The Association Of Impulsivity And Fecal Microbiota In Individuals Who Ceased Methamphetamine

Objective: Methamphetamine(MA)is a highly addictive psychoactive substance.Impulsivity is involved in the formation of addictive behavior,and fecal microbiota has been suggested to alter after MA usage.Therefore,identifying the association between impulsivity and fecal microbiota in MA addicts may provide a theoretical basis to understand impulsivity in MA addicts.It was found that MA could not only alter the structure of the fecal microbiota as well as the expression of genes and metabolic pathways in the host’s brain and small intestine but also influence the formation of substance dependence and the impulsivity levels of the host.Therefore,we hypothesized that 1.MA addicts were with higher impulsivity;2.fecal microbiota altered in MA addicts;3.fecal microbiota was associated with impulsivity in MA addicts.We investigated the impulsivity and the characteristics of fecal microbiota in abstinent MA addicts and healthy controls(HC),to identify the impulsivity level and specific fecal microbiota abnormalities in the MA addicts.Besides,we further explored the associations between the characteristics of fecal microbiota and impulsivity in the MA addicts,so as to provide a theoretical basis for understanding impulsivity in the MA addicts.Methods: A total of 112 subjects were included in the study,including 62 MA addicts in abstinention and 50 HC.The Barratt Impulsiveness Scale(BIS)was used to assess impulsivity levels.Stool samples were collected for 16 S r RNA sequencing analysis.The corresponding statistical methods(two independent samples t-test and Mann-Whitney test)were selected according to the type of data to compare the demographic features and impulsivity levels.We also investigated the diversity,abundance,and components of fecal microbiota.Spearman correlation analysis was used to explore the correlation between impulsivity levels and fecal microbiota at the genus level.Results: 1.MA addicts were with higher scores in BIS_total,BIS_motor,BIS_attentional,and BIS_no plan than the HC group;2.Abnormal structural and compositional fecal microbiota was observed in the MA addicts,and the relative abundance of probiotics such as Bacteroides,Parasutterella,and Bifidobacterium of the MA addicts was eliminated compared with the HC group,while there was an increase in the relative abundance of opportunistic pathogens such as Lachnoclostridium,Escherichia-Shigella,and Enterobacter;3.The scores of BIS_motor in the MA group were negatively correlated with the relative abundance of Enterobacter(r =-0.381,P = 0.002).Conclusion: 1.MA addicts were with higher impulsivity levels than HC group even after abstention of MA;2.MA addicts exhibited a dysbiosis characterized by decrease of probiotics and increase of opportunistic pathogens;3.Impulsivity level was negatively correlated with the abundance of Enterobacter in MA addicts.Therefore,the current study observed a higher impulsivity level and characteristic abnormalities in fecal microbiota in MA addicts even during MA abstinence,as well as the potential involvement of Enterobacter as the pathophysiological mechanism of impulsivity in MA addicts.