Updated

Hispanic patients in need of a heart transplant are 50 percent more likely to die before they get one than white patients, according to new research.

And although that wasn't the case for black transplant patients in the study, the results suggest they have a higher chance of dying soon after they've received a donor heart than whites.

"All of us have recognized that ethnicity and race play a role in outcomes," said Dr. Ashish Shah, a transplant surgeon at Johns Hopkins Hospital in Baltimore, who was not involved in this research.

What's actually causing the disparities, however, is less clear, he said.

Previous studies have also found black patients fare poorly after transplants compared to whites (see Reuters Health report of May 4, 2011).

But less was known about how different racial groups do while they are waiting for a donor organ.

Researchers led by Dr. Tajinder Singh from Boston Children's Hospital gathered recent data from the U.S. Organ Procurement and Transplantation Network, which maintains the wait list for patients needing an organ.

More than 10,000 people were added to the list to receive a heart between July 2006 and September 2010.

Singh's group found 10.5 percent of white patients who were listed died during the study period or were taken off the list because they were too sick to receive a donor heart.

In comparison, 11.6 percent of black patients and 13.4 percent of Hispanic patients died or were removed from the list.

Black and Hispanic patients tended to be sicker by the time they were placed on the wait list, according to the study published in the journal Circulation.

For instance, 69 percent of black patients and 65 percent of Hispanics were considered to be of the highest urgency for a transplant, compared to 54 percent of white patients.

When the researchers took into account how sick people were, they found Hispanics were 51 percent more likely to die on the wait list than whites.

Health insurance, education levels and income can also make a difference in people's health and chance of dying -- and Singh's group tried to factor these in as well.

Still, researchers said it's possible to miss important factors that might explain the differences between patients, including certain other measures of sickness.

"Little differences may add up to somebody having a greater chance of dying while waiting," Shah told Reuters Health.

If it is the case that Hispanic patients who are just as sick as white patients are still more likely to die on the wait list, "then something else must be going on," said Shah. For example, "Are therapies in particular racial groups less effective?"

Although blacks were as likely as whites to survive while waiting for an organ, after the transplant they were more likely to die in the hospital.

Among more than 6,000 patients who received a heart, 5.4 percent of white patients, 5.9 percent of black patients and 3.9 percent of Hispanic patients died in the hospital.

After accounting for level of sickness and other risk factors, Singh's team concluded blacks were 53 percent more likely to die shortly after a heart transplant than whites.

Hispanics and whites had about equal risk.

Shah said the results of the study will be useful to help transplant centers examine their own performance. If centers find certain patient groups are not doing as well, they could look to those centers that are doing a better job and try to mimic their practices.

Hospital self-reflection is important in eliminating racial disparities among transplant patients, Singh agreed.

"The knowledge of disparity is usually the first step in ultimately getting rid of it," he said.