Study On Correlation Between Coagulation Function And Bleeding Events In Patients With Nonvalvular Atrial Fibrillation Treated With Dabigatran

Objective:The aim of this study is to find out the correlation between coagulation function and bleeding events in patients with nonvalvular atrial fibrillation treated with dabigatran.Methods:In this observational study,among the atrial fibrillation patients;80non-valvular atrial fibrillation patients under dabigatran medication fulfilling the inclusion criteria were enrolled.Patients with a diagnosis of atrial fibrillation admitted in cardiovascular medicine department of the First Affiliated Hospital of Guang Xi Medical university,Nanning from September 2018 to December 2020have been included.Clinical features and demographic data were obtained from the hospital in-patient and out-patient medical records,and the baseline characteristics of the bleeding and no bleeding group were compared.Results:A total of 80 NVAF patients（51 men,65±11）were enrolled in this study and the bleeding events occurred in 8 patients.Among them 56 were using DE110 and 24 were using DE150.While comparing the coagulation index before and after medication,bleeding group showed slight prolongation of APTT（p value0.03）and TT（p value 0.05）.Similarly,no bleeding group also showed prolongation of APTT（p value<0.01）and TT（p value<0.01）.Again,each coagulation parameters of bleeding were compared with no bleeding group.Study showed coagulation index PT（p value 0.1）,INR（p value 0.36）,APTT（p value0.49）,TT（p value 0.41）and PTA（p value 0.55）were not statistically significant.In this study,Spearman correlation analysis couldn’t find association between the coagulation parameters among bleeding and no bleeding group.While comparing DE110 and DE150,patients who received DE110 were comparatively younger（56.5 years）than those who received DE110（69 years）.DE150 had a low HAS-BLEED and CHA₂DS₂-VASc score with better renal function.By spearman correlation analysis among the drug doses,age（p value<0.01）,HAS-BLEED score（p value 0.01）and CHA₂DS₂-VASc score（p value<0.01）were negatively correlated.Similarly,body weight（p value<0.01）,Ccr and e GFR（0.02）are positively correlated with the dose of dabigatran（P<0.05）.Conclusions:Mild APTT prolongation and significant TT prolongation are changes in coagulation function caused by dabigatran etexillate,which does not increase the risk of bleeding.Since conventional coagulation parameters cannot accurately represent the bleeding risk of dabigatran,monitoring the bleeding risk of dabigatran is not recommended.Mild APTT prolongation and severe TT prolongation are not reasons to stop taking dabigatran.Individualized dabigatran dose selection based on the patient’s age,weight,renal function,and stratification of bleeding scores can help to reduce the occurrence of bleeding events.