Cost-Effectiveness of isoniazid preventive therapy among HIV-infected patients clinicaly screened for latent tuberculosis infection in Dar es Salaam, Tanzania: A prospective Cohort study.

BACKGROUND: One of the reasons why Isoniazid preventive therapy (IPT) for Tuberculosis (TB) is not widely used in low income countries is concerns on cost of excluding active TB. We analyzed the cost-effectiveness of IPT provision in Tanzania having ruled out active TB by a symptom-based screening tool. METHODS: Data on IPT cost-effectiveness was prospectively collected from an observational cohort study of 1283 HIV-infected patients on IPT and 1281 controls; followed up for 24 months. The time horizon for the analysis was 2 years. Number of TB cases prevented and deaths averted were used for effectiveness. A micro costing approach was used from a provider perspective. Cost was estimated on the basis of clinical records, market price or interviews with medical staff. We annualized the cost at a discount of 3%. A univariate sensitivity analysis was done. Results are presented in US$ at an average annual exchange rate for the year 2012 which was Tanzania shillings 1562.4 for 1 US $. RESULTS: The number of TB cases prevented was 420/100,000 persons receiving IPT. The number of deaths averted was 979/100,000 persons receiving IPT. Incremental cost due to IPT provision was US$ 170,490. The incremental cost effective ratio was US $ 405.93 per TB case prevented and US $ 174.15 per death averted. These costs were less than 3 times the 768 US $ Gross Domestic Product (GDP) per capita for Tanzania in the year 2014, making IPT provision after ruling out active TB by the symptom-based screening tool cost-effective. The results were robust to changes in laboratory and radiological tests but not to changes in recurrent, personnel, medication and utility costs. CONCLUSION: IPT should be given to HIV-infected patients who screen negative to symptom-based TB screening questionnaire. Its cost-effectiveness supports government policy to integrate IPT to HIV/AIDS care and treatment in the country, given the availability of budget and the capacity of health facilities.

Cost-effectiveness of tuberculosis screening and isoniazid treatment in the TB/HIV in Rio (THRio) Study.

OBJECTIVE: To estimate the incremental cost-effectiveness of tuberculosis (TB) screening and isoniazid preventive therapy (IPT) among human immunodeficiency virus (HIV) infected adults in Rio de Janeiro, Brazil. DESIGN: We used decision analysis, populated by data from a cluster-randomized trial, to project the costs (in 2010 USD) and effectiveness (in disability-adjusted life years [DALYs] averted) of training health care workers to implement the tuberculin skin test (TST), followed by IPT for TST-positive patients with no evidence of active TB. This intervention was compared to a baseline of usual care. We used time horizons of 1 year for the intervention and 20 years for disease outcomes, with all future DALYs and medical costs discounted at 3% per year. RESULTS: Providing this intervention to 100 people would avert 1.14 discounted DALYs (1.57 undiscounted DALYs). The median estimated incremental cost-effectiveness ratio was $2273 (IQR $1779-$3135) per DALY averted, less than Brazil's 2010 per capita gross domestic product (GDP) of $11,700. Results were most sensitive to the cost of providing the training. CONCLUSION: Training health care workers to screen HIV-infected adults with TST and provide IPT to those with latent tuberculous infection can be considered cost-effective relative to the Brazilian GDP per capita.

Current treatment options for latent tuberculosis infection.

Treatment of latent tuberculosis infection (LTBI) is a key component in TB control strategies worldwide. However, as people with LTBI are neither symptomatic nor contagious, any screening decision should be weighed carefully against the potential benefit of preventing active disease in those who are known to be at higher risk and are willing to accept therapy for LTBI. This means that a targeted approach is desirable to maximize cost effectiveness and to guarantee patient adherence. We focus on LTBI treatment strategies in patient populations at increased risk of developing active TB, including candidates for treatment with tumor necrosis factor-α blockers. In the last 40 years, isoniazid (INH) has represented the keystone of LTBI therapy across the world. Although INH remains the first therapeutic option, alternative treatments that are effective and associated with increased adherence and economic savings are available. Current recommendations, toxicity, compliance, and cost issues are discussed in detail in this review. A balanced relationship between the patient and healthcare provider could increase adherence, while cost-saving treatment strategies with higher effectiveness, fewer side effects, and of shorter duration should be offered as preferred.

Management of children exposed to Mycobacterium tuberculosis: a public health evaluation in West Java, Indonesia.

OBJECTIVE: To investigate qualitatively and quantitatively the performance of a programme for managing the child contacts of adult tuberculosis patients in Indonesia. METHODS: A public health evaluation framework was used to assess gaps in a child contact management programme at a lung clinic. Targets for programme performance indicators were derived from established programme indicator targets, the scientific literature and expert opinion. Compliance with tuberculosis screening, the initiation of isoniazid preventive therapy in children younger than 5 years, the accuracy of tuberculosis diagnosis and adherence to preventive therapy were assessed in 755 child contacts in two cohorts. In addition, 22 primary caregivers and 34 clinic staff were interviewed to evaluate knowledge and acceptance of child contact management. The cost to caregivers was recorded. Gaps between observed and target indicator values were quantified. FINDINGS: THE GAPS BETWEEN OBSERVED AND TARGET PERFORMANCE INDICATORS WERE: 82% for screening compliance; 64 to 100% for diagnostic accuracy, 50% for the initiation of preventive therapy, 54% for adherence to therapy and 50% for costs. Many staff did not have adequate knowledge of, or an appropriate attitude towards, child contact management, especially regarding isoniazid preventive therapy. Caregivers had good knowledge of screening but not of preventive therapy and had difficulty travelling to the clinic and paying costs. CONCLUSION: The study identified widespread gaps in the performance of a child contact management system in Indonesia, all of which appear amenable to intervention. The public health evaluation framework used could be applied in other settings where child contact management is failing.

Enhanced cost-benefit analysis of strategies for LTBI screening and INH chemoprevention in Germany.

OBJECTIVES: There is only limited economic data in head-to head comparison between a whole blood QuantiFERON TB Gold in tube (QFT) and the tuberculin skin test (TST) when screening and treating for latent tuberculosis infection (LTBI), and no published study to date that takes into account the predictive value of the two tests. METHODS: Health and economic outcomes of isoniazid preventive treatment (IPT) of close contacts were compared in a decision tree model to perform a cost-benefit analysis with respect to isoniazid related hepatotoxicity and early post-exposure TB over a 2-y period, using the QFT or TST alone or QFT as a confirmatory test for TST results. RESULTS: Cost of screening and treating for using the QFT alone amounted to euro215.79 per close contact, less than that of dual step-testing (euro227.89) or using TST alone (euro232.58). Savings amounted to euro12,200 or euro16,791 per 1000 close contacts, respectively. QFT based procedures were most sensitive to low compliance with IPT or increasing price. Costs of dual step screening was mostly influenced by cost of treating TB disease. When the progression rate for QFT was lowered to that for the TST in a sensitivity analysis, the relationship between the strategies remained robust. In addition, costs of the QFT strategy decreased to euro165.1, and those of the dual step strategy to euro218.4. CONCLUSION: IPT on the basis of using the QFT assay alone produces less cost and reduces more TB cases than other strategies in a low-incidence setting. These data have implications for the rational implementation of screening strategies in contact investigation.

Cost-effectiveness of isoniazid chemoprevention in close contacts.

The aim of the present study was to perform a cost-effectiveness analysis in young and middle-aged adults with latent tuberculosis (TB) infection in Germany. A Markov model simulated the progression of 20- and 40-yr-old close contacts of active TB cases over 20 yrs. Health and economic outcomes of isoniazid (INH) chemoprevention versus no intervention were compared. The analysis determined the incremental cost-effectiveness ratio in terms of cost per quality-adjusted life year and the difference between numbers of TB cases and of TB-related deaths. INH chemoprevention prevented 79% of expected TB cases in both age groups, and saved 9,482 and 9,142 in the lower and higher age groups, respectively, per case prevented. Quality-adjusted life expectancy was slightly extended by 8 days in the lower age group and 7 days in the higher age group, at a cost saving of 417 and 375, respectively, per person. Annual savings were 20,862 and 18,742 per 1,000 contacts, respectively. The number needed to be treated to prevent one TB case in the lower age group was 23 and 25 in the higher age group. The programme also prevented three TB-related deaths in the younger and two in the older cohort. The results are highly sensitive to treatment-cost assumptions. In conclusion, isoniazid chemoprevention in Germany is a highly cost-effective approach for reducing the burden of tuberculosis in recently converted young and middle-aged adults.

Latent tuberculosis in pregnancy: screening and treatment.

Currently, most cases of active tuberculosis in the United States are a result of activation of latent tuberculosis infection. In this article, the history of the epidemiology of tuberculosis and latent tuberculosis infection is reviewed. Previous and current recommendations for screening and treatment for latent tuberculosis during pregnancy and the postpartum period are discussed. A review of the literature regarding postpartum and antepartum treatment is included. Finally, the question of whether antepartum or postpartum treatment is the most beneficial is discussed.

Cost-effectiveness of tuberculosis screening and observed preventive therapy for active drug injectors at a syringe-exchange program.

This study examined whether costs associated with tuberculosis (TB) screening and directly observed preventive therapy (DOPT) among drug injectors attending a syringe exchange are justified by cases and costs of active TB cases prevented and examined the impact of monetary incentives to promote adherence on cost-effectiveness. We examined program costs and projected savings using observed adherence and prevalence rates and literature estimates of isoniazid (INH) preventive therapy efficacy, expected INH hepatoxicity rates, and TB treatment costs; we conducted sensitivity analyses for a range of INH effectiveness, chest X-ray (CXR) referral adherence, and different strategies regarding anergy among persons affected with human immunodeficiency virus (HIV). For 1,000 patients offered screening, incorporating real observed program adherence rates, the program would avert $179,934 in TB treatment costs, for a net savings of $123,081. Assuming a modest risk of TB among HIV-infected anergic persons, all strategies with regard to anergy were cost saving, and the strategy of not screening for anergy and not providing DOPT to HIV-infected anergic persons resulted in the greatest cost savings. If an incentive of $25 per person increased CXR adherence from the observed 31% to 50% or 100%, over a 5-year follow-up the net cost savings would increase to $170,054 and $414,856, respectively. In this model, TB screening and DOPT at a syringe exchange is a cost-effective intervention and is cost-saving compared to costs of treating active TB cases that would have occurred in the absence of the intervention. This model is useful in evaluating the cost impact of planned program refinements, which can then be tested. Monetary incentives for those referred for screening CXRs would be justified on a cost basis if they had even a modest beneficial impact on adherence.

The cost-effectiveness of evidence-based guidelines and practice for screening and prevention of tuberculosis.

INTRODUCTION: The potential cost-effectiveness of screening depends on the risk of tuberculosis (TB) in the population being screened and the rate at which the screening outcome (prevention) is achieved. AIMS: To compare the cost-effectiveness of contact screening for TB for: (1) contact screening as it actually occurred in Victoria in 1991 (Model 1); (2) the process which should have occurred had the 1991 contact screening guidelines been followed (Model 2); (3) a hypothetical evidence-based model (Model 3). METHODS: Three models were constructed according to the aims. The cost-effectiveness of contact screening is presented as costs to government per unit outcome (in the form of cases prevented, cases found and contacts traced) for each model. Assumptions about disease behaviour were consistent between models. A sensitivity analysis was performed to examine the effect of the assumptions made in Model 3 about rates of referral and treatment of infected contacts, and about the efficacy of isoniazid (INH) in preventing TB. RESULTS: The total cost of Model 1 was greater than that of the other Models. Model 1 is the least cost-effective, costing $309 065 per case prevented, and Model 3 is the most cost-effective, costing $32 210 per case prevented. The cost of Model 2 was $58 742 per case prevented. The incremental cost-effectiveness of Model 3 compared to Model 2 is $107 per additional contact screened, and $3881 per additional case prevented. Case finding is not as cost-effective as best-practice case prevention, ranging from $231 799 per case found in Model 1 to $205 596 per case found in Model 2. The sensitivity analysis shows that the cost-effectiveness of Model 3 decreases with lower referral rates, lower rates of preventive therapy, and lower efficacy of INH. However, even allowing for reduced programme parameters, Model 3 is most cost-effective. DISCUSSION: Costing policy options is an important component of programme delivery, but needs to be considered in the context of the product being purchased, e.g. the prevention of disease, or case finding. Case finding as a product of contact screening is expensive in all three models. Prevention of TB, on the other hand, can be cost-effective, as shown in Model 3. It was least cost-effective in Model 1, largely because prevention was not considered a priority, and few infected contacts actually received preventive therapy. Clear programme aims, adherence to guidelines and high rates of preventive therapy are essential in order to achieve cost-effectiveness.

[Cost effectiveness analysis of isoniazid preventive therapy to the contacts of tuberculosis patients under Japanese settings].

The target for isoniazid preventive therapy against tuberculosis in Japan has been contact persons of tuberculosis patients with the age of less than 30. This paper discusses about the cost effectiveness analysis of preventive therapy with the mathematical model. The effectiveness was measured with averted tuberculosis cases, averted death, averted loss of DALY (disability adjusted life years), averted loss of healthy years of life. With all indicators, isoniazid preventive therapy was effective if preventive chemotherapy is given to persons younger than 70 years old and with the higher probability of new infection than 20%, and if it is given following the present criteria of tuberculin testing for preventive therapy in Japan. The total medical cost is cheaper among persons with the preventive therapy than those without the preventive therapy, if the probability of new infection among the contact persons is more than 29% at the age of 40. The isoniazid preventive therapy for health care workers, whose prevalence of infection is higher than the average population, was also effective in both cases with and without baseline tuberculin testing. However, the positive predictive value of criteria of preventive therapy highly depends on the probability of new infection.