Patients who receive care in a for-profit hospital are more likely to be readmitted than those who receive care in nonprofit or public hospitals, according to a new study published by University of Illinois at Chicago researchers.

The study, which is published in PLOS ONE, analyzed readmission data obtained from the national Hospital Readmission Reduction Program (HRRP) from 2012 to 2015 for six major and common diseases: heart attack, heart failure, coronary artery bypass surgery, pneumonia, chronic obstructive pulmonary disease, and total hip or knee replacement surgery. Using provider identifiers verified with a Center for Medicaid and Medicare Services’ report, the researchers compared readmission rates and categorized the hospitals by type: public, for-profit or nonprofit.

They found that across all six major diseases there was a statistically significant difference in readmission rates based on type. Hospitals with fewer readmissions than expected, based on a government ratio accounting for disease severity, were primarily public and nonprofit. In contrast, hospitals with more readmissions than expected were predominated by for-profit hospitals.

In each category, for-profit hospitals had the highest mean and median readmission ratios.

“It is remarkable to see such clear data in a study like this,” said Andrew Boyd, the corresponding author and associate professor of biomedical and health information sciences at the UIC College of Applied Health Sciences. “There is not a single category in which for-profit hospitals shined when it came to readmissions. This was unexpected. It was also surprising to see that the trend existed independent of geography.”

The researchers say that while the study shows there is a correlation between hospital type and readmission rates, the data does not provide any clues as to why for-profit hospitals fare worse than nonprofit or public hospitals. Possible reasons mentioned in the paper include a relative lack of resources at for-profit hospitals due to higher taxes and a focus on maximizing profit that may steer funds away from investment in staff or medical technology.

“This study shows an important national trend to which policymakers, health care providers, researchers and patients should pay attention, especially in light of a changing health care landscape marked by discussions on reimbursement rates and network consolidations, which are occurring across all types of hospitals,” Boyd said.

More important, Boyd says, is what this means for patients.

“Readmission to the hospital means additional days and weeks away from work, hobbies, friends and family. At the very least, I hope this study helps bring awareness to the fact that data on readmission rates at all types of hospitals is available to the public,” he said.

“As we transform health care, we need to pay attention to the data to make sure we make it better – for example, by reducing readmission rates – not worse,” Boyd said. “Because we used publicly available data, the door is wide open for future studies to explore these trends in more detail.”

Co-authors on the paper are UIC’s Manish Mittal, Chih-Hsiung Edward Wang and Abigail Goben.