Causal effects of educational attainment on respiratory diseases

This study aimed to assess the causal relationship between educational attainment and respiratory diseases using Mendelian randomization (MR). Datasets of educational attainment were obtained from the European Bioinformatics Institute and screened for genetic variants strongly associated with educational attainment according to the underlying assumptions of MR. Subsequently, the effect of these genetic variants on the risk of respiratory diseases was assessed using the inverse variance weighted method as the primary method of MR analysis, with MR-Egger, weighted median, weighted mode, and simple mode as secondary methods. Finally, MR-Egger intercept analysis, Cochran’s Q test and sensitivity analysis were used to assess the horizontal pleiotropy, heterogeneity, and robustness of the results of the MR analyses, respectively. MR analysis provided genetic evidence consistent with a modest protective effect of higher educational attainment on the risks of bronchitis (odds ratio [OR] 0.962, 95% confidence interval [CI] 0.949–0.975, P  < .001), pneumonia (OR 0.966, 95% CI 0.953–0.979, P  < .001), chronic obstructive pulmonary disease (OR 0.896, 95% CI 0.873–0.919, P  < .001), non-small cell lung cancer (OR 0.909, 95% CI 0.871–0.948, P  < .001), and pulmonary embolism (OR 0.950, 95% CI 0.922–0.980, P  < .001). MR-Egger intercept analyses provided no evidence of horizontal pleiotropy, and sensitivity analyses indicated that the results were robust. Higher educational attainment may have a protective effect against bronchitis, pneumonia, chronic obstructive pulmonary disease, non-small cell lung cancer, and pulmonary embolism, with genetic evidence consistent with a modest reduction in disease risk.