A prospective study of severe mental disorder in Afro-Caribbean patients.

Several previous studies have reported increased rates of schizophrenia among Afro-Caribbean immigrants, although doubt has been cast upon the value of case-note diagnoses and retrospective case-finding. A prospective study was therefore undertaken, including all patients of Afro-Caribbean ethnic origin with a first onset psychosis presenting to the psychiatric services from a defined catchment area. Utilizing several diagnostic classifications, rates for schizophrenia were found to be substantially increased in the Afro-Caribbean community, and especially in the 'second generation' British born. Mode of onset and symptom profiles of psychoses suggest that atypical syndromes, and by implication 'misdiagnoses', do not account for reported higher rates of schizophrenic illness in these patients.