Patterns of Outpatient Mental Health Care Utilization Among Medicaid Patients Served by Harborview Mental Health and Addictions Services (HMHAS) After Population Health Stratification (PHS) Model Implementation

Abstract

University of Washington Department of Health Systems and Population Health Medicaid patients with the greatest need for mental health services often do not receive adequate outpatient mental health services, resulting in worse outcomes for the patient and increased utilization of costly and less effective inpatient and emergency services. Those with severe mental health needs disproportionately experience co-occurring health challenges and social adversities. Increasingly, population health stratification (PHS) and value-based payment strategies are being implemented to incentivize mental health care providers within Medicaid integrated care networks to increase outpatient mental health services for clients at greatest risk of adverse health and social outcomes. In King County, Washington, a new PHS model and value-based payment reform was implemented by the King County Integrated Care Network (KCICN) in July 2020 with the goal to increase quality of care for populations with the greatest need. To support Harborview Mental Health and Addictions Services (HMHAS) – a Seattle outpatient mental health clinic – we conducted a descriptive analysis examining their patient population and whether PHS level of care was related to engagement in outpatient services and type of outpatient services in the context of the PHS level of care and value-based payment model. This descriptive analysis examined Recovery Services Medicaid patients ages19 and older who were served between July 2020 – December 2022. We also conducted additional analyses to improve understanding of demographic and health-related characteristics among patients and the relationship between the PHS and the Level of Care Utilization System (LOCUS) levels of care, which each serve as indicators of patient need for mental health services. We found that around 1 in 3 patients required a higher level of care than can be provided in an outpatient setting, that patients with the higher levels of care were disproportionately unable to meet service delivery adherence, and that patients with higher levels of care had higher prevalence of case management and peer services than lower level of care patients. Findings suggested that the clinic may not be equipped to meet the high needs of patients and that efforts to meet the basic needs of these individuals may be important to support their engagement in mental health services. Future research is needed to examine unintended consequences of PHS and value-based payment models and that explores strategies that successfully engage high need patients in outpatient care, such as a strong therapeutic alliance and more intensive case management and housing supports.