Background: This article first examines the epidemiology of nonaffective acute remitting psychosis with respect to variation in incidence by sex and sociocultural setting. Second, it examines whether nonaffective acute remitting psychosis can be epidemiologically differentiated from schizophrenia.
Methods: The data were drawn from the World Health Organization Determinants of Outcome Study. Sex-specific incidence rates were obtained for two sites in the developing-country setting and for six sites in the industrialized-country setting.
Results: For nonaffective acute remitting psychosis, the incidence in men was about one-half the incidence in women, and the incidence in the developing-country setting was about 10-fold the incidence in the industrialized-country setting. These associations with sex and with setting were sharply distinct from those of schizophrenia.
Conclusion: The epidemiologic patterns of this form of psychosis may be distinct from those of schizophrenia and could yield clues to its causes.