Brachial Flow-Mediated Dilation and Risk of Atrial Fibrillation in Older Adults: The Cardiovascular Health Study

Abstract

Background: Endothelial dysfunction is associated with common risk factors for AF and has been implicated in the pathophysiology of atrial fibrillation (AF) through a variety of mechanisms. We determined the prospective association of brachial flow-mediated dilation (FMD) with incident AF among older adults. Methods: We included 2027 Cardiovascular Health Study participants (mean age=78.3 years, male=39%, Black=17%) who underwent brachial FMD measurement at the 1997 to 1998 clinic visit. Incident AF was ascertained by study electrocardiograms, hospital dis-charge diagnosis coding and Medicare claims data. Cox regression models were used to examine the association between FMD and incident AF. Results: We identified 754 incident of AF cases (37%) over a median follow-up of 11.0 years. After adjusting for age, sex, race, height, weight, cardiovascular disease, cigarette smoking, hypertension, diabetes, kidney function, c-reactive protein, physical activity, alco-hol consumption, and statins, the risk of AF did not differ according to brachial FMD response (4th vs 1st quartile hazard ratio (HR)=1.01, 95% confidence interval (CI): 0.81, 1.26; per FMD unit increment HR=1.01, 95% CI: 0.97, 1.05). Conclusion: We found no relationship between brachial FMD and the risk of developing AF in this elderly cohort. Our findings suggest that the utility of brachial FMD as a risk marker for AF in older individuals is minimal. © 2021 Garg et al.