A total of 246 first-episode psychosis patients were recruited from a specialized early intervention program serving a defined epidemiological catchment area. Age of onset of psychosis (adolescence vs. adulthood) was used as the main predictor, and duration of untreated psychosis (DUP), baseline symptoms, baseline functioning, substance abuse diagnosis, medication adherence and gender were used as covariates in hierarchical regression models predicting the following positive and negative symptom remission outcomes: maximum continuous months in remission and early remission (i.e., occurring in the first three months of follow-up).
After controlling for other variables, onset of psychosis in adulthood and shorter DUP predicted early remission of positive symptoms. This effect was stronger in patients with a diagnosis of a schizophrenia-spectrum disorder. Remission of negative symptoms did not depend on age of onset, and was only predicted by baseline negative symptoms.
Patients with onset of psychosis during adulthood are more likely to achieve early positive symptom remission than those with adolescent onset. This effect might be stronger in patients with a diagnosis of a schizophrenia-spectrum disorder.