(Reuters Health) - - Black and Hispanic patients who need kidney transplants are less likely than white people to receive organs from live donors and this disparity has worsened over time, a U.S. study suggests.

After two years of waiting for a kidney, 11.4 percent of white patients received an organ from a live donor in 2014, almost four times the proportion of black patients, researchers report in JAMA. Two decades earlier, 7 percent of white patients got kidneys from live donors, which was roughly twice the proportion among black people.

Over the 20-year study period, the proportion of black patients getting live kidneys fell from 3.4 percent to 2.9 percent.

During the same period, the proportion of Hispanic patients getting kidneys from live donors also declined, from 6.8 percent to 5.9 percent. Among Asian kidney recipients, however, live donation became more common, rising from 5.1 percent to 5.6 percent of patients.

“We know that live-donor kidney transplants that involve patients receiving a kidney from a living relative, friend or other altruistic person are associated with longer life expectancy and higher quality of life as compared with deceased donor kidney transplants or long-term dialysis treatment,” said lead study author Tanjala Purnell, a researcher at Johns Hopkins University in Baltimore.

While U.S. patients from racial and ethnic minority groups have long been less likely than white people to receive kidneys from live donors, the widening gap found in the study was a shock, Purnell said by email.

While the study didn’t examine why this disparity persists, it’s possible some of the problem may be explained by racial and ethnic minorities having less access to private health insurance, primary care providers and kidney specialists as well as language barriers or cultural or religious concerns about donation, Purnell said.

“It is important for patients to have early conversations about the benefits and risks of live-donor kidney transplantation with their doctors and family members,” Purnell added. “These conversations may be important for alleviating concerns about transplantation and donation.”

Shifts in organ donation policies and patient outreach in recent years have helped to increase the proportion of minority patients receiving kidneys from deceased donors, but haven’t had the same impact on live donation.

For the study, researchers examined data on 453,162 adults awaiting kidney transplants from 1995 to 2014.

Patients were typically around 51 years old and most were male. Almost half of them were white, although 30 percent were black, 16 percent were Hispanic and 6 percent were Asian.

Overall, 39,509 patients received live-donor kidney transplants within two years of joining the wait list, the study found.

Compared to white patients, black patients were 73 percent less likely to receive live kidney donations by the end of the study, while Hispanic patients had 48 percent lower odds and Asian patients had 58 percent lower odds.

At the beginning of the study period, black patients had been 55 percent less likely than white patients to receive a live-donor organ, Hispanic patients had been 17 percent less likely and Asian patients 46 percent less likely.

The study wasn’t a controlled experiment designed to prove whether or how race and ethnicity might influence the chances of receiving a kidney transplant from a live donor, or why disparities have increased over time. Researchers also couldn’t account for factors like income that might influence these odds.

At least some of the disparities revealed in the study may represent differences in how easily donors can afford to help, said Dr. Francisco Cigarroa, co-author of an accompanying editorial and a researcher at the University of Texas Health San Antonio. Patients with higher income, paid time off from work and more comprehensive medical benefits might have an easier time being live donors.

“Living donation rates among Black and Hispanic patients seem to be limited by clustering of medical risk factors such as obesity and diabetes which are linked to kidney disease, reduced access and education regarding transplant options among Black and Hispanic patients, and financial disincentives faced by donors related to lost wages and fear of losing employment secondary to time needed for recovery,” Cigarroa said by email.

“Additionally, as we set forth in our editorial, evidence has been provided that these factors are related to the socioeconomic status of the patient and donor as much or more than they are genetic differences related to race and ethnicity,” Cigarroa added.

SOURCES: bit.ly/2lWWDvJ and bit.ly/2qoOGUD JAMA, online January 2, 2018.