Rheumatoid arthritis and risk of hearing impairment: A genetic correlation and bidirectional Mendelian randomization study

Prior research has indicated a connection between rheumatoid arthritis (RA) and hearing impairment (HI), although there is disagreement among researchers. An extensive assessment of the causal relationship between RA and HI was the aim of this Mendelian randomization (MR) study. We examined summary-level data from RA and HL genome-wide association studies using inverse variance weighted (IVW) analysis. We further supplemented the results with weighted median (WM), MR-Egger, MR-RAPS, and maximum likelihood techniques. We used sensitivity analyses to check the accuracy of the MR analysis results. Genetically, higher RA substantially increases the likelihood of HI (IVW: P = 8.78 × 10-03, odds ratio (OR) = 1.014, 95% confidence interval (CI): 1.003-1.024). Sensitivity analysis reveals a consistent direction of the association using the following methods: Bayesian MR (P = 8.72 × 10-03, OR = 1.014, 95% CI: 1.004-1.025), MR robust adjustment profile score (P = 2.31 × 10-02, OR = 1.013, 95% CI: 1.002-1.024), maximum likelihood method (P = 2.70 × 10-02, OR = 1.014, 95% CI: 0.996-1.026), WM (P = 1.35 × 10-01, OR = 1.012, 95% CI: 0.996-1.029), and MR-Egger (P = 1.41 × 10-01, OR = 1.011, 95% CI: 0.996-1.027). Despite not achieving statistical significance, the WM and MR-Egger approaches offered reliable guidance. Moreover, we replicated our results on other datasets and obtained similar results (IVW: P = 8.71 × 10-03, OR = 1.016, 95% CI: 1.004-1.028), indicating the validity of our results. Our study provides evidence linking RA to a higher risk of HI. In order to gain more insight into treatments that change the disease or prevent hearing loss, audiological testing is necessary for the diagnosis and follow-up of individuals with RA.