Abstract
Background
Studies of racial disparities in care of patients admitted with an out-of-hospital cardiac arrest (OHCA) in the setting of acute myocardial infarction (AMI) have shown inconsistent results. Whether these differences in care exist in the universal healthcare system in United Kingdom is unknown.
Methods
Patients admitted with a diagnosis of AMI and OHCA between 2010 and 2017 from the Myocardial Ischaemia National Audit Project (MINAP) were studied. All patients were stratified based on ethnicity into a Black, Asian, or minority ethnicity (BAME) group vs a White group. We used multivariable logistic regression models to evaluate the predictors of clinical outcomes and treatment strategy.
Results
From 14,287 patients admitted with AMI complicated by OHCA, BAME patients constituted a minority of patients (1185 [8.3%]), compared with a White group (13,102 [91.7%]). BAME patients were younger (median age [interquartile range]) for BAME group, 58 [50-70] years; for White group, 65 [55-74] years). Cardiogenic shock (BAME group, 33%; White group, 20.7%; P < 0.001) and severe left ventricular impairment (BAME group, 21%; White group, 16.5%; P < 0.003) were more frequent among BAME patients. BAME patients were more likely to be seen by a cardiologist (BAME group, 95.9%; White group, 92.5%; P < 0.001) and were more likely to receive coronary angiography than the White group (odds ratio [OR] 1.5, 95% confidence interval [CI] 1.2-1.88). The BAME group had significantly higher in-hospital mortality (OR 1.26, 95% CI 1.04-1.52) and re-infarction (OR 1.52, 95% CI 1.06-2.18) than the White group.
Conclusions
BAME patients were more likely to be seen by a cardiologist and receive coronary angiography than White patients. Despite this difference, the in-hospital mortality of BAME patients, particularly in the Asian population, was significantly higher.
Résumé
Introduction
Les études sur les inégalités raciales en matière de soins aux patients admis en raison d’un arrêt cardiaque hors de l’hôpital (ACHO) dans le cadre d’un infarctus aigu du myocarde (IAM) ont montré des résultats contradictoires. On ignore si ces différences en matière de soins existent dans le système de soins de santé universel de l’Angleterre.
Méthodes
Les patients admis en raison d’un diagnostic d’IAM et d’ACHO entre 2010 et 2017 du Myocardial Ischaemia National Audit Project (MINAP) ont fait l’objet de l’étude. Nous avons réparti tous les patients selon l’origine ethnique dans le groupe BAME (de l’anglais Black, Asian and minority ethnic, c.-à-d. Noirs, Asiatiques ou d’une minorité ethnique) vs le groupe des Blancs. Nous avons utilisé les modèles multivariés de régression logistique pour évaluer les prédicteurs des résultats cliniques et la stratégie de traitement.
Résultats
Parmi les 14 287 patients admis en raison d’un IAM compliqué par l’ACHO, les patients du BAME constituaient une minorité de patients (1 185 [8,3 %]) par rapport au groupe des Blancs (13 102 [91,7 %]). Les patients du groupe BAME étaient plus jeunes (âge médian [écart interquartile]), 58 [50-70] ans que le groupe des Blancs, 65 [55-74] ans). Le choc cardiogénique (groupe BAME, 33 %; groupe des Blancs, 20,7 %; P < 0,001) et l’insuffisance ventriculaire gauche grave (groupe BAME, 21 %; groupe des Blancs, 16,5 %; P < 0,003) étaient plus fréquents au sein des patients du BAME. Il était plus probable que les patients du BAME soient vus par un cardiologue (groupe du BAME, 95,9 %; groupe des Blancs, 92,5 %; P < 0,001) et qu’ils passent une angiographie coronarienne que le groupe des Blancs (ratio d’incidence approché [RIA] 1,5, intervalle de confiance [IC] à 95 % 1,2-1,88). Le groupe BAME avait une mortalité intrahospitalière (RIA 1,26, IC à 95 % 1,04-1,52) et une récidive d’infarctus (RIA 1,52, IC à 95 % 1,06-2,18) plus élevées que le groupe des Blancs.
Conclusions
Il était plus probable que les patients du BAME soient vus par un cardiologue et qu’ils passent une angiographie coronarienne que les patients blancs. Malgré cette différence, la mortalité intrahospitalière des patients du BAME, particulièrement de la population asiatique, était significativement plus élevée.
Out-of-hospital cardiac arrest (OHCA) is a major cause of cardiovascular mortality.
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Approximately 275,000 persons experience OHCA in Europe annually, with only 29,000 surviving to hospital discharge.
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are lacking. Data from the United Kingdom can give additional insights on the impact of racial disparities, because of differences in its population structure, compared with that in the US, and the availability of universal healthcare through the National Health Service (NHS). The NHS is a universal public sector system that provides universal access to health services to the whole population, independent of their socioeconomic status. In contrast, access to US healthcare systems and the quality of care received depend, to a greater extent, on patients’ socioeconomic status and medical insurance coverage. This means that individuals in the lower socioeconomic strata of society are unable to afford healthcare expenses, despite large governmental expenditure, placing the Black population at a disproportional disadvantage.
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We used the Myocardial Ischaemia National Audit Project (MINAP), a national registry of AMI hospitalizations in England and Wales, to study the impact of patients’ ethnicity on the processes of care and the clinical outcomes of patients admitted with AMI complicated by OHCA between 2010 and 2017.
Discussion
In this national cohort of AMI patients presenting with OHCA, the BAME patients were younger, had a relatively higher-risk comorbidity profile, and were sicker at the time of presentation, with a greater frequency of STEMI, cardiogenic shock, and severe left ventricular impairment, compared with the White population. BAME patients also had a relatively higher frequency of cardiovascular comorbidities such as diabetes, hypertension, and history of previous PCI. Administration of evidence-based medications and processes of care in BAME patients was often better, with BAME patients more likely to be seen by a cardiologist and to receive coronary angiography than the White population. Despite this, the in-hospital mortality rate of BAME patients was significantly higher than that of their White counterparts, with the worst outcomes seen in the Asian population.
Notably, BAME patients often had better administration of evidence-based medications and process of care, compared with the White population. The BAME population was much younger than the White population, sicker at the time of presentation, and had a higher prevalence of cardiovascular risk factors. These differences might have encouraged physicians to adopt a more invasive approach for management of the BAME patients. Furthermore, BAME patients were more likely to present with STEMI, which may also contribute to higher rates of coronary angiography use in this patient population. The MINAP registry does not capture data relating to optimization to target, which is an important component of quality of care, and so cannot inform as to whether there are significant differences in this factor in the patient groups studied.
Previous studies on the link between ethnicity and in-hospital management of OHCA revealed that ethnic minorities had a lower rate of inpatient cardiac procedures compared to Whites. For instance, a registry study from the Los Angeles County Emergency Medical Services system in 2019 revealed that minority groups, particularly the Black and Asian populations, had a lower frequency of in-hospital interventions, such as coronary angiography and PCI.
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In the current analysis of a national cohort of patients with AMI with OHCA from England and Wales, we report that BAME patients had better access to some aspects of inpatient management, such as receiving cardiologist input and use of coronary angiography and PCI. These findings suggest that, in contrast to findings in studies performed in the US, there are no significant racial disparities in the in-hospital management of AMI patients presenting with OHCA, and that the differences in the in-hospital processes of care might not contribute to the lower survival rate reported in BAME patients in the United Kingdom.
The low survival rates in BAME patients reported in the earlier studies from the US were attributed to different factors related to the community response, such as delayed identification of OHCA, longer response time, lack of awareness about OHCA management, and socioeconomic factors along with other social determinants of health.
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To the best of our knowledge, this is the first national study from Europe to address the racial disparities in management and outcomes of AMI complicated by OHCA. Our study shows that the crude mortality rate in the BAME population doubled over the study period, in contrast to that in the White population, for whom the in-hospital mortality rate remained relatively stable. Despite being younger and having similar in-hospital care, compared with the White population, BAME patients had higher odds of in-hospital death.
Survival following OHCA depends to a great extent on a “chain of survival” that begins with early recognition of OHCA and activation of the emergency response system, cardiopulmonary resuscitation (CPR), defibrillation, advanced life support, and integrated care after OHCA.
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For example, Sasson et al. analyzed a large cohort from the Cardiac Arrest Registry to Enhance Survival (CARES) registry in the US and found that patients who had an OHCA in low-income Black neighbourhoods were less likely to receive bystander-initiated CPR than those in high-income White neighbourhoods.
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they have a higher risk of delayed OHCA identification, a less-efficient chain of survival, and subsequently worse clinical outcomes. Moreover, neighbourhoods with a higher incidence of OHCA and low incidence of bystander CPR had a greater proportion of their populations from ethnic minority groups and people not born in the United Kingdom.
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The outcomes of the BAME group can be improved by providing training on CPR and defibrillators to the BAME community members, ensuring adequate availability of defibrillators in the neighbourhoods, and engaging the community centres and leaders in improving community awareness about the importance of the prehospital management of OHCA.
Our subgroup analysis showed that the Black population had similar survival and revascularization rates, compared with the White population, but the Asian population had a higher risk of in-hospital death and higher rates of coronary angiography and revascularization than the White population. In contrast to our results, the Shah et al. study on the outcomes of OHCA in the South Asian population revealed that the quality of care and admission to survival rates were comparable to those in the White population.
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The reasons behind the lower survival rates we reported for the Asian group cannot be fully explained by this study, especially with the small number of Black and Asian patients in the MINAP registry. Nonetheless, clinicians and policymakers may be interested in studying prehospital factors that may contribute to this lower rate, as a step toward reducing mortality in this group.
Strengths and limitations
One of the main strengths of this study is that we are able to study whether there are racial disparities in the management and outcomes for patients with AMI presenting with OHCA, from a national registry in which the data were collected prospectively over a long period of time. This study also has limitations that should be considered when interpreting the results. First, as the MINAP registry is an in-hospital AMI registry, it captures only patients with OHCA that complicates AMI, and patients who survived to hospital admission. It provides no insight into outcomes of other types of OHCA, for which there may also be racial disparities. Second, the MINAP database lacks information regarding long-term mortality and other outcomes, and does not capture the appropriateness of treatment decisions related to coronary angiography and inpatient management, nor adherence to and optimal titration of evidence-based medications. There are no data related to intensive-care management such as post-resuscitation cooling and ventilation. Finally, the MINAP registry does not provide any insight into the time to return of spontaneous circulation for those who experience OHCA in the community, or the management and quality of care prior to hospital admission. The MINAP registry does not capture whether differences in the processes of care between the 2 study groups is attributable to a higher prevalence of contraindications to coronary angiography in the White group. Although the MINAP registry provides insight about the neurologic deficit that occurs immediately after OHCA, it does not include information about long-term survival free from neurologic deficit.
Article info
Publication history
Published online: October 01, 2021
Accepted:
September 26,
2021
Received:
June 13,
2021
Footnotes
Ethics Statement: Ethical approval was not required for this study, under current arrangements by the National Health Service research governance body, because the MINAP database was collected and used for research purposes without informed patient consent by the National Institute for Cardiovascular Outcomes Research, under section 251 of the National Health Service Act of 2006.
See page S88 for disclosure information.
Copyright
© 2021 The Authors. Published by Elsevier Inc. on behalf of the Canadian Cardiovascular Society.