To determine the association of SCT with AF, a team of researchers, including Dr. George Howard and Dr. Marguerite “Ryan” Irvin from UAB’s School of Public Health, collaborated to investigate.

Among African-American participants in the REasons for Geographic and Racial Differences in Stroke (REGARDS) Study UAB researchers assessed the association of SCT (by ECG or medical history) with prevalent AF using logistic regression adjusting for age, sex, income, education, history of stroke, myocardial infarction, diabetes, hypertension, and chronic kidney disease. A second evaluation was performed a mean of 9.2 years later among available participants, and the same model was used to test the association of SCT with incident AF.

In 10,409 participants with baseline ECG data and genotyping, 778 had SCT and 811 had prevalent AF. After adjusting for age, sex, education and income, SCT was associated with AF, OR 1.32 (95 percent CI 1.03-1.70). The association with incident AF assessed at the second in-home visit with the same adjustments was similar; OR 1.25 (95 percent CI 0.77-2.03).

SCT was associated with a higher prevalence of AF and a non-significantly higher incident AF over a 9.2 year period independent of AF risk factors. SCT remained associated with prevalent AF after adjusting for potential factors on the causal pathway such as hypertension and chronic kidney disease suggesting alternate mechanisms for the increased risk.