Clinical characterization of late- and very late-onset first psychotic episode in psychiatric inpatients

Objectives: The goals of this study were to investigate the prevalence and initial symptoms of the late-onset schizophrenia (LOS: > 40 years) and very-late-onset schizophrenia-like psychosis (VLOSLP: > 60 years) nosological groups proposed by the International Late-Onset Schizophrenia Group. Design: This was a retrospective, cross-sectional, chart review study. Setting: The study was conducted at Centre Hospitalier Robert-Giffard (CHRG), Quebec City, Canada. Patients: The medical records of inpatients from the CHRG who presented with psychotic symptoms were analyzed. Measurements: Positive and negative symptoms were scored using the SAPS and SANS. Groups' symptoms were compared using chi(2), Fisher's exact tests, t tests, and exact Mann-Whitney tests. An exact conditional logistic regression analysis was performed to determine which clinical characteristics were the most predictive of the groups' classification. Results: Among the 1,767 unique, first-admission medical records reviewed, 23 (1.3%) inpatients developed their first psychotic symptoms at the age of 40-59 years old (LOS), and 13 (0.7%) at the age of 60 years and above (VLOSLP). LOS patients were more apathetic and presented more abnormal psychomotor activity than the VLOSLP. Persecutory delusions, auditory hallucinations, inappropriate social behavior, formal thought disorders and anhedonia were frequent in the two groups. A logistic regression model including psychomotor abnormalities was statistically relevant to predict the belonging to LOS group. Conclusion: LOS and VLOSLP are rare. Abnormal psychomotor activity can properly differentiate VLOSLP and LOS. The nosological model proposed by the International Late-Onset Schizophrenia Group is at least partially supported by the present data.