Atrial fibrillation is independently associated with senile, vascular, and Alzheimer's dementia.

BACKGROUND

The aging population has resulted in more patients living with cardiovascular disease, such as atrial fibrillation (AF). Recent focus has been placed on understanding the long-term consequences of chronic cardiovascular disease, such as a potential increased risk of dementia.

OBJECTIVE

This study sought to determine whether there is an association between AF and dementia and whether their coexistence is an independent marker of risk.

METHODS

A total of 37,025 consecutive patients from the large ongoing prospective Intermountain Heart Collaborative Study database were evaluated and followed up for a mean of 5 years for the development of AF and dementia. Dementia was sub-typed into vascular (VD), senile (SD), Alzheimer's (AD), and nonspecified (ND).

RESULTS

Of the 37,025 patients with a mean age of 60.6 +/- 17.9 years, 10,161 (27%) developed AF and 1,535 (4.1%) developed dementia (179 VD, 321 SD, 347 AD, 688 ND) during the 5-year follow-up. Patients with dementia were older and had higher rates of hypertension, coronary artery disease, renal failure, heart failure, and prior strokes. In age-based analysis, AF independently was significantly associated with all dementia types. The highest risk was in the younger group (<70). After dementia diagnosis, the presence of AF was associated with a marked increased risk of mortality (VD: hazard ratio [HR] = 1.38, P = .01; SD: HR = 1.41, P = .001; AD: HR = 1.45; ND: HR = 1.38, P <.0001).

CONCLUSION

AF was independently associated with all forms of dementia. Although dementia is strongly associated with aging, the highest risk of AD was in the younger group, in support of the observed association. The presence of AF also identified dementia patients at high risk of death.