Study highlights:
• Children from lower socioeconomic neighborhoods are twice as likely to die or need another heart transplant than those from a higher socioeconomic status.
• Minority children were also more likely to die or need another heart transplant compared to white children.

DALLAS, April 7, 2009 — Children from lower socioeconomic neighborhoods who had a heart transplant were more likely than those of a higher socioeconomic status to die or need another heart transplant, researchers report in Circulation: Heart Failure.

“The new finding is the first time that low socioeconomic position has been associated with a higher risk of graft failure defined in this study as either death or needing a second transplant after a first heart transplant,” said Tajinder P. Singh, M.D., lead author of the study and a transplant cardiologist at Children’s Hospital Boston and Harvard Medical School.

Researchers analyzed 135 patients — 58 percent boys, median age 8.4 years — who received their first heart transplant at Children’s Hospital Boston between 1991–2005. Among them, 110 were white (82 percent) and 18 percent non-white (10 black; eight Hispanic; and seven from other racial groups).

Researchers compared 45 children in the lowest socioeconomic group to the remaining two-thirds (controls). The two groups were similar in age, gender, diagnosis and year of transplant. Overall, 40 children died and six underwent a re-transplant during the study period. Nine of these deaths occurred during the initial hospitalization for heart transplant. Among those who survived the initial hospital stay, during a median follow-up period of six years, 31 deaths and six re-transplants occurred.

Researchers found:
 

• Children from low socioeconomic neighborhoods were 2.4 times more likely to have graft failure after transplant when compared to the controls.
• Minority children were 2.7 times more likely to suffer graft failure when compared to whites.
• Among 9 early deaths during transplant hospitalization, 6 deaths, or 13.3 percent, occurred in the lower socioeconomic group compared to three deaths, or 3.3 percent, in the higher socioeconomic group.
• Survival of the transplanted heart was significantly shorter in the low socioeconomic group at one year, three years, and five years post-transplantation.

The time to death or re-transplantation was significantly shorter for children who came from a lower socioeconomic group. These children also had a higher likelihood of rejection in their transplanted hearts, researchers said.

“Low socioeconomic status and non-white race appear to be independent risk factors for worse outcomes,” said Singh, who is also assistant professor of pediatrics at Harvard Medical School.
Singh said low socioeconomic children may have been sicker when they came to the heart transplant center. “They also may have difficulty using available resources from the medical community, which may reflect the lack of resources available to them at a personal and family level.”

All patients in the study had medical insurance, had access to medical personnel and availability of medications during their clinical course, researchers said.

The researchers used a sophisticated statistical technique to analyze six different socioeconomic factors, a previously validated way to look at neighborhood socioeconomic data but new for transplant population. They used U.S. Census data to focus on block groups, the neighborhood of a person’s residence, and the smallest geographic census unit for which socioeconomic data is available. The six components were combined into a single score.

Lower socioeconomic status reflected:
• lower median income;
• lower median value of housing;
• fewer adults with high-school and college education;
• fewer adults in managerial, professional or executive positions; and
• fewer households with rental, interest or dividends as the source of their income.

These results should be considered preliminary and need to be confirmed in larger population groups, Singh said.

“Improving the outcomes of heart transplantation in the lower socioeconomic status children requires new strategies and interventions for patients, families and the medical system,” Singh said.

Co-authors are: Kimberlee Gauvreau, Sc.D.; Heather J. Bastardi, P.N.P.; Elizabeth D. Blume, M.D.; and John E. Mayer, M.D. Individual author disclosures are available on the manuscript.

###

Editor’s Note: The American Heart Association’s online cardiovascular wellness center – www.heart360.org – helps patients take control of their heart health by tracking blood pressure, cholesterol, glucose and other heart disease risk factors. 

Statements and conclusions of study authors that are published in American Heart Association scientific journals are solely those of the study authors and do not necessarily reflect the association’s policy or position. The association makes no representation or guarantee as to their accuracy or reliability. The association receives funding primarily from individuals; foundations and corporations (including pharmaceutical, device manufacturers and other companies) also make donations and fund specific association programs and events. The association has strict policies to prevent these relationships from influencing the science content. Revenues from pharmaceutical and device corporations are available at www.americanheart.org/corporatefunding.

NR09 – 1042 (Circ HF/Singh)