December 19, 2011

Pediatric heart transplants: Whites more likely to survive long term

White heart transplant patients under the age of 18 are more than twice as likely to be alive a decade after surgery as their African-American counterparts, new Johns Hopkins research suggests.

The findings, part of a large-scale review of factors that appear to significantly influence long-term survival among pediatric heart transplant patients, were presented Nov. 13 at the American Heart Association’s annual Scientific Sessions in Orlando, Fla.

“It’s unclear whether these racial disparities are due to biological differences or socioeconomic differences that have an impact on access to care, or some combination of the two,” said Arman Kilic, a surgical resident at The Johns Hopkins Hospital. “That’s been hotly debated, but these data tell us we need to do a lot more research to figure out why those disparities exist and how we can narrow the gap.”

Kilic analyzed United Network of Organ Sharing data from the 2,721 pediatric heart transplants performed in the United States between 1987 and 1999. Forty-two percent of patients (1,143) were alive 10 years or more after transplant. The average age of the recipients at the time of transplant was younger than 6.

In addition to racial disparities in long-term survival, the analysis showed that boys are 26 percent more likely than girls to survive a decade after their transplants; children who had their surgeries at hospitals where large numbers of transplants are done annually also were more likely to be alive 10 years later. For every 10 additional pediatric heart transplants conducted at a hospital each year, the chance of 10-year survival for patients transplanted there increased 36 percent. Patients at high-volume centers do better not only because their surgeons likely have more experience with heart transplants, Kilic said, but also because the staff and facilities are likely better equipped to manage the complex post-operative care of these patients.

The findings also show that patients transplanted later in the study period and those who got their hearts from younger donors were significantly more likely to survive long term. Those who were on mechanical ventilation prior to their transplant were less likely to live a decade than those who were breathing on their own before surgery.

“Children are potentially a group of patients whose survival after transplantation could be several decades, so it’s especially important to better understand why some do well and others do not,” Kilic said.