Substance use screening, brief intervention, and referral to treatment among working-age medicaid patients in Wisconsin: Impacts on healthcare utilization

The goals of this dissertation are to: 1) describe healthcare utilization by levels of substance use risk severity; 2) evaluate the change in healthcare utilization associated with substance use screening, brief intervention, and referral to treatment (SBIRT); and 3) determine the healthcare impacts of SBIRT among individuals with diabetes.;Data for this dissertation came from the Wisconsin Initiative to Promote Healthy Living (WIPHL) screening and brief intervention project and Wisconsin Medicaid claims data. The study sample included 7,367 treatment and 6,751 comparison group working-age Wisconsin Medicaid participants. Methods included bivariate analysis and difference-in-differences regression models to evaluate the effect of SBIRT on relative changes in outpatient, inpatient, and ER utilization over a 24-month follow-up period. Study participants were stratified by Medicaid-Medicare dual eligibility status for all analyses.;Results show statistically non-significant differences in baseline healthcare utilization among individuals with greater substance use risk severity compared to individuals with low-risk. Individuals with harmful and likely dependent risk severity have higher rates of disability, alcohol-related and mental health conditions, other drug use, and hypertension. Individuals with likely dependent risk severity also have higher rates of diabetes. Over the 24-month follow-up period, SBIRT was not associated with statistically significant changes in inpatient days or ER utilization compared to those not receiving SBIRT. SBIRT did, however, show changes in total utilization patterns that indicate an increase in awareness of healthcare needs and a change in utilization away from high-cost inpatient and ER services toward outpatient services. Among dually eligible diabetic patients, receiving SBIRT services resulted in a significantly larger decrease in inpatient days per year (-2.2; p<0.05) and inpatient admissions per year (-0.25; p<0.01).;This dissertation shows that SBIRT services universally implemented and administered by paraprofessionals may lead to more efficient use of healthcare services over a 24-month time period. SBIRT implemented as a routine service could result in state Medicaid system cost savings of...