Racial and Ethnic Differences in Acute Coronary Syndrome and Myocardial Infarction Within the United States: From Demographics to Outcomes

ABSTRACT

In the United States, different races, ethnicities, and their subgroups experience disparities regarding acute coronary syndrome (ACS) and myocardial infarction (MI). This review highlights these differences across 4 stages that comprise the ACS/MI narrative: (1) patient demographics, (2) patient comorbidities and health risks, (3) treatments and their delays, and (4) outcomes. Overall, black and Hispanic ACS/MI patients are more likely to present with comorbidities, experience longer delays before treatment, and suffer worse outcomes when compared with non‐Hispanic white patients. More specifically, across the studies analyzed, black and Hispanic ACS/MI patients were consistently more likely to be younger or female, or to have hypertension or diabetes, than non‐Hispanic white patients. ACS/MI disparities also exist among Asian populations, and these are briefly outlined. However, black, Hispanic, and non‐Hispanic white ACS/MI patients were the 3 most‐studied racial and ethnic groups, indicating that additional studies of other minority groups, such as Native Americans, Asian populations, and black and Hispanic subgroups, are needed for their utility in reducing disparities. Despite notable improvement in ACS/MI treatment quality measures over recent decades, disparities persist. Causes are complex and extend beyond the healthcare system to culture and patients' personal characteristics; sophisticated solutions will be required. Continued research has the potential to further reduce or eliminate disparities in the comorbidities, delays, and treatments surrounding ACS and MI, extending healthy lifespans of many underserved and minority populations, while reducing healthcare costs.

Introduction

Significant disparities continue to persist in cardiovascular care of racial and ethnic minorities, even after adjusting for patient income, education, and site of care.1 Many of these disparities can be attributed to a preponderance of cardiometabolic risk factors among minority groups, including diabetes, hypertension, obesity, dyslipidemia, and metabolic syndrome. Other possible explanations for disparities in care include socioeconomic factors such as type of health insurance, lack of access to high‐quality care, insufficient preventative medicine, or inadequate education regarding healthy habits and medication adherence. Eliminating racial and ethnic cardiovascular health disparities could prevent an estimated 1.1 million hospitalizations annually.2

This review presents disparities experienced by different races, ethnicities, and their subgroups related to acute coronary syndrome (ACS) and myocardial infarction (MI) in the United States. Differences discussed include patient demographics, patient comorbidities and health risks, treatments and their delays, and outcomes. This review is unique in that it lays out the spectrum of disparities across a variety of different populations and presents updated information.

Disparities Among African Americans

Demographics

Overall, black patients presenting with ACS or MI tend to be younger than white patients, have less education and lower income, and be covered by Medicaid or have no insurance at all.3, 4, 5, 6, 7 In a study of over 2 million acute myocardial infarction (AMI) hospitalizations from the Quality Improvement Organization Clinical Data Warehouse of the Centers for Medicare and Medicaid Services (QIOCDW‐CMMS), black patients were younger than white AMI patients and were more likely to be female.7

Comorbidities

Cardiometabolic comorbidities are more prevalent in blacks, including dyslipidemia, hypertension, obesity, insulin resistance, hyperglycemia, chronic kidney disease, and diabetes mellitus.2 Additional studies have noted the increased prevalence of these and other diseases and risk factors.2, 4, 5, 6, 8, 9 Blacks also have a higher prevalence of cardiovascular disease (CVD) than whites; 44.4% of black men have CVD (vs 36.6% of white men), and 48.9% of black women have CVD (vs 32.4% of white women).10 Within each age–sex group in the Prospective Registry Evaluating Myocardial Infarction: Events and Recovery (PREMIER) study,9 the prevalence of hypercholesterolemia and obesity did not differ significantly by race, but the prevalence of multiple cardiac risk factors was significantly higher for blacks than for whites.8 Adherence to medications prior to admission for ACS has also been found to differ, as nonwhite patients in the Treat Angina With Aggrastat and Determine the Cost of Therapy With an Invasive or Conservative Strategy (TACTICS‐TIMI‐18) trial were significantly less likely to be taking their cardiac medications than whites.11

Treatment and Medication

Overall, black patients have been found to experience longer delays in receiving drug or surgical treatments compared to white patients. Black patients in the Think Symptoms study had significantly longer prehospital delays than whites.6 In a large cohort of patients from the National Registry of Myocardial Infarction, door‐to‐drug times were longest for black patients and door‐to‐balloon times were significantly longer for blacks than for whites.12 In a study of patients undergoing primary percutaneous coronary intervention (PCI) as part of the American Heart Association Get With The Guidelines (GWTG) study, insignificant differences were found in door‐to‐balloon times between white and black patients, with similar in‐hospital mortality rates between groups.13 However, after adjusting for confounding factors, being black was associated with a lower likelihood of door‐to‐balloon times of <90 minutes (a quality‐of‐care indicator for treatment of ST‐segment elevation myocardial infarction [STEMI]) relative to being white.13

In a study of Medicare beneficiaries with AMI who were admitted to hospitals without revascularization facilities, it was found that it took a median of 2 days to transfer black patients to a revascularization hospital, but a median of 1 day for whites (risk‐standardized mortality rate in the revascularization hospitals did not differ between black and white patients).14 In a cohort of 1 215 924 black and white Medicare beneficiaries (≥68 years) admitted with AMI between 2000 and 2005, black patients admitted to nonrevascularization hospitals were significantly less likely to be transferred to a hospital with revascularization facilities, and significantly less likely to receive revascularization than white patients. After adjustment for sociodemographics, comorbidity, and severity of disease, the disparities between transfer and revascularization rates remained significant.15

County‐level hospital capacity, measured as the number of cardiac revascularization hospitals per capita, may explain some of the observed racial disparity in treatment of PCI and coronary artery bypass graft (CABG). To gauge the impact of this factor, 1 study assessed data from 207 570 Medicare patients admitted for AMI in Pennsylvania (between 1995 and 2006).16, 17 Blacks were significantly less likely than whites to be treated with either CABG or PCI within 3 months of AMI. Furthermore, this racial disparity in CABG treatment remained similar in counties with differing AMI hospital capacity, whereas the PCI rate disparity was larger in counties with the lowest AMI hospital capacity.17

Outcomes

The BCBS‐MICC (Blue Cross Blue Shield of Michigan Cardiovascular Consortium) study found no differences in in‐hospital mortality rates between whites and blacks,4 and in the analysis of 12 555 AMI patients in New York City, investigators also found no significant difference in survival rates.3 Furthermore, among patients who were not revascularized, blacks were more likely to survive and be discharged than whites.3 However, nonwhite patients in the TACTICS‐TIMI‐18 trial had less procedural success with PCI than white patients, and had a significantly higher risk of death, recurrent MI, or rehospitalization (and worse prognosis) after adjustment for patients' baseline medical characteristics.11 One month postadmission for ACS, blacks at their follow‐up reported significantly more symptoms and more clinic visits than whites. Blacks continued to have more symptoms at 6 months post‐ACS, but health service usage no longer differed.6

Changes in the incidence of mortality and 1‐year recurrent AMI hospitalization were analyzed across more than 2 million Medicare beneficiaries from 1999 to 2010. All‐cause 1‐year mortality declined in both sexes and races, with the largest decline among patients age 75 to 84 years. Despite these across‐the‐board improvements, the proportional decline in recurrent AMI rehospitalization was larger in whites (27.7%) than in blacks (13.6%), so that at the end of the study period, the discrepancy between whites and blacks had actually increased.18

Disparities Among Hispanic Americans

Demographics

The US Hispanic population is very heterogeneous: genetic backgrounds, sociocultural experiences, health behaviors, and environmental exposures vary widely.19 Overall, Hispanic patients presenting with ACS or MI are younger than white patients and are more likely to be uninsured.3, 7, 19, 20, 21 In a study of over 2 million AMI hospitalizations, Hispanic AMI patients were found to be younger than white AMI patients.7 Among patients presenting with non–ST‐segment elevation (NSTE) ACS from the National Registry of Acute Ischemic Coronary Syndromes (RENASICA) and Can Rapid Risk Stratification of Unstable Angina Patients Suppress Adverse Outcomes With Early Implementation of the ACC/AHA Guidelines (CRUSADE) registries, Mexicans were younger than other Hispanics and non‐Hispanic white patients.21

Comorbidities

There is a wide variety of CVD risk factor profiles and comorbidities present in the heterogeneous US Hispanic population. In the Acute Coronary Treatment and Intervention Outcomes Network (ACTION) Registry‐GWTG study, Hispanic patients were more likely than non‐Hispanic white patients to have diabetes, but less likely to have had a previous MI or prior revascularization.20 Hispanic patients with STEMI from the New York State PCI Reporting System (NYS‐PCI‐RS) had higher rates of peripheral vascular disease and diabetes.22 Among patients presenting with NSTE ACS from the RENASICA–CRUSADE registries, Mexicans were more likely to be current smokers than other Hispanic or non‐Hispanic white patients, but had lower incidence of hypertension, hyperlipidemia, renal failure, or prior revascularization. Hispanics had a significantly higher incidence of diabetes than non‐Hispanic whites.21

In the Hispanic Community Health Study/Study of Latinos, the prevalence of hypercholesterolemia was 52% among men (ranging from 48% in Dominicans and Puerto Ricans, to 55% in Central Americans) and 37% in women (ranging from 31% in South Americans to 41% in Puerto Ricans). About 37% of men were obese (ranging from 27% in South Americans to 41% in Puerto Ricans), and 43% of women were obese (highest among Puerto Ricans). About 17% of men and women had diabetes mellitus, with prevalence ranging from 10% in South Americans to 19% in Mexicans and Puerto Rican women. About 26% of men were current smokers (highest among Puerto Ricans), and although relatively few women were current smokers (15%), 32% of Puerto Rican women and 21% of Cuban women were current smokers. After adjusting for age and sex, the prevalence of coronary heart disease (CHD) and stroke was significantly higher in the following groups: men, those ≥65 years of age, second‐ and third‐generation immigrants, and those who preferred English. The presence of ≥3 risk factors was highest among Puerto Ricans, and was significantly higher among those with less education and those who were either US born or had lived in the United States for 10 or more years.23

Higher education does not necessarily mean greater health; among Mexican Americans, more education is associated with higher odds of hypertension and larger waist circumference, regardless of birthplace. Among US‐born Mexican American women, the odds of diabetes also increased with education.24

The relationship between comorbidities, gender, and time spent living in the United States is also complex. Foreign‐born Mexican American women who had lived in the United States for 5 to 19 years had the highest risk of diabetes, whereas foreign‐born men who had lived in the United States for fewer than 5 years had the lowest odds of large waist circumference and diabetes.24

The relationship between hypertension and time spent living in the United States does not appear to be linear for Mexican‐born men; those in the United States for ≥20 years had the greatest chance of hypertension, those in the United States for 5 to 19 years had a 39% lower chance, and those who had been in the United States <5 years had only a 26% lower chance.24

In a study on CVD risk factor differences between first‐ and second‐generation Mexican Americans, men did not differ in Framingham Risk Score (FRS), total cholesterol, or diabetes rates. Second‐generation men were less likely to smoke than first‐generation men, but had lower high‐density lipoprotein (HDL) cholesterol levels and higher rates of hypertension. Neither FRS nor diabetes rates differed between first‐ and second‐generation women. Second‐generation women had higher rates of hypertension than first‐generation women, but had lower total cholesterol levels, higher levels of HDL cholesterol, and lower rates of smoking.25

Treatment and Medication

Hispanic patients on average experience longer delays in receiving drug or surgical treatments for MI/ACS, compared to non‐Hispanic white patients. In the ACTION Registry‐GWTG study, investigators found significant delays in triage and reperfusion in Hispanic patients compared to non‐Hispanic white patients.20 In a study on a large cohort of patients from the National Registry of Myocardial Infarction from 1999 to 2002, door‐to‐drug and door‐to‐balloon times were significantly longer for Hispanic patients than for white patients when receiving primary PCI for STEMI, although some of this disparity was attributed to treatment hospitals.12 In STEMI patients undergoing primary PCI as part of the GWTG study, median door‐to‐balloon times were marginally, but not significantly, longer for Hispanic patients than for non‐Hispanic white patients, and Hispanic ethnicity was not associated with reduced odds of door‐to‐balloon times ≤90 minutes (a quality‐of‐care indicator for treatment of STEMI).13

In the ACTION Registry‐GWTG study, use of acute medications and primary PCI was similar in Hispanic and non‐Hispanic patient groups,20 and Hispanic patients in the NYS‐PCI‐RS study were found to have higher rates of surgical or PCI revascularization.22 Other studies show lower rates of revascularization for Hispanic patients. In a study comparing revascularization with insurance status, Hispanics were overall 5% less likely than non‐Hispanic whites to receive revascularization after adjusting for patient demographics, comorbidities, and hospital clustering.16 There are indications that treatment is becoming more similar as time passes; in the QIOCDW‐CMMS study, disparities in same‐hospital treatment between Hispanic and non‐Hispanic white patients dropped significantly from 2005 to 2010.7

Outcomes

In the ACTION Registry‐GWTG study, the mean in‐hospital stay was longer for Hispanics than non‐Hispanic whites, but in‐hospital mortality did not differ significantly, even after adjusting for patient and hospital characteristics.20 Despite longer times to STEMI triage, reperfusion, and less use of evidence‐based discharge care, Hispanics and non‐Hispanic whites in this study had similar clinical outcomes.20 In the study of patients in the RENASICA‐CRUSADE registries, mortality outcomes were similar in Hispanics and non‐Hispanic whites.21 Similarly, in STEMI patients undergoing primary PCI as part of the GWTG study, investigators found no association between race/ethnicity and in‐hospital mortality.13 In the analysis of 12 555 AMI patients in New York City, Hispanics were more likely to survive than whites, and among patients who were not revascularized, Hispanics were more likely to survive and be discharged than whites.3

Having preexisting complications may worsen outcomes. In 1415 patients hospitalized for AMI in 2007 in San Juan, Puerto Rico, in‐hospital mortality increased with age.26 Hispanic patients with preexisting CHD admitted to a cardiovascular service line were more likely to be dead or rehospitalized by 1‐year postadmission than white patients.19

Disparities Among Asian Americans

Comorbidities

The prevalence of dyslipidemia among 169 430 primary care patients in Northern California (≥5 years of age) was compared between Asian Americans (Asian Indian, Chinese, Filipino, Japanese, Korean, and Vietnamese), Mexican Americans, blacks, and non‐Hispanic whites.27 Nearly every Asian subgroup had significantly lower mean body mass index BMI than whites (the exception was Filipino women), while Mexican Americans and blacks had higher mean BMI than whites. Filipino, Korean, Vietnamese, and black men were more likely than whites to have ever smoked, whereas Asian and Mexican American women were less likely to have ever smoked. Asian Indians, Filipinos, Japanese, Mexican Americans and blacks all had significantly higher rates of diabetes than whites. After adjusting for age, the investigators found that Filipino and Mexican American women were most likely among all groups to have either high levels of triglycerides or low‐density lipoprotein cholesterol. Asian Indian and Mexican American women had the highest prevalence of low HDL cholesterol levels; both groups had more than twice the prevalence found in Japanese women (23.7%). Mexican American women and all Asian subgroups except Korean women had a higher prevalence of high triglyceride levels compared to white patients, but black patients had the lowest prevalence of high triglyceride levels (18.1%). In general, the prevalence rates of all 3 dyslipidemia types were higher in men.27

Treatment

Concerning treatment delays, in the study of 73 032 patients from the National Registry of Myocardial Infarction, black patients had the longest door‐to‐drug time, followed by Asians/Pacific Islanders, and then by Hispanic patients; all had significantly longer door‐to‐drug times than non‐Hispanic white patients. Racial and ethnic differences remained significant after adjustment for mean times to treatment in the hospitals where patients were treated, and these differences persisted after further adjustment for sociodemographic characteristics, insurance status, and clinical and hospital characteristics.12

Outcomes

Data for in‐hospital mortality or death within 30 days of surgery were considered for 173 925 Medicare recipients ≥65 years of age who had CABG performed in 2007 and 2008. Investigators adjusted risk using patient characteristics such as age, sex, race, emergency admittance, and comorbidity; a socioeconomic status score that included measures of income, education, and profession; and a measure of relative hospital quality. In the unadjusted analysis, nonwhite patients had a 34% higher risk of death following CABG surgery. Hospitals treating the largest proportion of nonwhite patients had the highest risk‐adjusted mortality for both white and nonwhite patients, and, conversely, hospitals treating the smallest proportion of nonwhite patients had the lowest mortality for both white and nonwhite patients.28

Discussion

Table 1 and Table 2 summarize disparities in blacks and Hispanics, respectively, regarding ACS and MI. Table 3 describes studies that compare all 3 populations together—non‐Hispanic white, black and Hispanic. People in these minority groups are also more likely to live in poorer neighborhoods and, for a variety of reasons, may have poorer health habits that lead to comorbidities and worse outcomes. Residential location can also mean that care is delivered in less‐than‐optimal hospital settings. Several studies in this review found that hospital setting can have a major impact on the quality of treatments and outcomes.

Table 1.

Summary of Acute Coronary Syndrome– and Acute Myocardial Infarction–Related Disparities in Blacks

Demographics	Comorbidities	Health Risks
More likely than whites	More likely than whites	More likely than whites
Younger3, 4, 5, 6, 7, 31	Dyslipidemia2	Physical inactivity2
Female4, 5, 7, 31	Obesity2, 10	Current smoking2
Uninsured4, 5	Higher BMI6, 27	Current smoking (men >55)8
Insured by Medicaid4, 8	Hypertension2, 4, 5, 6, 8, 10	Tobacco use6
Less education/no education beyond high school6, 8	Insulin resistance2	History of smoking4, 5, 27
Low income6, 8	Hyperglycemia2	History of stroke5
Less likely than whites	Diabetes2, 4, 5, 6, 8, 10, 27, 31	Poor eating habits2
Private insurance5	Chronic kidney disease2	Less likely than whites
Cardiology care5	Renal insufficiency4, 5	Take prescribed cardiac medications (nonwhites)11
	CHF4, 5, 8
	Previous MI4
	History of gastrointestinal bleeding4
	Lower base hemoglobin4
	Multiple cardiovascular risk factors8, 10, 32
	Less likely than whites
	CHF3
	Previous AMI31
Delays	Treatments	Outcomes
Longer than whites	More likely than whites	More likely than whites
Door‐to‐drug times12	Prescribed aspirin5	Survive and be discharged (when not treated with revascularization)3
Door‐to‐balloon times12		Rehospitalization (nonwhites)11
More likely than whites	Less likely than whites	Recurrent AMI (nonwhites)11
Slower transfer to revascularization hospital14	Diagnostic cardiac catheterization5	Recurrent AMI (5 years post‐PCI)32
Less likely than whites	Catheterization31, 33	Rehospitalized for AMI (<1 year post‐AMI)18
Door‐to‐balloon times <90 minutes13	Non‐protocol mandated angiography (nonwhites)11	Death (nonwhites)11
Transfer to hospital with revascularization services15	Use of lidocaine6	Death following CABG (nonwhites)28
	PCI5, 7	Mortality (>30 days post‐AMI)15
	PCI or CABG within 3 months of AMI17	Mortality (5 years post‐PCI)32
	Revascularization (admitted to nonrevascularization hospital)15	Rehospitalization or death within 1 year post‐CHD hospitalization30
	Revascularization3, 16, 34	Adverse cardiac outcomes (1‐year post revascularization)35
	PTCA31	Shorter median survival times following CABG36
	CABG31, 33	CHF (5 years post‐PCI)32
	CABG (high‐risk patients)5	Symptoms and clinic visits (1 month post‐ACS)6
	Emergent CABG4	Symptoms (6 months post‐ACS)6
	Receive stent if undergoing PCI (nonwhites)11	Less likely than whites
	Stress test33	Procedural success with PCI (nonwhites)11
	Echocardiogram33	Mortality <30 days post‐AMI15
	Drug‐eluting stents4
	Prescribed prasugrel4
	Prescribed clopidogrel5
	Prescribed GP IIb/IIIa inhibitors5
	Less likely than whites or Hispanics
	Revascularization3

Abbreviations: ACS, acute coronary syndrome; AMI, acute myocardial infarction; BMI, body mass index; CABG, coronary artery bypass graft; CHD, coronary heart disease; CHF, congestive heart failure; GP, glycoprotein; MI, myocardial infarction; PCI, percutaneous coronary intervention; PTCA, percutaneous transluminal coronary angioplasty.

Table 2.

Summary of Acute Coronary Syndrome– and Acute Myocardial Infarction–Related Disparities in Hispanics

Demographics	Comorbidities	Health Risks
More likely than non‐Hispanic whites	More likely than non‐Hispanic whites	Less likely than non‐Hispanic whites
Younger3, 7, 20, 31	Hypertension 19	Take prescribed cardiac medications (nonwhites)11
Female31	Diabetes10, 19, 20, 21, 22, 31
Uninsured19, 20	Renal failure19
	Peripheral vascular disease22
	Less likely than non‐Hispanic whites
	Previous MI20, 31
	Prior revascularization20
Delays	Treatments	Outcomes
Longer than non‐Hispanic whites	More likely than non‐Hispanic whites	More likely than non‐Hispanic whites
Door‐to‐drug times12	Surgical or PCI revascularization22	Survive and be discharged (when not treated with revascularization)3
Door‐to‐balloon times12	Less likely than non‐Hispanic whites	Longer in‐hospital stay20
Time to triage20	Catheterization31, 33	Rehospitalization or death within 1 year post‐CHD hospitalization30
Time to reperfusion20	Non–protocol mandated angiography (nonwhites)11	Rehospitalization (nonwhites)11
	PTCA31, 33	Recurrent AMI (nonwhites)11
	CABG31	Death (nonwhites) 11
	Revascularization16, 34	Death following CABG (nonwhites)28
	Receive stent if undergoing PCI (nonwhites)11	Less likely than non‐Hispanic whites
		Use of evidence‐based discharge care20
		Procedural success with PCI (nonwhites)11

Abbreviations: AMI, acute myocardial infarction; CABG, coronary artery bypass graft; CHD, coronary heart disease; MI, myocardial infarction; PCI, percutaneous coronary intervention; PTCA, percutaneous transluminal coronary angioplasty.

Table 3.

Acute Coronary Syndrome– and Acute Myocardial Infarction–Related Mortality Outcomes in Studies Featuring Separate Black, Hispanic, and non‐Hispanic White Racial/Ethnic Groups

Study	Key Features	Outcome	Non‐Hispanic White, HR	Black, HR (95% CI)	Hispanic, HR (95% CI)
Sabatine et al11	TACTICS‐TIMI‐18 trial participants	Death, MI, or rehospitalization for ACS, within 6 months	1.00	1.39 (0.95‐2.03)	1.70 (1.18‐2.44)
	Presenting with: non–ST‐elevation ACS
	Adjusted for: age, sex, hospital type, cardiac risk factors, prior cardiac history, baseline cardiac medications, presenting ST deviation, and cardiac biomarkers
Rangrass et al28	Medicare beneficiaries between 2007 and 2008	In‐hospital death, or death within 30 days	1.00	1.32 (1.19‐1.46), adjusted for SES 1.16 (1.04‐1.29), adjusted for SES and HQ 1.13 (1.01‐1.27)	1.32 (1.10‐1.58), adjusted for SES 1.17 (0.96‐1.41), adjusted for SES and HQ 1.07 (0.88‐1.27)
	Undergoing: CABG procedure
	Adjusted for: age, sex, race, emergency admission, and comorbid conditions
Brown et al37	Medicare beneficiaries between 2007 and 2009	Death after discharge, within 1 year	1.00	1.38 (1.21‐1.57)	1.08 (0.79‐1.48)
	Presenting with: AMI
	Adjusted for: age
	Excludes patients with history of AMI, CHD, or revascularization

Abbreviations: ACS, acute coronary syndrome; AMI, acute myocardial infarction; CABG, coronary artery bypass graft; CHD, coronary heart disease; CI, confidence interval; HQ, hospital quality; HR, hazard ratio; MI, myocardial infarction; SES, socioeconomic status; TACTICS‐TIMI 18, Treat Angina With Aggrastat and Determine the Cost of Therapy With an Invasive or Conservative Strategy.

Associations between statin use and clinical outcomes were evaluated at 30 days and 1 year posthospitalization in a study of 3067 CHD patients who took part in the National Heart, Lung, and Blood Institute–sponsored Family Cardiac Caregiver Investigation to Evaluate Outcomes study.29 Blacks and Hispanics were less likely to report statin use before admission, but statin use after discharge was not significantly different. (In a different study, Hispanic patients with preexisting CHD were also less likely to report statin use before admission to a cardiovascular service line19) Rates of death and readmission at 30 days posthospitalization did not differ by race or ethnicity, and there was no association between preadmission statin use and death or readmission at 30 days. However, patients with a statin prescription at discharge were significantly less likely to be dead or readmitted at 30 days, independent of demographic characteristics or comorbidities. At 1‐year posthospitalization, blacks and Hispanics were more likely than white or Asian patients to be dead or to have been rehospitalized. This was not associated with statin prescription before or after hospitalization.30

Racial and ethnic gaps in treatment quality measures are narrowing, and when treatment guidelines are rigorously adhered to, all patients benefit regardless of their race or ethnicity. In a study on more than 2 million AMI hospitalizations, the adjusted racial and ethnic gap in performance rates among US hospitals on 17 process‐of‐care quality measures narrowed significantly for both black and Hispanic patients compared to white patients between 2005 and 2010. Despite this narrowing, the gap in PCI rates between blacks and whites in 2010 remained 3 times the size of the gap in PCI rates between Hispanics and whites.7

The causes underlying racial and ethnic differences in ACS/AMI are complex and are not rooted solely in the healthcare system and its providers; they extend to cultural norms, local community, and to patients' personal characteristics, preferences, hesitancies, trust level, education, finances, and transportation options. The interactions between these many factors and how they result in different outcomes are not always well defined. Solutions, accordingly, will be complex, confounding efforts that seek simple fixes. They will require sophisticated and nuanced approaches that consider people as much as they do systems.

Conclusion

Through many efforts over the years, care for ACS and MI has improved substantially in quality, benefiting all racial and ethnic groups, but disparities, even when successfully narrowed, persist. Continued research will be needed to further reduce and eliminate ACS/MI disparities, along with public health efforts focused on reducing health risks and their related comorbidities.