SCHIZOPHRENIA AND PSYCHOSTIMULANT ABUSE - A REVIEW AND REANALYSIS OF CLINICAL-EVIDENCE

The authors selected articles from those published between 1975 and 19 94 that specifically documented psychostimulant abuse in patients dete rmined to be schizophrenic according to recent and relatively uniform diagnostic criteria. These articles indicated that the incidence of ps ychostimulant abuse in schizophrenics is 2-5 times higher than that of the general public. Additionally, unlike the decline in stimulant use seen in older adults in the general population, high rates of abuse a ppeared to be maintained in schizophrenics. Although the incidence of abuse in this group was high, comparisons of abuse rates generated by self-report with those obtained by urinalysis indicated that the frequ ency of abuse is being underestimated by 15-21%. Potential factors con tributing to stimulant abuse in schizophrenics, including the disease process, and the influence of chronic neuroleptic medication, were eva luated. Results indicated that the incidence of psychostimulant abuse was neither a common property of psychiatric patients, nor exclusive t o schizophrenics, but appeared to be related to chronic treatment with neuroleptic drugs. Symptom severity was generally similar in schizoph renic abusers and non-abusers, which also suggested a degree of indepe ndence from the disease process. In a majority of the studies surveyed , abuse of stimulants followed disease onset. It was also found that s timulant abuse was associated with marked increases in hospitalization in this patient group, including those known to be neuroleptic medica tion compliant. Possible explanations for the initiation and maintenan ce of psychostimulant abuse in schizophrenics are discussed in relatio n to clinical and preclinical evidence on drug addiction.