Diagnostic stability 10 years post first episode psychosis-findings from the aetiology and ethnicity in the study of schizophrenia and other psychoses (AESOP) cohort

Abstract

Background: This project set out to examine the stability of diagnoses following first episode psychosis at 10 year follow up in an epidemiological cohort, and to examine for patterns of diagnostic change. Methods: 543 cases in this study were part of the AESOP cohort identified in London and Nottingham between 1997 and 1999. 501 (92%) cases had a diagnosis available at baseline and 10 years and are included in the analysis. Diagnoses were made by consensus from all available information at baseline and follow up (41.8% were re-interviewed at follow up) for the ICD 10 DCR and DSM IV classification systems. Prospective Consistency (PC), the proportion of patients given a diagnosis at baseline who retain it at follow up, measures consistency of diagnosis over time. Retrospective Consistency (RC), patients receiving the same diagnosis at baseline and follow up as a proportion of total number of patients receiving that specific diagnosis at follow up, measures migration in to a category over time. PC and RC were calculated for each diagnostic category. Results: Please see table for results. Conclusion: Schizophrenia and Bipolar Affective Disorder show the highest diagnostic stability consistent with prior research (high PC = high RC). Delusional Disorder appears to be an early attenuated form of more florid illness (PC