Rheumatoid arthritis and diabetic retinopathy: A two-sample Mendelian randomization study

Area of Science:

• Ophthalmology
• Rheumatology
• Genetics

Background:

• Diabetic retinopathy (DR) is a leading cause of blindness.
• The relationship between rheumatoid arthritis (RA) and DR is debated, with contradictory findings and unclear pathogenic links.
• Existing research presents paradoxes, necessitating a robust investigation into RA's influence on DR development.

Purpose of the Study:

• To assess the causal association between rheumatoid arthritis (RA) and the development of diabetic retinopathy (DR).
• To clarify the influence of RA on DR pathogenesis using genetic data.
• To provide evidence-based recommendations for managing DR risk in RA patients.

Main Methods:

• Employed a 2-sample Mendelian randomization (MR) approach.
• Utilized genome-wide association study (GWAS) data for DR (n=190,594) and RA (n=58,284).
• Applied Inverse Variance Weighted (IVW), MR-Egger, and Weighted Median methods, with sensitivity analyses (pleiotropy, heterogeneity, leave-one-out) to ensure robustness.

Main Results:

• Identified 83 relevant single nucleotide polymorphisms (SNPs).
• The IVW method indicated a positive causal association between RA and increased DR risk (OR=1.06, 95% CI: 1.04-1.23).
• MR-Egger and Weighted Median methods corroborated the findings; sensitivity analyses confirmed robustness and minimal bias.

Conclusions:

• Confirmed a significant positive causal link between rheumatoid arthritis and diabetic retinopathy.
• Emphasized the importance of proactive retinal screening and preventive measures for diabetic patients with RA.
• The findings suggest a need for integrated care strategies to mitigate DR risk in the RA population.