(Reuters Health) - In a large national study that included nearly 90 percent of all preterm and low-birth-weight babies born in the U.S. in a recent three-year period, researchers found that black infants were more likely than white infants to receive care in a lower-scoring neonatal intensive care unit (NICU).

The hospital’s quality of care is directly related to deaths and complications in newborns, said study coauthor Erika Edwards of the University of Vermont. Complications commonly seen in premature babies can have lifelong consequences. For example, she said, “Chronic lung disease is related to asthma which is already an issue in minority populations. And brain injury can cause developmental delays.”

To look more closely at the possibility that race and/or ethnicity play a role in where the most fragile infants got care and whether some sort of segregation was going on in NICUs across the nation, Edwards and her colleagues turned to the Vermont Oxford Network, an organization that collects data from hospital NICUs worldwide. Edwards is also director of data science for the network.

Network members contribute standardized data on all infants born after only 22 to 29 weeks of pregnancy or weighing 401 g to 1500 g (about 14 oz to about 3 lb.)

As reported in JAMA Pediatrics, the researchers focused on 134,871 infants born from January 2014 to December 2016. Some were born at hospitals with NICUs; others had to be transferred to these more sophisticated facilities.

NICU quality was determined based on nine factors, such as infant mortality during birth hospitalization, health-care associated bacterial or fungal infection, a timely eye exam, and chronic lung disease.

Overall there were 743 hospitals in the study, with 38 contributing one year of data, 28 contributing two years of data and 677 contributing data for three years. Among infants whose treatment was examined in the study, 36,359 were black, 53,895 were white, 21,808 were Hispanic and 5,920 were Asian.

When the researchers analyzed the quality of hospitals that the very low birthweight babies ended up, they found that minorities tended to end up at different hospitals than whites and that black babies were more likely to be treated at a lower-quality NICU than white babies.

Edwards doesn’t know yet why black infants are more likely to end up at a lower quality NICU and says that is a topic for future research. “Black people don’t always end up at the closest hospital to them,” she said. “And we don’t necessarily know why. Certainly there are a number of theories. It could be related to insurance and which hospitals accept which insurance. Where deliveries occur could depend on whether a physician has (is authorized) to deliver at a particular hospital.”

While there have been smaller studies showing similar results, this is the first to look at “the national picture,” said Dr. Elizabeth Howell, director of the Blavatnik Family Women’s Health Research Institute and a professor of obstetrics, gynecology and reproductive science at the Icahn School of Medicine at Mount Sinai in New York City. Howell coauthored an editorial accompanying the new study.

“We’ve been looking at these kinds of questions in medicine across the board, not just in neonatal care,” Howell said. “Residential segregation I think is one of the biggest factors. However, there are other factors. We need to understand the underlying causes if we are going to target interventions to reduce disparities and improve care.”

The new study is “important,” shedding light on NICU care for “the most vulnerable tiny infants, who can weigh as little as 14 oz.,” said Dr. Albert Wu, an internist and professor of health policy and management at the Johns Hopkins Bloomberg School of Public Health. “We now know that babies tend to be segregated by race and, more important, that black infants tended to be concentrated in hospitals with worse care. This kind of disparity can influence their health and quality of life for the rest of their lives.”

SOURCE: bit.ly/2Os2OVj JAMA Pediatrics, online March 25, 2019.