DOES SUBSTANCE-ABUSE RESULT IN SCHIZOPHRENIA

The high comorbidity of schizophrenia and substance abuse raises the q uestion of a causal relationship between the two disorders. Clarifying the temporal sequence of their onsets can shed light on this issue. F or this purpose, onset and course of schizophrenic symptoms and of alc ohol and drug abuse were retrospectively investigated within the ABC S chizophrenia Study in a representative first-episode sample of 232 sch izophrenic patients. The rates of alcohol abuse (24%) and of drug abus e (14%) were twice the rates compared to the general population but sc hizophrenic patients seemed to have started substance abuse later than the control group. Male sex and early symptom onset were major risk f actors. At all important landmarks during the early course of schizoph renia, drug-abusers were younger than alcohol-abusers who were younger than non-abusers. Alcohol abuse usually started during the prodromal phase, i.e., after the first sign of schizophrenia but before the firs t positive symptom. Drug abuse emerged before the first symptom in one third, simultaneously with it in another third, and during the prodro mal phase in the last third of patients. Drug abuse significantly prec eded the psychotic phase. The hypothesis that substance abuse causes s chizophrenia thus is not generally supported. Findings on symptomatolo gy illustrate the problems substance-abusing schizophrenics pose from early on with dissocial behaviors and preccupation with magical ideas but without a specific positive or negative subsyndrome.