Health Insurance and Interhospital Transfer for Critically Ill Patients With Respiratory Failure.

Importance: Critically ill patients with acute respiratory failure may benefit from transfer to higher-volume centers with specialized care. However, health insurance is often considered prior to interhospital transfer and may represent a factor other than severity of illness that influences transfer processes and outcomes for patients with respiratory failure. Objective: To examine the association between patient health insurance, interhospital transfer, and mortality for critically ill patients with acute respiratory failure. Design, Setting, and Participants: This retrospective cohort study using data from the Premier Healthcare Database included critically ill patients aged 18 years or older with acute respiratory failure receiving mechanical ventilation and intensive care within the first 3 days of hospitalization from January 1, 2017, until September 30, 2021, at academic and community hospitals across the US. Data were analyzed from October 2023 through August 2024. Exposure: Patient health insurance, categorized as commercial, Medicaid, Medicare, uninsured, or other. Main Outcomes and Measures: Multivariable logistic regression was used to estimate the associations between patient insurance type, receipt of interhospital transfer, and mortality, accounting for age, sex, severity of illness, comorbidities, and year. A shared frailty model was used to examine timing of interhospital transfer by insurance status. Results: There were 703 392 hospital admissions of critically ill patients with acute respiratory failure receiving invasive mechanical ventilation at 824 hospitals. The mean (SD) age patient age was 60.5 (17.0) years, and 400 126 (56.89%) were male; 30 613 (4.35%) underwent interhospital transfer, and 263 261 (37.43%) died or were discharged to hospice. In adjusted analyses, there were lower odds of undergoing interhospital transfer for patients without insurance compared with commercial insurance (adjusted odds ratio [AOR], 0.56; 95% CI, 0.51-0.61; absolute difference in estimated probability of transfer, 2.39 percentage points; P < .001). Patients without insurance experienced significantly higher odds of mortality (AOR, 1.31; 95% CI, 1.25-1.37; P < .001), and having no insurance was associated with slower time to interhospital transfer (adjusted hazard ratio, 0.72; 95% CI, 0.68-0.76; P < .001) compared with having commercial insurance. Conclusions and Relevance: In this cohort study, a lack of health insurance was associated with lower odds of interhospital transfer and higher odds of mortality among critically ill patients. The findings suggest a need to better understand drivers of the interhospital transfer process and ensure that decisions for transfer are made equitably to improve outcomes for critically ill patients.