Women With Atrial Fibrillation Have Higher Risk of Developing Dementia

Women with atrial fibrillation (AF) are more likely to experience mild cognitive impairment (MCI) and develop dementia, compared with women without AF or men with or without AF, according to study findings published in the journal Alzheimer’s & Dementia.

Researchers at Emory University in Atlanta, Georgia collected data from the National Institutes of Health (NIH)-sponsored National Alzheimer’s Coordinating Center (NACC) database from 1999 until March of 2021 on 43,630 individuals to assess cognitive and functional changes in people with vs without AF. They also investigated if sex differences affected the relationship between AF and Alzheimer disease and related dementias (ADRD).

Cognitive function was assessed using 9 neuropsychological tests, including: the Boston Naming Test (BOSTON), Trail Making Test (TRAILB), Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), Clinical Dementia Rating Scale (CDRSUM), Digit Span Forward (DIGIF), Digit Span Backward (DIGIB), and 2 memory tests for verbal episodic and semantic memory (MEMUNITS and ANIMALS).

Of the 43,640 individuals, 39,037 people (58.6% women) lived without AF, while 4,593 people (45.5% women) had AF at baseline. Around 81% of the AF group consisted of White individuals, 8% Black individuals, and 11% other ethnicities with an average age of 78.5 years.

The median follow-up time was around 4 years. Of the 13,683 individuals who survived to the end of the study, 4,066 (30%) demonstrated worsening cognitive impairment and 2,895 (21%) developed dementia with 2,434 (18%) cases involving ADRD.

Compared with women without AF, women with AF exhibited a higher likelihood of developing dementia (odds ratio [OR], 3.00; 95% CI, 1.22-7.37; P =.017) or MCI (OR, 3.43; 95% CI, 1.55-7.55; P =.002). The presence of AF increased the odds of developing MCI and dementia more among women than men (OR, 3.43 vs 1.73 and OR, 3.00 vs 2.60, respectively).

Similarly, women with AF demonstrated increased risk for disease progression from normal cognitive baselines to MCI (hazard ratio [HR], 1.26; 95% CI, 1.06-1.50) or from MCI to vascular dementia (HR, 3.27; 95% CI, 1.89-5.65) than men with AF or men and women without AF.

The researchers speculated about possible reasons contributing to the sex differences in this study. Compared with men with AF, women with AF are older, have more comorbidities, are less likely to receive oral anticoagulation for stroke prevention, and are at higher risk for stroke, heart failure, and death due to AF.

“Our findings imply that women with AF may be at higher risk of MCI and dementia with potentially more rapid disease progression from normal cognition to MCI or dementia than women without AF or men with and without AF,” the researchers concluded. “Establishing ways to identify those patients with AF at highest risk of cognitive decline and stroke will inform future interventions to prevent or slow AF-associated MCI and ADRD,” they added.

Study limitations included the small sample size of individuals with AF and lack of access to cardiac clinical data regarding time to stroke after AF diagnosis, type of stroke, duration and type of AF, and type of treatments for AF and adherence to them. Generalizability may have been affected due to lack of diversity among the NACC volunteers in terms of higher educational levels and better health status, compared with the general population.