Schizophrenia and substance abuse: the interface.

1. Starting from the hypothesis that schizophrenia is not a defined disease entity but may be part of a variety of "anomalous need disorders", the goal of our study (a sample of 30 patients) was to establish whether schizophrenia and substance abuse are caused by completely different factors or, on the contrary, are generated by similar processes. 2. The prevailing tendency to substance abuse and of a depression phase, that may be hardly elaborated, in this sample of patients with positive symptoms led us to a common denominator of the two disorders: a lacking structure where the symptom would substitute the defective element.