Effect of Red Yeast Rice on Cognitive Functioning in Schizophrenia: Data From a Pilot Study

Area of Science:

• Neuroscience
• Psychiatry

Background:

• Cognitive deficits (CDs) are a significant issue in schizophrenia, impacting patient outcomes and daily functioning.
• Redox imbalance is a suspected contributor to schizophrenia-related CDs.
• Red yeast rice (RYR) possesses antioxidant and anti-inflammatory properties, suggesting potential therapeutic benefits.

Purpose of the Study:

• To investigate the efficacy of RYR supplementation in improving cognitive deficits in schizophrenia outpatients.
• To assess the impact of RYR on specific neuropsychological tests and clinical symptoms.

Main Methods:

• A 12-week study involving 35 schizophrenia outpatients on stable antipsychotic treatment.
• Participants received RYR at 200 mg/day (11.88 mg monacolin K).
• Cognitive function was assessed using the Wisconsin Card Sorting Test (WCST), Verbal Fluency, and Stroop task; clinical symptoms were evaluated with the Brief Psychiatric Rating Scale.

Main Results:

• RYR supplementation significantly reduced "perseverative errors" and "total errors" on the WCST (P = 0.015, P = 0.017).
• Significant improvement was observed in the phonemic fluency test (P = 0.008).
• No significant changes in clinical symptoms or adverse effects were reported, though effect sizes for cognitive improvements were small.

Conclusions:

• RYR supplementation shows potential as a strategy to address cognitive deficits in schizophrenia.
• Limitations include an open design, lack of a control group, small sample size, and short observation period.
• Further randomized, placebo-controlled studies are necessary to validate RYR's role in treating schizophrenia-related cognitive deficits.