Background: Constipation may be related to an imbalance in flora imbalance. In this study, univariate and multivariate Mendelian randomization (MR) studies were used to further understand the causal relationship between different members of genus Eubacteriumand constipation.
Methods: The constipation and genus Eubacterium datasets were obtained from the Integrative Epidemiology Unit (IEU) Open Genome-Wide Association Study (GWAS) database. The causal effects between constipation and genus Eubacterium were analyzed using MR-Egger, Weighted median, Simple mode, Weighted mode and Inverse variance weighted (IVW). In univariate MR analysis (UVMR), genus Eubacillus was the exposure factor, constipation was the outcome. In addition, the reliability of UVMR analysis was assessed by sensitivity analyses (heterogeneity tests, horizontal pleiotropy tests and leave-one-out (LOO) analysis). Finally, the MVMR analysis was performed.
Results: In the UVMR analysis, genus Eubacterium rectale group id.14374 (p=0.043, OR=0.805) and genus Eubacterium brachy group id.11296 (p=0.036, OR=0.904) were all protective factors on constipation. The results of sensitivity analysis showed that UVMR analysis was reliable. In the MVMR analysis, genus Eubacterium rectalegroup was still a significant protective factor (p=0.007, OR=0.80), while genus Eubacterium brachy group was not a significant protective factor for constipation (p=0.151, OR=0.94) .
Conclusion: The results of study supported that genus Eubacterium rectale group had a significant causal relationship with constipation, and the increase of genus Eubacterium rectale group could reduce the risk of constipation.