Estimating the cost impact of three dual diagnosis treatment programs.

Specialized intervention programs for people with concurrent severe mental illness and substance abuse reduce the total costs of care. Compared to baseline, cost savings of over 40% were achieved by 18 months, primarily due to significant reductions in the use of acute and subacute mental health services and despite an increase in outpatient mental health services. There also was an observable impact on cost reductions in medical and criminal justice services without an increase in family costs over the same time period.