This study examines the notion that people with a co-occurring mental health and substance use disorders frequently use inpatient care. The study used utilization data from DE, OK and WA for clients who received at least one mental health or substance abuse service from the state mental health, substance abuse, or Medicaid agency in calendar year 1997. The authors found that people with co-occurring disorders were three to four times more likely to be hospitalized than clients with mental illness only and ten to 20 times more likely to be admitted than clients with a substance use disorder only.

Dilonardo J., Coffey R., Vandivort-Warren R., & Buck J. A. (2008). Datapoints: inpatient utilization for persons with co-occurring disorders. Psychiatric Services, 59(1): 14.  DOI: 10.1176/appi.ps.59.1.14. http://psychservices.psychiatryonline.org/cgi/content/full/59/1/14

Authors: Joan Dilonardo, Rosanna Coffey, Rita Vandivort-Warren, Jeffery A. Buck