The association between relevant comorbidities and dementia in patients with atrial fibrillation.

Risk of dementia is increased in patients with atrial fibrillation (AF). We aimed to study associations between relevant comorbidities and prevalent as well as incident dementia in AF patients. Study population included all adults (n = 12,283) ≥ 45 years diagnosed with AF at 75 primary care centers in Sweden 2001-2007. Logistic regression was used to calculate odds ratios (OR) with 95% confidence intervals (95% CI) for associations between comorbidities and prevalent dementia. In a subsample (n = 12,096), (excluding patients with dementia diagnosed before AF onset), Cox regression was used to estimate hazard ratios (HR) with 95% CIs for association between comorbidities, and incident dementia, after adjustment for age, socioeconomic factors and anticoagulant treatment. Totally 937 patients (7.6%), 388 men (5.8%) and 549 women (9.7%), were diagnosed with dementia. After adjustments, prevalent dementia was more common in (ORs, 95% CI) men with congestive heart failure (CHF), stroke, and depression; in women with CHF and depression, and among women > 75 years with stroke, but less common in women with hypertension. During a 5.6-year follow-up (standard deviation 2.5), 750 patients (6.2%; 322 men, 4.9%, and 428 women, 7.8%) were diagnosed with incident dementia. An increased risk of incident dementia was found among men with diabetes and depression; a decreased risk among men and women with CHF, and among women with hypertension, myocardial infarction cerebrovascular diseases. The findings regarding incident dementia need to be interpreted with great caution, as they may have been subject to survival bias.