Impact of Social Determinants of Health Interventions on Diabetes-Related Health Outcomes and Health Service Use

Social determinants of health (SDOH) such as food insecurity, lack of insurance, transportation deficits, and financial instability are associated with poor health outcomes, increased healthcare use and costs and diminished quality of life for individuals with chronic diseases such as diabetes. Addressing SDOH in clinical settings is essential for comprehensive care, yet research on the effectiveness of SDOH interventions in healthcare use, costs, and quality of life is limited. This dissertation evaluates two SDOH interventions for patients with diabetes in South Carolina’s largest health system. The first study assessed the costs and cost-effectiveness of a multidisciplinary teams-based program for underinsured and uninsured pregnant women with diabetes (pre-existing Type 1 or Type 2 or gestational diabetes) and SDOH needs. A microcosting approach was used to assess program costs, including costs for fixed resources (e.g., diabetes technology), team member time, SDOH supplies, diabetes treatment, and outpatient costs. A Markov cohort model was used to estimate the incremental program costs in reducing diabetes-related hospitalizations in pregnancy compared to standard care. Compared to standard care (mean [SD] = $1,114.96 [1,033.60]), the MOMs program cost $19,951 per pregnancy (range = $2,747.72 - $76,526.90). The standard care group dominated in cost-effectiveness for all diabetes type except gestational diabetes ($351.94 per hospitalization avoided, accounting for program, outpatient, and hospitalization costs). The second study evaluated a resource navigator program for patients with food insecurity and diabetes and/or hypertension, using a matched cohort design. Difference-in-difference specifications were used to examine six-month differences in clinical outcomes (HbA1c, BMI, blood pressure) and healthcare costs (total, primary, inpatient, and emergency department) between patients receiving resource navigation and a matched cohort that did not. Quality of life changes were also assessed for patients with navigator support. Patients with navigator support had $187.40 greater increase in primary care costs over six months and improved quality of life. Total healthcare, inpatient, and emergency department costs, and clinical outcomes did not differ between groups. These findings suggest that SDOH programs may enhance patient engagement and quality of life in diabetes care but incur significant costs, raising important budgetary implications for health systems and policy discussions. Future research should prioritize evaluating underexplored costs and outcomes associated with SDOH programs and examine program features to understand their impact on patient health.