[Development of Markov models for economics evaluation of strategies on hepatitis B vaccination and population-based antiviral treatment in China].

Objective: To construct the Markov models to reflect the reality of prevention and treatment interventions against hepatitis B virus (HBV) infection, simulate the natural history of HBV infection in different age groups and provide evidence for the economics evaluations of hepatitis B vaccination and population-based antiviral treatment in China. Methods: According to the theory and techniques of Markov chain, the Markov models of Chinese HBV epidemic were developed based on the national data and related literature both at home and abroad, including the settings of Markov model states, allowable transitions and initial and transition probabilities. The model construction, operation and verification were conducted by using software TreeAge Pro 2015. Results: Several types of Markov models were constructed to describe the disease progression of HBV infection in neonatal period, perinatal period or adulthood, the progression of chronic hepatitis B after antiviral therapy, hepatitis B prevention and control in adults, chronic hepatitis B antiviral treatment and the natural progression of chronic hepatitis B in general population. The model for the newborn was fundamental which included ten states, i.e. susceptiblity to HBV, HBsAg clearance, immune tolerance, immune clearance, low replication, HBeAg negative CHB, compensated cirrhosis, decompensated cirrhosis, hepatocellular carcinoma (HCC) and death. The susceptible state to HBV was excluded in the perinatal period model, and the immune tolerance state was excluded in the adulthood model. The model for general population only included two states, survive and death. Among the 5 types of models, there were 9 initial states assigned with initial probabilities, and 27 states for transition probabilities. The results of model verifications showed that the probability curves were basically consistent with the situation of HBV epidemic in China. Conclusion: The Markov models developed can be used in economics evaluation of hepatitis B vaccination and treatment for the elimination of HBV infection in China though the structures and parameters in the model have uncertainty with dynamic natures.

[Cost-effectiveness and affordability of strategy for preventing mother-to-child transmission of hepatitis B in China].

Objective: To evaluate the cost effectiveness of nationwide prevention of mother to child transmission (PMTCT) strategy for hepatitis B, and estimate the willing to pay and budget impacts on the PMTCT. Methods: The decision analytic Markov model for the PMTCT was constructed and a birth cohort of Chinese infants born in 2013 was used to calculate the cost-effectiveness of the PMTCT among them compared with those receiving no intervention. The parameters in the model were obtained from literatures of national surveys or Meta-analysis. The costs, cases of HBV-related diseases and quality-adjusted life-years (QALYs) were obtained from the societal and payer perspectives, respectively. The incremental cost-effectiveness ratio (ICER) was used as measures of strategy optimization. One-way and probability sensitivity analysis were performed to explore the uncertainty of the primary results. In addition, cost-effectiveness acceptability curve and cost-effectiveness affordability curves were drawn to illustrate the cost effectiveness threshold and financial budget of the PMTCT strategy. Results: The lifetime cost for PMTCT strategy was 4 063.5 yuan (RMB) per carrier, which was 37 829.7 yuan (RMB) lower compared with those receiving no intervention. Due to the strategy, a total of 24.516 1 QALYs per person would be gained, which was higher than that in those receiving no intervention. From societal perspective, the ICER was -59 136.6 yuan (RMB) per additional QALYs gained, indicating that the PMTCT is cost effective. The results were reliable indicated by one-way, multi-way and probability sensitivity analyses. By the CEAC, the willing to pay was much lower than the cost-effectiveness threshold. From the affordability curve of the PMTCT strategy, the annual budget ranged from 590.4 million yuan (RMB) to 688.8 million yuan (RMB), which was lower than the financial ability. Based on the results of cost-effectiveness affordability curves, the higher annual budget was determined, the higher probability of affordability for the PMTCT would be obtained under the same willing to pay state. Only when the annual budget reaches 688.8 million yuan (RMB), the goal of PMTCT would be fully realized. Conclusions: The PMTCT strategy in China was cost effective, and the cost is not beyond the financial budget needed and the willing to pay. The strategy, which is consistent with the global hepatitis B elimination efforts, should be conducted widely in China.

[Cost-effectiveness of community-based treatment of chronic hepatitis B in China].

Objective: Since eliminating hepatitis B in China would need considerable public health resources, the economics problem of the strategy of community-based antiviral treatment for chronic hepatitis B (CHB) has become an important issue. The cost-effectiveness and affordability of the strategy were evaluated in this study. Methods: According to the advocacy on eliminating hepatitis B by WHO and the comprehensive protocol of community based prevention of major infectious diseases and the guideline for CHB prevention and treatment in China, the decision analytic Markov model was constructed with the parameters from national surveys or Meta-analysis. A cohort population aged 20-59 years was used as study subjects. The strategy of CHB antiviral treatment was compared with the strategies of hepatitis B vaccination and non-intervention, respectively. The costs and disability-adjusted life years (QALYs) of the strategies were calculated from the societal and payer perspectives. The incremental cost-effectiveness ratio (ICER) and the cost-effectiveness ratio (CER) were calculated for the comparison of the strategies. One-way and probability sensitivity analysis were performed for uncertainty of the results. And the cost-effectiveness and affordability curves were introduced to estimate the budget impact on the strategies. Results: In the Chinese aged 20-59 years, the ICER of CHB antiviral treatment was 37 598.6 yuan (RMB) per QALYs and the ICERs were smaller in the low age groups, indicating that the antiviral treatment strategy is cost-effective and low age groups should be the priority population. The ICER of hepatitis B vaccination was -64 000.0 yuan (RMB) per QALYs, indicating that hepatitis B vaccination is cost saving. The CER of CHB antiviral treatment ranged from 731.8 to 1 813.3 yuan (RMB) per QALYs compared with hepatitis B vaccination, and the CER of CHB antiviral treatment was higher than that of hepatitis B vaccination in all age groups, indicating that hepatitis B vaccination would be more cost-effective than CHB antiviral treatment. The price of antiviral drug, entercavir, can influence the cost effectiveness of CHB antiviral treatment. If the price of entercavir declined half, CHB antiviral treatment would be cost-saving. The probability sensitivity analysis showed that people's willing to pay for CHB antiviral treatment should not be ignored, although the results of economics evaluation of CHB antiviral treatment were reliable. The results of affordability analysis indicated that the antiviral treatment strategy could not be implemented with the budget lower than 30 million yuan (RMB), the probability of implementing the strategy was 42.6% if the budget reaches 127 million yuan (RMB), and only when the budget reaches 269 million yuan (RMB), the goal of CHB antiviral treatment strategy can be fully realized. Conclusions: Although the strategy of CHB antiviral treatment as prevention in Chinese aged 20-59 years is cost-effective, it is not an appropriate public health measure due to the high cost. The cost effectiveness would be higher by conducting hepatitis B vaccination and then antiviral treatment in susceptible population.

[Survey of economic burden of hepatitis B-related diseases in 12 areas in China].

Objective: Less surveys on the economic burden of hepatitis B (HB)-related diseases have been conducted in China, so the socioeconomic harm caused by the diseases is not clear and the key parameters for economic evaluation of hepatitis B prevention and treatment are lacking. This study aimed to analyze the direct, indirect and intangible expenditures of hospitalized patients with HB-related diseases during hospitalization and during a year in different areas of China. Methods: The hospitals for infectious diseases and the large general hospitals in 12 areas in China were selected in the study. All the inpatients with HB-related diseases were surveyed by cluster sampling of consecutive cases. The direct expenditure included direct medical cost and direct non-medical cost. The indirect expenditure, including work loss of patients and caregivers, were calculated by using human capital method for urban and rural populations in 12 areas. The intangible expenditure were reflected by willing to pay and stochastic tournament. The influencing factors of direct and indirect costs were identified by stepwise linear multi-variation regression analysis. Results: A total of 27 hospitals in 12 areas were included in the survey. A total of 4 718 cases were surveyed, the overall response rate was 77.7%. The average hospital stay was 29.2 days (27-34) and the hospitalization expenditure was averagely 16 832.80 yuan (RMB) per case, in which the highest proportion (61.2%) was medicine fees [10 365.10 yuan (RMB)]. The average direct expenditure and indirect expenditure were consistent with the severity of illness, which were 18 336.10 yuan (RMB) and 4 759.60 yuan (RMB) respectively, with the ratio of 3.85 ∶ 1. The direct medical expenditure [17 434.70 yuan (RMB)] were substantially higher than the direct non-medical expenditure [901.40 yuan (RMB)]. It was found that the hospitalization expenses was highest in direct medical expenditure and the transportation expenses was highest in direct non-medical expenditures. Among the average indirect expenditure, the loss of income for the patients [3 832.50 yuan (RMB)] was higher than that for the caregivers [927.20 yuan (RMB)]. The total direct and indirect expenditure was highest for liver transplantation, followed by severe hepatitis, hepatocellular carcinoma and decompensated cirrhosis, acute hepatitis B, compensated cirrhosis and chronic hepatitis B. The influencing factors for both direct and indirect expenditure were high hospital level, severity of hepatitis B, living in urban area, antiviral therapy, long hospitalization and monthly income of family. For average 3.74 outpatient visits and 1.51 hospitalization, the average annual direct, indirect and intangible expenditure for HB-related diseases were 30 135.30, 6 253.80 and 44 729.90 yuan (RMB) [totally 81 119.00 yuan (RMB)], accounting for 37.3%, 7.7% and 55.0%, respectively. Of the annual direct medical expenditure [28 402.80 yuan (RMB)], which were much higher than non-medical expenditure [1 732.50 yuan (RMB)], hospitalization expenditure [26 074.20 yuan (RMB)] was higher than outpatient visit expenditure [4 061.10 yuan (RMB)]. The annual indirect expenditures for outpatient visit and hospitalization were 763.60 and 5 490.10 yuan (RMB), respectively. Of the annual intangible expenditure, the highest was that for primary hepatocellular carcinoma, followed by cirrhosis, chronic hepatitis B, severe hepatitis B, liver transplantation and acute hepatitis B. Conclusions: A heavy economic burden has been caused by HB-related diseases in China, and patients are more likely to rely on medical service rather than non-medical service. It is necessary to take effective treatment measures to prevent the adverse outcome of HB related diseases and achieve significant economic benefits. The influence of HB related diseases on mental health of the people can be reflected by an economics term, intangible expenditure.