DETECTING COMORBID SUBSTANCE MISUSE AMONG PEOPLE WITH SCHIZOPHRENIA IN THE COMMUNITY - A STUDY COMPARING THE RESULTS OF QUESTIONNAIRES WITHANALYSIS OF HAIR AND URINE

Substance misuse among people with schizophrenia is thought to be comm on and to adversely affect the outcome of the illness. The shortcoming s of studies in this area include patient samples that are not epidemi ologically-based, and methods for detecting substance misuse that have serious limitations, We investigated the frequency and severity of su bstance misuse among people with schizophrenia living in the community in London. Interviews were conducted with a community-based sample of 39 people with schizophrenia aged 35 years or less, living in Inner L ondon. The assessments included ratings of psychopathology, movement d isorders and substance misuse, and co-informant histories. Urine and h air specimens were analysed for a range of substances. Urine samples w ere collected from 37 patients and hair samples were provided by 36 pa tients, Comorbid substance misuse was reported or detected in 63% of t he sample. The information elicited using a structured questionnaire f or both informants and subjects represented an under-estimate of psych ostimulant misuse and opiate misuse compared with the results obtained by hair or urine analysis. Hair analysis revealed that 12 (33%) of th ose patients providing samples had covertly abused amphetamines, opiat es or cocaine in the previous 3 months. The study demonstrated that ha ir analysis is a well-tolerated, sensitive test for substance misuse. The technique has several advantages over questionnaires and urine ana lysis for clinical and research purposes. Further applications include the assessment of comorbid substance use in particular groups of pati ents with schizophrenia, such as during first-episode or psychotic rel apse, or those with forensic problems or apparent resistance to treatm ent. (C) 1997 Elsevier Science B.V.