Association between retinal nerve fiber layer thickness and psychiatric disorders: a mendelian randomization study

Area of Science:

• Ophthalmology
• Psychiatry
• Genetics

Background:

• Retinal nerve fiber layer thickness (RNFL) is emerging as a potential biomarker for mental disorders.
• However, definitive proof of a causal relationship between RNFL and psychiatric conditions is lacking.

Purpose of the Study:

• To investigate the potential causal relationship between RNFL and major psychiatric disorders using a genetic approach.
• To explore the diagnostic potential of RNFL in mental health.

Main Methods:

• A bidirectional two-sample Mendelian randomization analysis was employed.
• Genetic data from large-scale genome-wide association studies for RNFL and three psychiatric disorders (schizophrenia, depression, bipolar disorder) were utilized.
• Inverse variance weighting and weighted median methods were primary analytical techniques, with sensitivity analyses for robustness.

Main Results:

• A significant positive causal association was found between RNFL and schizophrenia (OR=1.057, P<0.05).
• RNFL also showed a significant positive causal relationship with bipolar disorder (OR=1.025, P<0.05).
• No significant causal association was observed between RNFL and depression (P=0.74), nor were reverse causal effects found.

Conclusions:

• Genetic evidence supports a causal relationship between RNFL and schizophrenia and bipolar disorder.
• RNFL shows promise as a potential diagnostic indicator for schizophrenia and bipolar disorder.