Complications of severe mental illness related to alcohol and drug use disorders.

In this chapter we review research on the relationships between substance use disorder and 11 domains of adjustment for people with severe mental illness. Studies are divided into correlational research and prospective, longitudinal research, with greater weight given to those in the latter category. The weight of the evidence indicates that substance abuse severely complicates severe mental illness in the following domains: relapse of psychiatric illness, hospitalization, disruptive behavior, familial problems, residential instability, decreased functional status, HIV infection, and medication noncompliance. We discuss the limits of causal inference in these studies and the possible mechanisms that relate substance abuse to various complications.