ABSTRACT
BACKGROUND: Identifying strategies for stopping nucleos(t)ide analogues (NUC) in patients with chronic hepatitis B (CHB) is a major goal in CHB management. Our study describes our tertiary-centre experience stopping nucleos(t)ide analogues (NUC) in CHB. METHODS: We conducted a retrospective cohort study of all individuals with CHB seen at the Calgary Liver Unit between January 2009 and May 2020 who stopped NUC. We collected baseline demographics and HBV lab parameters before and after stopping NUC with results stratified by off-treatment durability. Clinical flare was defined as alanine aminotransferase (ALT) over twice the upper limit of normal and virological flare as HBV DNA >2000 IU/mL. RESULTS: Forty-seven (3.5%) of the 1337 individuals with CHB stopped NUC therapy. During follow-up, six patients (12.8%) restarted NUCs because of a flare. All flares occurred within six months of discontinuation. Median time to restart treatment was 90 days (Q1 65, Q3 133). Upon restarting, all showed suppression of HBV DNA and ALT normalization. Factors associated with restarting NUC therapy included hepatitis B e antigen (HBeAg) positive status at first appointment and longer NUC consolidation therapy. Age, sex, ethnicity, liver stiffness measurement, choice of NUC, and quantitative hepatitis B surface antigen (qHBsAg) level at stopping were not associated with sustained response off-treatment. Six patients had functional cure with HBsAg loss. CONCLUSIONS: Stopping long-term NUC is feasible in HBeAg negative CHB. Hepatic flares can occur despite low levels of qHBsAg. Finite NUC therapy can be considered in eligible patients who are adherent to close monitoring and follow-up, particularly in the first six months after stopping NUC therapy.
ABSTRACT
BACKGROUND: Despite universal vaccination, chronic hepatitis B virus (HBV) infection remains a public health concern in North America owing to immigration. We aimed to characterize the number of people with a positive result of testing for HBV surface antigen (HBsAg) in Calgary, a large urban Canadian health care region, and to assess whether recommended laboratory tests and specialist consultation were done for those identified as HBsAg-positive. METHODS: Based on laboratory and Alberta Health Services administrative data, we identified all adults (age > 18 yr) with a positive HBsAg test result from Jan. 1 to Dec. 31, 2014 within the Calgary Zone. Demographic and relevant laboratory data were extracted within 6 months of a positive HBsAg test result, and referral to hepatology (2011-2014) was identified from data on referral to a centralized clinic. Parametric and nonparametric statistical methods were used for analyses. RESULTS: We identified 1214 HBsAg-positive people (584 women [48.1%]; median age 44 [interquartile range (IQR) 36-55] yr). A total of 1192 people (98.2%) had alanine aminotransferase testing (median level 23 [IQR 16-34] U/L; 117 [9.8%] with elevated levels), 682 (56.2%) had testing for HBV DNA (median level 2.8 [IQR 2.1-3.8] logIU/mL), 630 (51.9%) had HBV e antigen testing (negative result in 548 [87.0%]), and 145 (11.9%) had HBV e antibody testing (positive result in 111 [76.6%]). Overall, 144 people (11.9%) received anti-HBV treatment, and 390 (32.1%) were referred to a hepatologist. INTERPRETATION: Many HBsAg-positive people in Calgary did not receive the recommended laboratory assessments. The results highlight the necessity of continual public health efforts to screen for chronic HBV infection in Canada and to ensure adequate follow-up in order to reach the World Health Organization's goal of viral hepatitis elimination by 2030.
