Exploring causal associations between autoimmune diseases and hearing loss: a mendelian randomization study

Area of Science:

• Genetics and Medicine
• Autoimmune Diseases
• Hearing Loss

Background:

• The causal relationship between autoimmune diseases (ADs) and hearing loss (HL) is not well understood.
• Genetic predispositions may play a role in the development of HL in individuals with ADs.

Purpose of the Study:

• To investigate the potential causal effects of ADs on various types of HL using a Mendelian Randomization (MR) approach.
• To identify specific ADs that are genetically associated with an increased risk of hearing loss.

Main Methods:

• Mendelian Randomization (MR) analysis utilizing Single Nucleotide Polymorphisms (SNPs) from Genome-Wide Association Studies (GWAS) as instrumental variables for eight ADs.
• Outcome data included sensorineural hearing loss (SNHL), conductive hearing loss (CHL), mixed hearing loss (MHL), and sudden idiopathic hearing loss (SIHL).
• Statistical methods included Inverse Variance Weighted (IVW), MR-Egger, weighted median, and weighted mode, with assessments for heterogeneity and pleiotropy.

Main Results:

• Nine significant associations between ADs and HL were identified, including associations between Multiple Sclerosis (MS) and Sudden Idiopathic Hearing Loss (SIHL), Ankylosing Spondylitis (AS) and various HL types, Systemic Lupus Erythematosus (SLE) and CHL, Ulcerative Colitis (UC) and MHL, and Crohn's Disease (CD) and CHL/SIHL.
• An association between AS and SNHL remained significant after outlier removal, with resolved heterogeneity and pleiotropy.
• No significant heterogeneity or pleiotropy was observed for the other identified associations.

Conclusions:

• This MR study provides evidence for significant genetic associations between several autoimmune diseases and hearing loss.
• The findings highlight the importance of considering hearing loss screening and management in patients diagnosed with autoimmune diseases.