Associations between plasma fatty acid concentrations and schizophrenia: a two-sample Mendelian randomisation study

Area of Science:

• Nutritional Neuroscience
• Psychiatric Genetics
• Metabolic Disorders

Background:

• Individuals with schizophrenia often exhibit lower omega-3 and omega-6 fatty acid levels.
• Existing evidence for the efficacy of fatty acid supplementation in schizophrenia is limited.

Purpose of the Study:

• To investigate the potential causal relationship between omega-3 and omega-6 fatty acid concentrations and schizophrenia risk.
• To explore the differential effects of short-chain and long-chain fatty acids on schizophrenia.

Main Methods:

• A two-sample Mendelian randomization study utilizing publicly available genome-wide association study (GWAS) summary data.
• Inverse variance weighted (IVW) method, weighted median, weighted mode, and MR-Egger regression for robust analysis.
• Sensitivity analyses including FADS gene cluster and ELOVL2 gene locus investigations, and multivariable MR to assess independent effects.

Main Results:

• Long-chain omega-3 and omega-6 fatty acids were associated with a reduced risk of schizophrenia (e.g., DHA OR 0.83).
• Short-chain omega-3 and omega-6 fatty acids showed a potential increased risk (e.g., ALA OR 1.07).
• Protective effects of DHA remained significant after adjusting for other lipids.

Conclusions:

• Findings support a protective role for long-chain fatty acids (LC-PUFAs) in schizophrenia.
• Potential impaired conversion of short-chain to long-chain fatty acids in schizophrenia warrants further investigation.
• Future research should explore LC-PUFA supplementation or dietary interventions for schizophrenia prevention.