Cardiac Disease, Atrial Fibrillation, and Cognitive Impairment Risk

There is little doubt that the world is growing older. Many countries are no longer producing enough new live births to replace those who die. If we add the impact of an increasingly obese population in developed nations, it is easy to predict that the prevalence of cardiac disease will continue to increase unless there are major changes in health-related behaviors and hygienic practices. Neither appears likely: numerous articles describe a lack of adherence to drug, dietary, and exercise regimens, and continued smoking.

Now a new study has explored the association between atrial fibrillation (AF) and incident dementia. Santangeli and colleagues¹ analyzed 8 studies that included 77,668 patients (mean age, 61 to 84 years). All 8 studies were of prospective design. At baseline, all subjects had normal cognition; 11,700 (15%) had AF. After a mean follow-up of 7.7 years, dementia had developed in 6.5% (4773 of 73,321 subjects).

The analysis demonstrated that AF was independently associated with an increased risk of dementia (hazard ratio = 1.42; 95% confidence interval, 1.17 - 1.72; P <  .001). The data were adjusted for age, gender, hypertension, diabetes, coronary artery disease, and previous stroke.

At the very least, results of this study suggest that all patients with AF should be screened periodically for cognitive impairment. While there is currently no magic pill to forestall dementia, major research studies are currently under way. In addition, some publications have demonstrated that while cardiovascular disease risk factors may have an impact on cognitive decline, exercise can have a positive impact on the degree of risk.²

References
1. Santangeli P, Di Biase L, Bai R, et al. Atrial fibrillation and the risk of incident dementia: a meta-analysis. J Heart Rhythm. 2012;9:1761-1768.
2. Nash DT, Fillit H. Cardiovascular disease risk factors and cognitive impairment. Am J Cardiol. 2006;97:1262-1265.