A 20-Year Follow-up of First Episode Psychosis: Longitudinal Effects of Early Treatment Strategies and Relapse

Navigating the Longitudinal Effects of Early Treatment Strategies and Relapse on Clinical, Cognitive, and Functional Outcomes: A 20-Year Follow-up of First Episode Psychosis

The study aims to address the following questions:

1. Do subgroups defined by early medication choices, relapse, and medication taken over 20 years differ in clinical, cognitive, and functional outcomes?
2. What are the long-term cognitive functioning trajectories, what factors predict these trajectories, and how do they relate to outcomes?
3. What might be the mechanisms behind medication discontinuation and poor long-term outcome, including the roles of multiple relapses and treatment resistance after first-episode psychosis?

Eligible patients will be invited to a one-time face-to-face interview. A trained research assistant will guide the participants through questions about their background, clinical symptoms, daily functioning, cognitive abilities, and psychological well-being.

Study Overview

• Status: Not yet recruiting
• Conditions: Schizophrenia

Detailed Description

Schizophrenia and related psychotic disorders are highly heterogeneous, with long-term outcomes shaped by early treatment decisions. Antipsychotic medications are effective in preventing relapse, but prolonged use carries substantial side effects, and many patients discontinue in real-world settings. Evidence on the long-term impact of early discontinuation remains scarce. This project is a 20-year follow-up of a uniquely well-characterized cohort of 178 individuals with first episode psychosis (FEP), originally enrolled in a randomized controlled trial (RCT) of antipsychotic maintenance versus discontinuation after achieving sustained remission (ClinicalTrials.gov NCT00334035). At the 10-year follow-up, over 80% of the cohort were successfully reassessed, providing rare insights into long-term outcomes (ClinicalTrials.gov NCT01926340).

Eligible participants will be re-contacted for a one-time assessment including structured clinical interviews, cognitive testing, psychosocial and qualitative measures. Retrospective case-note reviews will extract longitudinal data on relapse episodes, medication use, hospitalizations, and available laboratory results.

Data will be analyzed using latent class analysis to identify subgroups, latent growth models for cognitive trajectories, and regression approaches to test predictors and outcomes.

Ethical safeguards include re-consenting all participants, pre screening/ redacting medical records to preserve rater blinding,and strict de-identification of data. This study will be conducted in accordance with the Declaration of Helsinki and relevant institutional guidelines.

By extending this landmark cohort to 20 years, the study will provide novel evidence to guide personalized treatment decisions and inform policies on long-term antipsychotic use in psychosis.

• Study Type: Observational
• Enrollment (Estimated): 178

Contacts and Locations

• Study Contact: Name: Lai Ming Christy Hui, PhD; Phone Number: 852-22554486; Email: christy@lmhui.com

Study Locations

• China
  • Hong Kong, China
    • The University of Hong Kong

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Trained research assistants will approach active patients at their upcoming psychiatric out-patient consultations at the hospitals to introduce the follow-up study and to obtain written informed consent.

Description

Participants were individuals who previously participated in a randomized controlled trial investigating medication continuation/discontinuation on relapse during first episode psychosis (ClinicalTrials.gov NCT00334035). The trial included specific inclusion and exclusion criteria, detailed as follows:

Inclusion Criteria:

• A diagnosis of schizophrenia or non-affective psychosis (schizophreniform disorder, schizoaffective disorder, brief psychotic disorder, or psychosis not otherwise specified) (DSM-IV)
• Aged 18 to 65 years at the time of original enrolment
• Had been treated with antipsychotic drugs for at least 12 months
• No history of relapse or exacerbation or had to be asymptomatic (free of positive symptoms of psychosis) at study entry.

Exclusion Criteria:

• A diagnosis of drug-induced psychosis
• Current treatment with clozapine, with mood stabilizing medications (lithium, valproate or carbamazepine) or with depot medication
• Had high risk of suicide or violence
• Inability to provide informed consent at recruitment

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Early maintenance treatment group; Drug (quetiapine, 400mg/d) during the 12-month randomized phase of the study
Early discontinuation group; Drug (placebo) during the 12-month randomized phase of the study

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Long-term Clinical Outcome	Poor clinical outcome is defined categorically as any of: Persistent positive symptoms of psychosis, requirement for clozapine, or death from suicide. A good clinical outcome is defined as meeting none of the above criteria	From enrollment to 20-year follow-up

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Long-term Overall Functioning	Evaluated using the Social and Occupational Functioning Assessment Scale (SOFAS). Lower scores reflect poorer functioning in social and work-related domains, irrespective of psychopathology	Assessed for 6 months preceding the follow-up assessment
Long-term Role Functioning	Evaluated using the Role Functioning Scale (RFS), which assesses functioning across key domains including work productivity, independent living and self-care, relationships with immediate social networks, and relationships with extended social networks. Higher scores indicate better functioning	Assessed for 6 months preceding the follow-up assessment
Overall Clinical Status	Evaluated using the Clinical Global Impression (CGI) scale, a measure of global illness severity and change in condition over time. The scale comprises Severity and Improvement ratings, with higher scores indicating more severe current illness and worsened clinical status over the past six months, respectively	Within 6 months previous to the follow-up assessment
Long-term Psychopathology	Evaluated using the Positive and Negative Syndrome Scale (PANSS), which evaluates self-reported symptom severity across positive symptoms, negative symptoms, and general psychopathology domains. Higher scores indicate greater symptom severity	Within 6 months previous to the follow-up assessment
Long-term Positive Symptoms	Evaluated using the Scale for the Assessment of Positive Symptoms (SAPS), which evaluates self-reported symptom severity across domains including hallucinations, delusions, bizarre behavior, and formal thought disorder. Higher scores indicate greater symptom severity	Within 6 months previous to the follow-up assessment
Long-term Negative Symptoms	Evaluated using the Scale for the Assessment of Negative Symptoms (SANS), which evaluates self-reported domains including affective flattening, alogia, avolition-apathy, anhedonia-asociality, and attention-related impairment. Higher scores indicate greater symptom severity	Within 6 months previous to the follow-up assessment
Medication Adherence	Evaluated using the Medication Compliance Questionnaire (MCQ), which includes subscales assessing self-reported medication-taking behaviors and medication-related attitudes. Higher scores indicate better medication adherence and more positive attitudes toward medication	Within 1 month previous to the follow-up assessment
Semantic Memory and Executive Function	Participants engage in a Verbal Fluency Task, where they will be asked to name as many animals as possible within one minute. Outcomes include the counts of correct, repeated, and incorrect responses. Higher numbers of correct responses indicate better cognitive functioning	Assessed at the follow-up assessment
Verbal Working Memory	Participants engage in a Letter-Number Span Test, where they will be asked to repeat sequences of numbers and letters presented verbally by research staff in forward or backward order. The number of items to be recalled gradually increases throughout the task. Higher scores indicate better working memory performance	Assessed at the follow-up assessment
Visual Working Memory and Spatial Processing	Participants engage in a Visual Patterns Test, where they will be required to remember and reproduce visually presented geometric patterns after brief exposure. Higher scores indicate better visual memory performance	Assessed at the follow-up assessment
Stressful Life Events	The Stressful Life Events (SLE) questionnaire evaluates the number of significant life events experienced (e.g., loss of a loved one, severe financial problems) and the associated level of distress reported by participants. Higher scores indicate greater exposure to stressful events and/or higher levels of distress	Within 6 months previous to the follow-up assessment
Health-Related Quality of Life	Evaluated using the 36-Item Short Form Health Survey (SF-36), which includes two subscales assessing physical health and mental health across multiple domains (e.g., physical ability in fulfilling role-related tasks, bodily pain, and emotional well-being). Higher scores indicate better perceived health status and quality of life	Varies according to the individual questionnaire items, ranging from the past 4 weeks to the past 12 months prior to the follow-up assessment

Collaborators and Investigators

• Sponsor: The University of Hong Kong
• Collaborators: Research Grants Council, Hong Kong

Publications and helpful links

General Publications

• Hui CLM, Honer WG, Lee EHM, Chang WC, Chan SKW, Chen ESM, Pang EPF, Lui SSY, Chung DWS, Yeung WS, Ng RMK, Lo WTL, Jones PB, Sham P, Chen EYH. Long-term effects of discontinuation from antipsychotic maintenance following first-episode schizophrenia and related disorders: a 10 year follow-up of a randomised, double-blind trial. Lancet Psychiatry. 2018 May;5(5):432-442. doi: 10.1016/S2215-0366(18)30090-7. Epub 2018 Mar 15.
• Chen EY, Hui CL, Lam MM, Chiu CP, Law CW, Chung DW, Tso S, Pang EP, Chan KT, Wong YC, Mo FY, Chan KP, Yao TJ, Hung SF, Honer WG. Maintenance treatment with quetiapine versus discontinuation after one year of treatment in patients with remitted first episode psychosis: randomised controlled trial. BMJ. 2010 Aug 19;341:c4024. doi: 10.1136/bmj.c4024.

Study record dates

Study Major Dates

• Study Start (Estimated): May 21, 2026
• Primary Completion (Estimated): December 31, 2028
• Study Completion (Estimated): December 31, 2028

Study Registration Dates

• First Submitted: May 13, 2026
• First Submitted That Met QC Criteria: May 28, 2026
• First Posted (Actual): June 1, 2026

Study Record Updates

• Last Update Posted (Actual): June 1, 2026
• Last Update Submitted That Met QC Criteria: May 28, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Schizophrenia; 20-year follow up
• Additional Relevant MeSH Terms: Schizophrenia Spectrum and Other Psychotic Disorders; Mental Disorders; Schizophrenia
• Other Study ID Numbers: HKU/HA_HKW_IRB_UW25-571

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: The data will be made available upon reasonable request, subject to ethical considerations and data privacy protections.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No