Association of Race and Ethnicity and Anticoagulation in Patients with Atrial Fibrillation Dually Enrolled in VA and Medicare: Effects of Medicare Part D on Prescribing Disparities

Association of care specialty with anticoagulant prescription and clinical outcomes in newly diagnosed atrial fibrillation: Results from the GARFIELD-AF registry

OBJECTIVE

To determine whether stroke prevention strategy, comorbidity management, and clinical outcome risks differ across atrial fibrillation (AF) care specialties.

METHODS

Newly diagnosed non-valvular AF patients enrolled in the international, prospective GARFIELD-AF registry (enrolment: 2010-2016) were analysed. Prescription of oral anticoagulation (OAC) therapy and select comorbidities was assessed by baseline care specialty: cardiology, primary care, or other specialties (internist/neurologist/geriatrician). Associations between care specialty and 2-year clinical outcomes were evaluated using multivariable Cox frailty models to account for within-country homogeneity.

RESULTS

In 52,011 patients, 34,172 (65.7 %) were diagnosed and initially managed in cardiology care, 7396 (14.2 %) in primary care, and 10,443 (20.1 %) in other specialties. The inter-country care specialty distribution varied considerably. Non-vitamin K OAC (NOAC) therapy among CHA2DS2-VASc ≥2 patients was more common in cardiology care (31.0 %) than primary care (19.8 %) and other specialty care (24.9 %), but comorbidity management was similar across specialties. Compared to cardiology care, primary care was associated with greater non-cardiovascular mortality (1.21 [1.01-1.45]), major bleeding (1.31 [1.05-1.62]), and new/worsening heart failure risk (2.09 [1.69-2.59]). Care in other specialties was associated with greater all-cause (adjusted hazard ratio, 1.19 [95 % CI, 1.09-1.29]), cardiovascular (1.15 [1.01-1.31]), and non-cardiovascular mortality (1.29 [1.13-1.47]), as well as non-haemorrhagic stroke/systemic embolism (1.48 [1.26-1.73]), major bleeding (1.21 [1.02-1.43]), and new/worsening heart failure risk (1.45 [1.21-1.75]) than cardiology care.

CONCLUSION

Comorbidity management was similar across AF care specialties, but patients outside of cardiology care had fewer NOAC prescriptions and greater risk for most clinical endpoints. Cardiology expertise may have important implications for AF prognosis.

CLINICAL TRIAL REGISTRATION

URL: http://www.

CLINICALTRIALS

gov. Unique identifier for GARFIELD-AF: NCT01090362.

Measuring Representativeness in Clinical Trials

Representativeness in randomized clinical trials remains a critical concern, affecting the external validity of trial results, equitable access to the risks and benefits of research participation, and public trust in clinical research. Although representative participation by members of groups traditionally underrepresented in clinical trials is just a surrogate for true diversity, equity, inclusion, and belonging in clinical trials, it can be quantified, allowing stakeholders to add empirical rigor to diversity, equity, inclusion, and belonging efforts. Multiple ways to measure representativeness have been proposed, including the participation-to-prevalence ratio, raw participation proportions or numbers for relevant subgroups, and enrollment fraction for relevant subgroups. These methods have strengths and weaknesses and may be appropriate to report in certain circumstances, depending on why stakeholders seek to assess representativeness. Stakeholders-including regulatory agencies, journal editors, clinical trial investigators, and trial sponsors-may use quantitative measures of representativeness to establish trial enrollment standards, monitor equitable participation in ongoing trials, and condition funding or drug or device approval on achieving specific representativeness targets. However, using quantitative measures of representativeness in this way could have unintended consequences, including researchers "gaming" recruitment strategies to meet target numbers, overlooking nuanced variations within communities, and potentially incentivizing problematic and exploitative recruitment strategies. Although no single method of measuring representativeness offers a comprehensive solution for increasing diversity, equity, inclusion, and belonging in all randomized clinical trials, a carefully designed, multifaceted approach to measuring representativeness may provide stakeholders with useful perspectives for measuring progress in increasing the diversity of clinical trial participation. For stakeholders seeking a single number to assess the representativeness of a trial enrolling patients with a disease state with well-delineated demographics, the participation-to-prevalence ratio is ideal; however, for a more nuanced view of representativeness, the combination of enrollment fraction in subgroups of relevance plus a full report of the demographics of patients approached for enrollment may be more appropriate.

National Trends in Racial and Ethnic Disparities in Mortality from Mechanical Complications of Cardiac Valves and Grafts (1999-2020)

Background: The volume of cardiac valve and coronary artery revascularization procedures is rising in the United States. This cross-sectional study explores ethnic disparities in mortality in cardiac surgery attributed to mechanical failures of implantable heart valves and coronary artery grafts. Methods: We used the CDC Wide-Ranging Online Data for Epidemiologic Research Multiple Causes of Death database to identify patients whose single cause of death was categorized by complications of cardiovascular prosthetic devices, implants, and grafts (ICD-10 code T82) between 1999 and 2020. The Joinpoint software (version 5.2.0, National Cancer Institute) was used to construct log-linear regression models to estimate the average annual percent changes in age-adjusted mortality (per 100,000). These patterns were compared and stratified by sex, age (0-44, 44-64, and 65 years or older), and US census regions between White, Black, Hispanic, non-Hispanic, American Indian, Alaskan Native, Asian American, and Pacific Islanders. Results: Age-adjusted mortality due to mechanical failures of cardiac implants and grafts declined across ethnicities from 2.21 (95% CI 2.16-2.27) in 1999 to 0.88 (95% CI 0.85-0.91) in 2020. Black populations (1.31 [95% CI 1.20-1.42]), both men (1.56 [95% CI 1.37-1.74]) and women (1.02 [95% CI 0.90-1.15]) experienced higher mortality in 2020 compared to all other ethnicities. This disparity was pronounced in younger groups (age 0-64), wherein age-adjusted mortality among Black populations (0.18 [95% CI 0.13-0.25]) more than doubled that of White populations (0.08 [95% CI 0.06-0.10]). Conclusions: Over the last two decades, age-adjusted mortality due to mechanical complications of cardiovascular implants has declined significantly. However, Black men and women, particularly younger patients, continue to experience higher death rates compared to other ethnicities.

Systemic infarcts among patients with atrial fibrillation

BACKGROUND

The epidemiology of atrial fibrillation (AF)-associated thromboembolic complications outside of ischemic strokes has not been thoroughly elucidated.

OBJECTIVE

The aim of this study was to describe the epidemiology of AF-associated systemic infarcts and relevant interactions by sex and race/ethnicity.

METHODS

Using the Office of Statewide Health Planning and Development, we performed a longitudinal analysis of patients aged ≥18 years who received ambulatory surgery, emergency, or inpatient medical care in California between 2005 and 2015. We determined the distribution of infarct locations and risks of systemic infarcts for patients with AF. Interaction analyses by sex and race/ethnicity were conducted.

RESULTS

Of 1,321,694 patients with AF, the average annual rate of systemic infarct was 2.1% ± 0.18% compared with 0.56% ± 0.06% in the 22,944,488 patients without AF. The increased frequency of these infarcts was observed for every body area investigated. After adjustment for potential confounders and mediators, patients with AF experienced a 45% increased risk of a systemic infarct (hazard ratio, 1.45; 95% confidence interval, 1.44-1.47; P < .001). Women, Asians, Blacks, and Hispanics each exhibited a statistically significant heightened relative risk of systemic infarcts in the presence of AF.

CONCLUSION

AF increases the risk of infarcts throughout the body. Susceptibility to these systemic infarcts varies by sex and race/ethnicity in patterns similar to differential risks for stroke. The presence of a systemic infarct in the absence of a clear cause should raise suspicion for AF, and the potential benefits of AF prevention and anticoagulation should be considered beyond only infarcts to the brain.

Differences in quality of anticoagulation care delivery according to ethnoracial group in the United States: A scoping review

Anticoagulation therapy is standard for conditions like atrial fibrillation, venous thromboembolism, and valvular heart disease, yet it is unclear if there are ethnoracial disparities in its quality and delivery in the United States. For this scoping review, electronic databases were searched for publications between January 1, 2011 - March 30, 2022. Eligible studies included all study designs, any setting within the United States, patients prescribed anticoagulation for any indication, outcomes reported for ≥ 2 distinct ethnoracial groups. The following four research questions were explored: Do ethnoracial differences exist in 1) access to guideline-based anticoagulation therapy, 2) quality of anticoagulation therapy management, 3) clinical outcomes related to anticoagulation care, 4) humanistic/educational outcomes related to anticoagulation therapy. A total of 5374 studies were screened, 570 studies received full-text review, and 96 studies were analyzed. The largest mapped focus was patients' access to guideline-based anticoagulation therapy (88/96 articles, 91.7%). Seventy-eight articles made statistical outcomes comparisons among ethnoracial groups. Across all four research questions, 79 articles demonstrated favorable outcomes for White patients compared to non-White patients, 38 articles showed no difference between White and non-White groups, and 8 favored non-White groups (the total exceeds the 78 articles with statistical outcomes as many articles reported multiple outcomes). Disparities disadvantaging non-White patients were most pronounced in access to guideline-based anticoagulation therapy (43/66 articles analyzed) and quality of anticoagulation management (19/21 articles analyzed). Although treatment guidelines do not differentiate anticoagulant therapy by ethnoracial group, this scoping review found consistently favorable outcomes for White patients over non-White patients in the domains of access to anticoagulation therapy for guideline-based indications and quality of anticoagulation therapy management. No differences among groups were noted in clinical outcomes, and very few studies assessed humanistic or educational outcomes.

Veterans Affairs Medical Center Racial and Ethnic Composition and Initiation of Anticoagulation for Atrial Fibrillation

Importance

Racial and ethnic disparities exist in anticoagulation therapy for atrial fibrillation (AF). Whether medical center racial and ethnic composition is associated with these disparities is unclear.

Objective

To determine whether medical center racial and ethnic composition is associated with overall anticoagulation and disparities in anticoagulation for AF.

Design, Setting, and Participants

Retrospective cohort study of Black, White, and Hispanic patients with incident AF from 2018 to 2021 at 140 Veterans Health Administration medical centers (VAMCs). Data were analyzed from March to November 2023.

Exposure

VAMC racial and ethnic composition, defined as the proportion of patients from minoritized racial and ethnic groups treated at a VAMC, categorized into quartiles. VAMCs in quartile 1 (Q1) had the lowest percentage of patients from minoritized groups (ie, the reference group).

Main Outcomes and Measures

The odds of initiating any anticoagulant, direct-acting oral anticoagulant (DOAC), or warfarin therapy within 90 days of an index AF diagnosis, adjusting for sociodemographics, medical comorbidities, and facility factors.

Results

The cohort comprised 89 791 patients with a mean (SD) age of 73.0 (10.1) years; 87 647 (97.6%) were male, 9063 (10.1%) were Black, 3355 (3.7%) were Hispanic, and 77 373 (86.2%) were White. Overall, 64 770 individuals (72.1%) initiated any anticoagulant, 60 362 (67.2%) initiated DOAC therapy, and 4408 (4.9%) initiated warfarin. Compared with White patients, Black and Hispanic patients had lower rates of any anticoagulant and DOAC therapy initiation but higher rates of warfarin initiation across all quartiles of VAMC racial and ethnic composition. Any anticoagulant therapy initiation was lower in Q4 than Q1 (69.8% vs 74.9%; adjusted odds ratio [aOR], 0.80; 95% CI, 0.69-0.92; P < .001). DOAC and warfarin initiation were also lower in Q4 than in Q1 (DOAC, 69.4% vs 65.3%; aOR, 0.85; 95% CI, 0.74-0.97; P < .001; warfarin, 5.4% vs 4.5%; aOR, 0.82; 95% CI, 0.67-1.00; P < .001). In adjusted models, patients in Q4 were significantly less likely to initiate any anticoagulant therapy than those in Q1 (aOR, 0.88; 95% CI, 0.78-0.99). Patients in Q3 (aOR, 0.75; 95% CI, 0.60-0.93) and Q4 (aOR, 0.69; 95% CI, 0.55-0.87) were significantly less likely to initiate warfarin therapy than those in Q1. There was no significant difference in the adjusted odds of initiating DOAC therapy across racial and ethnic composition quartiles. Although significant Black-White and Hispanic-White differences in initiation of any anticoagulant, DOAC, and warfarin therapy were observed, interactions between patient race and ethnicity and VAMC racial composition were not significant.

Conclusions and Relevance

In a national cohort of VA patients with AF, initiation of any anticoagulant and warfarin, but not DOAC therapy, was lower in VAMCs serving more minoritized patients.

Facility-Level Variation in Racial Disparities in Anticoagulation for Atrial Fibrillation: The REACH-AF Study

BACKGROUND

Oral anticoagulation reduces stroke risk for patients with atrial fibrillation (AF). Prior research demonstrates lower anticoagulant prescribing in Black than in White individuals but few studies have examined racial differences in facility-level anticoagulant prescribing for AF.

OBJECTIVE

To assess variation in anticoagulant initiation by race within Veterans Health Administration (VA) facilities.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Black and White patients enrolled in the VA with incident AF from 2020 through 2021.

MAIN MEASURES

The primary outcome was rate of any anticoagulant initiation (i.e., warfarin or direct oral anticoagulant [DOAC]) or any DOAC therapy within 90 days of an AF diagnosis, overall and for Black and White patients at each facility. We also estimated the adjusted Black-White risk difference.

KEY RESULTS

In 82 VA facilities serving 26,832 Black and White patients, overall unadjusted rates of any anticoagulant therapy ranged from 56.8 to 87.1% across facilities; the corresponding ranges for Black and White patients were 47.6 to 91.3% and 58.2 to 87.1%, respectively. Overall unadjusted rates of DOAC therapy ranged from 55.1 to 85.5% by facility; ranges for Black and White patients were 42.8 to 86.9% and 56.4 to 85.5%, respectively. The adjusted risk difference between Black and White patients ranged from - 29.9 (95% CI, - 54.9 to - 4.8) to 14.2 (95% CI, - 9.1 to 25.0) across facilities for any anticoagulant therapy and from - 28.8 (95% CI, - 58.3 to 0.8) to 15.0 (95% CI, - 8.0 to 38.1) for DOAC therapy. For any anticoagulant therapy there were 3 facilities where prescribing was statistically higher in White than Black patients; for DOAC therapy there were 5 such facilities.

CONCLUSIONS

In a national cohort of patients with AF, we observed large facility-level variation and adjusted risk differences in any anticoagulant and DOAC initiation, overall and by race. These findings represent a target for local quality improvement in AF care.

Oral anticoagulation therapy initiation in patients with atrial fibrillation in relation to world region of origin: a register-based nationwide study

BACKGROUND

Atrial fibrillation (AF) is the most common sustained arrhythmia and results in a high risk of stroke. The number of immigrants is increasing globally, but little is known about potential differences in AF care across migrant populations.

AIM

To investigate if initiation of oral anticoagulation therapy (OAC) differs for patients with incident AF in relation to country of origin.

METHODS

A nationwide register-based study covering 1999-2017. AF was defined as a first-time diagnosis of AF and a high risk of stroke. Stroke risk was defined according to guidelines from the European Society of Cardiology (ESC). Poisson regression adjusted for sex, age, socioeconomic position and comorbidity was made to compute incidence rate ratios (IRR) for initiation of OAC.

RESULTS

The AF population included 254 586 individuals of Danish origin, 6673 of Western origin and 3757 of non-Western origin. Overall, OAC was initiated within -30/+90 days relative to the AF diagnosis in 50.3% of individuals of Danish origin initiated OAC, 49.6% of Western origin and 44.5% of non-Western origin. Immigrants from non-Western countries had significantly lower adjusted IRR of initiating OAC according to all ESC guidelines compared with patients of Danish origin. The adjusted IRRs ranged from 0.73 (95% CI: 0.66 to 0.80) following the launch of the 2010 ESC guideline to 0.89 (95% CI: 0.82 to 0.97) following the launch of the 2001 ESC guideline.

CONCLUSION

Patients with AF with a high risk of stroke of non-Western origin have persistently experienced a lower chance of initiating OAC compared with patients of Danish origin during the last decades.

Eliminating Health Disparities in Atrial Fibrillation, Heart Failure, and Dyslipidemia: A Path Toward Achieving Pharmacoequity

PURPOSE OF REVIEW

Pharmacoequity refers to the goal of ensuring that all patients have access to high-quality medications, regardless of their race, ethnicity, gender, or other characteristics. The goal of this article is to review current evidence on disparities in access to cardiovascular drug therapies across sociodemographic subgroups, with a focus on heart failure, atrial fibrillation, and dyslipidemia.

RECENT FINDINGS

Considerable and consistent disparities to life-prolonging heart failure, atrial fibrillation, and dyslipidemia medications exist in clinical trial representation, access to specialist care, prescription of guideline-based therapy, drug affordability, and pharmacy accessibility across racial, ethnic, gender, and other sociodemographic subgroups. Researchers, health systems, and policy makers can take steps to improve pharmacoequity by diversifying clinical trial enrollment, increasing access to inpatient and outpatient cardiology care, nudging clinicians to increase prescription of guideline-directed medical therapy, and pursuing system-level reforms to improve drug access and affordability.

Disparities in Antifibrotic Medication Utilization Among Veterans With Idiopathic Pulmonary Fibrosis

BACKGROUND

Two antifibrotic medications, pirfenidone and nintedanib, are approved for the treatment of idiopathic pulmonary fibrosis (IPF). Little is known about their real-world adoption.

RESEARCH QUESTION

What are the real-world antifibrotic utilization rates and factors associated with uptake among a national cohort of veterans with IPF?

STUDY DESIGN AND METHODS

This study identified veterans with IPF who received care either provided by the Veterans Affairs (VA) Healthcare System or non-VA care paid for by the VA. Patients who had filled at least one antifibrotic prescription through the VA pharmacy or Medicare Part D between October 15, 2014, and December 31, 2019, were identified. Hierarchical logistic regression models were used to examine factors associated with antifibrotic uptake, accounting for comorbidities, facility clustering, and follow-up time. Fine-Gray models were used to evaluate antifibrotic use by demographic factors, accounting for the competing risk of death.

RESULTS

Among 14,792 veterans with IPF, 17% received antifibrotics. There were significant disparities in adoption, with lower uptake associated with female sex (adjusted OR, 0.41; 95% CI, 0.27-0.63; P < .001), Black race (adjusted OR, 0.60; 95% CI, 0.49-0.73; P < .001), and rural residence (adjusted OR, 0.88; 95% CI, 0.80-0.97; P = .012). Veterans who received their index diagnosis of IPF outside the VA were less likely to receive antifibrotic therapy (adjusted OR, 0.15; 95% CI, 0.10-0.22; P < .001).

INTERPRETATION

This study is the first to evaluate the real-world adoption of antifibrotic medications among veterans with IPF. Overall uptake was low, and there were significant disparities in use. Interventions to address these issues deserve further investigation.

Comparative Effectiveness of Anticoagulants in Patients With Cancer-Associated Thrombosis

Importance

Patterns of clinical utilization and comparative effectiveness of anticoagulants for cancer-associated thrombosis (CAT) remain largely unexplored.

Objectives

To assess patterns of and factors associated with anticoagulant use and to evaluate the comparative effectiveness of contemporary anticoagulants in patients with active cancer in a clinical setting.

Design, Setting, and Participants

This retrospective cohort study obtained deidentified OptumLabs electronic health record claims data from January 1, 2012, to September 30, 2019. Adult patients (≥18 years of age) with a primary cancer diagnosis (except skin cancer) during at least 1 inpatient or 2 outpatient visits within 6 months before the venous thromboembolism (VTE) date were included. Data were analyzed from April 2020 to September 2021.

Exposures

The patients were grouped according to the anticoagulant prescribed: (1) direct oral anticoagulants (DOACs), (2) low-molecular-weight heparin (LMWH), and (3) warfarin.

Main Outcomes and Measures

Odds ratios (ORs) were used to present the association between factors of interest and utilization of anticoagulants. Main efficacy outcomes included risk of VTE recurrence and all-cause mortality. Main safety outcomes included the risk of hospitalization due to major bleeding. Relative treatment effect estimates were expressed as hazard ratios (HRs) with 95% CIs.

Results

This study included 5100 patients (mean [SD] age, 66.3 [12.3] years; 2670 [52.4%] women; 799 [15.7%] Black, 389 [7.6%] Hispanic, and 3559 [69.8%] White individuals). Overall, 2512 (49.3%), 1488 (29.2%), and 1460 (28.6%) filled prescriptions for DOACs, LMWH, and warfarin, respectively. The median (IQR) treatment duration was 3.2 (1.0-6.5) months for DOACs, 3.1 (1.0-6.8) months for warfarin, and 1.8 (0.9-3.8) months for LWMH. Patients with lung (OR, 2.07; 95% CI, 1.12-3.65), urological (OR, 1.94; 95% CI,1.08-3.49), gynecological (OR, 4.25; 95% CI, 2.31-7.82), and colorectal (OR, 2.26; 95% CI, 1.20-4.32) cancer were associated with increased prescriptions for LMWH compared with DOACs. LMWH (HR, 1.47; 95% CI, 1.14-1.90) and warfarin (HR, 1.46; 95% CI, 1.13-1.87) were associated with an increased risk of VTE recurrences compared with DOACs. LMWH was associated with an increased risk of major bleeding (HR, 2.27; 95% CI, 1.62-3.20) and higher all-cause mortality (HR, 1.61; 95% CI, 1.15-2.25) compared with DOACs.

Conclusions and Relevance

In this comparative effectiveness study of claims-based data, patients with CAT received anticoagulation for a remarkably short duration in clinical settings. DOACs was associated with a lower risk of VTE recurrence, major bleeding, and mortality. Warfarin may still be considered for patients with contraindications to DOACs and those with poor persistence on LMWH.

Association of Neighborhood Disadvantage and Anticoagulation for Patients with Atrial Fibrillation in the Veterans Health Administration: the REACH-AF Study

BACKGROUND

Atrial fibrillation (AF) is a common arrhythmia, the management of which includes anticoagulation for stroke prevention. Although disparities in anticoagulant prescribing have been well documented for individual socioeconomic factors, less is known about the association of neighborhood-level disadvantage and anticoagulation for AF.

OBJECTIVE

To assess the association between neighborhood disadvantage and anticoagulant initiation for patients with incident AF.

DESIGN

Retrospective cohort study.

PARTICIPANTS

A cohort of patients enrolled in the Veterans Health Administration (VA) with incident AF from January 2014 through December 2020 from the Race, Ethnicity, and Anticoagulant CHoice in Atrial Fibrillation (REACH-AF) Study.

MAIN MEASURES

The primary exposure was neighborhood disadvantage quantified using area deprivation index (ADI), classified by quintiles (Q). The outcomes were initiation of any anticoagulant therapy (warfarin or direct oral anticoagulant, DOAC) within 90 days of AF diagnosis and DOAC use among initiators. We used mixed effects logistic regression to assess the association between ADI and anticoagulant therapy, incorporating a fixed effect for treatment site and baseline patient, provider, and facility covariates.

KEY RESULTS

Among 161,089 patients, 105,489 (65.5%) initiated any anticoagulant therapy, and 78,903 (74.8%) used DOACs. Any anticoagulant therapy increased 3.2 percentage points (63.0% to 66.2%; p<.001) from Q1 to Q5, whereas DOAC use decreased 8.2 percentage points (79.4% to 71.2%; p<.0001) across quintiles. The adjusted odd ratios of any anticoagulant therapy were non-significantly different for Q2-Q5 than Q1. The adjusted odds of DOAC use decreased progressively from 0.89 (95% CI, 0.84-0.94) in Q2 to 0.77 (95% CI, 0.73-0.83) in Q5 compared to Q1 (p<.0001).

CONCLUSIONS

Among Veterans with incident AF, we observed similar initiation of any anticoagulant, though neighborhood deprivation was associated with decreased DOAC use among anticoagulant initiators. Future interventions to improve pharmacoequity in anticoagulant prescribing for AF should consider the role of neighborhood-level determinants of health inequities.

Racial Differences in Atrial Fibrillation Management Between White Patients and Black Patients in Transthyretin Cardiac Amyloid

Black patients have higher rates of stroke than White patients. Paradoxically, atrial fibrillation (AF) affects twice as many White patients compared with Black patients. Transthyretin cardiac amyloidosis (ATTR-CA) is associated with both AF and strokes. We hypothesized that although Black patients with ATTR-CA have a lower incidence of AF, when diagnosed with AF, they have increased thromboembolic events. Patients with ATTR-CA (n = 558) at 3 international centers were retrospectively identified. We compared baseline characteristics, presence of AF, outcomes of thromboembolism (stroke, transient ischemic attack, and peripheral embolism), major bleed, and mortality by race. Of all patients, 367 of 488 White patients (75%) were diagnosed with AF compared with 39 of 70 Black patients (56%) (p = 0.001). Black patients with AF had a hazard ratio of 5.78 (95% confidence interval 2.30 to 14.50) for time to first thromboembolic event compared with White patients. There were no racial differences in major bleeding. Black patients with AF more often lacked anticoagulation (p = 0.038) and had higher incidence of labile international normalized ratio (p <0.001). In conclusion, these data suggest that although Black patients with ATTR-CA have lower incidence of AF, they have increased thromboembolic events compared with White patients. These findings may be related to treatment discrepancies, time in therapeutic range for warfarin, and disparities in healthcare.

Association of Race and Ethnicity With Oral Anticoagulation and Associated Outcomes in Patients With Atrial Fibrillation: Findings From the Get With The Guidelines-Atrial Fibrillation Registry

Importance

Oral anticoagulation (OAC) is underprescribed in underrepresented racial and ethnic group individuals with atrial fibrillation (AF). Little is known of how differential OAC prescribing relates to inequities in AF outcomes.

Objective

To compare OAC use at discharge and AF-related outcomes by race and ethnicity in the Get With The Guidelines-Atrial Fibrillation (GWTG-AFIB) registry.

Design, Setting, and Participants

This retrospective cohort analysis used data from the GWTG-AFIB registry, a national quality improvement initiative for hospitalized patients with AF. All registry patients hospitalized with AF from 2014 to 2020 were included in the study. Data were analyzed from November 2021 to July 2022.

Exposures

Self-reported race and ethnicity assessed in GWTG-AFIB registry.

Main Outcomes and Measures

The primary outcome was prescription of direct-acting OAC (DOAC) or warfarin at discharge. Secondary outcomes included cumulative 1-year incidence of ischemic stroke, major bleeding, and mortality postdischarge. Outcomes adjusted for patient demographic, clinical, and socioeconomic characteristics as well as hospital factors.

Results

Among 69 553 patients hospitalized with AF from 159 sites between 2014 and 2020, 863 (1.2%) were Asian, 5062 (7.3%) were Black, 4058 (5.8%) were Hispanic, and 59 570 (85.6%) were White. Overall, 34 113 (49.1%) were women; the median (IQR) age was 72 (63-80) years, and the median (IQR) CHA2DS2-VASc score (calculated as congestive heart failure, hypertension, age 75 years and older, diabetes, stroke or transient ischemic attack, vascular disease, age 65 to 74 years, and sex category) was 4 (2-5). At discharge, 56 385 patients (81.1%) were prescribed OAC therapy, including 41 760 (74.1%) receiving DOAC. OAC prescription at discharge was lowest in Hispanic patients (3010 [74.2%]), followed by Black patients (3935 [77.7%]) Asian patients (691 [80.1%]), and White patients (48 749 [81.8%]). Black patients were less likely than White patients to be discharged while taking any anticoagulant (adjusted odds ratio, 0.75; 95% CI, 0.68-0.84) and DOACs (adjusted odds ratio, 0.73; 95% CI, 0.65-0.82). In 16 307 individuals with 1-year follow up data, bleeding risks (adjusted hazard ratio [aHR], 2.08; 95% CI, 1.53-2.83), stroke risks (aHR, 2.07; 95% CI, 1.34-3.20), and mortality risks (aHR, 1.22; 95% CI, 1.02-1.47) were higher in Black patients than White patients. Hispanic patients had higher stroke risk (aHR, 2.02; 95% CI, 1.38-2.95) than White patients.

Conclusions and Relevance

In a national registry of hospitalized patients with AF, compared with White patients, Black patients were less likely to be discharged while taking anticoagulant therapy and DOACs in particular. Black and Hispanic patients had higher risk of stroke compared with White patients; Black patients had a higher risk of bleeding and mortality. There is an urgent need for interventions to achieve pharmacoequity in guideline-directed AF management to improve overall outcomes.