The Association between Myopia and Anxiety: A Bidirectional 2-Sample Mendelian Randomization Study.

OBJECTIVE

To investigate whether there is a causal relationship between generalized anxiety disorder (GAD) and myopia.

DESIGN

A bidirectional 2-sample Mendelian randomization (MR) analysis.

SUBJECTS: For the forward MR, 11 single nucleotide polymorphisms (SNPs) associated with GAD were obtained from the FinnGen Research (5280 cases and 368 054 controls; European). For reverse MR, 253 SNPs associated with mean spherical equivalent (MSE) were derived from the UK Biobank (95 619 participants; European).

METHODS

Summary-level data from the 2 genome-wide association studies were used to conduct bidirectional MR analyses. Four MR methodologies-inverse variance weighted (IVW), MR-Egger regression, weighted median, and weighted mode-were employed, with IVW serving as the primary analysis. Sensitivity analyses, including MR-Egger intercept and heterogeneity Q test, were performed.

MAIN OUTCOME MEASURES: The outcomes of the forward and reverse MR analyses were MSE and GAD, respectively.

RESULTS

This study demonstrated a significant causal effect of GAD and myopia, suggesting individuals with GAD are at an elevated risk of more myopic MSE (IVW: β = -0.138; 95% confidence interval [CI] -0.221 to -0.056, P = 0.001). Conversely, we did not find evidence to support a causal effect of myopia on GAD (IVW: β = -0.017; 95% CI -0. 051 to -0.016, P = 0.308). Sensitivity analyses revealed no evidence of genetic confounding to bias the estimate of causal effect.

CONCLUSIONS

Our study demonstrates a significant causal relationship between GAD and a more myopic MSE, though the effect size was relatively small. These findings could be taken into consideration while implementing mental health interventions in children.

FINANCIAL DISCLOSURES: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.