Abstract 15046: Lower Occurrence of Atrial Fibrillation on 48-Hour Holter in African-Americans Than Whites
Introduction: Studies of atrial fibrillation (AF) based on 12-lead ECGs, hospital claims, and medical records have found a lower AF prevalence, but counterintuitively an adverse cardiovascular disease risk profile in African-Americans (AAs) than Whites.
Hypothesis: Based on equal duration of ambulatory ECG monitoring (aECG), AF prevalence will be comparable in AAs and Whites.
Methods: We performed 48-hour aECG in a biracial sample of 1193 participants (mean age 74 years (SE 0.18), 62% AA, 64% female) at two of the Atherosclerosis Risk in Communities (ARIC) centers (Jackson, MS; Forsyth, NC). We administered questionnaires during a standardized 1-hour clinic visit and placed aECG monitor (SEER Light Extend Compact Digital Holter Recorder; GE, Milwaukee, WI), which was worn for 48 hours during usual activities. Reading, quality control, and analysis of recordings were performed by a central ECG lab (EPICARE, Wake Forest School of Medicine, Winston Salem, NC). An AF event was defined as any duration of AF (>0%), and persistent AF and paroxysmal AF were defined as 99-100% and <10% AF duration, respectively. We used logistic regression to estimate odds ratios and 95% CIs for occurrence of AF in AAs versus whites.
Results: African-Americans were more likely than Whites to have hypertension and diabetes, but not coronary heart disease. The prevalence of AF detected by aECG was lower in AAs than Whites (2.6% versus 5.8%, p<0.005); 18 participants (9 per race group) had previously undetected AF. Among those with AF detected by Holter, the prevalence of persistent AF was higher in Whites than AAs (73% versus 47%). Paroxysmal AF, however, was higher for AAs than whites (21% versus 8%). Symptoms with AF were similar in Whites and AAs (19% versus 16%). Prevalent AF on prior ECG, a prior hospitalization, or the aECG, was also lower in AAs than Whites (4.4% versus 10.9%, p<0.0001). The age-adjusted OR (95%CI) for AF on Holter in AAs versus Whites was 0.41 (0.26-0.64). For persistent AF, it was 0.29 (0.13-0.65).
Conclusion: Based on an equal duration aECG, AF was less prevalent and more often paroxysmal in AA than White older adults. Although overall detection of new AF cases with aECG was low, future studies should consider longer-term monitoring to characterize AF in population subgroups.
Author Disclosures: L.R. Loehr: None. E.Z. Soliman: None. A.K. Poon: None. E.A. Whitsel: None. A. Alonso: None. L.Y. Chen: None. L. Wruck: None. T.H. Mosley: None. L. Wagenknecht: None. G. Heiss: None.
- © 2016 by American Heart Association, Inc.