Racial Differences in Left Atrial Size: Results from the Coronary Artery Risk Development in Young Adults (CARDIA) Study

• Published in: PloS one 2016-03, Vol.11 (3), p.e0151559-e0151559
• Main Authors: Dewland, Thomas A, Bibbins-Domingo, Kirsten, Lin, Feng, Vittinghoff, Eric, Foster, Elyse, Ogunyankin, Kofo O, Lima, Joao A, Jacobs, David R, Hu, Donglei, Burchard, Esteban G, Marcus, Gregory M
• Format: Article
• Language: English
• Subjects: Adjustment; Adolescent; Adult; Adults; African Americans; Alcohol; Alcohol use; Atrial Fibrillation - etiology; Biology and Life Sciences; Black People; Cardiac arrhythmia; Cardiology; Cardiovascular disease; Comparative analysis; Coronary artery; Coronary heart disease; Coronary vessels; Demographic aspects; Demographics; Demography; Echocardiography; Epidemiology; Family medical history; Female; Fibrillation; Genomes; Health aspects; Health risk assessment; Heart; Heart Atria - anatomy & histology; Humans; Hypertension; Laboratories; Male; Medicine; Medicine and Health Sciences; Older people; Organ Size - physiology; People and Places; Physiological aspects; Race; Racial differences; Regression analysis; Regression models; Research and Analysis Methods; Risk factors; Set theory; Stroke; Veins & arteries; White People; Whites; Young Adult; Young adults; Youth
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0151559

Whites have an increased risk of atrial fibrillation (AF) compared to Blacks. The mechanism underlying this association is unknown. Left atrial (LA) size is an important AF risk factor, and studies in older adults suggest Whites have larger LA diameters. However, because AF itself causes LA dilation, LA size differences may be due to greater subclinical AF among older Whites. We therefore assessed for racial differences in LA size among young adults at low AF risk. The Coronary Artery Risk Development in Young Adults (CARDIA) study enrolled White and Black participants between 18 and 30 years of age. LA diameter was measured in a subset of participants using echocardiography at Year 5 (n = 4,201) and Year 25 (n = 3,373) of follow up. LA volume was also assessed at Year 5 (n = 2,489). Multivariate linear regression models were used to determine the adjusted association between race and LA size. In unadjusted analyses, mean LA diameter was significantly larger among Blacks compared to Whites both at Year 5 (35.5 ± 4.8 mm versus 35.1 ± 4.5 mm, p = 0.01) and Year 25 (37.4 ± 5.1 mm versus 36.8 ± 4.9 mm, p = 0.002). After adjusting for demographics, comorbidities, and echocardiographic parameters, Whites demonstrated an increased LA diameter (0.7 mm larger at Year 5, 95% CI 0.3-1.1, p