Objectives: The temporal relationship between substance abuse and symptoms of psychosis in adolescent patients was examined.
Methods: The hospital records of all adolescent inpatients admitted to the Central Institute of Mental Health in Mannheim during the period from 1976-1997 with a first-time diagnosis of psychosis were examined retrospectively for evidence of co-morbid substance abuse.
Results: In 18 of a total of 165 psychotic patients, co-morbid substance abuse was present, whose frequency rose after 1988, with a renewed increase since 1996. Two of the 18 adolescents began taking drugs only after the appearance of the first symptoms of psychosis, in 13 others the abuse was already well established, while for the final three patients the onset of psychotic symptoms and substance abuse was congruent, occurring within the same month. A close temporal correlation between symptoms of psychosis and substance abuse was established for amphetamines (including ecstasy), LSD and excessive abuse of cannabis.
Conclusions: Substance abuse constitutes a risk factor for the development of psychoses without, however, necessarily being a direct trigger of psychosis.