Causal association between type 2 diabetes and risk of pulmonary tuberculosis: A Mendelian randomization study

Abstract

Abstract Objective: This study examined whether T2D is causally associated with the risk of PTB. Methods: Genome-wide association studies (GWASs) of type 2 diabetes (T2D) and pulmonary tuberculosis (PTB) were performed using a Mendelian randomization (MR)-based platform. We used publicly available summary statistics datasets from GWAS meta-analyses of T2D in individuals of East Asian descent (n = 191764) as the exposure and a GWAS dataset for PTB included in Biobank Japan (n = 212453) as the outcome. Two-sample Mendelian randomization (MR) analysis using the inverse variance-weighted (IVW), weighted median, and MR-Egger regression methods was performed to examine the causal relationship between T2D and PTB risk. Results: We selected 81 single-nucleotide polymorphisms (SNPs) with genome‐wide significance from GWASs on T2D as the instrumental variables. Consistent associations between T2D and PTB were observed with all three methods, which suggests that T2D is positively associated with an increased risk of PTB. Moreover, the findings showed no evidence that the observed causal effect between T2D and the risk of PTB was affected by genetic pleiotropy (MR-Egger intercept = -0.024, P = 0.188). Conclusion: MR analysis provided strong evidence indicating that T2D may be causally associated with an increased risk of PTB.