Silent atrial fibrillation correlates with cognitive performance in older persons

Objective: Atrial fibrillation (AF) coexists with dementia in older population. AF often remains undiagnosed due to the occurrence in an asymptomatic form - silent AF (SAF). The aim of the study is to evaluate the relationships between cognitive performance and AF both symptomatic and silent in a representative Polish older population. Design and method: The study was conducted as a sub-analysis of the NOMED-AF, a cross-sectional observational study aiming to evaluate the epidemiology of AF in a representative, community-dwelling Polish sample of adults aged 65 years or more. Mini-Mental State Examination (MMSE) was used to assess cognitive disorders. Each study participant, regardless of AF history, was equipped with a continuous electrocardiogram wearable recording system and encouraged to wear it for up to 30 days. Results: A sample of 2203 participants from the NOMED-AF study was enrolled in the analyses (mean age 77.1 years, 48.4% female); 491 (22.3%) were diagnosed with AF (41.3% of them with SAF). The mean number of points obtained by the respondents in the MMSE was 25.8±0.1 and was significantly lower in patients with AF (25.2±0.22 vs 26±0.11) This difference between patients with arrhythmia and those without AF was present in the subgroup of subjects aged 65-79 years (26.8±0.21 vs 27.4±0.08) and absent in the older subgroup (23.6±0.36 vs 23.3±0.24) (Fig. 1a). There was a significant difference in the number of points obtained between patients with the symptomatic and silent forms of arrhythmia, with a lower score obtained in the latter group (25.8±0.26 vs 24.3±0.38), which was consistent in both age subgroups (Fig. 1b). Finally, in the multivariate logistic regression model, the impact of SAF (but not overall AF) on MMSE scores has been demonstrated. Conclusions: In the older population the presence of AF is associated with a lower MMSE score. As for the silent form of arrhythmia, this relationship is deeper and independent of other risk factors, what suggests the need for a particularly thorough assessment of cognitive disorders in patients with AF and, on the other hand, active search for asymptomatic AF in the group of patients with dementia.