Racial Disparities in Awareness and Treatment of Atrial Fibrillation

Abstract

Background and Purpose-Warfarin reduces stroke risk by approximately 60% in patients with atrial fibrillation (AF).Differences in awareness and treatment of AF may contribute to racial and geographic disparities in stroke mortality.The objective was to examine predictors of awareness of the diagnosis of AF and treatment with warfarin. Methods-REasons for Geographic and Racial Differences in Stroke (REGARDS) is a national, population-based, longitudinal study of 30 239 blacks and whites Ն45 years old with oversampling from blacks and the southeastern stroke belt states. Participants were enrolled January 2003 to October 2007. Data were collected using telephone interview, in-home evaluation, and self-administered questionnaires. The main variable of awareness of AF was defined by a positive answer to "Has a doctor or other health professional ever told you that you had atrial fibrillation?" and whether there was evidence of treatment on the basis of an in-home medications inventory. Results-From baseline electrocardiograms, 432 individuals (88 black and 344 white) had AF. Of these, 88% (360 of 409) had at least 1 additional CHADS 2 stroke risk factor and 60% (258 of 432) were aware of their AF. The odds of blacks being aware of their AF were one third that of whites (ORϭ0.32; 95% CI: 0.20 to 0.52). Among those aware, the odds of blacks being treated with warfarin were only one fourth as great as whites (ORϭ0.28; 0.13 to 0.60). Conclusion-Blacks were less likely than whites to be aware of having AF or to be treated with warfarin. Potential reasons for the racial disparity in warfarin treatment warrant further investigation. (Stroke. 2010;41:581-587.)

Impact of Atrial Fibrillation on Healthcare Utilization in the Community: The Atherosclerosis Risk in Communities Study

“…Despite published disparities in AF treatment between men and women 32–34 and between white and black patients, 17–18,35 our study did not identify a differential impact of AF by sex or race on inpatient (MedPAR) or outpatient utilization; however, the numbers of women and black participants with AF were small and were from a small number of geographic areas, so it is possible that our study was underpowered to detect a difference.…”

Rates of Atrial Fibrillation in Black Versus White Patients With Pacemakers

“…These studies involved analysis of administrative claims data in all patients presenting for acute care,3 prospective ascertainment of AF based on periodic ECG screening and hospitalization records,4, 5, 6, 7, 8 or examination of electronic medical records to identify clinical diagnoses of AF or ECGs showing AF 9, 10. Because none of these approaches involved long‐term continuous heart‐rhythm monitoring, their results may have reflected differences in AF symptomatology or patterns of care between white and black patients that resulted in differential ascertainment of AF12, 13 rather than true differences in the burden of AF. A prospective study assessed racial differences in AF detection using pacemakers or implanted defibrillators, but this study included a small number of black patients and was able to adjust for a limited number of potentially confounding factors 11.…”

“…Conversely, studies consistently report that black patients have lower rates of atrial fibrillation (AF)—one of the strongest risk factors for stroke2—than white patients 3, 4, 5, 6, 7, 8, 9, 10, 11. It is unclear whether the lower reported rate of AF in black persons represents a truly lower burden of AF or more frequent underdiagnosis of this often paroxysmal dysrhythmia in black persons 12, 13. Better understanding of the true relative burden of AF in black persons may shed light on reasons for racial disparities in stroke rates that cannot be entirely accounted for by differences in demographic and socioeconomic characteristics or the prevalence of established stroke risk factors 14.…”

Atrial Fibrillation and the Risk of Myocardial Infarction

“…In the REGARDS study, our research group has previously shown that blacks and women are less likely to be aware of having AF or to be treated with warfarin. 24 The excess risk of MI coupled with the tendency to under-treat AF may magnify the risk of poor outcomes in these 2 groups.In a stratified analysis by warfarin use, the risk of MI associated with AF was lower in warfarin users than in nonusers, suggesting an effect modification by warfarin use. This accords with previous reports showing that warfarin might provide a protective effect against MI after acute coronary syndromes 25 and in patients with AF who are prescribed anticoagulation for stroke prevention.…”