Atrial Fibrillation Tied to Higher Incidence of Dementia
Stroke patients who have atrial fibrillation are 2.4 times more likely to develop dementia
TUESDAY, March 8 (HealthDay News) -- Atrial fibrillation (AF) is associated with an increased incidence of dementia, and this association is strongest in patients with stroke, according to a meta-analysis published in the March 8 issue of Neurology.
Chun Shing Kwok, from the Norfolk and Norwich University Hospital in the United Kingdom, and colleagues carried out a meta-analysis of 14 prospective studies published before September 2010 to evaluate the risk of incident dementia in patients with AF. Pooled odds ratios for AF and dementia were calculated and heterogeneity assessed using I² in a total of 46,637 participants with an average age of 71.7 years.
In all the studies, the investigators found that AF was correlated with a significant increase in dementia incidence with substantial heterogeneity (odds ratio [OR], 2.0; I² = 75 percent). Seven studies focusing only on patients with stroke found a significant association with little heterogeneity (OR, 2.4; I² = 10 percent). The correlation was borderline significant with substantial heterogeneity in seven studies of broader populations (OR, 1.6; P = 0.05; I² = 87 percent). One study showed a significant association between AF and conversion of mild cognitive impairment to dementia (OR, 4.6).
"Subgroup analysis based on studies that focused solely on patients with stroke indicates that this overall increased risk of dementia in people with AF is primarily driven by the significant and consistent risk in patients with stroke, which contrasts sharply with the markedly heterogeneous estimates in studies based on broader populations," the authors write.