Cost-effectiveness of population screening for Helicobacter pylori in preventing gastric cancer and peptic ulcer disease, using simulation

Management of Helicobacter pylori infection-the Maastricht V/Florence Consensus Report

Important progress has been made in the management of Helicobacter pylori infection and in this fifth edition of the Maastricht Consensus Report, key aspects related to the clinical role of H. pylori were re-evaluated in 2015. In the Maastricht V/Florence Consensus Conference, 43 experts from 24 countries examined new data related to H. pylori in five subdivided workshops: (1) Indications/Associations, (2) Diagnosis, (3) Treatment, (4) Prevention/Public Health, (5) H. pylori and the Gastric Microbiota. The results of the individual workshops were presented to a final consensus voting that included all participants. Recommendations are provided on the basis of the best available evidence and relevance to the management of H. pylori infection in the various clinical scenarios.

Mass Eradication of Helicobacter pylorito Prevent Gastric Cancer: Theoretical and Practical Considerations

Although the age-adjusted incidence of gastric cancer is declining, the absolute number of new cases of gastric cancer is increasing due to population growth and aging. An effective strategy is needed to prevent this deadly cancer. Among the available strategies, screen-and-treat for Helicobacter pylori infection appears to be the best approach to decrease cancer risk; however, implementation of this strategy on the population level requires a systematic approach. The program also must be integrated into national healthcare priorities to allow the limited resources to be most effectively allocated. Implementation will require adoption of an appropriate screening strategy, an efficient delivery system with a timely referral for a positive test, and standardized treatment regimens based on clinical efficacy, side effects, simplicity, duration, and cost. Within the population, there are subpopulations that vary in risk such that a "one size fits all" approach is unlikely to be ideal. Sensitivity analyses will be required to identify whether the programs can be utilized by heterogeneous populations and will likely require adjustments to accommodate the needs of subpopulations.

Helicobacter pylori test-and-treat program can be cost-effective to prevent gastric cancer in Taiwanese adults: referred to the nationwide reimbursement database

BACKGROUND

Helicobacter pylori infection increases the risk of gastric cancer. The study aimed to compare cost-effectiveness ratios of H. pylori test-and-treat programs to prevent gastric cancer in Taiwan, referring to the nationwide reimbursement database and expected years of life lost.

MATERIALS AND METHODS

During 1998-2009, there were 12,857 females and 24,945 males with gastric adenocarcinoma in Taiwan National Cancer Registry. They were followed up to 2010 and linked to the reimbursement database of National Health Insurance and the national mortality registry to determine lifetime health expenditures and expected years of life lost. Cost-effectiveness ratios of H. pylori test-and-treat programs for prevention of gastric adenocarcinoma were compared between screenings with (13) C-urea breath test and with anti-H. pylori IgG.

RESULTS

The test-and-treat program with anti-H. pylori IgG to prevent gastric adenocarcinoma had lower incremental cost-effectiveness ratios than that with (13) C-urea breath test in both sexes (females: 244 vs 1071 US dollars/life-year; males: 312 vs 1431 US dollars/life-year). Cost saving would be achieved in an endemic area where H. pylori prevalence was >73.5%, or by selecting subpopulations with high absolute risk reduction rates of cancer after eradication. Moreover, expected years of life lost of gastric adenocarcinoma were higher and the incremental cost-effectiveness ratios of test-and-treat programs were more cost-effective in young adults (30-69 y/o) than in elders (≥70 y/o).

CONCLUSIONS

The test-and-treat program with anti-H. pylori IgG shall be cost-effective to prevent gastric adenocarcinoma in a high endemic area, especially beginning at 30 years of age when H. pylori prevalence rates become stabilized.

A patient-level calibration framework for evaluating surveillance strategies: a case study of mammographic follow-up after early breast cancer

OBJECTIVE

Currently all women who have completed their primary treatment for early breast cancer are invited to receive routine annual mammography. There is no randomized controlled trial evidence to support this schedule, and model-based analysis is required. This paper describes a novel data collection and model calibration process to analyze the cost-effectiveness of alternative follow-up schedules for early breast cancer survivors.

METHODS

A discrete event simulation model describes the progression of early breast cancer after the completion of primary treatment, representing impalpable and palpable recurrence and the detection of impalpable disease via follow-up mammography. Retrospective data from the South Australian Cancer Registry and clinical and administrative hospital databases were linked for 407 postmenopausal women diagnosed with moderate-prognosis early breast cancer from 2000 to 2008. These data formed the basis of a patient-level probabilistic calibration process.

RESULTS

For 50- to 69-year-old survivors, annual follow-up for 5 years, with visits every 2 years thereafter, appears to be cost-effective. For women aged 70 to 79 years at diagnosis, a surveillance schedule similar to general population screening (2 yearly) appears to be most cost-effective if high rates of adherence can be maintained.

CONCLUSIONS

This study demonstrated the potential value of combining linked, retrospective data and decision analytic modeling to provide estimates of costs and health outcomes that are sufficiently robust to inform cancer clinical guidelines and individual patient decisions regarding appropriate follow-up schedules.

Review article: the epidemiology and prevention of gastric cancer

BACKGROUND

Gastric cancer can be divided into cardia and noncardia gastric adenocarcinoma (NCGA). Non cardia gastric cancer is a disease that has declined in global incidence but has remained as an extremely lethal cancer.

AIM

To review recent advances in epidemiology and strategies in prevention of non cardia gastric cancer.

METHODS

A rapid literature search strategy was developed for all English language literature published before March 2013. The search was conducted using the electronic databases PubMed and EMBASE. The search strategy included the keywords 'stomach neoplasms', 'gastric cancer', 'epidemiology', 'risk factor', 'early detection of cancer', 'mass screening', 'cancer burden', 'prevention' and 'cost-effectiveness'. The search strategy was adjusted according to different requirements for each database. The specific search was also performed in cancer-related websites for country-specific information. The search was limited to past 10 years.

RESULTS

Gastric cancer is the fifth most common cancer but the third leading cause of cancer death. The case fatality rate is 75%. Screening by radiological or endoscopic methods has limited success in prevention of gastric cancer. Helicobacter pylori has been identified as a carcinogen, accounting for 60-70% of gastric cancer globally and eradication is a potential preventive measure. A meta-analysis in 2009 demonstrated that individuals treated with H. pylori eradication therapy can reduce gastric cancer risk. The extended Shandong Intervention trial that lasted 14.3 years showed that H. pylori eradication therapy significantly reduced gastric cancer incidence by 39%. Consensus groups from Asia, Europe and Japan have recommended H. pylori eradication as primary prevention in high-risk areas. Following eradication therapy, endoscopic surveillance of pre-malignant lesions using enhanced imaging appears to be another promising preventive strategy.

CONCLUSIONS

Gastric cancer remains a major diagnostic and therapeutic challenge. There is emerging evidence that H. pylori eradication in high gastric cancer regions can lead to a decline in the incidence of this highly lethal disease.

When to use discrete event simulation (DES) for the economic evaluation of health technologies? A review and critique of the costs and benefits of DES

Modelling in economic evaluation is an unavoidable fact of life. Cohort-based state transition models are most common, though discrete event simulation (DES) is increasingly being used to implement more complex model structures. The benefits of DES relate to the greater flexibility around the implementation and population of complex models, which may provide more accurate or valid estimates of the incremental costs and benefits of alternative health technologies. The costs of DES relate to the time and expertise required to implement and review complex models, when perhaps a simpler model would suffice. The costs are not borne solely by the analyst, but also by reviewers. In particular, modelled economic evaluations are often submitted to support reimbursement decisions for new technologies, for which detailed model reviews are generally undertaken on behalf of the funding body. This paper reports the results from a review of published DES-based economic evaluations. Factors underlying the use of DES were defined, and the characteristics of applied models were considered, to inform options for assessing the potential benefits of DES in relation to each factor. Four broad factors underlying the use of DES were identified: baseline heterogeneity, continuous disease markers, time varying event rates, and the influence of prior events on subsequent event rates. If relevant, individual-level data are available, representation of the four factors is likely to improve model validity, and it is possible to assess the importance of their representation in individual cases. A thorough model performance evaluation is required to overcome the costs of DES from the users' perspective, but few of the reviewed DES models reported such a process. More generally, further direct, empirical comparisons of complex models with simpler models would better inform the benefits of DES to implement more complex models, and the circumstances in which such benefits are most likely.

Cost-effectiveness of screening and treating Helicobacter pylori for gastric cancer prevention

Gastric cancer is the second leading cause of cancer-related death worldwide. A meta-analysis of seven randomized controlled trials concluded that Helicobacter pylori eradication reduces gastric cancer incidence by 35%. Current consensus is that H. pylori screening and treatment is cost-effective only in high-risk populations. This paper provides an up-to-date overview of the evidence for cost-effectiveness of H. pylori screening and treatment in different population settings and risk levels for H. pylori infection. Ten unique cost-effectiveness or cost-utility analyses were identified. All found that screening for H. pylori to prevent gastric cancer in the general population costs less than $50,000 per LYG. This finding was robust for differences in H. pylori prevalence, gender and ethnicity. Based on limited evidence, re-treatment (for treatment failure), repeated screening, limiting screening and treatment to those with the CagA phenotype, or universal treatment, does not appear to be cost-effective. However, most included studies failed to consider both the broader benefits as well as the adverse effects of widespread use of antibiotics for H. pylori.

Screening for gastric cancer and surveillance of premalignant lesions: a systematic review of cost-effectiveness studies

BACKGROUND

Cost-effectiveness studies are highly dependent on the models, settings, and variables used and should be based on systematic reviews. We systematically reviewed cost-effectiveness studies that address screening for gastric cancer and/or surveillance of precancerous conditions and lesions.

MATERIALS AND METHODS

A systematic review of cost-effectiveness studies was performed by conducting a sensitive search in seven databases (PubMed, Scopus, Web of Science, Current Contents Connect, Centre for Reviews and Dissemination, Academic Search Complete, and CINAHL Plus), independently evaluated by two investigators. Articles were evaluated for type of study, perspective, model, intervention, incremental cost-effectiveness ratio, clinical or cost variables, and quality, according to published guidelines.

RESULTS

From 2395 abstracts, 23 articles were included: 19 concerning population screening and 4 on following up premalignant lesions. Studies on Helicobacter pylori screening concluded that serology was cost-effective, depending on cancer incidence and endoscopy cost (incremental cost-effectiveness ratio: 6264-25,881), and eradication after endoscopic resection was also cost-effective (dominant) based on one study. Studies on imaging screening concluded that endoscopy was more cost-effective than no screening (incremental cost-effectiveness ratio: 3376-26,836). Articles on follow-up of premalignant lesions reported conflicting results (incremental cost-effectiveness ratio: 1868-72,519 for intestinal metaplasia; 18,600-39,800 for dysplasia). Quality assessment revealed a unanimous lack of a detailed systematic review and fulfillment of a median number of 23 items (20-26) of 35 possible ones.

CONCLUSIONS

The available evidence shows that Helicobacter pylori serology or endoscopic population screening is cost-effective, while endoscopic surveillance of premalignant gastric lesions presents conflicting results. Better implementation of published guidelines and accomplishment of systematic detailed reviews are needed.

Helicobacter pylori infection in Europe: current perspectives

There is a commonly held perception that Helicobacter pylori related diseases are declining, however these are still associated with a high risk of morbidity and mortality. In recent years worrying themes have emerged such as increasing levels of antibiotic resistance and falling cure rates which illustrate there is no room for complacency with respect to H. pylori. In addition there are many significant issues which have not been elucidated regarding the role played by H. pylori in very serious pathologies such as gastric and esophageal cancer and other more benign disorders common in the developed world such as gastroesophageal reflux disease, functional dyspepsia and perhaps obesity which carry a significant impact both economically and as regards to symptoms. Future guidelines aimed at European practitioners and patients will need to address the questions raised by these issues as well as the more familiar areas such as constituents and duration of therapy.

Endoscopic methods

Endoscopic methods to recognise and treat early gastrointestinal malignancies have increased in recent years. This has resulted in more lesions being diagnosed at an early stage and a shift away from invasive surgery towards endoscopic resection. However, it is necessary for the endoscopist to understand the key principles behind advanced endoscopic diagnosis and the new therapeutic options available. This chapter will review the advances in endoscopic techniques and methods which are changing the way we diagnose and treat these cancers. It will examine the general principles behind advanced endoscopy and then examine their application in Barrett's neoplasia, gastric cancer and the dysplasia associated lesions or masses associated with ulcerative colitis. It will focus on the best techniques for each of the above pathology.

Effect of a community screening for Helicobacter pylori: a 5-Yr follow-up study

BACKGROUND

Helicobacter pylori (H. pylori) screening and eradication may reduce the incidence of gastric cancer, AND AIMS: peptic ulcer, and ulcer complications, and it may reduce symptoms in a small proportion of individuals with functional dyspepsia. This study aimed to assess the effect of community H. pylori screening and treatment on the prevalence of dyspepsia, and as secondary outcomes, the effect on dyspepsia-related health-care consumption and quality of life over 5 yr.

METHODS

In 1998-1999, individuals aged 40-65 yr were randomized to H. pylori screening and treatment or to the control group. Five years later, the participants were sent a questionnaire to assess the prevalence of dyspepsia and quality of life. In addition, we obtained information from registers on the use of endoscopies and prescription medication. An economic evaluation was done alongside the randomized trial.

RESULTS

Of 12,530 participants attending the study at baseline, 11,065 (88%) were traced and contacted at the 5-yr follow-up. The response rate was 94%. At baseline, 17.5% in the screened group were H. pylori-positive. The absolute reduction in dyspepsia during the first year was 4% in the screened group, whereas no change was observed in the unscreened group; this rate remained constant during the next 4 yr. Quality of life did not change. A small effect was found for dyspepsia-related consultations and sick leave days, but not on the prescription rate of ulcer drugs. A 33% lower ulcer incidence (107 ulcers vs 148 ulcers) was seen in the screened group compared to the unscreened group.

CONCLUSION

A population H. pylori screening and treatment program in an H. pylori low-prevalence area had only a modest, but insignificant, effect on the rate of dyspepsia, and a modest, significant effect on the consultation rate and sick leave days for dyspepsia, but resulted in a decreased ulcer incidence. The intervention resulted in an increased cost due to H. pylori screening and treatment.

Cost-effectiveness analysis of Helicobacter pylori screening in prevention of gastric cancer in Chinese

OBJECTIVES

The aim of this study was to evaluate the costs and effectiveness associated with no screening, Helicobacter pylori serology screening, and the 13C-urea breath test (UBT) for gastric cancer in the Chinese population.

METHODS

A Markov model simulation was carried out in Singaporean Chinese at 40 years of age (n = 478,500) from the perspective of public healthcare providers. The main outcome measures were costs, number of gastric cancer cases prevented, life-years saved, quality-adjusted life-years (QALYs) gained from the screening age to death, and incremental cost-effectiveness ratios (ICERs), which were compared among the three strategies. The uncertainty surrounding ICERs was addressed by scenario analyses and probabilistic sensitivity analysis using Monte Carlo simulation.

RESULTS

The ICER of serology screening versus no screening was $25,881 per QALY gained (95 percent confidence interval (95 percent CI), $5,700 to $120,000). The ICER of UBT versus no screening was $53,602 per QALY gained (95 percent CI, $16,000 to $230,000). ICER of UBT versus serology screening was $470,000 per QALY gained, for which almost all random samples of the ICERs distributed above $50,000 per QALY.

CONCLUSIONS

It cannot be confidently concluded that either H pylori screening was a cost-effective strategy compared with no screening in all Chinese at the age of 40 years. Nevertheless, serology screening has demonstrated much more potential to be a cost-effective strategy, especially in the population with higher gastric cancer prevalence.

The seroepidemiology of Helicobacter pylori infection in Australia

BACKGROUND

Infection with Helicobacter pylori is common worldwide and a significant cause of upper gastrointestinal disease. Prevalence of this infection varies in different population groups internationally. Because of the invasiveness of specimen collection for bacteriologic diagnosis and the expense of tests such as labeled urea breath tests, serology is the most feasible means of determining the population epidemiology of H. pylori. The aim of this study was to describe the seroepidemiology of H. pylori infection in Australia.

METHODS

H. pylori-specific ELISA for the presence of IgG antibodies was performed on a representative sample of 2413 sera from Australia in 2002, using validated serosurveillance methods.

RESULTS

The overall seroprevalence of H. pylori infection in Australia was 15.1% in 2002, with no statistical difference between genders. Seropositivity rates increased progressively with age, ranging between 4.0% in the 1-4-year-olds and 23.3% in the 50-59-year-olds.

CONCLUSIONS

The prevalence of infection with H. pylori in Australia was lower than rates reported in other developed countries, at 15.4%. This study provides important baseline measurements for future preventive measures including vaccine research and development. Further studies to determine subgroups at higher risk of infection may help target the more susceptible populations.

Treatment of Helicobacter pylori and prevention of gastric cancer

Gastric cancer is the second commonest fatal malignancy in the world with a high incidence in China. Helicobacter pylori infection is an important factor in the pathogenesis of gastric cancer. Epidemiological studies have shown a strong causal relationship between H. pylori infection and gastric cancer. Animal studies also show that eradication of H. pylori infection, especially at the early stage, is effective in preventing H. pylori-related gastric carcinogenesis. H. pylori eradication leads to regression and prevents the progression of gastric precancerous lesions, but only in a minority of cases. H. pylori eradication appears to be the most promising approach in gastric cancer prevention. The current available data in human studies showed that H. pylori eradication can reduce the risk of developing gastric cancer and this strategy is more useful in patients without atrophic gastritis or intestinal metaplasia. A longer follow-up and additional studies are needed for better understanding this issue.

Quantitative assessment model for gastric cancer screening

AIM: To set up a mathematic model for gastric cancer screening and to evaluate its function in mass screening for gastric cancer.

METHODS: A case control study was carried on in 66 patients and 198 normal people, then the risk and protective factors of gastric cancer were determined, including heavy manual work, foods such as small yellow-fin tuna, dried small shrimps, squills, crabs, mothers suffering from gastric diseases, spouse alive, use of refrigerators and hot food, etc. According to some principles and methods of probability and fuzzy mathematics, a quantitative assessment model was established as follows: first, we selected some factors significant in statistics, and calculated weight coefficient for each one by two different methods; second, population space was divided into gastric cancer fuzzy subset and non gastric cancer fuzzy subset, then a mathematic model for each subset was established, we got a mathematic expression of attribute degree (AD).

RESULTS: Based on the data of 63 patients and 693 normal people, AD of each subject was calculated. Considering the sensitivity and specificity, the thresholds of AD values calculated were configured with 0.20 and 0.17, respectively. According to these thresholds, the sensitivity and specificity of the quantitative model were about 69% and 63%. Moreover, statistical test showed that the identification outcomes of these two different calculation methods were identical (P>0.05).

CONCLUSION: The validity of this method is satisfactory. It is convenient, feasible, economic and can be used to determine individual and population risks of gastric cancer.

Upregulated Akt signaling adjacent to gastric cancers: implications for screening and chemoprevention

Most gastric adenocarcinomas arise as a longterm complication of Helicobacter pylori infection of the stomach, but the high prevalence of this infection limits the cost-effectiveness of antibiotic eradication as a cancer prevention strategy. Here we have used phosphorylation-specific antibodies against the Akt kinase consensus sequence to detect downstream substrates of this oncogenic signaling pathway in normal and malignant gastric tissues. In vitro studies confirm that phosphorylation of Akt and its substrates is inducible by epithelial mitogens such as epidermal growth factor (EGF), which is implicated in the pathogenesis of H. pylori gastritis. Control clinical studies confirm far stronger Akt substrate phosphorylation in primary human breast cancers than in matched adjacent normal breast tissues; unexpectedly, however, increased Akt signaling is apparent in both primary stomach cancers and adjacent normal gastric tissues. These findings raise the possibility of a preneoplastic field defect induced in morphologically normal tissues, and suggest that immunoassays of mucosal Akt activity could guide preventive surveillance and/or intervention in patients at risk of gastric cancer. Moreover, since recent reports confirm Akt inhibition by COX-2 inhibitors, these data support the chemopreventive efficacy of such drugs for at-risk individuals.

Major factors affecting the emergence and re-emergence of infectious diseases

The diversity of infectious disease threats currently facing humanity is unprecedented because of the remarkable emergence and reemergence of pathogens worldwide. Because of population mobility, globalization of commerce and the food supply, and the effects of the HIV/AIDS pandemic, infections in the developing world must be addressed to prevent infections in industrialized countries. Because pathogens do not recognize national boundaries, the rapidity with which individuals can circumnavigate the globe incubating infections makes the control of communicable diseases an enormous challenge for governments as well as for the public and primary health care systems. A global strategy for dealing with infectious disease threats must be developed and implemented as soon as possible.