The Influence of Hospital Urbanicity on Mortality in Patients With Acute Respiratory Failure: A National Cohort Retrospective Analysis

Discussion

Our primary aim was to highlight differences with respect to inpatient mortality and hospital stay among urban and rural hospitals in patients with respiratory failure necessitating mechanical ventilation. Our main finding was that the odds of mortality and prolonged hospital stay in patients with respiratory failure were higher in both urban nonteaching and teaching compared to rural hospitals. Notably, far fewer patients with respiratory failure were treated at rural versus urban teaching or urban nonteaching hospitals. This study agrees with current literature, which suggests drastic differences in patient populations; as such, practical risk stratification protocols should be employed that may allow for appropriate allocation of resources.

Factors underlying urban versus rural hospital differences are not completely identified or understood. Several studies have shown poorer health outcomes among rural compared to urban hospitals for cardiovascular and renal disease, whereas other studies have shown higher morbidity and mortality in urban locations.^17-22 Similarly, we showed higher mortality among urban versus rural hospitals following acute respiratory failure. One important explanation is the differences in the underlying etiology responsible for respiratory failure requiring ventilation.

Although urban nonteaching and teaching hospitals are generally thought to be equipped with subspeciality care and advanced technology, these hospitals may be located in communities that harbor mistrust in the medical community due to centuries of mistreatment.^23,24 This alone may lead to delays in clinical presentation and worse outcomes. Other possibilities include environmental pollution and poor air quality in urban areas that may predispose patients who live in urban areas to more severe disease. Another possibility as to why mortality may be higher at urban versus rural hospitals is that perhaps critically ill patients with respiratory failure are being transferred out of rural hospitals, which may lack the financial security or physical resources to manage respiratory failure and associated comorbidities. More now than ever, we have seen this especially during the COVID-19 pandemic where smaller regional hospitals become easily overwhelmed and transfer patients to relief health care facilities that have extra resources and are more equipped to care for a larger number of medically complex patients.

The Centers for Disease Control and Prevention defines racism as a system consisting of structures and policies that assigns value and determines opportunity based on the way people look.²⁵ The Federal Housing Administration, established in 1934, perpetuated racial segregation primarily through “redlining,” refusing to insure mortgages in Black communities and dissuading housing developers from selling homes to Black buyers.²⁶ In the 1950s, “blockbusters” purchased homes at lower prices in predominately White communities and resold to Black buyers for substantially higher prices.²⁶ Throughout the 20th century, other practices such as exclusionary zoning laws, racial steering, urban renewal following the 1949 Housing Act, and interstate construction through predominately black communities all contributed to urbanicity.^27,28 These practices, initially intended to encourage racial segregation, are now associated with a higher density of tobacco and alcohol retailers and fewer health-promoting resources.^29,30 It is these practices and policies that have shaped urban communities and the health consequences of living in these communities, and recent data from the Pew Research Center suggest urban communities continue to have the highest percentage of minorities.³¹ We believe it is not the urbanicity that leads to inequality but rather centuries of racial covenants and structural inequalities that encouraged segregation and consequently poorer health outcomes among ethnic minorities.^32,33

We also observed stark differences in hospital urbanicity represented in the Southeastern United States, where among urban teaching hospitals > 20% are below the Mason-Dixon line. Perhaps these data are confounded by the greater prevalence of southern states among urban hospitals, where southern states consistently rank among the worst in the United States for health and wellness according to America’s Health Rankings annual reports.³⁴ Additionally, in South Carolina, only 66% of the population lives in urban areas (whereas the national average is 84%), yet these southern states have among the highest percentage of urban hospitals. The discrepancy between people who live rurally but may need to present to an urban hospital during a health crisis may lead to a time delay and worsening of clinical condition upon presentation to the hospital. Parcha and colleagues⁹ evaluated trends and geographic differences in acute respiratory failure and showed that the adjusted acute respiratory failure mortality rate was highest for males, non-Hispanic Blacks, those living in nonmetropolitan areas, and in southern states. These differences pre-COVID shed light into the current geographic distribution of COVID-19. It is clear that these hospitals face unique challenges. Therefore, we must further define the need and gaps in clinical care and appropriately risk stratify and develop policies/interventions to improve health outcomes.

The literature suggests rural hospitals are underfunded and understaffed when compared to urban counterparts. In a recent comparison of nursing resources among large urban, small urban, and rural hospitals, rural hospitals had the lowest number of nurses with the largest amount of patient burden per nurse than large urban and small urban hospitals. Furthermore, the degree of baccalaureate credentialing among the nursing staff was lower overall for rural hospitals than for large urban or small urban hospitals.³⁵ However, urban areas are densely populated with minorities, who face a different set of health care challenges. This has profound implications for the difficulties that these hospitals face and calls into question the need for policy reform and resource reallocation in health care. New strategies and revisions to current public health and fiscal policies would be beneficial to bridge the rural-urban gap, specifically by targeting the resource deficit for rural hospitals and health prevention in urban communities.

There is a paucity of literature examining hospital stay in patients with respiratory failure, although one can surmise that a variety of factors may contribute to this observed difference. First, aforementioned differences in mortality rates may suggest that urban patients have worse clinical disease on presentation than rural patients, necessitating longer average periods of stay. Second, there may be differences in hospital discharge policies between urban and rural hospitals such that rural hospitals are generally able to discharge patients at earlier time points to rehabilitation and acute care facility following extubation compared to discharge policies at urban hospitals.

Whereas we do provide possible explanations for the observed differences among urbanicity cohorts, given the limitations of the study, the results should be interpreted with caution. Here we use NIS, an administrative database that uses billing codes to collect and store patient health information. As these codes were originally intended for billing, they do not capture the severity of disease, provider experience, specific or doses of medications, etiology of respiratory failure, ventilation management protocol, laboratory and microbiology data, and time spent on ventilator. With the use of NIS, we were unable to ascertain the number of patients who were transfers from outside hospitals, which could help to clarify the observed differences in hospital stay among urbanicity cohorts. Moreover, the database does not collect socioeconomic data beyond income and race. Given the retrospective nature of the data, we were only able to measure association and not causation. Such type of study may help drive hypothesis aimed to improve disparities between rural and urban hospitals.