News Release

A community health worker intervention reduces hospital readmissions

The benefit was seen among patients discharged to short-term rehabilitation

Peer-Reviewed Publication

Massachusetts General Hospital

BOSTON – The Community CAre Transitions (C-CAT) clinical trial, which paired community health workers (CHWs) with patients admitted to Massachusetts General Hospital (MGH), has found that fewer intervention group participants were readmitted within 30 days than control group participants. The effect was significant for those discharged to short-term rehabilitation but not for those discharged home. The study has been published in JAMA Network Open.

“These results indicate that CHW interventions may help reduce hospital readmissions and improve preventive care among some clinically complex patients within an accountable care organization,” says lead author and C-CAT trial principal investigator Jocelyn Carter, MD, MPH, a physician-scientist in the MGH Division of General Internal Medicine.

Hospital readmissions have been identified as a major contributor to health care costs, accounting for a third of total U.S. health care expenditures. Thirty-day readmissions are common and about 27% of adult 30-day readmissions are estimated to be preventable. Previous studies have identified factors such as medical complexity and social determinants of health as contributing to readmission risk.

While community health workers are one of few interventions demonstrating compelling evidence of improving outcomes in clinically and socially complex populations, most CHW studies have focused on disease-based cohorts. The study of CHW interventions at the time of hospital discharge has been underutilized and prior trial results have been mixed.

In the C-CAT study, CHWs, trained in basic knowledge of clinical conditions, provided health coaching and connected patients to specific low and no-cost resources (e.g., food, transportation, housing-related) contributing to gaps in care. Using the framework of motivational interviewing and psychosocial support, CHWs sought to strengthen patient connections to primary care while addressing unmet needs. To test the effect of CHW care delivery on 30-day readmission in a population insured by a Mass General Brigham accountable care organization, 278 participants were randomized to receive usual care along with the 30-day CHW intervention and 273 participants were randomized to usual care only. Members of the C-CAT study team enrolled patients on six internal medicine units from 2017 to 2019. CHWs met participants in-hospital prior to discharge.

Of the 550 participants analyzed, the mean age was 70.1, 48.4% were women, and 70.5% were Medicare insured. All trial participants had a mean of three hospitalizations in the 12 months prior. Overall, 24.5% of control and 21.7% of intervention participants were discharged to rehabilitation with a mean length of stay of 3.9 days.

Just 12.6% of intervention group participants were readmitted in the 30 days following hospital discharge, as opposed to 24.5% of control participants. However, Carter and her colleagues noted a statistically significant reduction in readmissions among patients discharged to rehabilitation but not in those discharged directly home: Intervention vs. control participants discharged to rehabilitation demonstrated a 32.3% reduction in readmissions (5.0% vs 37.3%) compared to a 5.7% reduction seen in those discharged home (14.7% vs 20.4%) . In addition, fewer intervention than control patients had missed appointments (22.0% vs. 33.7%) and ED visits (11.2% vs. 16.8%).

While the intervention effect was seen in patient discharged to short-stay rehabilitation prior to returning home, the researchers note that prior studies have shown that patients with complex co-morbidities discharged to rehabilitation facilities have markedly elevated rates of readmission, ranging from 28% to 75%. CHWs might have positively influenced these numbers by addressing unmet medical and social issues that occurred during the transition from rehabilitation to home, and improving communication between patients, rehabilitation staff, and the primary care providers after discharge. Carter notes: “Surprisingly, there was a strong and significant reduction in 30-day readmissions for patients discharged to rehabilitation. This is a population with limited demonstrated interventions shown to improve outcomes. Additional research is needed to examine why this effect was seen as well as which patients benefitted most from certain CHW intervention activities.”


Carter is an instructor in Medicine at Harvard Medical School (HMS). Senior author Anne Thorndike, MD, MPH, is an investigator in the Division of General Internal Medicine at MGH and associate professor of Medicine at HMS. Additional co-authors are CHW staff members Susan Hassan, B.A., Anne Walton, RN, AsEd AE-C; Karen Donelan, ScD, EdM, of the MGH Department of Medicine and the Mongan Institute and who is also the Stuart H. Altman Chair at the Heller School at Brandeis University; and Liyang Yu, MS Bioinformatics Specialist at MGH.


The study was supported by a Partners HealthCare Center for Population Health Delivery System Innovation Implementation Grant and the Healthcare Transformation Lab at MGH.

About the Massachusetts General Hospital

Massachusetts General Hospital, founded in 1811, is the original and largest teaching hospital of Harvard Medical School. The Mass General Research Institute conducts the largest hospital-based research program in the nation, with annual research operations of more than $1 billion and comprises more than 9,500 researchers working across more than 30 institutes, centers and departments. In August 2020, Mass General was named #6 in the U.S. News & World Report list of "America’s Best Hospitals."

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.