Sex Differences in Verbal Memory Predict Functioning Through Negative Symptoms in Early Psychosis

Area of Science:

• Neuroscience
• Psychiatry
• Cognitive Psychology

Background:

• Verbal memory (VM) is significantly impaired in first-episode psychosis (FEP) and predicts functional outcomes.
• Healthy females typically exhibit superior VM compared to males, and female patients often experience less severe illness courses.
• Understanding sex-based cognitive differences in FEP is crucial for personalized treatment strategies.

Purpose of the Study:

• To investigate if normative sex differences in VM are maintained in FEP.
• To determine if these sex differences in VM influence long-term functioning in FEP patients.
• To explore the mediating role of negative symptoms in the relationship between VM and functioning.

Main Methods:

• A cohort of 435 FEP patients and 138 healthy controls were assessed using neurocognitive batteries measuring six cognitive domains, including VM.
• Patient symptom severity (positive and negative) was evaluated at baseline.
• Patient functioning was assessed at a 1-year follow-up.

Main Results:

• FEP patients demonstrated cognitive impairments across all domains compared to controls.
• Verbal memory was the only domain showing significant sex differences, with males performing worse than females in both patient and control groups.
• Better baseline VM in female patients was associated with improved functioning at 1-year follow-up, a relationship mediated by lower baseline negative symptoms.

Conclusions:

• Normative sex differences in verbal memory are preserved in individuals with first-episode psychosis.
• Verbal memory deficits and their sex-based variations play a significant role in predicting functional outcomes in FEP.
• Sex may act as a disease-modifying variable in FEP, suggesting potential for sex-specific therapeutic interventions.