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Quality of hospitals where black patients seek care plays key role in racial differences in health care

ANN ARBOR, Mich. — Black patients having a heart attack wait longer at hospitals than white patients to get advanced procedures that will restore blood flow to their hearts, according to a University of Michigan Health System study.

The differences in care may be explained by hospital quality, rather than the race of individual patients. Black patients were much more likely to go to slow hospitals than were whites, and as a result waited six hours longer to get life-saving procedures.

Most elderly black patients received care in a small number of hospitals that take longer to transfer their patients, regardless of race, according to the U-M study published in the July issue of Medical Care, the journal of the American Public Health Association.

“These data suggest that an individual’s race may play much less of a role in generating differences in care, while the hospitals where black patients often go may be even more important,” says study lead author Colin R. Cooke, M.D., a Robert Wood Johnson Clinical Scholar at the University of Michigan.

Each year tens of thousands of patients with heart attacks use hospitals that lack staff and capacity to perform angioplasty or open heart surgery – commonly called revascularization procedures that open clogged arteries and restore blood flow to the heart.

Experts recommend that heart attack patients, who come to the emergency room of these hospitals, be transferred quickly to one that can do revascularization.

Researchers analyzed nearly 26,000 Medicare patient records for the study that looked at how hospitals across the nation may influence racial differences in health care.

The U-M authors note that the causes for delays in hospitals that serve a greater number of black patients is not clear, but based on prior research speculate that quality of care at these hospitals may be worse.

Strapped by financial constraints, safety net hospitals may forego development of a ‘quality improvement culture’ or limit adoption of computer order entry or electronic medical records, infrastruture which may improve the quality of care.

The most important step in improving cardiovascular care for black patients is addressing organizational issues and resources at hospitals where black patients seek medical care, authors say.

Additional authors: Brahmajee Nallamothu, M.D., M.P.H., John D. Birkmeyer, M.D. and Theodore J. Iwashyna, M.D., Ph.D., all of U-M and Jeremy M. Kahn, M.D., University of Pittsburgh.

Reference: “Race and Timeliness of Transfer of Revascularization in Patients with Acute Myocardial Infarction,” Medical Care.

Funding: Robert Wood Johnson Foundation Clinical Scholars Program, National Institutes of Health.

Resources:

University of Michigan Cardiovascular Center http://www.uofmhealth.org/medical-services/heart-and-vascular

U-M Division of Pulmonary and Critical Care Medicine http://www.med.umich.edu/intmed/pulmonary/

Written by Shantell M. Kirkendoll

PHILADELPHIA – Black cardiac arrest victims are more likely to die when they’re treated in hospitals that care for a large black population than when they’re brought to hospitals with a greater proportion of white patients, according to new research from the University of Pennsylvania School of Medicine. The study is published in the April issue of the American Heart Journal.

The Penn team found that, among 68,115 cardiac arrest admissions analyzed through Medicare records, only 31 percent of black patients treated in hospitals that care for a higher proportion of black patients survived to be discharged from the hospital, compared to 46 of those cared for in predominantly white hospitals. Results showed that even white patients were less likely to survive when treated at these hospitals which provide care for higher proportions of black patients.

“Our results also found that black patients were much more likely to be admitted to hospitals with low survival rates,” says lead author Raina M. Merchant, MD, MS, an assistant professor of Emergency Medicine. “Since cardiac arrest patients need help immediately and are brought to the nearest hospital, these findings appear to show geographic disparities in which minority patients have limited access to hospitals that have better arrest outcomes. For example, these hospitals may not utilize best practices in post-arrest care, such as therapeutic hypothermia and coronary artery stenting procedures. These findings have implications for patients of all races, since these same hospitals had poor survival rates across the board.”

Among factors that may influence the disparities, several include: differences in staff quality and training, patient/family preferences regarding end-of-life care and withdrawal of life support during the post-arrest period where prognosis is often uncertain, and variation in ancillary supports such as laboratory, cardiac testing or pharmacy services. Merchant and her colleagues suggest that further research into how the use of advanced postresuscitation therapies influence survival is necessary to improve outcomes for all patients, perhaps leading to the development of a regionalized care model for cardiac arrest, similar to the system that funnels trauma patients to hospitals that meet strict national standards.

Other authors of the study include Lance B. Becker, MD, Feifei Yang, MS, and Peter W. Groeneveld, MD, MS.

Tampa, FL (April 18, 2011) — Non-Hispanic black infants born with heart defects are more likely to die within the first five years of life than their non-Hispanic white and Hispanic peers. For certain types of congenital heart abnormalities, Hispanic children as well as non-Hispanic black children fare worse than non-Hispanic white children.

These findings, detailed in a new study by researchers at the University of South Florida, Texas Department of State Health Services and University of Texas Southwestern Medical Center, suggest preventive strategies are needed to reduce racial and ethnic disparities among infants and young children with heart defects. The research is published online today in the journal Pediatrics.

“When you consider that the numbers of minority children continue to grow and are expected to account for more than half of all U.S. children by 2040, it’s clear we need to reduce the racial and disparities that burden the health care system and adversely affect the lives of families,” said lead author Wendy Nembhard, PhD, associate professor of epidemiology at the USF College of Public Health.

Congenital heart defects are malformations in one or more structures of the heart or major blood vessels that occur before birth. They are the most common of all birth defects and the leading cause of death among infants with birth defects.

The new study adds to a growing body of evidence that minority infants with specific types of heart defects have poorer survival rates in early childhood than non-Hispanic white infants.

The researchers retrospectively reviewed the records of 19,530 single infants born with congenital heart defects in Texas from January 1996 through December 2005. The study was limited to infants born to non-Hispanic white, non-Hispanic black and Hispanic women. Linking records from the Texas Birth Defect Registry to Texas death records and the National Death Index, the researchers analyzed survival rates and risk of childhood death within the first five years of life for each type of congenital heart defect.

Among the study findings:

• Non-Hispanic black race/ethnicity was more strongly associated with increased risk of early childhood death than Hispanic race/ethnicity.
• Overall, non-Hispanic black infants with congenital heart defects had a 32 percent greater risk of early childhood death than their non-Hispanic white counterparts. In contrast, Hispanic infants with heart defects had no overall increased risk of early childhood death when compared with white infants.
• The risk of early childhood death was twice as great for non-Hispanic black infants with a reversal in primary connections of the heart’s two main blood vessels (known as transposition of the great arteries) as for similarly affected non-Hispanic white infants. The same two-fold increased risk was seen in this group for tetralogy of Fallot, a cyanotic heart defect causing low oxygen levels in the blood.
• Of the three racial/ethnic groups, non-Hispanic black infants consistently had the lowest survival rates for congenital abnormalities in the septum (wall) separating the left and right sides of the heart.
• Hispanic children had the lowest survival rate of the three groups for hypoplastic left heart syndrome, a rare defect in which the heart’s left side is critically underdeveloped. They were also less like to survive than non-Hispanic whites when born with pulmonary valve atresia without ventricular septic defect, a condition including absence of the pulmonary valve opening in the heart.

The researchers suggest the inequalities in early childhood survival may be caused by several factors: underlying racial/ethnic biological differences, including severity of the defect or the number of co-occurring defects; lack of timely access to quality health care; and cultural factors or preferences, such as differences in prenatal diagnosis of defects.

Future studies should determine what role these factors and others may play, so that effective public health policies can be devised to improve the health of minority children born with heart defects, the researchers conclude.

Publication citation:

Wendy N. Nembhard, PhD; Jason L. Salemi,MPH; Mary K. Ethen, MPH; David E. Fixler, MD, MSc; Angela DiMaggio, BS; and Mark A. Canfield, PhD; “Racial/Ethnic Disparities in Risk of Early Childhood Mortality Among Children With Congenital Heart Defects,” Pediatrics, published online April 18, 2011.

A team of scientists at Johns Hopkins and elsewhere has discovered that a single alteration in the genetic code of about a fourth of African-Americans helps protect them from coronary artery disease, the leading cause of death in Americans of all races.

Researchers found that a single DNA variation – having at least one so-called guanine nucleotide in a base pair instead of a combination without any guanine – on a gene already linked to higher risk of coronary disease in other races is linked in blacks to decreased risk. Specifically, the study showed that otherwise healthy African-American men and women with the alternative genetic code had a fivefold reduction in the likelihood that their arteries would narrow or clog.

For African-Americans who inherited two copies of the guanine gene variant, one from each parent, the risk reduction was even more dramatic. They were 10 times less likely to have coronary heart disease, which disproportionately afflicts a greater number of African-Americans than whites or any other ethnic group. Nearly 17 million Americans have an arterial problem plaguing the heart, causing a half-million deaths, annually.

“What we think we have here is the first confirmed hereditary link to cardiovascular disease among African-Americans and it is a protective one,” says senior study investigator and health epidemiologist Diane Becker, M.P.H., Sc.D. “This newly found link in African-Americans was not only protective instead of harmful but was also found at a precise location on gene CDKN2B, a gene close to the single base pair modification tied to other increased risk of coronary artery disease in other races.”

Becker emphasizes that only an estimated quarter of blacks have the protective CDKN2B code, and only 6 percent have two copies, so “while a lot of African-Americans have this protective genetic modification, most do not.” Advance testing for the genetic marker, she says, could ultimately in the future assist physicians in risk-stratifying those without inherited protection so they could be monitored more closely for early signs and symptoms of disease.

The findings are set to appear in the Journal of Human Genetics online Jan. 27.

Becker, a professor at both the Johns Hopkins University School of Medicine and Hopkins’ Bloomberg School of Public Health, and a team that included researchers at Duke and Emory universities, also say their results, based on blood analysis from 548 black men and women in the Baltimore region and confirmed in several hundred more in the Atlanta and Durham, N.C., regions, help explain why earlier studies found potentially dangerous genetic connections to this type of heart disease in Caucasians, Hispanics and Asians, but failed to find a negative tie-in to the disease in blacks.

Earlier studies, says Becker, had involved genome-wide reviews in multiracial populations and taken “a needle in the haystack approach” to finding that one change in a string of some 58,000 base pairs, in a chromosomal region known as 9p21. That region, which includes CDKN2B, is associated with higher rates of coronary disease in non-blacks.

The team’s latest analysis was successful, she believes, because it had a large and sufficiently broadly based black volunteer population. The study group comprised men and women between the ages of 26 and 60. Investigators also focused on the 9p21 region and a subsection of genetic material within called ANRIL that overlaps and is closely held to CDKN2B, but away from the deleterious genetic variant found earlier.

Johns Hopkins cardiologist Brian Kral, M.D., M.P.H., says the abundance of activity in this particular region of the genome, including CDK2NB and ANRIL, suggests that everyday replication of this zone could play a more fundamental, underlying role in the progression of coronary artery disease in all races.

Kral, an assistant professor at Johns Hopkins and its Heart and Vascular Institute. was co-lead investigator of the latest study, along with Hopkins genetic epidemiologist Rasika Mathias, Sc.D. The team next plans to further investigate the ANRIL subregion of 9p21 to see if any single genetic changes speed up or slow down progression of coronary diseases.

Blood samples for the genetic analysis came from a larger study being led by Becker of some 4,000 people from white and African-American ethnic backgrounds. Called the Genetic Study of Atherosclerosis Risk (GeneSTAR), under way at Johns Hopkins since 1983, it involves participants who were all healthy upon enrollment, with no existing symptoms of heart disease. All were monitored for at least five years with periodic check-ups to see who developed heart disease and who did not. Each had a sibling or a parent who had a history of coronary artery disease or some other symptom of blocked arteries, such as chest pain or shortness of breath. The latest study was based on results collected through 2007, by which time 35 black study participants had suffered some form of heart attack or needed an angioplasty or X-ray scan of the heart’s blood vessels to confirm or rule out arterial blockages.

Study funding was provided by the National Heart, Lung and Blood Institute (NHLBI), a member of the National Institutes of Health, and the Johns Hopkins Clinical Research Center.

In addition to Becker, Kral and Mathias, other Hopkins researchers involved in this report are Bhoom Suktitipar, M.D.; Ingo Ruczinski, Ph.D.; Dhananjay “Jay” Vaidya, M.B.B.S., Ph.D.; Lisa Yanek, M.P.H.; and Lewis Becker, M.D. Arshed Quyyumi, M.D.; Riyaz Patel, M.D.; A Maziar Zafari, M.D., Ph.D.; and Viola Vaccarino, M.D., Ph.D., all at Emory University in Atlanta, also contributed to the research. Further study assistance and support was provided from Elizabeth Hauser, Ph.D., and William Kraus, M.D., both at Duke University Medical Center in Durham, N.C.