Initiation of Antipsychotics During the First Year After First-Episode Psychosis: A Population-Based Study

Area of Science:

• Psychiatry
• Pharmacology
• Public Health

Background:

• Antipsychotic medication is recommended for patients experiencing their first episode of psychosis.
• Understanding real-world antipsychotic use patterns is crucial for refining clinical practice.
• This study investigates antipsychotic initiation and associated factors in first-episode psychosis patients.

Purpose of the Study:

• To describe the patterns of antipsychotic initiation within one year following a first-episode psychosis diagnosis.
• To identify socioeconomic and clinical factors associated with antipsychotic initiation in this population.

Main Methods:

• A population-based cohort study utilized linked nationwide health and population registers in Norway.
• Included 8052 individuals aged 16-45 years diagnosed with first-episode psychosis (ICD-10 F20, F22-F29) between 2011-2019.
• Antipsychotic initiation was defined by dispensing records within 365 days post-diagnosis; modified Poisson regression analyzed associated factors.

Main Results:

• 54.8% of patients initiated antipsychotic use, with initiation rates increasing from 45.5% (2012) to 62.1% (2019).
• Oral olanzapine, quetiapine, and aripiprazole were the most common initiators; long-acting injectables and clozapine were rarely used.
• Lower age, higher education, employment, hospitalization, later diagnosis, and comorbid mood/anxiety disorders were associated with initiation.

Conclusions:

• Antipsychotic prescribing patterns generally align with clinical guidelines.
• Observed socioeconomic and clinical differences in initiation may be linked to primary non-compliance or disease severity.