Exploring the clinical relevance of a dichotomy between affective and non‐affective psychosis: Results from a first‐episode psychosis cohort study

Aim Defining diagnosis is complex in early psychosis, which may delay the introduction of an appropriate treatment. The dichotomy of affective and non‐affective psychosis is used in clinical setting but remains questioned on a scientific basis. In this study, we explore the clinical relevance of this dichotomy on the basis of clinical variables in a sample of first‐episode psychosis patients. Method We conducted a prospective study in a sample of 330 first‐episode psychosis treated at an early intervention program. Affective and non‐affective psychosis patients were compared on premorbid history, baseline data, outcomes and course of symptoms over the 3 years of treatment. Results Affective psychosis patients (22.42%) were more likely to be female, and had a shorter duration of untreated psychosis. The longitudinal analyses revealed that positive symptoms remained higher over the entire follow‐up in the non‐affective sub‐group. A higher degree of variability of manic symptoms and a significantly better insight after 6 months were observed in the affective sub‐group. No difference was observed regarding depressive and negative symptoms. At discharge, only the environmental quality of life and insight recovery were better in affective psychosis. Conclusions Our study suggests that despite marginal differences at baseline presentation, these sub‐groups differ regarding outcome, which may require differentiation of treatment and supports the utility of this dichotomy.