Correlation Between Gut Microbiota And Bleeding After Anticoagulation In Patients With Nonvalvular Atrial Fibrillation

Objective:This experiment intends to analyze the changes of Gut Microbiota and the differences of clinical phenotypes after anticoagulation in patients with NVAF(nonvalvular atrial fibrillation)by16 S r RNA,so as to provide a more valuable biomarker for clinicians to guide patients with nonvalvular atrial fibrillation to reduce or predict the occurrence of bleeding events during the use of anticoagulants.Methods:Patients with nonvalvular atrial fibrillation who met the inclusion and exclusion criteria in the Department of Cardiovascular Medicine of the First Affiliated Hospital of Gannan Medical University between March 1,2021 and November 1,2022 were selected as the research objects,and divided into Bleeding AF group(N=27)and bleeding AF group(N=47).Clinical data,drug use and fecal samples were collected.Fecal samples were sequenced by16S r RNA with high throughput,QIIME2 was used for microbiome bioinformatics analysis,and Mann-Whitney U test or Kruskal-Wallis test was used to detect species differences.Linear discriminant analysis effect size(LEf Se)was used for quantitative analysis of biomarkers,and PICRUSt2 was used for functional analysis.Results:1.Comparison of clinical data:(1)There were significant differences in HAS-BLED Bleeding risk score and Total Cholesterol between AF group and Bleeding AF group(P<0.05).(2)ROC curve was used to calculate the area under the curve to analyze the diagnostic value of TC,HAS-BLED score and LOGREGR＿Pred1 for anticoagulation bleeding after AF.Compared with single index,the combined index of TC and HAS-BLED score was better.(3)No significant difference was found among the Warfarin,Rivaroxaban and Dabigatran groups(P<0.05).(4)There were statistically significant differences in the effects of different doses of rivaroxaban on bleeding after anticoagulation in AF patients(P<0.05),there was no statistical difference between the 15 Mg-group and the 20 Mg-group(P<0.017),there were statistical differences between the 10mg-group and the 15mg-group and the 20mg-group(P<0.017).2.Comparison of gut microbiota:(1)16S r RNA was used to analyze the difference of intestinal flora between AF group and Bleeding AF group.The abundance of intestinal flora in Bleeding AF group was lower than that in AF group,and the composition and structure of intestinal flora were different(P<0.05).(2)The analysis of differential flora at the genus level showed that Ligilactobacillus was the dominant differential flora in AF group,and the abundance was significantly higher than that in Bleeding AF group.Blautia was the dominant flora in Bleeding AF group,and the abundance was significantly higher than that in AF group.(3)LEf Se(LDAEffect Size)analysis indicated Bleeding AF the dominant microbiota in group were blautia,actinomyces,tyzzerella and atopobium.The dominant microbiota in AF groupwereCandidatus＿Arthromitus,Helicobacter,Limosilactobacillus,Candidatus＿arthromitus,Helicobacter,Limosilactobacillus,Candidatus＿arthromitus.(4)Envfit test was used to analyze the significance of TC and HAS-BLED score on gut microbiota:,and the results showed that TC(r~2=0.21,P value<0.01),HAS-BLED score(r~2=0.15,P value<0.01),TC and HAS-BLED score had a certain significant impact on gut microbiota.Monte Carlo Permutation Test was used to evaluate the correlation between TC and HAS-BLED scores on gut microbiota:,and the results showed that F=2.147,P<0.05,TC and HAS-BLED scores were correlated with gut microbiota:.TC was positively correlated with Actinomyces and Helicobacter.The HAS-BLED score was positively correlated with Actinomyces,Helicobacter and Lachnospiraceae＿NK4A136＿group.(5)Functional analysis:KEGG level2 annotation results showed that 2 pathways were enriched in AF group and Bleeding AF group,and KEGG level3 annotation results showed that 14 metabolic pathways were enriched in AF group and Bleeding AF group.Conclusion:For the first time,we provide potential evidence for the relationship between gut microbiota and post-anticoagulation bleeding in AF patients and its impact on clinical indicators.The differences in the abundance and composition of gut microbiota may affect the occurrence of bleeding events in patients with atrial fibrillation after anticoagulation.Exogenous supplementation of probiotics such as Faecalibacterium prausnitzii,Bifidobacterium,and Akkermansia mucophila may reduce the risk of bleeding after anticoagulation.By moderately reducing the total cholesterol level of patients with anticoagulant atrial fibrillation,correcting some reversible factors in the bleeding score such as lowering the patient’s blood pressure,improving the patient’s liver and kidney function,abstaining from alcohol,and correcting abnormal and INR values may effectively reduce the growth of opportunistic pathogens and further reduce the risk of bleeding in patients.