Dsm-5-Defined Attenuated Psychosis Syndrome and Conversion to Full-Scale Schizophrenia Spectrum Disorders: An Institution-Wide Retrospective Review

Background The objective of the study was to determine if DSM-5–defined attenuated psychosis syndrome (APS) could identify individuals with prodromal psychosis and predict conversion to schizophrenia spectrum disorders at a rate similar to that observed in previous studies that utilized structured interviews and specialized rating scales. Methods A retrospective review of patients’ medical records was used to identify individuals meeting diagnostic criteria for the APS, followed by further evaluation 2 to 3 years after the initial diagnosis, to determine if they converted to schizophrenia spectrum disorders. Results then were compared with previous studies. Results Of our study population, 43.4% converted to schizophrenia or schizoaffective disorder 2 to 3 years after initial diagnosis of APS. Comparison at the 3-year mark indicated that there was no significant difference between our observed rates and previously published conversion rates ( P = .066). Three covariates were found to increase significantly the rates of conversion when added to the APS criteria: Cannabis use ( P = .048), lack of previous Axis I diagnosis ( P = .005), and lack of previous treatment with psychotropic medications ( P = .009). Conclusions APS accurately predicts conversion to full-scale schizophrenia spectrum disorders at a rate similar to that observed in previous studies using structured interviews and specialized rating scales.