Trajectories and Antecedents of Treatment Response Over Time in Early-Episode Psychosis

Abstract

Little is known about the extent of heterogeneity of symptomatology in treated early-onset psychosis. The current study aims to quantify the extent of heterogeneity in trajectories of treated symptom severity in early-episode psychosis and their antecedents. Data were from 491 persons with early-episode psychosis from a clinical trial of haloperidol and risperidone. Positive and Negative Syndrome Scale (PANSS) administrations were used to measure symptom severity trajectories for (a) rapid treatment response scores over 4 weeks and (b) medium-term course over 24 weeks. Baseline antecedents included sex, Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, diagnosis, age of onset, the Premorbid Adjustment Scale, and a cognitive test battery. Symptom severity trajectories were calculated with mixed mode latent class regression modeling from which groups were derived. Five groups based on PANSS scores over time were identified. Over 4 weeks, 3 groups with varied baseline PANSS scores (54-105) did not surpass 30% PANSS improvement. Another group improved and then was stable (n = 76,15.3%), and another showed marked improvement (n = 94,18.9%). Logistic regression showed that membership in the best response trajectory was associated with not having a diagnosis of schizophrenia, good premorbid functioning, and higher cognitive functioning, whereas membership in the poor response trajectory was associated with earlier age of onset and poorer cognitive functioning. Amelioration generally characterizes treated symptom severity. Age of onset, diagnosis, cognitive functioning, and premorbid functioning have prognostic value in predicting treatment response trajectories.