Study Identifies Racial Differences in Patient Safety in Hospitals

July 26, 2021 — Black patients have a higher rate of adverse safety events than white patients when they are admitted to the same hospital, regardless of insurance coverage type or the percentage of hospitalized patients who are Black, according to a new Urban Institute study.

The study, which was funded by the Robert Wood Johnson Foundation, is one of several analyses that have shown there are racial differences in patient safety in hospitals. But it is the first paper to show that this finding holds true within the same hospital, according to study author Anuj Gangopadhyaya, a senior research associate at the Urban Institute.

Gangopadhyaya looked at 2017 hospital discharge data from 26 states. The database included 2,347 hospitals, but facilities with too few at-risk discharges of Black or white patients for patient safety indicators were excluded. Eighty percent of Black admissions and 44% of white hospitalizations were in just 348 hospitals.

For the study, the author used software developed by the U.S. Agency for Healthcare Research and Quality (AHRQ) to identify avoidable inpatient adverse safety events, focusing on 11 patient safety indicators. Four of them were general safety measures, such as pressure ulcer rates and central venous catheter-related bloodstream infection rates. The other seven measures were those related to surgical procedures, such as post-surgery sepsis infection rates.

For six of the 11 safety indicators, including four of the seven surgery-related measures, Black adults had a significantly higher rate of adverse patient safety events than did white adults in the same age group, of the same gender, and treated in the same hospital. White patients had worse care on two indicators. The quality of care was similar for Black and white patients on the other three measures.

The differences in patient safety events between white and Black patients within the same hospital were particularly high on the surgery-related indicators. The racial difference was 20% for the perioperative hemorrhage or hematoma rate, 18% for the postoperative respiratory failure rate, 30% for the perioperative pulmonary embolism or deep vein thrombosis rate, and 27% for the postoperative sepsis rate.

Within the same hospital, Black patients also had higher rates of adverse safety events than white patients did on pressure ulcers and central line infections.

Insurance Effect

Nonelderly Black patients may be more likely to have Medicaid coverage or be uninsured and are less likely than white patients to have private insurance, according to the study. Past research shows that differences in insurance types may be related to racial differences in financial incentives for hospital care services and that these could drive within-hospital differences in care quality.

The Urban Institute study found that adjustments for patient coverage types within hospitals “attenuates,” or weakens, the results but don’t change the overall trend. For example, Black patients were estimated to be 27% more likely to have postoperative respiratory failure relative to white patients treated in the same hospital. Adjusting for insurance coverage type reduced this difference to 14%, which is still a significant gap.

The study also looked at within-hospital differences in safety indicators among Medicare patients, who represented the largest insurance type among the hospitalized patients. The differences in patient safety between Black and white patients were slightly larger among Medicare enrollees than among all people in the same hospital.

“Differences in insurance coverage between Black and white patients are not a major contributing factor driving differences in adverse patient safety events between Black and white patients within the same hospital,” the study concluded.

Finally, the study examined racial differences in patient safety in hospitals that cared for larger shares of Black patients and in hospitals that had larger financial resources.

Hospitals where more than 25% of hospitalized patients were Black were compared with the other hospitals in the sample. Despite some differences on individual safety indicators, “the share of Black patients served by a hospital is largely unrelated to the differences in quality delivered to Black and white patients within a hospital,” the study says.

Similarly, the amount of resources a hospital has — as measured by its percentage of privately insured patients — seemed to have no bearing on the differences between the patient safety indicators for Black and white patients, according to the study.

Reasons for Safety Differences

Systemic racism plays a role in the differences between Black and white patients on safety indicators, Shannon Welch, senior director of the Institute for Healthcare Improvement (IHI), tells WebMD. But when members of different races receive unequal treatment from the same team of doctors and nurses in the same hospital, she says, hospitals have to dig deeper into their data so they can figure out how to provide the same quality of care to everyone.

One health system, she notes, found that the time to treatment with tPA for suspected strokes was longer for Black patients than for white patients. This was a very important finding, as tPA can protect stroke patients against further brain damage. The system analyzed its process data and improved the process for everyone, so the difference between how patients of different races were treated disappeared.

But that still leaves the question of why these disparities exist. One possible reason is that most doctors are white, so Black patients are frequently not treated by a doctor of their own race.

“We know the doctor-patient relationship is very important,” Welch says. “It needs to be rooted in trust and understanding, and there needs to be clear communication. And there is something to be said for what happens when a patient comes in and sees a doctor who looks like them, who has the same cultural experience and background. It helps create a safe space.”

Some doctors may also be biased against people of a different race, whether they realize it or not, she says.

“The reality is that we all have biases, because we swim in the water of our environment. The things we’ve been taught, that we’ve heard, that we’ve learned through the observations of others shape the lens through which we see the world. And we know there have been false narratives in medical education: for instance, that the nerve endings in Black people are different, so that Black people have a greater tolerance for pain.”

These false narratives, which stem from an earlier era, assume that there are biological differences among the races — a theory that persists today, even in some clinical guidelines.

“The false assumption that there are biological differences between races has been baked into the way that physicians practice,” Welch says.

Unequal Maternal Outcomes

Welch has done extensive research for IHI on inequity in maternal outcomes.

“If you look at the maternal mortality rate, for example, Black women are more likely to die in childbirth of pregnancy complications than white women, even after we control for the factors of educational status, income level, and type of insurance — all those things we expect would be protective factors. In this case, they’re not.

“What I’ve learned from my work on improving maternal health outcomes is a need for a level of respectful care. Also, when Black patients come in, physicians should listen to the questions they have and the concerns they raise and believe Black patients when they say they’re experiencing pain or having a particular issue.”

Since 2017, IHI has been conducting a patient safety equity initiative that now includes 22 health systems, she says, noting that she’s glad the Urban Institute study has cast a spotlight on these issues.

“What this study shows is that we can’t have quality and safety in patient care without equity,” Welch says.