Causal Relationship Between Chronic Obstructive Pulmonary Disease and Respiratory Tuberculosis Susceptibility: A Two-Sample Bayesian Weighted Mendelian Randomization Study.

The causal relationship between chronic obstructive pulmonary disease (COPD) and respiratory tuberculosis (TB) remains unclear due to limited evidence from prospective studies. Therefore, this study aimed to assess the causal relationship between COPD and respiratory TB using a two-sample Bayesian weighted Mendelian randomization (BWMR) study. The genetic instrumental variants (IVs) for COPD and respiratory TB were obtained from the IEU Open GWAS project in 2021. The inverse variance weighted (IVW) method was used as the main statistical analysis method, and the results supplemented with weighted median and BWMR methods. Pleiotropy was tested using the MR-PRESSO global test and MR-Egger regression. Heterogeneity was analyzed using Cochran's Q statistics. The robustness of the results was tested using the leave-one-out sensitivity analysis method. In our two-sample BWMR analysis, we found that patients with COPD had a higher risk of respiratory TB based on IVW (OR = 1.259, 95% CI: 1.011-1.568; p = 0.040), weighted median (OR = 1.287, 95% CI: 0.981-1.688; p = 0 0.069), and BWMR (OR = 1.240, 95% CI: 1.013-1.518; p = 0.037). Reverse BWMR analysis showed that respiratory TB has no causal effect on COPD. We found no significant pleiotropy or heterogeneity in all selected IVs. The results were stable when removing the SNPs individually. This two-sample BWMR study provided strong evidence that individuals with COPD are at a higher risk of respiratory TB at the genetic level, while respiratory TB has no causal effect on COPD.