At the end of life, Black kidney disease patients are more likely than White patients to continue intensive dialysis instead of choosing hospice care, according to a new study.

Researchers also found that racial differences in kidney disease treatments became more extreme in the highest Medicare spending regions of the U.S.

“Racial differences exist; when you add the component of geography, those racial differences widen,” said study author Dr. Bernadette Thomas, senior clinical research nephrology fellow at the University of Washington in Seattle.

Racial differences in American healthcare are well documented–large disparities in rates of leg amputation as a result of poor circulation are one recently reported example.

Prior research shows that the reasons can be complex, and may include factors ranging from patients’ cultural preferences to providers’ practice standards, as well as financial or physical access to high-quality healthcare resources.

The current study, which looked at Black and White dialysis patients, found that whether a kidney disease patient moves from dialysis to hospice near the end of life is affected not only by race, but also geography.

Researchers analyzed records for nearly 101,000 patients from the national kidney registry who started dialysis or had a kidney transplant and died within four years of those events.

White patients were twice as likely as Black patients to stop dialysis (32 percent versus 16 percent), an important indicator that treatment was moving toward less intensive care.

Black patients were also half as likely to be referred to hospice care, according to the findings published in the Clinical Journal of the American Society of Nephrology.

But location also made a difference. Black patients in U.S. regions that spent the least amount on end-of-life treatments were twice as likely to be referred to hospice as Blacks living in high-spending regions (24 percent versus 12 percent) and nearly three times as likely to elect to end life-saving dialysis (27 percent versus 11 percent).

Those patterns may reflect more aggressive healthcare in general in high Medicare spending regions or it could result from patient preferences, Thomas said.

Urban regions with large hospitals tend to have the highest end-of-life Medicare spending, according to data from the Dartmouth Atlas of Health Care, which maps out healthcare spending patterns across the U.S.

According to Dr. Thomas, “There are clear differences between the choices that Black and White patients make at end of life. Black patients seem to make choices more consistent with more aggressive care at end-of-life when compared to White patients. The degree of these differences in choices seems to relate to where Black and White patients live in the country. Possible explanations for these findings likely relate to patient preferences based on cultural beliefs, as well as regional medical practices.”

Experts also noted that higher spending doesn’t mean patients are getting the best care, but could reflect treatment intensity.

“This study, because it’s using medical data rather than actually interviewing the patients themselves, doesn’t tell us whether the obstacle is coming from the side of the doctor or the patient,” said Deborah Carr, sociology professor in the Institute for Health, Health Care Policy & Aging Research at Rutgers University, who studies the issue. “On average Blacks compared to Whites have a greater desire for treatments,” Carr told Reuters Health.

Black patients are not part of a growing movement in favor of hospice and palliative care at the end of life instead of maintaining costly treatments associated with a poorer quality death, said Carr, who was not involved in the current study.

Researchers agreed that some Black-White disparities in treatments also stem from socioeconomic differences.

Black patients are less likely to have a living will, for example, Carr said, so the default decision for physicians tends to be to continue treatment.

Carr has found evidence that religion also plays a role. In separate studies, she told Reuters Health, the Black patients interviewed were more likely to say that God decides when they die, so the doctor should not choose palliative care because it would interrupt God’s plan.

“Where does the opposition come from regarding hospice? Is it that the patients are not requesting it or the doctors are not offering it? That’s a really important puzzle,” Carr said.

Blacks not only fare more poorly at the end of their lives, they have a higher probability of getting kidney disease to begin with and of receiving inadequate treatment, noted Rachel Patzer, assistant professor of transplantation surgery at Emory University School of Medicine in Atlanta.

Geography is a factor there too, and highly urban or rural regions are often associated with reduced access to care, likely due to complex reasons, according to Patzer, who was not involved in the new study.

The current report didn’t examine the socioeconomic status of the patients, nor interview them to determine their attitudes toward end-of-life care before they died.

“There may be cultural differences, family preferences, patient preferences in end-of-life care, which is a very personal issue, that could explain some of these racial differences,” Patzer said.