PATTERNS OF CURRENT AND LIFETIME SUBSTANCE USE IN SCHIZOPHRENIA

A structured interview and standardized rating scales were used to ass ess a sample of 194 outpatients with schizophrenia in a regional Austr alian mental health service for substance use, abuse, and dependence. Case manager assessments and urine drug screens were also used to dete rmine substance use. Additional measurements included demographic info rmation, history of criminal charges, symptom self-reports, personal h opefulness, and social support. The sample was predominantly male and showed relative instability in accommodations, and almost half had a h istory of criminal offenses, most frequently drug or alcohol related. The 6-month and lifetime prevalence of substance abuse or dependence w as 26.8 and 59.8 percent, respectively, with alcohol, cannabis, and am phetamines being the most commonly abused substances. Current users of alcohol comprised 77.3 percent and current users of other nonprescrib ed substances (excluding tobacco and caffeine) comprised 29.9 percent of the sample. Rates of tobacco and caffeine consumption were high. Th ere was a moderate degree of concordance between case manager determin ations of a substance-use problem and research diagnoses. Subjects wit h current or lifetime diagnoses of substance abuse/dependence were pre dominantly young, single males with higher rates of criminal charges; however, there was no evidence of increased rates of suicide attempts, hospital admissions, or daily doses of antipsychotic drugs in these g roups compared with subjects with no past or current diagnosis of subs tance abuse or dependence. Subjects with a current diagnosis of substa nce use were younger at first treatment and currently more symptomatic than those with no past or current substance use diagnosis. The pictu re emerging from this study replicates the high rate of substance abus e in persons with schizophrenia reported in North American studies but differs from the latter in finding a slightly different pattern of su bstances abused (i.e., absence of cocaine), reflecting relative differ ences in the availability of certain drugs.