How is New-Onset Atrial Fibrillation in Black Patients Connected to Resting Heart Rate?

Resting heart rate (RHR), as a known measure of cardiovascular fitness, and its association with atrial fibrillation (AF), has been widely studied in White patient populations. However, research about the risk of AF and its connection to RHR is lacking in Black patient populations, in comparison.

A recent study, published in JAMA Network Open, examined this connection by evaluating “the association between RHR and incident AF in a large community-based sample of Black adults, independently of established risk factors.”

Vidhushei Yogeswaran, MD, of the University of Washington, conducted the investigation using data from the Jackson Heart Study, which was a prospective community-based cohort study in Jackson, Mississippi. In the Jackson Heart Study, eligible participants did not present with AF and were monitored for new-onset AF from 2000-2016. The analysis of this study data was conducted from August 1, 2023, to December 11, 2023.

To assess RHR, the researchers used resting 12-lead electrocardiograms. Assessments were performed during follow-up appointments, with examination one occurring from 2000-2004 and examination three occurring from 2009-2013.

The investigators also used electrocardiograms to identify AF, in addition to hospitalization discharge diagnosis codes and Medicare claims diagnosis codes. To assess the correlation between the baseline RHR measured at examination one and the onset of AF, while adjusting for risk factors, they used Cox regression.

The study examined results from 4,965 Black patients. Of them, 37% were male, and the mean age was 55 years. At baseline, the mean RHR was 65 beats per minute (bpm). At the median follow-up point of 14 years, there were 458 cases of newly-onset AF. The incident rate for newly-onset AF was measured at 7.5 per 1,000 person-years (95% CI, 6.8-8.2 incidents per 1,000 person-years).

According to the study findings, “each 10-bpm higher RHR was associated with a 9% higher risk of incident AF after adjustment for AF risk factors (hazard ratio, 1.09; 95% CI, 1.00 – 1.19).”

The researchers also conducted a sensitivity analysis that “excluded individuals with prior heart failure, prior myocardial infarction, and antiarrhythmic medication use at baseline.”

The study results determined that there was little evidence to suggest that age, sex, body mass index, hypertension, or physical activity level influenced RHR association with AF.

Ultimately, the study demonstrated that an elevated RHR at baseline measurement was associated with an increased risk of newly-onset AF, which the researchers stated was “consistent with findings from previous studies of European ancestry populations. The investigators also wrote that “future research should focus on determining whether RHR can be used to screen patients at high risk of AF.”

Source: JAMA Network Open