Insurance status influences survival chances for critically ill patients

Does insurance play a role in which critically ill patients live or die?

The unfortunate answer may be yes, due in part to a difference in the rate of inter-hospital transfer, according to new research from the University of Michigan. 

The research team, led by Emily Harlan, M.D. and Thomas Valley, M.D. of the Division of Pulmonary and Critical Care Medicine, examined the factors that determined which critically ill patients with acute respiratory failure were transferred to high volume specialty hospitals for treatment.

Care in such hospitals is associated with a lower risk of death for patients on a ventilator.

We were motivated to do this study because there are times that, as doctors, we get a call from an outside hospital asking us to accept a patient for transfer to our ICU. We'll accept a patient, but then we're told that the patient's insurance needs to be reviewed first. We wanted to see if those experiences were unique to us."

Thomas Valley, M.D. of the Division of Pulmonary and Critical Care Medicine

"There are laws in place to ensure that anyone who needs emergency care is stabilized and admitted to the hospital. But those laws tend to end there. If a patient needs more advanced treatments at another hospital, there is nothing that requires hospitals to accept those patients for transfer-that's where factors like a patient's insurance might play a role."

Looking at data from more than 700,000 patients from throughout the U.S. who were critically ill and on ventilators between 2017 and 2021. Over half were insured through Medicare, 19 percent through Medicaid, 18 percent through commercial insurance and 6 percent were uninsured.

After controlling for patient characteristics, such as age, sex, chronic illnesses, severity of illness and the year they were admitted (to account for the COVID-19 pandemic), the team discovered that around 4 percent of patients underwent inter-hospital transfer and 37 percent of patients died or were discharged to hospice.

The odds of transfer for patients without insurance were nearly half that of patients with commercial insurance. Patients with Medicare or Medicaid were also less likely to receive inter-hospital transfer than those with commercial insurance. Patients without insurance or with Medicare or Medicaid were also transferred later during their hospital stays than patients with commercial insurance. 

Furthermore, patients without insurance had significantly higher odds of death relative to patients with commercial insurance.

This study adds to the growing body of evidence of a relationship between insurance status and inter-hospital transfer for serious health conditions.

"We need to further evaluate how hospitals make decisions to transfer patients to ensure transfer decisions are made equitably," said Harlan.