According to findings published in the International Journal of Cardiology, researchers have identified a possible racial predisposition to atrial fibrillation (AF) among individuals with a combination of albuminuria and electrocardiographic left atrial abnormality (ECG-LAA).
Recruitment for the long-term study took place between 2000 and 2002. The study examined 6670 participants aged 45 to 84 years. Participants were enrolled at 6 sites in the United States. Participants did not have clinical cardiovascular disease when the study began.
Participants were assessed for ECG-LAA, which the authors defined as P-wave terminal force in V1 greater than 5000 μV × ms. They were also assessed for albuminuria, which the authors defined as a urine albumin-creatinine ratio (UACR) of 30 mg/g or greater.
Over the course of the study, the investigators tracked incident AF using a combination of follow-up study ECGs and telephone interviews to identify hospital admissions and medical diagnoses. In addition, the researchers used hospital discharge records of diagnosis of AF, as well as AF-related inpatient, outpatient, and physician claims data for participants enrolled in fee-for-service Medicare.
All participants were followed from recruitment until 2015.
The data were analyzed using the Cox proportional hazard model to assess multiple associations with AF. Patients were stratified into the following groups:
- Patients without albuminuria and ECG-LAA (reference)
- Patients with albuminuria only (isolated albuminuria)
- Patients with ECG-LAA only (isolated ECG-LAA)
- Patients with albuminuria and ECG-LAA
Additional data modeling was performed to adjust for age, sex, race, socioeconomic factors, and certain health indicators.
At baseline, the researchers found that ECG-LAA was higher among patients who had albuminuria than in those without albuminuria (12.9% vs 6.2%, respectively; P <.01). The prevalence of ECG-LAA was 11.4% (n=212) among Black participants vs 5.2% (n=132) among White participants. The prevalence of albuminuria was 11.5% among Black participants vs 5.8% among White participants.
The researchers recorded 979 cases of AF during the study. Rates of AF were highest among participants with concomitant albuminuria and ECG-LAA (40.1 per 1000 person-years). Lower rates were reported in participants who displayed albuminuria alone (23.3 per 1000 person-years) or ECG-LAA alone (19.9 per 1000 person-years).
Comparative analysis by race showed a 4-fold greater AF risk for Black participants who had both albuminuria and ECG-LAA (hazard ratio [HR], 4.37; 95% CI, 2.38-8.01). There was no statistically significant risk increase in White participants (HR, 0.60; 95% CI, 0.19-1.92).
Study limitations include a lack of data on social determinants of health among participants. The study did not address longitudinal changes and their impact on health outcomes.
“Concomitant presence of ECG-LAA and albuminuria confers a higher risk for AF compared to either one in isolation with a stronger association in Black [patient]s than White [patient]s,” the study authors wrote. They also urged further study on the matter, noting the implications on other health outcomes for Black individuals.
Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Ahmad MI, Chen LY, Singh S, Luqman-Arafath TK, Kamel H, Soliman EZ. Interrelations between albuminuria, electrocardiographic left atrial abnormality, and incident atrial fibrillation in the Multi-Ethnic Study of Atherosclerosis (MESA) cohort. International Journal of Cardiology. Published online April 23, 2023. doi:10.1016/j.ijcard.2023.04.036