Curr Cardiovasc Risk Rep DOI 10.1007/s12170-013-0331-z

RACE AND ETHNICITY DISPARITIES (M ALBERT, SECTION EDITOR)

Meeting Disparities Where they Reside: The Geography of Racial and Ethnic Health Disparities in Cardiovascular Health Melissa Burroughs Peña

# Springer Science+Business Media New York 2013

Abstract Despite the Institute of Medicine report on racial and ethnic disparities in health care outcomes that was published more than 10 years ago, disparities in health outcomes including cardiovascular disease outcomes persist. The recent literature on racial and ethnic disparities in cardiovascular disease outcomes incorporates geospatial-mapping analyses in order to shed light on the ways in which disparities vary by location, highlighting variability in access to health care. In addition the problem of access to health care, the quality of the health care that is available to minority communities has also been scrutinized, underscoring the potential of quality improvement interventions to reduce existing disparities in cardiovascular outcomes. Targeted interventions to expand health education, expand access to primary and tertiary care and improve the quality of the health care received by racial and ethnic minorities could reduce disparities in cardiovascular outcomes. Keywords Cardiovascular disease . Health status disparities . Residence characteristics . Quality improvement

Introduction Racial and ethnic disparities in health outcomes have been described for decades culminating in the 2002 Institute of Medicine report Unequal Treatment: Confronting Racial and Ethnic Disparities in Health Care [1••]. Racial disparities in cardiovascular disease risk factors, prevalence and outcomes have been highlighted and contribute to the significantly lower life expectancy of African Americans in comparison

M. Burroughs Peña (*) Division of Cardiology, Department of Medicine, Duke University Medical Center, Duke Clinical Research Institute, Duke Global Health Institute, 2301 Erwin Rd, Durham, NC 27712, USA e-mail: [email protected]

to White Americans [2, 3]. However, much of the literature describing racial and ethnic disparities in cardiovascular disease generates hypotheses about mechanisms for health disparities rather than informing potential interventions and policies to reduce health disparities. In the setting of the current political and economic climate in which the full implementation of the Affordable Care Act is on the horizon, there is an urgent need for translational research in racial and ethnic health disparities that can directly influence health care systems and policy. The recent cardiovascular health disparities literature has taken an important step by incorporating geospatial-mapping and neighborhood analyses in disparities research. While narrowing the focus to identifying the geographical spaces in which racial and ethnic disparities in cardiovascular health reside, these recent studies have also examined disparities in cardiovascular outcomes beyond coronary artery disease and heart failure. These publications underscore the fact that racial and ethnic identity derive meaning in the context of social, political and economic environments, and as these environments vary, so does the relationship between race, ethnicity and health. This review explores the cardiovascular literature and examines the geography-related aspects of disparities research in a manner that has the potential to impact local, state and federal health policy.

Examples of Cardiovascular Health Disparities by State and County Rather than focusing primarily on racial and ethnic disparities in aggregate, increasingly racial disparities in cardiovascular care and outcomes are being explored at the state and county level. For example, Gebreab and Diez Roux looked at BlackWhite difference in coronary heart disease mortality by county using the Centers for Disease Control and Prevention’s WONDER database [4••]. They utilized geographically-weighted

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regression modeling to explore spatial heterogeneity, thus allowing the relationship of predictor variables and outcomes to differ across space. These authors found that before controlling for poverty and segregation there was large variability in the Black-White difference in CHD mortality across counties. Whereas in certain counties African Americans demonstrated higher observed CHD mortality rates when compared to White Americans, other counties demonstrated no racial disparity or higher CHD mortality in White Americans in comparison to African Americans. Higher CHD mortality was noted in the West South Central, Mississippi-Ohio River, West Coast and South Florida regions. However, adjustment for poverty and segregation eliminated the observed CHD mortality disparity. Moreover, the interaction between race, poverty, segregation and CHD mortality varied. Poverty was differentially associated with larger CHD mortality among White Americans, while segregation impacted CHD mortality to a greater degree in African Americans. For African Americans, segregation was associated with higher CHD mortality in some counties and lower CHD mortality in other counties. The authors speculated that segregation potentially restricts access to resources but might also increase social support, thus impacting different communities in different ways. This study highlights the complexity of racial and ethnic disparities in their interaction with county-specific variables. Notwithstanding CHD mortality rates, peripheral artery disease is an understudied topic in cardiovascular racial and ethnic disparities [5]. Jones et al. examined the rates of lowerextremity amputation for peripheral artery disease by year and state using data from the Centers for Medicaid and Medicare Services [6]. While the overall rate of lower-extremity amputation for peripheral artery disease decreased from 2000 to 2008, significant racial and geographical disparities were uncovered. After adjusting for covariates, African Americans were 2.9 times more likely to undergo lower-extremity amputation when compared to White Americans (p<0.001). This odds ratio is greater than that for the correlation between diabetes mellitus and amputation (OR=2.4, p<0.001). Interestingly, the highest rates of lower-extremity amputation were found in the East South Central, West South Central and South Atlantic regions, which are regions with relatively large African American populations. Unmeasured variables including socioeconomic status, access to care beyond insurance status and quality of available health care services were identified as potential explanations for the geographical variability, all variables that potentially contribute to the detected racial disparity.

Examples of Cardiovascular Disparities by Neighborhood Focusing the lens of racial and ethnic disparities beyond the county level, neighborhood analyses of cardiovascular risk factors and outcomes have provided additional depth to the

health disparities literature. An analysis from the Jackson Heart Study found that independent of individual socioeconomic status and health behaviors, neighborhood socioeconomic disadvantage was associated with the metabolic syndrome in African American women [7]. Two studies from the Atherosclerosis Risk in Communities (ARIC) community surveillance have examined both coronary revascularization and mortality after myocardial infarction by neighborhood income level [8, 9]. After adjusting for covariates including hospital type and comorbidities, African Americans in lowand medium-income communities were less likely to receive coronary angiography in the setting of myocardial infarction in comparison to White Americans in high-income communities with associated adjusted prevalence ratios (PR) of 0.73 and 0.83 respectively. By contrast, White Americans residing in low- and medium-income communities did not have statistically significant differences in coronary angiography in comparison to White Americans in high-income communities. Moreover, after receiving coronary angiography, African Americans in low- and middle-income communities were less likely to receive coronary revascularization. Within the same cohort, long- and short-term case fatality after myocardial infarction was higher for African Americans living in lowincome neighborhoods compared to White Americans living in high-income neighborhoods with adjusted odds ratios of 2.07 and 2.82 respectively after adjusting for age, sex and comorbidities [9]. Interestingly, African Americans in middleincome communities also had higher odds of long-term case fatality but no difference on short-term case fatality when compared White Americans in high-income communities; only White Americans in low-income neighborhoods had increased short-term case fatality, albeit they had no increase in long-term case fatality. The authors proposed that unmeasured health environmental variables might account for the disparity, as previous studies have found that neighborhood income level is associated with post-myocardial infarction mortality even after considering individual income status [10–12]. In examining the effect of race and neighborhood income on mortality after coronary artery bypass grafting and/or heart valve surgery, data from a single center found that neighborhood income level rather than race correlated with increased mortality [13]. Despite the inconsistent associations between race and neighborhood socioeconomic status, the literature suggest that health interventions targeted to higher risk communities have the potential to reduce both socioeconomic and racial disparities in cardiovascular health outcomes. At the neighborhood level, another area where staggering racial and ethnic disparities have been identified pertains to the delivery of bystander CPR after cardiac arrest. Utilizing data from the Cardiac Arrest Registry to Enhance Survival data from 29 sites in the United States, Sasson et al. examined neighborhoods according to income and racial composition in

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order to compare the rates of bystander-initiated CPR for cardiac arrest [14••]. In this work, income and neighborhood racial composition correlated with the probability of receiving bystander-initiated CPR for cardiac arrest, with African American low-income communities having the lowest rates of bystander initiated CPR. High-income African American communities still had substantially lower rates of bystanderinitiated CPR than non-African American high-income communities. Targeting CPR training in these communities was suggested as a potential public health intervention to reduce racial, ethnic and socioeconomic disparities in survival after cardiac arrest. Importantly, regardless of residence African and Latino Americans were 30% less likely to receive bystander-initiated CPR than White Americans.

Examples of Quality of Care and Cardiovascular Disparities Variability in the quality of care received by racial and ethnic minorities in the United States is also related to the medical facilities in which they receive care. In an analysis of Medicare beneficiaries presenting with acute myocardial infarction (AMI), after controlling for residential distance from the facility African Americans were more likely to be admitted to low-quality hospitals, teaching hospitals, safety-net hospitals and were less likely to be admitted to high-quality hospitals and hospitals with revascularization capability [15]. Moreover, African Americans and Asian/Pacific Islanders are more likely to undergo coronary artery bypass grafting by surgeons with higher risk-adjusted mortality rates [16], a factor in part explained by hospital characteristics, neighborhood income level and low volume surgeons. Interventions to improve the quality of cardiovascular care for all patients have the potential to decrease racial and ethnic health disparities in clinical outcomes. In the Get With the Guidelines- Coronary Artery Disease program, the quality of care of 142,593 patients with AMI in 443 hospitals was examined [17•]. Quality improvement interventions increased the use of evidence-based medications for the treatment of AMI over the 5-year study period for the entire patient population. Moreover, the disparity in the receipt of evidence-based therapies that existed between White American AMI patients in comparison to African American and Hispanic American AMI patients in the beginning of the study period decreased to the point of losing statistical significance. This improvement in AMI care was similar in hospitals that cared for disproportionately more African Americans and Latino Americans when compared to hospitals lower percentages of African American and Latino AMI patients. This analysis suggests that efforts to standardize AMI care might serve to reduce variability in medical treatment received for AMI, thus reducing racial and ethnic disparities in AMI treatment.

Similar to AMI care, in the Get With the Guidelines- Heart Failure program, quality improvement interventions were undertaken to improve the use of evidenced-based therapy for patients with heart failure. In examining ICD implantation for the prevention of sudden cardiac death, the increase in ICD use was greatest among African Americans to the point that the previously described disparity in ICD implantation in African Americans in comparison to White Americans was no longer present at the end of the study period [18]. Despite careful selection of patients for cardiac transplantation, racial disparities in survival have persisted while survival for the overall cardiac transplant population continues to improve [19]. Longitudinal data from the Organ Procurement and Transplantation Network (OPTN) database reveal survival differences by race. From 1987 to 2008, survival in the first 6 months after transplant improved for White American, African American and Hispanic American patients throughout the study period, yet African Americans remain at higher risk of death in the first 6 months when compared to White Americans. However, survival after 6 months improved for White American patients but not for African American and Hispanic American patients. The risk of death or retransplantation 6 months after cardiac transplantation is 111% higher African Americans when compared to White Americans. The authors postulate that the both immunologic and socioeconomic variables likely account for the racial disparity in transplant outcomes.

Conclusion Acknowledging that the causes of racial disparities in cardiovascular disease outcomes are complex and multifactorial, improving access to care and quality of care will potentially reduce racial disparities. Access to medical care in the United States does begin with obtaining health insurance. However, the attainment of health insurance represents one link in a chain of processes that should be aimed at eliminating health disparities by race and ethnicity. Other barriers that must be addressed include early and sustained access to quality health education, primary care and tertiary care centers. Through analyses that include geospatial mapping, health systems and policy makers are becoming equipped with the ability to target interventions to specific areas. Future work should examine the value of combining resources for quality improvement and disparities research. Compliance with Ethics Guidelines Conflict of Interest Melissa Burroughs Peña declares no conflict of interest. Human and Animal Rights and Informed Consent This article does not contain any studies with human or animal subjects performed by any of the authors.

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References Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance 1. •• Nelson A. Unequal treatment: confronting racial and ethnic disparities in health care. J Nat Med Assoc. 2002;94:666–8. 2. Wong MD, Shapiro MF, Boscardin WJ, Ettner SL. Contribution of major diseases to disparities in mortality. New Engl J Med. 2002;347:1585–92. 3. Harper S, Lynch J, Burris S, Davey SG. Trends in the black-white life expectancy gap in the United States, 1983–2003. JAMA. 2007;297: 1224–32. 4. •• Gebreab SY, Diez Roux AV. Exploring racial disparities in CHD mortality between blacks and whites across the United States: a geographically weighted regression approach. Health Place. 2012;18:1006–14. 5. Goodney PP, Travis LL, Nallamothu BK, et al. Variation in the use of lower extremity vascular procedures for critical limb ischemia. Circ Cardiovasc Qual Outcomes. 2012;5:94–102. 6. Jones WS, Patel MR, Dai D, et al. Temporal trends and geographic variation of lower-extremity amputation in patients with peripheral artery disease: results from U.S. Medicare 2000–2008. J Am Coll Cardiol. 2012;60:2230–6. 7. Clark CR, Ommerborn MJ, Hickson DA, et al. Neighborhood disadvantage, neighborhood safety and cardiometabolic risk factors in african americans: biosocial associations in the jackson heart study. PloS one. 2013;8:e63254. 8. Rose KM, Foraker RE, Heiss G, Rosamond WD, Suchindran CM, Whitsel EA. Neighborhood socioeconomic and racial disparities in angiography and coronary revascularization: the ARIC surveillance study. Ann Epidemiol. 2012;22:623–9. 9. Foraker RE, Patel MD, Whitsel EA, Suchindran CM, Heiss G, Rose KM. Neighborhood socioeconomic disparities and 1-year case

10.

11.

12.

13.

14.

15.

16.

17.

18.

19.

fatality after incident myocardial infarction: the Atherosclerosis Risk in Communities (ARIC) Community Surveillance (1992–2002). Am Heart J. 2013;165:102–7. Winkleby M, Sundquist K, Cubbin C. Inequities in CHD incidence and case fatality by neighborhood deprivation. Am J Prevent Med. 2007;32:97–106. Chaix B, Rosvall M, Merlo J. Neighborhood socioeconomic deprivation and residential instability: effects on incidence of ischemic heart disease and survival after myocardial infarction. Epidemiology. 2007;18:104–11. Wen M, Christakis NA. Neighborhood effects on posthospitalization mortality: a population-based cohort study of the elderly in Chicago. Health Serv Res. 2005;40:1108–27. Koch CG, Li L, Kaplan GA, et al. Socioeconomic position, not race, is linked to death after cardiac surgery. Circ Cardiovasc Qual Outcomes. 2010;3:267–76. •• Sasson C, Magid DJ, Chan P, et al. Association of neighborhood characteristics with bystander-initiated CPR. New Engl J Med. 2012;367:1607–15. Popescu I, Cram P, Vaughan-Sarrazin MS. Differences in admitting hospital characteristics for black and white Medicare beneficiaries with acute myocardial infarction. Circulation. 2011;123:2710–6. Rothenberg BM, Pearson T, Zwanziger J, Mukamel D. Explaining disparities in access to high-quality cardiac surgeons. Ann Thoracic Surgery. 2004;78:18–24. discussion −5. • Cohen MG, Fonarow GC, Peterson ED, et al. Racial and ethnic differences in the treatment of acute myocardial infarction: findings from the Get With the Guidelines-Coronary Artery Disease program. Circulation. 2010;121:2294–301. Al-Khatib SM, Hellkamp AS, Hernandez AF, et al. Trends in use of implantable cardioverter-defibrillator therapy among patients hospitalized for heart failure: have the previously observed sex and racial disparities changed over time? Circulation. 2012;125:1094–101. Singh TP, Almond C, Givertz MM, Piercey G, Gauvreau K. Improved survival in heart transplant recipients in the United States: racial differences in era effect. Circ Heart Fail. 2011;4:153–60.