Diagnostic shift in adolescents with first episode psychosis: findings from the 2-year follow-up of the "Parma Early Psychosis" program.

Purpose: Diagnostic stability for people with First Episode Psychosis (FEP) is essential for treatment, but it remains poorly investigated, especially in adolescents and within a prospective design. The aims of this research were: (a) to examine diagnostic change in Italian adolescents with FEP treated within an "Early Intervention in Psychosis" program during a 2-year follow-up period and (b) to investigate any sociodemographic and clinical predictors at baseline.

Methods: At baseline, 66 adolescents with FEP was recruited. Their primary diagnosis was formulated both at baseline and at the end of follow-up. At presentation, FEP adolescents completed the Health of the Nation Outcome Scales for Children and Adolescents (HoNOSCA). As for diagnostic stability, the Kappa statistic was calculated. The associations of diagnostic change with baseline clinical and sociodemographic features were analyzed using a logistic model with the diagnostic shift as dependent variable. A propensity score was finally calculated based on logistic analysis results.

Results: 38 (57.6%) FEP adolescents changed their opening diagnosis. The highest prospective diagnostic stability was for initial diagnosis of schizophrenia (95.4%) and affective spectrum psychoses (75%). Diagnostic instability was high for opening diagnosis of psychosis not otherwise specified, brief psychosis and schizophreniform disorder (100%). The best predictors of diagnostic change were fewer years of education, shorter duration of untreated psychosis and higher baseline levels of psychiatric symptoms.

Conclusion: Diagnostic stability is crucial for treatment and clinical decision making. Addressing instability in FEP diagnoses is an important challenge for future diagnostic development in early psychosis, especially in adolescence.