Mendelian randomization studies in ankylosing spondylitis: A systematic review.

Area of Science:

• Genetics
• Epidemiology
• Immunology

Background:

• Ankylosing spondylitis (AS) is linked to various comorbidities.
• Observational studies struggle to establish causality due to confounding factors.
• Mendelian randomization (MR) provides a robust method to infer causal relationships.

Purpose of the Study:

• To systematically review Mendelian randomization (MR) studies investigating causal risk factors for ankylosing spondylitis (AS).
• To identify specific exposures, such as health behaviors, comorbidities, and serum markers, causally associated with AS.
• To inform potential health management strategies for AS.

Main Methods:

• Systematic literature search of PubMed, Web of Science, and Cochrane databases for MR studies on AS up to May 2024.
• Extraction of study details including exposures, outcomes, data sources, and statistical findings (ORs, CIs, p-values).
• Quality assessment of included studies using the Critical Appraisal Skills Program (CASP) checklist.

Main Results:

• A total of 42 MR studies related to AS were reviewed.
• Physical activity, inflammatory bowel disease, and specific intestinal flora were identified as causally associated with AS.
• These factors increase the risk of AS and are linked to several comorbidities.

Conclusions:

• Mendelian randomization is a powerful tool for establishing causal links in AS research.
• Inflammatory bowel disease and specific intestinal flora are confirmed as significant risk factors for AS.
• Robust MR findings can guide comprehensive health management strategies for patients with AS.