Megan Brooks

November 13, 2023

TOPLINE:
Adults with atrial fibrillation (AF) are at increased risk for dementia, especially when AF occurs before age 65 years, new research shows. Investigators note the findings highlight the importance of monitoring cognitive function in adults with AF.

METHODOLOGY:
This prospective, population-based cohort study leveraged data from 433,746 UK Biobank participants (55% women), including 30,601 with AF, who were followed for a median of 12.6 years

Incident cases of dementia were determined through linkage from multiple databases.

Cox proportional hazards models and propensity score matching were used to estimate the association between age at onset of AF and incident dementia.

TAKEAWAY:
During follow-up, new-onset dementia occurred in 5898 participants (2546 with Alzheimer’s disease [AD] and 1211 with vascular dementia [VD]), of which, 1031 had AF (350 with AD; 320 with VD).

Compared with participants without AF, those with AF had a 42% higher risk for all-cause dementia (adjusted hazard ratio [aHR], 1.42; P < .001) and more than double the risk for VD (aHR, 2.06; P < .001), but no significantly higher risk for AD.

Younger age at AF onset was associated with higher risks for all-cause dementia, AD and VD, with aHRs per 10-year decrease of 1.23, 1.27, and 1.35, respectively (P < .001 for all).

After propensity score matching, AF onset before age 65 years had the highest risk for all-cause dementia (aHR, 1.82; P < .001), followed by AF onset at age 65-74 years (aHR, 1.47; P < .001). Similar results were seen in AD and VD.

IN PRACTICE:
“The findings indicate that careful monitoring of cognitive function for patients with a younger AF onset age, particularly those diagnosed with AF before age 65 years, is important to attenuate the risk of subsequent dementia,” the authors write.

SOURCE:
The study, with first author Wenya Zhang, BS, with Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China, was published online November 8, 2023 in JAMA Network Open.

LIMITATIONS:
Because the study was observational, a cause-effect relationship cannot be established. Despite the adjustment for many underlying confounders, residual unidentified confounders may still exist. The vast majority of participants were White. The analyses did not consider the potential impact of effective treatment of AF on dementia risk.

DISCLOSURES:
The study had no commercial funding. The authors have declared no conflicts of interest.