Cost-effectiveness of the Three I's for HIV/TB and ART to prevent TB among people living with HIV

Implementation of systematic screening for tuberculosis disease and tuberculosis preventive treatment among people living with HIV attending antiretroviral treatment clinics in Ghana: a national pilot study

OBJECTIVES

To assess the yield and cost of implementing systematic screening for tuberculosis (TB) disease among people living with HIV (PLHIV) and initiation of TB preventive treatment (TPT) in Ghana.

DESIGN

Prospective cohort study from August 2019 to December 2020.

SETTING

One hospital from each of Ghana's regions (10 total).

PARTICIPANTS

Any PLHIV already receiving or newly initiating antiretroviral treatment were eligible for inclusion.

INTERVENTIONS

All participants received TB symptom screening and chest radiography. Those with symptoms and/or an abnormal chest X-ray provided a sputum sample for microbiological testing. All without TB disease were offered TPT.

PRIMARY AND SECONDARY OUTCOME MEASURES

We estimated the proportion diagnosed with TB disease and proportion initiating TPT. We used logistic regression to identify factors associated with TB disease diagnosis. We used microcosting to estimate the health system cost per person screened (2020 US$).

RESULTS

Of 12 916 PLHIV attending participating clinics, 2639 (20%) were enrolled in the study and screened for TB disease. Overall, 341/2639 (12.9%, 95% CI 11.7% to 14.3%) had TB symptoms and/or an abnormal chest X-ray; 50/2639 (1.9%; 95% CI 1.4% to 2.5%) were diagnosed with TB disease, 20% of which was subclinical. In multivariable analysis, only those newly initiating antiretroviral treatment were at increased odds of TB disease (adjusted OR 4.1, 95% CI 2.0 to 8.2). Among 2589 participants without TB, 2581/2589 (99.7%) initiated TPT. Overall, the average cost per person screened during the study was US$57.32.

CONCLUSION

In Ghana, systematic TB disease screening among PLHIV was of high yield and modest cost when combined with TPT. Our findings support WHO recommendations for routine TB disease screening among PLHIV.

Economic and modeling evidence for tuberculosis preventive therapy among people living with HIV: A systematic review and meta-analysis

BACKGROUND

Human immunodeficiency virus (HIV) is the strongest known risk factor for tuberculosis (TB) through its impairment of T-cell immunity. Tuberculosis preventive treatment (TPT) is recommended for people living with HIV (PLHIV) by the World Health Organization, as it significantly reduces the risk of developing TB disease. We conducted a systematic review and meta-analysis of modeling studies to summarize projected costs, risks, benefits, and impacts of TPT use among PLHIV on TB-related outcomes.

METHODS AND FINDINGS

We searched MEDLINE, Embase, and Web of Science from inception until December 31, 2020. Two reviewers independently screened titles, abstracts, and full texts; extracted data; and assessed quality. Extracted data were summarized using descriptive analysis. We performed quantile regression and random effects meta-analysis to describe trends in cost, effectiveness, and cost-effectiveness outcomes across studies and identified key determinants of these outcomes. Our search identified 6,615 titles; 61 full texts were included in the final review. Of the 61 included studies, 31 reported both cost and effectiveness outcomes. A total of 41 were set in low- and middle-income countries (LMICs), while 12 were set in high-income countries (HICs); 2 were set in both. Most studies considered isoniazid (INH)-based regimens 6 to 2 months long (n = 45), or longer than 12 months (n = 11). Model parameters and assumptions varied widely between studies. Despite this, all studies found that providing TPT to PLHIV was predicted to be effective at averting TB disease. No TPT regimen was substantially more effective at averting TB disease than any other. The cost of providing TPT and subsequent downstream costs (e.g. post-TPT health systems costs) were estimated to be less than $1,500 (2020 USD) per person in 85% of studies that reported cost outcomes (n = 36), regardless of study setting. All cost-effectiveness analyses concluded that providing TPT to PLHIV was potentially cost-effective compared to not providing TPT. In quantitative analyses, country income classification, consideration of antiretroviral therapy (ART) use, and TPT regimen use significantly impacted cost-effectiveness. Studies evaluating TPT in HICs suggested that TPT may be more effective at preventing TB disease than studies evaluating TPT in LMICs; pooled incremental net monetary benefit, given a willingness-to-pay threshold of country-level per capita gross domestic product (GDP), was $271 in LMICs (95% confidence interval [CI] -$81 to $622, p = 0.12) and was $2,568 in HICs (-$32,115 to $37,251, p = 0.52). Similarly, TPT appeared to be more effective at averting TB disease in HICs; pooled percent reduction in active TB incidence was 20% (13% to 27%, p < 0.001) in LMICs and 37% (-34% to 100%, p = 0.13) in HICs. Key limitations of this review included the heterogeneity of input parameters and assumptions from included studies, which limited pooling of effect estimates, inconsistent reporting of model parameters, which limited sample sizes of quantitative analyses, and database bias toward English publications.

CONCLUSIONS

The body of literature related to modeling TPT among PLHIV is large and heterogeneous, making comparisons across studies difficult. Despite this variability, all studies in all settings concluded that providing TPT to PLHIV is potentially effective and cost-effective for preventing TB disease.

TB and HIV Epidemiology and Collaborative Service: Evidence from Ethiopia, 2011-2015

Background

Integrating and scaling up tuberculosis (TB) and HIV services are essential strategies to achieve the combined goals ending both TB and HIV, especially in TB and HIV high burden countries. This study aimed to examine the prevalence of TB and HIV co-infection and the implementation of collaborative services in Ethiopia.

Methods

We used a national sentinel surveillance TB/HIV co-infection collected between 2010 and 2015. The Ethiopian Public Health Institute collected and collated the data quarterly from 79 health facilities in nine regional states and two city administrations.

Results

A total of 55,336 people living with HIV/AIDS were screened for active TB between 2011 and 2015. Of these, 7.3% were found co-infected with TB, and 13% TB-negative PLWHA were on isoniazid preventive therapy. Nine out of ten (89.2%) active TB patients were screened for HIV counselling and 17.8% were found to be HIV positive; 78.2% and 53.0% of HIV/TB co-infected patients were receiving cotrimoxazole preventive therapy and antiretroviral treatment, respectively.

Conclusion

This study showed that the prevalence of TB and HIV co-infection failed to decrease over the study period, and that, while there was an increasing trend for integration of collaborative services, this was not uniform over time. Aligning and integrating TB and HIV responses are still needed to achieve the target of ending TB and HIV by 2030.

Cost-effectiveness analysis of Xpert in detecting Mycobacterium tuberculosis: A systematic review

OBJECTIVES

To report the cost-effectiveness of Xpert in detecting Mycobacterium tuberculosis (MTB) through a comprehensive systematic review.

METHODS

Specialized bibliographic databases were searched. Study quality was evaluated by commonly-used industry standards. Due to heterogeneity, evidences were synthesized narratively.

RESULTS

Four studies from intermediate-to-low tuberculosis (TB)-burdern areas and 17 studies from high-TB-burden areas were included. Smear microscopy, clinical diagnosis and chest radiography were mostly used for comparison. Cost elements varied considerably depending on the perspectives. Cost-effectiveness and cost-utility analyses were used by seven and fourteen studies, respectively. All studies were of high quality (CHEERS score of 78.4 and QHES score of 86.9). Average cost per test was 29.8 US$ for Xpert compared with 3.83 US$ for smear microscopy. Cost-effectiveness analyses mostly supported application of Xpert into areas under varying TB burdens.

CONCLUSIONS

Xpert seems cost-effective under respective willingness-to-pay thresholds in nations with differences in socioeconomy, HIV stress and geographical distribution. Nevertheless, policymakers will benefit from localized studies since regional economic/financial statuses and health-care system should also be considered apart from the reports of cost-effectiveness.

Tuberculosis infection control practices in a high-burden metro in South Africa: A perpetual bane for efficient primary health care service delivery

Background

Tuberculosis (TB) prevention, including infection control, is a key element in the strategy to end the global TB epidemic. While effective infection control requires all health system components to function well, this is an area that has not received sufficient attention in South Africa despite the availability of policy and guidelines.

Aim

To describe the state of implementation of TB infection control measures in a high-burden metro in South Africa.

Setting

The research was undertaken in a high TB- and HIV-burdened metropolitan area of South Africa. More specifically, the study sites were primary health care facilities (PHC), that among other services also diagnosed TB.

Methods

A cross-sectional survey, focusing on the World Health Organization levels of infection control, which included structured interviews with nurses providing TB diagnosis and treatment services as well as observations, at all 41 PHC facilities in a high TB-burdened and HIV-burdened metro of South Africa.

Results

Tuberculosis infection control was poorly implemented, with few facilities scoring 80% and above on compliance with infection control measures. Facility controls: 26 facilities (63.4%) had an infection control committee and 12 (29.3%) had a written infection control plan. Administrative controls: 26 facilities (63.4%) reported separating coughing and non-coughing patients, while observations revealed that only 11 facilities (26.8%) had separate waiting areas for (presumptive) TB patients. Environmental controls: most facilities used open windows for ventilation (n = 30; 73.2%); however, on the day of the visit, only 12 facilities (30.3%) had open windows in consulting rooms. Personal protective equipment: 9 facilities (22%) did not have any disposable respirators in stock and only 9 respondents (22%) had undergone fit testing. The most frequently reported barrier to implementing good TB infection control practices was lack of equipment (n = 22; 40%) such as masks and disposable respirators, as well as the structure or layout of the PHC facilities. The main recommendation to improve TB infection control was education for patients and health care workers (n = 18; 33.3%).

Conclusion

All levels of the health care system should be engaged to address TB prevention and infection control in PHC facilities. Improved infection control will address the nosocomial spread of TB in health facilities and keep health care workers and patients safe from infection.

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 Community-Based TB/HIV Screening and Linkage to Care in Rural South Africa

South Africa has one of the highest burdens of TB worldwide, driven by the country's widespread prevalence of HIV, and further complicated by drug resistance. Active case finding within the community, particularly in rural areas where healthcare access is limited, can significantly improve diagnosis and treatment coverage in high-incidence settings. We evaluated the potential health and economic consequences of implementing community-based TB/HIV screening and linkage to care. Using a dynamic model of TB and HIV transmission over a time horizon of 10 years, we compared status quo TB/HIV control to community-based TB/HIV screening at frequencies of once every two years, one year, and six months. We also considered the impact of extending IPT from 36 months for TST positive and 12 months for TST negative or unknown patients (36/12) to lifetime use for all HIV-infected patients. We conducted a probabilistic sensitivity analysis to assess the effect of parameter uncertainty on the cost-effectiveness results. We identified four strategies that saved the most life years for a given outlay: status quo TB/HIV control with 36/12 months of IPT and TB/HIV screening strategies at frequencies of once every two years, one year, and six months with lifetime IPT. All of these strategies were very cost-effective at a threshold of $6,618 per life year saved (the per capita GDP of South Africa). Community-based TB/HIV screening with linkage to care is therefore very cost-effective in rural South Africa.

Clinical Correlates and Drug Resistance in HIV-Infected and -Uninfected Pulmonary Tuberculosis Patients in South India

OBJECTIVES

To examine demographics, clinical correlates, sputum AFB (acid fast bacilli) smear grading DOTS (Directly Observed Therapy Short Course) uptake, and drug resistance in a cohort of newly-diagnosed, smear positive pulmonary tuberculosis (TB) patients with respect to HIV status at baseline, and compare smear conversion rates, side effects and mortality after two months.

DESIGN

A prospective study among 54 HIV positive and 41 HIV negative pulmonary TB patients. Data were collected via face-to-face interviews, review of medical records, and lab tests.

RESULTS

HIVTB co-infected patients, though more symptomatic at baseline, showed more improvement in their symptoms compared to HIV-uninfected TB patients at follow-up. The HIV co-infected group had more prevalent perceived side effects, and sputum smear positivity was marginally higher compared to the HIV negative group at follow-up. Mortality was higher among the HIV-infected group. Both groups had high rates of resistance to first-line anti-tubercular drugs, particularly isoniazid. There was no significant difference in the drug resistance patterns between the groups.

CONCLUSIONS

Prompt initiation and provision of daily regimens of ATT (Anti-Tubercular treatment) along with ART (Anti-Retroviral treatment) via ART centers is urgently needed in India. As resistance to ART and/or ATT is directly linked to medication non-adherence, the use of counseling, regular reinforcement, early detection and appropriate intervention strategies to tackle this complex issue could help prevent premature mortality and development of resistance in HIV-TB co-infected patients. The high rate of isoniazid resistance might preclude its use in India as prophylaxis for latent TB in HIV infected persons as per the World Health Organization (WHO) guideline.