A cohort study of hospitalized patients found that race and rurality have an impact on healthcare-associated infection (HAI) risk and outcomes, researchers reported yesterday in JAMA Network Open.
The study, conducted at three US urban and suburban hospitals, found that Black urban patients have a lower risk of HAIs than do White urban patients. But Black rural patients with HAIs have a significantly higher risk of intensive care unit (ICU) admission and in-hospital death than White urban patients, even after accounting for potential confounders.
The authors of the study say the findings likely reflect the "greater burden of structural and systemic barriers to health faced by Black individuals" and highlight the importance of considering how the intersection of race and rurality affects health outcomes.
"Although race and rurality are not biological constructs, they are important proxies for structural disadvantage, reflecting undermeasured or unmeasured social risk," they wrote. "As such, they could serve as important markers for individuals who should receive additional clinical attention to reduce adverse events."
Higher risk of ICU admission, death in Black rural patients
For the study, a team of researchers from Washington University School of Medicine in St. Louis examined data on patients hospitalized for 48 hours or more at one urban and two suburban hospitals from January 1, 2017, through August 31, 2020. They classified patients on the basis of the combination of two social determinants of health (SDOH): Patient race (Black or White) and rurality of the patient's home (based on Zip code).
As defined by the authors, SDOH are nonbiological factors affecting health that are outside of a person's control. They chose race and rurality to serve as proxies for structural racism and disinvestment in rural communities, two factors that have contributed to differential healthcare access and quality and have led to pervasive inequities in health outcomes.
Black populations, for example, experience higher rates of cardiovascular disease, stroke, and certain cancers than Whites, while people in rural areas are more likely to die from heart disease, stroke, and chronic lower respiratory disease than their urban counterparts.
Specifically, the researchers wanted to see how these two factors interconnect and affect risks and outcomes for HAIs—a topic on which little data have been published.
"Structural racism and rurality could influence HAIs through a number of mechanisms, including increased susceptibility to infection due to worse underlying health status at admission, interpersonal bias, or differential diagnosis and treatment in health care settings," they wrote.
Of the 214,955 patients (median age, 63 years; 50.6% female) included in the study, 71,391 (33.2%) were Black urban, 108,273 (50.4%) were White urban, 1,099 (0.5%) were Black rural, and 34,192 (15.9%) were White rural. White urban patients were the reference group.
Although race and rurality are not biological constructs, they are important proxies for structural disadvantage, reflecting undermeasured or unmeasured social risk....As such, they could serve as important markers for individuals who should receive additional clinical attention to reduce adverse events.
Recognized HAIs occurred during 6,699 admissions (3.1%) and included 1,572 bloodstream infections, 2,479 respiratory infections, and 3,146 urinary tract infections. Compared with White urban patients, Black urban patients had a decreased risk of HAI (adjusted relative risk [aRR], 0.81; 95% confidence interval [CI], 0.75 to 0.87), White rural patients had an increased risk (aRR, 1.12; 95% CI, 1.05 to 1.20), and Black rural patients had a similar risk (aRR, 1.08; 95% CI, 0.81 to 1.44) after accounting for potential confounders (including age, sex, comorbidities, body mass index, and measures of poverty). The results were consistent across all types of HAI.
But among the 653 HAI patients who were admitted to the ICU, Black rural patients had a nearly twofold increased risk of ICU admission (aRR, 1.92; 95% CI, 1.16 to 3.17) compared with White urban patients, while White rural patients (aRR; 1.12; 95% CI, 0.94 to 1.34) and Black urban patients (aRR; 0.96; 95% CI, 0.79 to 1.17) had comparable risks to White urban patients.
Similarly, among the 1,170 HAI patients who died, Black rural patients had a much higher risk of in-hospital death (aRR, 1.78; 95% CI, 1.26 to 2.50) than White urban patients, while White rural patients (aRR, 1.02; 95% CI, 0.89 to 1.18) and Black urban patients (aRR, 0.99; 95% CI, 0.86 to 1.15) had similar risks.
Sensitivity and subgroup analyses agreed with the main findings for both ICU admission and death.
"Collectively, these findings suggest that SDOH may contribute to patient outcomes through structural mechanisms linked to racism, rural disinvestment, and care delivery," the authors wrote.
Understanding what's beneath the inequities
The authors suggest the markedly increased risk of ICU admission and death in Black rural patients could be attributed to a factor that has been documented in previous studies—that Black patients are more likely than White patients to receive non–first-line antibiotics for infections. But they also suggest that Black rural patients may be sicker in ways they could not measure.
"On a national level, the worst health outcomes for cardiovascular disease, cancer, diabetes, and many other conditions are seen at the confluence of race, rurality, and poverty; these markers may translate into a poorer ability to tolerate or compensate for an HAI," they wrote.
But in an accompanying commentary, J. Danielle Sharpe, PhD, of the Centers for Disease Control and Prevention, says there are more factors involved.
"White urban patients and Black rural patients are affected by unique sets of social, structural, and systemic barriers and opportunities before and during admission to a facility that influence different pathways to developing an HAI, such as patient-practitioner relationships, quality of accessible health care facilities, neighborhood socioeconomic opportunity, transportation systems, and health system investment," Sharpe wrote.
The study authors conclude that additional studies are needed to "further investigate the relationships underpinning these inequities and develop comprehensive solutions to achieve health equity." Sharpe, who points out that the study also found inequities among White rural patients, says the findings "suggest a need to understand the intersectional experiences of patients to develop interventions to address factors placing them at risk of HAI and severe outcomes."
Sharpe adds that a greater focus on intersectionality in HAI surveillance could also yield solutions.
"Enhancing HAI surveillance priorities by placing a greater focus on examining intersectionality might advance progress toward achieving health equity," she wrote.