Educational attainment increases the risk of developing allergic rhinitis/eczema: a Mendelian Randomization Study based on genome-wide association studies in European patients

Objective　Observational studies have shown that allergic diseases such as allergic rhinitis and eczema are more common in individuals with a higher educational attainment, but the relationship between educational attainment and the risk of allergic diseases is not clear. Thus, this study aimed to determine the causal relationship between educational attainment and the risk of allergic rhinitis/eczema. Methods　Two-sample Mendelian randomization (MR) analyses were performed using the summary data of genome-wide association studies (GWAS), which involved 293,723 participants (educational attainment) from the Social Science Genetics Association Consortium (SSGAC) and 462,013 participants (allergic rhinitis/eczema) from the UK Biobank. Results　In the univariable MR analyses, an increase in the duration of education by 1 year or 1 standard deviation (SD) (3.71 years) was associated with a 4.40% or 17.11% higher risk, respectively, of allergic rhinitis/eczema (odds ratio [OR] = 1.044, 95% confidence interval [CI] = 1.020–1.069, P < 0.001; OR = 1.17, 95% CI = 1.07–1.28, P < 0.001, respectively). In the reverse MR analysis, we found little evidence that allergic rhinitis/eczema affected educational attainment (OR = 1.020, 95% CI = 0.927–1.023, P = 0.683). Conclusion　This study suggests that there is a positive causal relationship between educational attainment and the risk of allergic rhinitis/eczema, which means that educational attainment can increase the occurrence of allergic rhinitis/eczema.