Fibrilação atrial e demência: resultados do São Paulo ageing & health study

BACKGROUND: Atrial fibrillation (AF) is a controversial risk factor for dementia. OBJECTIVE: The objective of this study was to assess the association between AF and dementia in the "Sao Paulo Ageing & Health" (SPAH) study participants. METHODS: SPAH is a cross-sectional, population-based study of elderly people living in a deprived neighborhood in Sao Paulo, Brazil. Dementia diagnosis was performed according to the 10/66 study group protocol based on Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) criteria. Diagnosis of AF was made using a 12-lead electrocardiogram (ECG) recording, which was assessed by two cardiologists. Data on demographics and cardiovascular risk factors were also obtained. RESULTS: Dementia was diagnosed in 66 (4.3%) and AF in 36 (2.4%) of 1,524 participants with a valid ECG. The crude odds ratio (OR) for dementia in participants with AF was 2.8 (95% confidence interval [CI]: 1.0-8.1; p=0.06) compared with individuals without AF. When analyzing data according to sex, a positive relationship was found in women (OR 4.2; 95% CI: 1.24-15.1; p=0.03). After age-adjustment, however, this association was no longer significant (OR 2.2; 95% CI: 0.6-8.9; p=0.26). CONCLUSION: There was no independent association between AF and dementia in this sample. The prevalence of AF may be low in this population owing to premature cardiovascular death.