Racial/Ethnic Disparities in Anticoagulation for Atrial Fibrillation by Sex and Within High and Low Stroke Risk Populations.

Atrial fibrillation (AF) increases the risk of thromboembolic stroke, and oral anticoagulants (OACs) are an effective tool to reduce this risk. Previous studies have demonstrated that female, black, Hispanic, and Asian groups are less likely to be prescribed OACs. This study explores OAC rates by racial/ethnic group and assesses differences within sexes and between high and low CHA₂DS₂-VASc risk groups. Using a database of AF patients, we employed logistic regression models to assess the association between race/ethnicity and OAC rates among all individuals and according to CHA₂DS₂-VASc risk and sex subgroups. Black, Hispanic, and Asian individuals with AF had lower OAC rates compared to white individuals (adjusted odds ratio [aOR], 0.84; 95% confidence interval [CI], 0.77-0.91) (aOR, 0.92; 95% CI, 0.85-0.99) (aOR, 0.80; 95% CI, 0.72-0.88). Female patients with AF had lower OAC rates than male patients (aOR, 0.66; 95% CI, 0.64-0.68). Among male patients, black, Hispanic, and Asian patients had lower OAC rates while, among female patients, only black patients had a lower OAC rate. In the low-risk CHA₂DS₂-VASc group, only Asian individuals had a lower OAC rate compared to white individuals, while, in the high-risk group, this trend was observed only for black individuals. Women, particularly black women, are less likely to receive OACs compared to men and their white counterparts. High-risk black individuals face reduced OAC use, while low-risk white individuals have high OAC rates. Subjective decision-making may contribute to these disparities, with the most significant disparities observed in black individuals, particularly black women. This "double hit" affecting black women could be the target of equity-focused interventions.