Mobile Medical Units Expand Access but Raise Costs for Homeless Veterans in VA Program Study

Key Takeaways:

• Mobile medical units (MMUs) might improve outreach and care for high-risk homeless veterans, but they do not appear to provide better patient outcomes. Patients using MMU care had slightly more outpatient visits and fewer inpatient stays for substance use disorder (SUD) care and domiciliary care, though the reasons for this change in utilization are unknown.
• Patients using MMUs had higher care costs. Total costs for patients in this cohort increased by over $1700, contradicting the belief that MMUs could reduce health care costs.
• This study assessed a small population for a short period of time, leading to many unverified associations. Future research is needed to examine the long-term impact of MMUs on treating homeless veterans.

In order to provide more accessible care to homeless veterans, the US Veterans Affairs’ (VA) Homeless Patient Aligned Care Teams (HPACT) program deployed MMUs to 24 VA medical centers in late 2023. This study assessed the impact of MMUs on VA outpatient and inpatient visits as well as total care costs.

MMUs and Health Care Utilization and Costs for Homeless Veterans

The data from the 2700 veterans using MMU care was compared with 131 991 veterans who received usual primary care. Patients in the MMU group were more at risk than veterans receiving usual care because they had more recorded comorbidities and higher rates of substance use.

Patients using MMU care had more outpatient and emergency department (ED) visits than patients receiving usual care, although these increases were small. Patients with MMU care also had fewer inpatient stays for SUD care and domiciliary care. These findings, however, do not establish a causal relationship between MMUs and care utilization; they are simply associations.

Patients in the MMU group increased health care costs by more than $1700. This cohort had higher outpatient costs and lower inpatient costs than patients receiving usual care. Overall, patients using MMUs had higher total costs than patients with usual care, indicating that MMUs may not be as cost-effective as previously expected.

Study Limitations and Future Research

This study examined MMUs during the early stages of implementation and observed a small population of veterans. These factors may explain the limited findings and highlight the need to record the long-term effects of MMUs across a larger cohort.

Although little research has been done to monitor the effects of MMUs on care for homeless veterans, the study’s authors believe their implementation will improve outreach and access. They said, “MMUs may not reduce all types of acute care, but they may be an effective modality to reach veterans experiencing homelessness with access barriers and greater complexity and needs for care.”

Reference

Yoon J, Chow A, Weber JJ, Wong EP, Blonigen DM, Tsai J. Utilization and costs of mobile medical units for veterans experiencing homelessness. Jama Netw Open. 2026;9(1):e2555068. doi:10.1001/jamanetworkopen.2025.55068