Inflammatory arthritis and eye diseases: a Mendelian randomization study.

Area of Science:

• Ophthalmology
• Rheumatology
• Genetics

Background:

• Inflammatory arthritis encompasses conditions like rheumatoid arthritis (RA), ankylosing spondylitis (AS), psoriatic arthritis (PsA), and juvenile idiopathic arthritis (JIA).
• These conditions can have systemic effects, potentially impacting ocular health, but causal links require robust investigation.

Purpose of the Study:

• To investigate the potential causal relationships between genetically predicted inflammatory arthritis and specific eye diseases.
• To determine if inflammatory arthritis increases the risk for disorders of the sclera, cornea, iris, and ciliary body (DSCIC) and disorders of the choroid and retina (DCR).

Main Methods:

• Utilized two-sample Mendelian randomization analysis with summary data from large genome-wide association studies.
• Employed UK Biobank and FinnGen Biobank data to identify genetically predicted cases of inflammatory arthritis and eye diseases.
• Applied inverse-variance weighting (IVW) as the primary analysis, with MR-Egger, weighted median, and MR-PRESSO for sensitivity analyses.

Main Results:

• Rheumatoid arthritis (RA) showed a causal effect on DSCIC and DCR.
• Ankylosing spondylitis (AS) and psoriatic arthritis (PsA) were causally associated with an increased risk of DSCIC.
• Disorders of the sclera, cornea, iris, and ciliary body (DSCIC) were found to increase the risk of juvenile idiopathic arthritis (JIA).

Conclusions:

• This study provides genetic evidence supporting causal links between RA, AS, and PsA with an increased risk of DSCIC.
• A significant causal association was identified between RA and DCR.
• The findings highlight a bidirectional relationship, with DSCIC also increasing the risk for JIA.