摘要Hepatitis B virus(HBV)represents the commonest etiologic agent of acute-on-chronic liver failure(ACLF)in most Asian countries.Nucleos(t)ide analogs(NAs)are effective in the treatment of chronic HBV infections,but may also exacerbate the disease and stimulate its development into HBV-associated ACLFif not used appropriately.The current study aimed to assess the prevalence and severity of HBV-associated ACLF as a result from irregular medication of NAs(IMNA).A total of 1134individuals with HBV-associated ACLF in nine hospitals in Heilongjiang Province were enrolled in this study between 2005 and 2015.Among these,777 chronic hepatitis B(CHB)and 357 HBV-associated liver cirrhosis cases were classified based on various predisposing factors,including IMNA,HBV reactivation(HBVR),infections,treatment drugs,alcohol use and others(hepatitis C virus,hepatitis E virus,gastrointestinal bleeding and unknown reasons).The percentage and improvement rate were examined.Among individuals with HBV-associated ACLF and CHB,IMNAwas found in 9.01％,HBVR in 46.20％,infections in 9.52％,treatment drugs in 14.67％,alcohol in 11.71％,and others in 24.58％as predisposing factors.Improvement rates in cases with IMNA,HBVR,infections,treatment drugs,alcohol and others were 41.43％,58.50％,58.11％,56.14％,53.85％,and 65.97％,respectively.Multivariable analysis showed that IMNA,others,infections,hepatic encephalopathy and hepatorenal syndrome were associated with prognosis.OnlyIMNAindependently predicted HBV-associated ACLF prognosis.Overall,our study demonstrated that the percentage of IMNA-induced HBV-associated ACLF was 12.61％,and worse disease conditions resulted from IMNA compared with other factors.Thus,the suitability of treatment with Nas should be thoroughly evaluated.