Investigating the association between schizophrenia and distance visual acuity: Mendelian randomisation study

Area of Science:

• Psychiatric Genetics
• Ophthalmology
• Biostatistics

Background:

• Individuals with schizophrenia exhibit higher rates of visual impairment.
• The causal relationship between visual acuity and schizophrenia remains unclear.

Purpose of the Study:

• To investigate the potential causal link between genetically predicted poor distance acuity and schizophrenia.
• To examine if genetically predicted schizophrenia causally influences visual acuity.

Main Methods:

• Utilized bidirectional, two-sample Mendelian randomization.
• Employed large-scale genetic summary statistics from European and East Asian ancestry samples (N ≈ 14,000–500,000).
• Applied inverse variance-weighted methods and sensitivity analyses for result validation.

Main Results:

• Found no significant evidence that poor distance acuity causally increases schizophrenia risk.
• Demonstrated a significant association between genetically predicted schizophrenia and poorer visual acuity in European samples (mean difference in logMAR: 0.024).
• Observed a similar trend in East Asian samples, though with less statistical precision.

Conclusions:

• Schizophrenia is a potential causal risk factor for diminished visual acuity.
• Conversely, poor visual acuity does not appear to be a causal factor for schizophrenia.
• Emphasizes the importance of visual care for schizophrenia patients and refutes visual impairment as a schizophrenia prevention strategy.