Longitudinal effects of integrated treatment on alcohol use for persons with serious mental illness and substance use disorders

A randomized experimental design was used to assign participants to an integrated mental health and substance use treatment program or to standard hospital treatment. A multilevel, nonlinear model was used to estimate hospital treatment effects on days of alcohol use for persons with serious mental illness and substance use disorders over 18 months. The integrated treatment program had a significant effect on the rate of alcohol use at 2 months postdischarge, reducing the rate of use by 54%. Motivation for sobriety at hospital discharge, posttreatment self-help attendance, and social support for sobriety were also found to reduce the rate of use during the follow-up period. Implications for mental health treatment and aftercare support are discussed.