Intensity of social needs case management services and changes in hospital and emergency department use among adult Medicaid beneficiaries

OBJECTIVES: We identify the association between high- and low-intensity case management services on hospital and emergency department (ED) use among CommunityConnect patients. 

BACKGROUND: Social needs case management services vary in intensity, including the modality, workforce specialization, and maximum caseload. CommunityConnect is a social needs case management program implemented by Contra Costa Health, a county safety-net health system in California's San Francisco Bay Area. 

METHODS: Due to the endogeneity of high-intensity services assigned to high-risk patients, we instrument for service intensity using the number of specialist case managers hired each month of enrollment. Zero-inflated negative binomial models with 2-stage residual inclusion estimated total and avoidable hospital admissions and ED visits 12 months post-enrollment for adult Medicaid beneficiaries enrolled between August 2017 and December 2018 (n = 19,782). 

RESULTS: Compared with low-intensity case management, high-intensity services were associated with a reduction in the incidence rates of inpatient admissions [incidence rate ratio (IRR) = 0.341, 95% CI: 0.106-1.102; P = 0.072], ED visits (IRR = 0.608, 95% CI: 0.188-1.965; P = 0.058), and avoidable ED visits (IRR = 0.579, 95% CI: 0.179-1.872; P = 0.091). No significant association was found between service intensity and the likelihood of an event being an excess zero. 

CONCLUSIONS: High-intensity social needs case management may be more effective than low-intensity service at reducing health care use for individuals with non-zero use, suggesting that intensive case management may be especially helpful in supporting discharge and transitions of care.