This study examines the impact on cost and health care utilization of providing substance abuse treatment for Medicaid managed care patients.  The study matched Medicaid and non-Medicaid patients and found that Medicaid patients incurred higher costs during the 12-month pre-intake period; however, during the three subsequent years, both groups medical costs declined an average of 30 percent largely through ER and other hospitalization reductions. 

Walter, L. J., et al. (2005). Medicaid chemical dependency patients in a commercial health plan: do high medical costs come down over time? Journal of Behavioral Health Services Research, 32(3): 253-63. DOI: 10.1007/BF02291826 http://www.ncbi.nlm.nih.gov/pubmed/16010182

Authors: Lawrence J. Walter, Lynn Ackerson, Steven Allen