The psychosis continuum in the general population: findings from the Sao Paulo Epidemiologic Catchment Area Study

Abstract

The aim of the study was to examine the psychosis continuum in a Latin-American community setting. Data were from the Brazilian Sao Paulo Epidemiologic Catchment Area Study, a cross-sectional survey conducted in two boroughs of the city of Sao Paulo. The Composite International Diagnosis Interview (version 1.1) was applied to a probabilistic sample of 1,464 adults, who were interviewed in their household, in order to identify the presence of psychotic symptoms. A subsample was assessed with Schedules for Clinical Assessment in Neuropsychiatry interview. We described the occurrence of psychotic symptoms, categorized into subgroups according to their clinical impact, disability, and help-seeking behavior. The correlation of socio-demographic variables, depressive symptoms, and alcohol and substance use disorders with those psychotic subgroups was analyzed. Polychotomic logistic regression tested the associations between subgroups of psychosis (clinical and subclinical) and the correlates. Of the total sample, 38.0% presented at least one lifetime psychotic symptom, 1.9% met the criteria for an ICD-10 diagnosis of non-affective psychosis, 5.4% presented clinically relevant psychotic symptoms, and 30.7% endorsed clinically non-relevant symptoms. The most common psychotic symptom was delusion with a plausible explanation (in 18.6%). The presence of any psychiatric diagnosis was associated with the presence of psychotic symptoms (OR range, 1.9-8.9). Subclinical psychosis subgroups were found to be associated with the 18-24 year age bracket, chronic depressive mood, and alcohol use disorder. Our results support the concept of a psychosis continuum in Latin-American populations, suggesting that different risk factors influence their manifestation across the continuum.