[Prevalence of psychosis/substance abuse comorbidity. Clinical-epidemiological findings from different treatment settings in a large German city].

Comorbid substance use disorders in schizophrenia are of high clinical relevance, because they are common and they are mostly associated with an unfavourable long-term prognosis. Whereas the clinical impression suggests a continuous increase of substance use disorders in patients with schizophrenia over the last 10-20 years, results from epidemiological studies have been inconsistent. The aim of the present investigation was to study the prevalence of substance use disorders within a large sample of patients with schizophrenia in a large German city (Cologne).