NEW ORLEANS –
According to the research, released at the annual meeting of the American Society of Hematology, the biggest disparities affected Asian/Pacific Islander patients with PE. While they were the least likely among ethnic groups to be hospitalized for PE, the odds were 53% higher that they’d die in the hospital (adjusted odds ratio, 1.53; 95% confidence interval, 1.32-1.78), and 24% lower that they would get advanced therapies (aOR, 0.76; 95% CI, 0.59-0.98, P values not provided in this study).
“The findings really raise the importance of this research area and call for vigorous future research to try to better identify why we see these patterns and then come up with solutions to solve them,” said hematologist and study coauthor Mary Cushman, MD, of the University of Vermont, Burlington, at an ASH news briefing.
Dr. Mary Cushman
As Dr. Cushman noted, details about disparities in PE care are limited. It’s known that “Black people have a twofold greater mortality from pulmonary embolism compared to other groups, and this is a persistently observed disparity over many years,” she said. However, “little is known about the relationships of social determinants with treatment and course of pulmonary embolism,” she added.
The researchers used data from the Nationwide Inpatient Sample to track 1.1 million U.S. hospitalized patients with PE from 2016 to 2018. PE was the primary diagnosis in 615,570 patients (54.8%), and 66,570 (5.9%) had high-risk PE.
Among ethnic groups, hospitalization rates “differed pretty dramatically,” Dr. Cushman said. The researchers found that Blacks had the highest rate of PE hospitalization (20.1 per 10,000 person-years; 95% CI, 20.0-20.2), followed by Whites (13.1 per 10,000 person-years; 95% CI, 13.1-13.2), Hispanics (6.0 per 10,000 person-years; 95% CI, 5.9-6.1), Native Americans (5.6 per 10,000 person-years, 95% CI, 5.4-5.7) and Asians/Pacific Islanders (3.0 per 10,000 person-years; 95% CI, 2.9-3.1). Overall, the rate was 14.9/10,000 person-years.
With regard to treatment, therapies defined by the researchers as advanced – systemic thrombolysis, catheter-directed therapy, surgical embolectomy, and venoarterial extracorporeal membrane oxygenation – were also less commonly used in treating ethnic minorities.
These treatments were used in 5.5% of all patients, and 19% of those with high-risk PE. After adjusting for nearly 20 factors such as age, sex, and place of residence, researchers found that the odds that a patient would receive advanced treatment were lower in Blacks (aOR, 0.87; 95% CI, 0.81-0.92) and Asians/Pacific Islanders (aOR, 0.76; 95% CI, 0.59-0.98) compared with Whites. The differences in Hispanics and Native Americans were not statistically significant.
As for insurance, those with Medicare and Medicaid were less likely to get advanced treatment vs. those with private insurance (aOR, 0.73; 95% CI, 0.69-0.77 and aOR, 0.68; 95% CI, 0.63-0.74, respectively). Differences among income levels were not statistically significant.
In the hospital, 6.4% of patients with PE died, as did 50% of those with high-risk PE. There was no statistically significant difference in death rates overall between Whites and Blacks or Native Americans. However, Asians/Pacific Islanders had a much higher death rate (aOR, 1.53; 95% CI, 1.32-1.78), as did Hispanics (aOR, 1.10; 95% CI, 1.00-1.22).
Why are Asians/Pacific Islanders at such high risk of death? Dr. Cushman noted that, while their hospitalization rate is low, they are especially likely to present with high-risk PE.
The difference in death rates between patients with Medicare/Medicaid insurance and those with private insurance was not statistically significant. Neither was the difference in death rates among income groups vs. the highest quartile with one exception: The lowest quartile (aOR, 1.09; 95% CI, 1.02-1.17).
As for the reasons for the higher risks among various groups, Dr. Cushman said there are several possible theories. “It could be due to differences in awareness of PE symptoms: They don’t know how ill they are, so they present later in the course. Or they might have less trust in the system, which might lead to delayed care. Or it could be that they have misdiagnosis of PE symptoms when they present initially.”
Alternatively, she noted, the differences “could be rooted in structural racism and other social determinants of health that weren’t measured, such as education level and quality of education.”
In an interview, Dr. Cushman expressed the hope that “clinicians will think about these findings in terms of how they take care of patients and try their best to recognize any unconscious biases that might creep into their approach. In addition, as a society we need more education of the general public about PE. Some of our findings might be caused by delayed care due to lack of recognition of a need to seek care.”
In an interview, University of Pittsburgh vascular surgeon Rabih Chaer, MD, MSc, who didn’t take part in the study, said it relies on a "large dataset which offers valuable information but with limited granularity and follow-up. This limits the accurate categorization of PE severity, as well as comorbidities, all of which impact outcomes and survival.”
For example, Dr. Chaer said, PE treatments can be limited in some patients due to their comorbidities that cause bleeding risk. Still, Dr. Chaer said the findings mesh with his own research that has shown racial disparities in PE treatment and outcomes, including a 2021 study. "While we did not see a difference by race in in-hospital mortality, Black patients hospitalized with PE are younger with a higher severity of disease compared with White patients,” he said. "Although Black patients are less likely to receive an intervention overall, this differed depending on PE severity with higher risk of intervention only for life-threatening PE." And a 2022 study found that “patients with PE from deprived neighborhoods have worse survival beyond the index [first] admission and were more likely to suffer from cardiovascular or PE-related causes of death in the first year after the index pulmonary embolism,” he said.
Dr. Chaer noted that his research team “is actively working on the next steps beyond identifying the fact that there are racial disparities in PE treatment and outcomes. We are fortunate to have access to a large granular database with long-term follow up and are currently reviewing the medical record details to identify causes for disparities and potential solutions.”
Dr. Cushman received funding from the National Institutes of Health. Other study authors report various disclosures. Dr. Chaer has no disclosures.