition (Mini-Mental State Examination (MMSE) score ≥24/30) or cognitive impairment (score ≤23/30) at baseline. Patients with a decrease of >2 points after 24 months were classified as having cognitive decline. RESULTS: At baseline, 586 (19.8%) patients had cognitive impairment. These patients tended to be older and had poorer general conditions than patients with normal cognition. The 2-year probability of stroke/systemic embolic events (SEEs), major bleeding and intracranial haemorrhage was numerically higher; those of cardiovascular death, all-cause death and net clinical outcome (composite of stroke/SEE, major bleeding and all-cause death) were significantly higher (all p<0.001) in patients with cognitive impairment versus normal cognition. In multivariate analysis, the risks of cardiovascular death (p=0.021), all-cause death (p<0.001) and net clinical outcome (p<0.001) were higher in patients with cognitive impairment versus those with normal cognition. After 24 months, 642 of 1915 (33.5%) patients with repeated MMSE determination had cognitive decline. Educational background <9 years, older age and concomitant cerebrovascular disorders were significant risk factors of cognitive decline at the 2-year follow-up. CONCLUSIONS: Elderly patients with NVAF with cognitive impairment have a higher mortality risk than those with normal cognition. Several significant risk factors of cognitive decline were identified at 2-year follow-up. TRIAL REGISTRATION NUMBER: UMIN000024006 (http://www.umin.ac.jp/).