Timing of default from tuberculosis treatment: a systematic review

Economic implications of novel regimens for tuberculosis treatment in three high-burden countries: a modelling analysis

BACKGROUND

With numerous trials investigating novel drug combinations to treat tuberculosis, we aimed to evaluate the extent to which future improvements in tuberculosis treatment regimens could offset potential increases in drug costs.

METHODS

In this modelling analysis, we used an ingredients-based approach to estimate prices at which novel regimens for rifampin-susceptible and rifampin-resistant tuberculosis treatment would be cost-neutral or cost-effective compared with standards of care in India, the Philippines, and South Africa. We modelled regimens meeting targets set in the WHO's 2023 Target Regimen Profiles (TRPs). Our decision-analytical model tracked cohorts of adults initiating rifampin-susceptible or rifampin-resistant tuberculosis treatment, simulating their health outcomes and costs accumulated during and following treatment under standard-of-care and novel regimen scenarios. Price thresholds included short-term cost-neutrality (considering only savings accrued during treatment), medium-term cost-neutrality (additionally considering savings from averted retreatments and secondary cases), and cost-effectiveness (incorporating willingness-to-pay for improved health outcomes).

FINDINGS

Total medium-term costs per person treated using standard-of-care regimens were estimated at US$450 (95% uncertainty interval 310-630) in India, $560 (350-860) in the Philippines, and $730 (530-1090) in South Africa for rifampin-susceptible tuberculosis (current drug costs $46) and $2100 (1590-2810) in India, $2610 (2090-3280) in the Philippines, and $3790 (3090-4630) in South Africa for rifampin-resistant tuberculosis (current drug costs $432). A rifampin-susceptible tuberculosis regimen meeting the optimal targets defined in the TRPs could be cost-neutral in the short term at drug costs of $140 (90-210) per full course in India, $230 (130-380) in the Philippines, and $280 (180-460) in South Africa. For rifampin-resistant tuberculosis, short-term cost-neutral thresholds were higher with $930 (720-1230) in India, $1180 (980-1430) in the Philippines, and $1480 (1230-1780) in South Africa. Medium-term cost-neutral prices were approximately $50-100 higher than short-term cost-neutral prices for rifampin-susceptible tuberculosis and $250-550 higher for rifampin-resistant tuberculosis. Health system cost-neutral prices that excluded patient-borne costs were 45-70% lower (rifampin-susceptible regimens) and 15-50% lower (rifampin-resistant regimens) than the cost-neutral prices that included patient costs. Cost-effective prices were substantially higher. Shorter duration was the most important driver of medium-term savings with novel regimens, followed by ease of adherence.

INTERPRETATION

Improved tuberculosis regimens, particularly shorter regimens or those that facilitate better adherence, could reduce overall costs, potentially offsetting higher prices.

FUNDING

WHO.

Quantifying non-adherence to anti-tuberculosis treatment due to early discontinuation: a systematic literature review of timings to loss to follow-up

BACKGROUND

The burden of non-adherence to anti-tuberculosis (TB) treatment is poorly understood. One type is early discontinuation, that is, stopping treatment early. Given the implications of early discontinuation for treatment outcomes, we undertook a systematic review to estimate its burden, using the timing of loss to follow-up (LFU) as a proxy measure.

METHODS

Web of Science, Embase and Medline were searched up to 14 January 2021 using terms covering LFU, TB and treatment. Studies of adults (≥ 18 years) on the standard regimen for drug-sensitive TB reporting the timing of LFU (WHO definition) were included. A narrative synthesis was conducted and quality assessment undertaken using an adapted version of Downs and Black. Papers were grouped by the percentage of those who were ultimately LFU who were LFU by 2 months. Three groups were created: <28.3% LFU by 2 months, ≥28.3-<38.3%, ≥38.3%). The percentage of dose-months missed due to early discontinuation among (1) those LFU, and (2) all patients was calculated.

RESULTS

We found 40 relevant studies from 21 countries. The timing of LFU was variable within and between countries. 36/40 papers (90.0%) reported the percentage of patients LFU by the end of 2 months. 31/36 studies (86.1%) reported a higher than or as expected percentage of patients becoming LFU by 2 months. The percentage of dose-months missed by patients who became LFU ranged between 37% and 77% (equivalent to 2.2-4.6 months). Among all patients, the percentage of dose-months missed ranged between 1% and 22% (equivalent to 0.1-1.3 months).

CONCLUSIONS

A larger than expected percentage of patients became LFU within the first 2 months of treatment. These patients missed high percentages of dose months of treatment due to early discontinuation. Interventions to promote adherence and retain patients in care must not neglect the early months of treatment.

PROSPERO REGISTRATION NUMBER

CRD42021218636.

Prevalence and predictive factors of tuberculosis treatment interruption in the Asia region: a systematic review and meta-analysis

INTRODUCTION

Tuberculosis (TB) treatment interruption remains a critical challenge leading to poor treatment outcomes. Two-thirds of global new TB cases are mostly contributed by Asian countries, prompting systematic analysis of predictors for treatment interruption due to the variable findings.

METHODS

Articles published from 2012 to 2021 were searched through seven databases. Studies that established the relationship for risk factors of TB treatment interruption among adult Asian were included. Relevant articles were screened, extracted and appraised using Joanna Briggs Institute's checklists for cohort, case-control and cross-sectional study designs by three reviewers. Meta-analysis was performed using the random effect model in Review Manager software. The pooled prevalence and predictors of treatment interruption were expressed in ORs with 95% CIs; heterogeneity was assessed using the I₂ statistic. The publication bias was visually inspected using the funnel plot.

RESULTS

Fifty eligible studies (658 304 participants) from 17 Asian countries were included. The overall pooled prevalence of treatment interruption was 17% (95% CI 16% to 18%), the highest in Southern Asia (22% (95% CI 16% to 29%)), followed by Eastern Asia (18% (95% CI 16% to 20%)) and South East Asia (16% (95% CI 4% to 28%)). Seven predictors were identified to increase the risk of treatment interruption, namely, male gender (OR 1.38 (95% CI 1.26 to 1.51)), employment (OR 1.43 (95% CI 1.11 to 1.84)), alcohol intake (OR 2.24 (95% CI 1.58 to 3.18)), smoking (OR 2.74 (95% CI 1.98 to 3.78)), HIV-positive (OR 1.50 (95% CI 1.15 to 1.96)), adverse drug reactions (OR 2.01 (95% CI 1.20 to 3.34)) and previously treated cases (OR 1.77 (95% CI 1.39 to 2.26)). All predictors demonstrated substantial heterogeneity except employment and HIV status with no publication bias.

CONCLUSION

The identification of predictors for TB treatment interruption enables strategised planning and collective intervention to be targeted at the high-risk groups to strengthen TB care and control in the Asia region.

Risk factors for early TB treatment interruption among newly diagnosed patients in Malaysia

TB treatment interruption has resulted in delayed sputum conversion, drug resistance, and a high mortality rate and a prolonged treatment course, hence leading to economic and psychosocial affliction. To date, there are limited studies investigating the physico-social risk factors for early treatment interruptions. This prospective multicenter cohort study aimed to investigate the risk factors for early treatment interruption among new pulmonary tuberculosis (TB) smear-positive patients in Selangor, Malaysia. A total of 439 participants were recruited from 39 public treatment centres, 2018–2019. Multivariate Cox proportional hazard analyses were performed to analyse the risk factors for early treatment interruption. Of 439 participants, 104 (23.7%) had early treatment interruption, with 67.3% of early treatment interruption occurring in the first month of treatment. Being a current smoker and having a history of hospitalization, internalized stigma, low TB symptoms score, and waiting time spent at Directly Observed Treatment, Short-course centre were risk factors for early treatment interruption. An appropriate treatment adherence strategy is suggested to prioritize the high-risk group with high early treatment interruption. Efforts to quit smoking cessation programs and to promote stigma reduction interventions are crucial to reduce the probability of early treatment interruption.

The impact of the stratification by degree of clinical severity and abandonment risk of tuberculosis treatment

Objective:

Evaluate the impact of the instrument of the “Stratification by Degree of Clinical Severity and Abandonment Risk of Tuberculosis Treatment” (SRTB) on the tuberculosis outcome.

Methods:

This study was a pragmatic clinical trial involving patients with a confirmed diagnosis of tuberculosis treated at one of the 152 primary health care units in the city of Belo Horizonte, Brazil, between May of 2016 and April of 2017. Cluster areas for tuberculosis were identified, and the units and their respective patients were divided into intervention (use of SRTB) and nonintervention groups.

Results:

The total sample comprised 432 participants, 223 and 209 of whom being allocated to the nonintervention and intervention groups, respectively. The risk of treatment abandonment in the nonintervention group was significantly higher than was that in the intervention group (OR = 15.010; p < 0.001), regardless of the number of risk factors identified. Kaplan-Meier curves showed a hazard ratio of 0.0753 (p < 0.001).

Conclusions:

The SRTB instrument was effective in reducing abandonment of tuberculosis treatment, regardless of the number of risk factors for that. This instrument is rapid and easy to use, and can be adapted to different realities. Its application showed characteristics predisposing to a non-adherence to the treatment and established bases to mitigate its impact.

A 20-year retrospective study of osteoarticular tuberculosis in a pediatric third level referral center

Purpose

The objective of the present study is to describe the clinical, diagnostic, radiological and therapeutic aspects of osteoarticular tuberculosis (OATB) in patients in a tertiary pediatric hospital, to know if the diagnosis of OATB in pediatrics is a challenge due to its insidious clinical presentation.

Methods

A retrospective, descriptive study of the cases of Tuberculosis (TB) in children was carried out. A total of 159 cases met the condition for the analysis.

Results

The most frequent TB modality was extrapulmonary in 85%. Out of this, only 29% was OATB. The mean age was 4.9 years (range 8 months–16 years). Eighty-six per cent of cases received Bacille Calmette-Guérin (BCG) vaccination at birth. Median time of symptoms prior to diagnosis was 8 months. Microbiological confirmation was achieved only in five cases, with a high sensitivity to the antimicrobial treatment. Mycobacterium bovis BCG strain Tokio 172 was confirmed in three cases. Mortality rate was 0% during the time of study

Conclusion

Our study describes the epidemiological characteristics of OATB cases in Mexican children. This data revealed a high prevalence of bone and joint TB infection. Pediatric OATB should be considered in cases with lytic bone lesions, fever and local pain. In countries with BCG immunization program, M. bovis should not be forgotten as an etiological agent. The low detection rate with one technique approach highlights the urgent need for more sensitive test to diagnose OATB in children.

Pretomanid Pharmacokinetics in the Presence of Rifamycins: Interim Results from a Randomized Trial among Patients with Tuberculosis

Shorter, more potent regimens are needed for tuberculosis. The nitroimidazole pretomanid was recently approved for extensively drug-resistant tuberculosis in combination with bedaquiline and linezolid. Pretomanid may also have benefit as a treatment-shortening agent for drug-sensitive tuberculosis. It is unclear how and whether it can be used together with rifamycins, which are key sterilizing first-line drugs. In this analysis, data were pooled from two studies: the Assessing Pretomanid for Tuberculosis (APT) trial, in which patients with drug-sensitive pulmonary TB received pretomanid, isoniazid, and pyrazinamide plus either rifampin or rifabutin versus standard of care under fed conditions, and the AIDS Clinical Trials Group 5306 (A5306) trial, a phase I study in healthy volunteers receiving pretomanid alone or in combination with rifampin under fasting conditions. In our population pharmacokinetic (PK) model, participants taking rifampin had 44.4 and 59.3% reductions in pretomanid AUC (area under the concentration-time curve) compared to those taking rifabutin or pretomanid alone (due to 80 or 146% faster clearance) in the APT and A5306 trials, respectively. Median maximum concentrations (C_max) in the rifampin and rifabutin arms were 2.14 and 3.35 mg/liter, while median AUC_0-24 values were 30.1 and 59.5 mg·h/liter, respectively. Though pretomanid exposure in APT was significantly reduced with rifampin, AUC_0-24 values were similar to those associated with effective treatment in registrational trials, likely because APT participants were fed with dosing, enhancing pretomanid relative bioavailability and exposures. Pretomanid concentrations with rifabutin were high but in range with prior observations. While pretomanid exposures with rifampin are unlikely to impair efficacy, our data suggest that pretomanid should be taken with food if prescribed with rifampin. (This study has been registered at ClinicalTrials.gov under identifier NCT02256696.).

All nonadherence is equal but is some more equal than others? Tuberculosis in the digital era

Adherence to treatment for tuberculosis (TB) has been a concern for many decades, resulting in the World Health Organization's recommendation of the direct observation of treatment in the 1990s. Recent advances in digital adherence technologies (DATs) have renewed discussion on how to best address nonadherence, as well as offering important information on dose-by-dose adherence patterns and their variability between countries and settings. Previous studies have largely focussed on percentage thresholds to delineate sufficient adherence, but this is misleading and limited, given the complex and dynamic nature of adherence over the treatment course. Instead, we apply a standardised taxonomy - as adopted by the international adherence community - to dose-by-dose medication-taking data, which divides missed doses into 1) late/noninitiation (starting treatment later than expected/not starting), 2) discontinuation (ending treatment early), and 3) suboptimal implementation (intermittent missed doses). Using this taxonomy, we can consider the implications of different forms of nonadherence for intervention and regimen design. For example, can treatment regimens be adapted to increase the "forgiveness" of common patterns of suboptimal implementation to protect against treatment failure and the development of drug resistance? Is it reasonable to treat all missed doses of treatment as equally problematic and equally common when deploying DATs? Can DAT data be used to indicate the patients that need enhanced levels of support during their treatment course? Critically, we pinpoint key areas where knowledge regarding treatment adherence is sparse and impeding scientific progress.

Measuring and reporting treatment adherence: What can we learn by comparing two respiratory conditions?

Medication non-adherence, defined as any deviation from the regimen recommended by their healthcare provider, can increase morbidity, mortality and side effects, while reducing effectiveness. Through studying two respiratory conditions, asthma and tuberculosis (TB), we thoroughly review the current understanding of the measurement and reporting of medication adherence. In this paper, we identify major methodological issues in the standard ways that adherence has been conceptualised, defined and studied in asthma and TB. Between and within the two diseases there are substantial variations in adherence reporting, linked to differences in dosing intervals and treatment duration. Critically, the communicable nature of TB has resulted in dose-by-dose monitoring becoming a recommended treatment standard. Through the lens of these similarities and contrasts, we highlight contemporary shortcomings in the generalised conceptualisation of medication adherence. Furthermore, we outline elements in which knowledge could be directly transferred from one condition to the other, such as the application of large-scale cost-effective monitoring methods in TB to resource-poor settings in asthma. To develop a more robust evidence-based approach, we recommend the use of standard taxonomies detailed in the ABC taxonomy when measuring and discussing adherence. Regimen and intervention development and use should be based on sufficient evidence of the commonality and type of adherence behaviours displayed by patients with the relevant condition. A systematic approach to the measurement and reporting of adherence could improve the value and generalisability of research across all health conditions.

Managing Uncertainties Due to Limited Evidence in Economic Evaluations of Novel Anti-Tuberculosis Regimens: A Systematic Review

BACKGROUND

Limited evidence for the implementation of new health technologies in low- and middle-income countries (LMICs) may lead to uncertainties in economic evaluations and cause the evaluations to produce inaccurate information for decision making. We performed a systematic review of economic evaluations on implementing new short-course regimens (SCR) for drug-sensitive and drug-resistant tuberculosis (TB), to explore how uncertainties due to the limited evidence in the studies were dealt with and to identify useful information for decision making from these studies.

METHODS

We searched in electronic databases PubMed, EMBASE, NHSEED, and CEA registry for economic evaluations addressing the implementation of new anti-TB SCRs in LMICs published until September 2018. We included studies addressing both the cost and outcomes of implementing a new regimen for drug-sensitive and drug-resistant TB with a shorter treatment duration than the currently used regimens. The quality of the included studies was assessed using The Consensus Health Economic Criteria checklist. We extracted information from the included studies on uncertainties and how they were managed. The management of uncertainties was compared with approaches used in early health technology assessments (HTAs), including sensitivity analyses and pragmatic scenario analyses. We extracted information that could be useful for decision making such as cost-effectiveness conclusions, and barriers to implementing the intervention.

RESULTS

Four of the 322 studies found in the search met the eligibility criteria. Three studies were model-based studies that investigated the cost effectiveness of a new first-line SCR. One study was an empirical study investigating the cost effectiveness of new regimens for drug-resistant TB. The model-based studies addressed uncertainties due to limited evidence through various sensitivity analyses as in early HTAs. They performed a deterministic sensitivity analysis and found the main drivers of the cost-effectiveness outcomes, that is, the rate of treatment default and treatment delivery costs. Additionally, two of the model-based studies performed a pragmatic scenario analysis and found a potential barrier to implementing the new first-line SCR, that is, a weak health system with a low TB care utilization rate. The empirical study only performed a few scenario analyses with different regimen prices and volumes of TB care utilization. Therefore, the study could only provide information on the main cost drivers.

CONCLUSION

Using an approach similar to that used in early HTAs, where uncertainties due to the limited evidence are rigorously explored upfront, the economic evaluations could inform not only the decision to implement the intervention but also how to manage risks and implementation barriers.

The association between internal migration and pulmonary tuberculosis in China, 2005-2015: a spatial analysis

BACKGROUND

Internal migration places individuals at high risk of contracting tuberculosis (TB). However, there is a scarcity of national-level spatial analyses regarding the association between TB and internal migration in China. In our research, we aimed to explore the spatial variation in cases of sputum smear-positive pulmonary TB (SS + PTB) in China; and the associations between SS + PTB, internal migration, socioeconomic factors, and demographic factors in the country between 2005 and 2015.

METHODS

Reported cases of SS + PTB were obtained from the national PTB surveillance system database; cases were obtained at the provincial level. Internal migration data were extracted from the national population sampling survey and the census. Spatial autocorrelations were explored using the global Moran's statistic and local indicators of spatial association. The spatial temporal analysis was performed using Kulldorff's scan statistic. Fixed effects regression was used to explore the association between SS + PTB and internal migration.

RESULTS

A total of 4 708 563 SS + PTB cases were reported in China between 2005 and 2015, of which 3 376 011 (71.7%) were male and 1 332 552 (28.3%) were female. There was a trend towards decreasing rates of SS + PTB notifications between 2005 and 2015. The result of global spatial autocorrelation indicated that there were significant spatial correlations between SS + PTB rate and internal migration each year (2005-2015). Spatial clustering of SS + PTB cases was mainly located in central and southern China and overlapped with the clusters of emigration. The proportions of emigrants and immigrants were significantly associated with SS + PTB. Per capita GDP and education level were negatively associated with SS + PTB. The internal migration flow maps indicated that migrants preferred neighboring provinces, with most migrating for work or business.

CONCLUSIONS

This study found a significant spatial autocorrelation between SS + PTB and internal migration. Both emigration and immigration were statistically associated with SS + PTB, and the association with emigration was stronger than that for immigration. Further, we found that SS + PTB clusters overlapped with emigration clusters, and the internal migration flow maps suggested that migrants from SS + PTB clusters may influence the TB epidemic characteristics of neighboring provinces. These findings can help stakeholders to implement effective PTB control strategies for areas at high risk of PTB and those with high rates of internal migrants.

Estimating the impact of a novel drug regimen for treatment of tuberculosis: a modeling analysis of projected patient outcomes and epidemiological considerations

BACKGROUND

Regimens that could treat both rifampin-resistant (RR) and rifampin-susceptible tuberculosis (TB) while shortening the treatment duration have reached late-stage clinical trials. Decisions about whether and how to implement such regimens will require an understanding of their likely clinical impact and how this impact depends on local epidemiology and implementation strategy.

METHODS

A Markov state-transition model of 100,000 representative South African adults with TB was used to simulate implementation of the regimen BPaMZ (bedaquiline, pretomanid, moxifloxacin, and pyrazinamide), either for RR-TB only or universally for all patients. Patient outcomes, including cure rates, time with active TB, and time on treatment, were compared to outcomes under current care. Sensitivity analyses varied the drug-resistance epidemiology, rifampin susceptibility testing practices, and regimen efficacy.

RESULTS

Using BPaMZ exclusively for RR-TB increased the proportion of all RR-TB that was cured by initial treatment from 60 ± 1% to 67 ± 1%. Expanding use of BPaMZ to all patients increased cure of RR-TB to 89 ± 1% and cure of all TB from 87.3 ± 0.1% to 89.5 ± 0.1%, while shortening treatment by 1.9 months/person. In sensitivity analyses, reducing the coverage of rifampin susceptibility testing resulted in lower projected proportions of patients cured under all regimen scenarios (current care, RR-only BPaMZ, and universal BPaMZ), compared to the proportions projected using South Africa's high coverage; however, this reduced coverage resulted in greater expected incremental benefits of universal BPaMZ implementation, both when compared to RR-only BPaMZ implementation and when compared to to current care under the same low rifampin susceptibility testing coverage. In settings with higher RR-TB prevalence, the benefits of BPaMZ were magnified both for RR-specific and universal BPaMZ implementation.

CONCLUSIONS

Novel regimens such as BPaMZ could improve RR-TB outcomes and shorten treatment for all patients, particularly with universal use. Decision-makers weighing early options for implementing such regimens at scale will want to consider the expected impact on patient outcomes and on the burden of treatment in their local context.

High non-compliance rate with anti-tuberculosis treatment: a need to shift facility-based directly observed therapy short course (DOTS) to community mobile outreach team supervision in Saudi Arabia

Background

Tuberculosis (TB) remains a major global public health problem in many developing countries including Kingdom of Saudi Arabia (KSA). Patient compliance with anti-tuberculosis treatment is a determining factor in controlling the spread of TB. This study compares the default rate and the perception of their treatment among TB patients being treated by means of a community mobile outreach approach, with those of patients being treated by means of a facility-based Directly Observed Treatment Short course (DOTS) in the Jeddah region of Saudi Arabia.

Methods

A comparative cross-sectional study of 200 TB patients who presented at the Madain Alfahd Primary Health Care Center (PHCC) Jeddah, between January 2018 and November 2018 was undertaken. In one group, randomly assigned patients were served by mobile outreach teams who administered oral anti-TB treatment under the DOTS regime. In the other group, the patients were treated by means of the traditional facility-based DOTS treatment. A questionnaire measuring patient attitudes and understanding of the disease and their treatment modes was completed by patients at the beginning of their treatment, and again after 3 months. The results were analysed by means of independent and Paired T Tests, along with chi square analysis.

Results

We found that the overall default rate among those patients served by our mobile outreach team was only 3%, compared with a 22% default rate among non-mobile team treated patients (p = < 0.001). A major change in the attitude and understanding scores of patients was noted in both groups after 3 months. A significant difference was also noted in the mean compliance scores (mobile team served =58.43 and facility-based =55.55, p < 0.001) after 3 months of treatment.

Conclusion

Our study indicated that treatment by means of our mobile outreach DOTS can offer an effective strategy for the treatment of TB patients. A reduced patient default rate and a better understanding of the disease and its treatment confirmed a positive impact of mobile outreach teams on these patients. Treating TB patients by means of mobile outreach teams can thus be recommended as a means for the cure and prevention of the further spread of the disease.

Inhaled Antibiotics for Mycobacterial Lung Disease

Mycobacterial lung diseases are an increasing global health concern. Tuberculosis and nontuberculous mycobacteria differ in disease severity, epidemiology, and treatment strategies, but there are also a number of similarities. Pathophysiology and disease progression appear to be relatively similar between these two clinical diagnoses, and as a result these difficult to treat pulmonary infections often require similarly extensive treatment durations of multiple systemic drugs. In an effort to improve treatment outcomes for all mycobacterial lung diseases, a significant body of research has investigated the use of inhaled antibiotics. This review discusses previous research into inhaled development programs, as well as ongoing research of inhaled therapies for both nontuberculous mycobacterial lung disease, and tuberculosis. Due to the similarities between the causative agents, this review will also discuss the potential cross-fertilization of development programs between these similar-yet-different diseases. Finally, we will discuss some of the perceived difficulties in developing a clinically utilized inhaled antibiotic for mycobacterial diseases, and potential arguments in favor of the approach.

Evaluating the impact of social support services on tuberculosis treatment default in Ukraine

Ukraine is among the top 20 highest drug-resistant tuberculosis burden countries in the world. Driving the high drug-resistant tuberculosis rates is an unchecked treatment default rate. This evaluation measures the effect of social support provided to tuberculosis patients at risk of defaulting on treatment during outpatient treatment. Five tuberculosis patient cohorts, served in three oblasts from 2011 and 2012, were constructed from medical records to compare risk factors for default, receipt of social services, and treatment outcome. Regression analyses were used to identify risk factors predictive of treatment default and to estimate the impact of the social support program on treatment default, controlling for risk, disease status, and demographics. In 2012, tuberculosis patients receiving social support in Ukraine reduced their probability of defaulting on continuation treatment by 10 percentage points compared to high-risk patients who did not receive social support in 2012 or 2011. Treatment success rates for the high-risk patients receiving social support were comparable to the low-risk cohorts and significantly improved over the high-risk comparison cohorts. Further research is recommended to quantify the costs and benefits for scaling-up social support services, evaluate social support program fidelity, identify which populations respond best to select services, and what barriers might still exist to achieve better adherence. With that information, tailoring programs to most effectively reach and serve clients in a patient-centered approach may reap substantial rewards for Ukraine.

Health-related quality of life among pulmonary tuberculosis patients in Pakistan

PURPOSE

Health-related quality of life (HRQoL) of pulmonary TB patients has not been assessed in Pakistan. We assessed self-reported HRQoL of pulmonary TB patients in Karachi, Pakistan utilizing the EQ-5D and EQ-VAS prior to, during, and after completion of TB treatment.

METHODS

We enrolled 226 pulmonary TB patients in a longitudinal cohort study. Health-utility scores were estimated by the EQ-5D five dimensions and the EQ-Visual Analogue Scale (VAS) at baseline (month 0) and each monthly follow-up visit until treatment completion at month 6. Repeated-measures ANOVA was used to investigate effect of time into treatment on EQ-5D and EQ-VAS scores.

RESULTS

EQ-5D health utility and EQ-VAS scores increase with treatment progression. For the enrolled TB patients, the mean EQ-5D utility scores more than doubled from 0.43 to 0.88, p < .001, effect size η² = 0.40 from treatment initiation to treatment completion.

CONCLUSION

Perceived HRQoL of TB patients improves with treatment progression. This can inform targeted treatment plans as well as TB policy and funding for high-burden countries.

Evaluation of serum inflammatory biomarkers as predictors of treatment outcome in pulmonary tuberculosis

OBJECTIVE

To evaluate C-reactive protein (CRP), globulin and white blood cell (WBC) count as predictors of treatment outcome in pulmonary tuberculosis (PTB).

METHODS

An observational study of patients with active PTB was conducted at a tertiary centre. All patients had serum CRP, globulin and WBC measured at baseline and at 2 months following commencement of treatment. The outcome of interest was requirement for extension of treatment beyond 6 months.

RESULTS

There were 226 patients included in the study. Serum globulin 45 g/l was the only baseline biomarker evaluated that independently predicted requirement for treatment extension (OR 3.42, 95%CI 1.597.32, P 0.001). An elevated globulin level that failed to normalise at 2 months was also associated with increased requirement for treatment extension (63.9% vs. 5.1%, P 0.001), and had a low negative likelihood ratio (0.07) for exclusion of requirement for treatment extension. On multivariable analysis, an elevated globulin that failed to normalise at 2 months was independently associated with requirement for treatment extension (OR 6.13, 95%CI 2.2316.80, P 0.001).

CONCLUSIONS

Serum globulin independently predicts requirement for treatment extension in PTB and outperforms CRP and WBC as a predictive biomarker. Normalisation of globulin at 2 months following treatment commencement is associated with low risk of requirement for treatment extension.

Monitoring Response to Therapy

Monitoring response to treatment is a key element in the management of infectious diseases, yet controversies still persist on reliable biomarkers for noninvasive response evaluation. Considering the limitations of invasiveness of most diagnostic procedures and the issue of expression heterogeneity of pathology, molecular imaging is better able to assay in vivo biologic processes noninvasively and quantitatively. The usefulness of ¹⁸F-FDG-PET/CT in assessing treatment response in infectious diseases is more promising than for conventional imaging. However, there are currently no clinical criteria or recommended imaging modalities to objectively evaluate the effectiveness of antimicrobial treatment. Therapeutic effectiveness is currently gauged by the patient's subjective clinical response. In this review, we present the current studies for monitoring treatment response, with a focus on Mycobacterium tuberculosis, as it remains a major worldwide cause of morbidity and mortality. The role of molecular imaging in monitoring other infections including spondylodiscitis, infected prosthetic vascular grafts, invasive fungal infections, and a parasitic disease is highlighted. The role of functional imaging in monitoring lipodystrophy associated with highly active antiretroviral therapy for human immunodeficiency virus is considered. We also discuss the key challenges and emerging data in optimizing noninvasive response evaluation.

Risk factors associated with loss to follow-up from tuberculosis treatment in Tajikistan: a case-control study

BACKGROUND

There are very few studies on reasons for loss to follow-up from TB treatment in Central Asia. This study assessed risk factors for LTFU and compared their occurrence with successfully treated (ST) patients in Tajikistan.

METHODS

This study took place in all TB facilities in the 19 districts with at least 5 TB patients registered as loss to follow-up (LTFU) from treatment. With a matched case control design we included all LTFU patients registered in the selected districts in 2011 and 2012 as cases, with ST patients from the same districts being controls. Data were copied from patient records and registers. Conditional logistic regressions were run to analyse associations between collected variables and LTFU as dependent variable.

RESULTS

Three hundred cases were compared to 592 controls. Half of the cases had migrated or moved. In multivariate analysis, risk factors associated with increased LTFU were migration to another country (OR 10.6, 95% CI 6.12-18.4), moving within country (OR 11.0, 95% CI 3.50-34.9), having side effects of treatment (OR 3.67, 95% CI 1.68-8.00) and being previously treated for TB (OR 2.03, 95% CI 1.05-3.93). Medical staff also mentioned patient refusal, stigma and family problems as risk factors.

CONCLUSIONS

LTFU of TB patients in Tajikistan is largely a result of migration, and to a lesser extent associated with side-effects and previous treatment. There is a need to strengthen referral between health facilities within Tajikistan and with neighbouring countries and support patients with side effects and/or previous TB to prevent loss to follow-up from treatment.

MDR-TB treatment as prevention: The projected population-level impact of expanded treatment for multidrug-resistant tuberculosis

Background

In 2013, approximately 480,000 people developed active multidrug-resistant tuberculosis (MDR-TB), while only 97,000 started MDR-TB treatment. We sought to estimate the impact of improving access to MDR-TB diagnosis and treatment, under multiple diagnostic algorithm and treatment regimen scenarios, on ten-year projections of MDR-TB incidence and mortality.

Methods

We constructed a dynamic transmission model of an MDR-TB epidemic in an illustrative East/Southeast Asian setting. Using approximate Bayesian computation, we investigated a wide array of potential epidemic trajectories consistent with current notification data and known TB epidemiology.

Results

Despite an overall projected decline in TB incidence, data-consistent simulations suggested that MDR-TB incidence is likely to rise between 2015 and 2025 under continued 2013 treatment practices, although with considerable uncertainty (median 17% increase, 95% Uncertainty Range [UR] -38% to +137%). But if, by 2017, all identified active TB patients with previously-treated TB could be tested for drug susceptibility, and 85% of those with MDR-TB could initiate MDR-appropriate treatment, then MDR-TB incidence in 2025 could be reduced by 26% (95% UR 4–52%) relative to projections under continued current practice. Also expanding this drug-susceptibility testing and appropriate MDR-TB treatment to treatment-naïve as well as previously-treated TB cases, by 2020, could reduce MDR-TB incidence in 2025 by 29% (95% UR 6–55%) compared to continued current practice. If this diagnosis and treatment of all MDR-TB in known active TB cases by 2020 could be implemented via a novel second-line regimen with similar effectiveness and tolerability as current first-line therapy, a 54% (95% UR 20–74%) reduction in MDR-TB incidence compared to current-practice projections could be achieved by 2025.

Conclusions

Expansion of diagnosis and treatment of MDR-TB, even using current sub-optimal second-line regimens, is expected to significantly decrease MDR-TB incidence at the population level. Focusing MDR diagnostic efforts on previously-treated cases is an efficient first-step approach.

An ontology for factors affecting tuberculosis treatment adherence behavior in sub-Saharan Africa

PURPOSE

Adherence behavior is a complex phenomenon influenced by diverse personal, cultural, and socioeconomic factors that may vary between communities in different regions. Understanding the factors that influence adherence behavior is essential in predicting which individuals and communities are at risk of nonadherence. This is necessary for supporting resource allocation and intervention planning in disease control programs. Currently, there is no known concrete and unambiguous computational representation of factors that influence tuberculosis (TB) treatment adherence behavior that is useful for prediction. This study developed a computer-based conceptual model for capturing and structuring knowledge about the factors that influence TB treatment adherence behavior in sub-Saharan Africa (SSA).

METHODS

An extensive review of existing categorization systems in the literature was used to develop a conceptual model that captured scientific knowledge about TB adherence behavior in SSA. The model was formalized as an ontology using the web ontology language. The ontology was then evaluated for its comprehensiveness and applicability in building predictive models.

CONCLUSION

The outcome of the study is a novel ontology-based approach for curating and structuring scientific knowledge of adherence behavior in patients with TB in SSA. The ontology takes an evidence-based approach by explicitly linking factors to published clinical studies. Factors are structured around five dimensions: factor type, type of effect, regional variation, cross-dependencies between factors, and treatment phase. The ontology is flexible and extendable and provides new insights into the nature of and interrelationship between factors that influence TB adherence.

Tuberculosis

Although the worldwide incidence of tuberculosis has been slowly decreasing, the global disease burden remains substantial (∼9 million cases and ∼1·5 million deaths in 2013), and tuberculosis incidence and drug resistance are rising in some parts of the world such as Africa. The modest gains achieved thus far are threatened by high prevalence of HIV, persisting global poverty, and emergence of highly drug-resistant forms of tuberculosis. Tuberculosis is also a major problem in health-care workers in both low-burden and high-burden settings. Although the ideal preventive agent, an effective vaccine, is still some time away, several new diagnostic technologies have emerged, and two new tuberculosis drugs have been licensed after almost 50 years of no tuberculosis drugs being registered. Efforts towards an effective vaccine have been thwarted by poor understanding of what constitutes protective immunity. Although new interventions and investment in control programmes will enable control, eradication will only be possible through substantial reductions in poverty and overcrowding, political will and stability, and containing co-drivers of tuberculosis, such as HIV, smoking, and diabetes.

Predictors of Default from Treatment for Tuberculosis: a Single Center Case-Control Study in Korea

Default from tuberculosis (TB) treatment could exacerbate the disease and result in the emergence of drug resistance. This study identified the risk factors for default from TB treatment in Korea. This single-center case-control study analyzed 46 default cases and 100 controls. Default was defined as interrupting treatment for 2 or more consecutive months. The reasons for default were mainly incorrect perception or information about TB (41.3%) and experience of adverse events due to TB drugs (41.3%). In univariate analysis, low income (< 2,000 US dollars/month, 88.1% vs. 68.4%, P = 0.015), absence of TB stigma (4.3% vs. 61.3%, P < 0.001), treatment by a non-pulmonologist (74.1% vs. 25.9%, P < 0.001), history of previous treatment (37.0% vs. 19.0%, P = 0.019), former defaulter (15.2% vs. 2.0%, P = 0.005), and combined extrapulmonary TB (54.3% vs. 34.0%, P = 0.020) were significant risk factors for default. In multivariate analysis, the absence of TB stigma (adjusted odd ratio [aOR]: 46.299, 95% confidence interval [CI]: 8.078-265.365, P < 0.001), treatment by a non-pulmonologist (aOR: 14.567, 95% CI: 3.260-65.089, P < 0.001), former defaulters (aOR: 33.226, 95% CI: 2.658-415.309, P = 0.007), and low income (aOR: 5.246, 95% CI: 1.249-22.029, P = 0.024) were independent predictors of default from TB treatment. In conclusion, patients with absence of disease stigma, treated by a non-pulmonologist, who were former defaulters, and with low income should be carefully monitored during TB treatment in Korea to avoid treatment default.

Burden of transmitted multidrug resistance in epidemics of tuberculosis: a transmission modelling analysis

Background

Multidrug-resistant tuberculosis (MDR-TB) can be acquired through de novo mutation during TB treatment or through transmission from other individuals with active MDR-TB. Understanding the balance between these two mechanisms is essential when allocating resources for MDR-TB.

Methods

We constructed a dynamic transmission model of an MDR-TB epidemic, allowing for both treatment-related acquisition and person-to-person transmission of resistance. We used national TB notification data to inform Bayesian estimates of the fraction of each country’s 2013 MDR-TB incidence that resulted from MDR transmission rather than treatment-related MDR acquisition.

Findings

Global estimates of 3·5% MDR-TB prevalence among new TB notifications and 20·5% among retreatment notifications translate into an estimate that resistance transmission rather than acquisition accounts for a median 96% (95% UR: 68–100%) of all incident MDR-TB, and 61% (16–95%) of incident MDR-TB in previously-treated individuals. The estimated percentage of MDR-TB resulting from transmission varied substantially with different countries’ notification data; for example, we estimated this percentage at 48% (30–75%) of MDR-TB in Bangladesh, versus 99% (91–100%) in Uzbekistan. Estimates were most sensitive to estimates of the transmissibility of MDR strains, the probability of acquiring MDR during tuberculosis treatment, and the responsiveness of MDR TB to first-line treatment.

Interpretation

Notifications of MDR prevalence from most high-burden settings are most consistent with the vast majority of incident MDR-TB resulting from transmission rather than new treatment-related acquisition of resistance. Merely improving the treatment of drug-susceptible TB is unlikely to greatly reduce future MDR-TB incidence. Improved diagnosis and treatment of MDR-TB – including new tests and drug regimens – should be highly prioritized.

Risk factors associated with default among tuberculosis patients in Darjeeling district of West Bengal, India

Background:

The treatment outcome “default” under Revised National Tuberculosis Control Program (RNTCP) is a patient who after treatment initiation has interrupted treatment consecutively for more than 2 months.

Aims:

To assess the timing, characteristics and distribution of the reasons for default with relation to some sociodemographic variables among new sputum-positive (NSP) tuberculosis (TB) patients in Darjeeling District, West Bengal.

Settings and Design:

A case-control study was conducted in three tuberculosis units (TUs) of Darjeeling from August’2011 to December’2011 among NSP TB patients enrolled for treatment in the TB register from 1^st Qtr’09 to 2^nd Qtr’10. Patients defaulted from treatment were considered as “cases” and those completed treatment as “controls” (79 cases and 79 controls).

Materials and Methods:

The enrolled cases and controls were interviewed by the health workers using a predesigned structured pro-forma.

Statistical Analysis Used:

Logistic regression analysis, odds ratios (OR), adjusted odds ratios (AOR).

Results:

75% of the default occurred in the intensive phase (IP); 54.24% retrieval action was done within 1 day during IP and 75% within 1 week during continuation phase (CP); cent percent of the documented retrieval actions were undertaken by the contractual TB program staffs. Most commonly cited reasons for default were alcohol consumption (29.11%), adverse effects of drugs (25.32%), and long distance of DOT center (21.52%). In the logistic regression analysis, the factors independently associated were consumption of alcohol, inadequate knowledge about TB, inadequate patient provider interaction, instances of missed doses, adverse reactions of anti-TB drugs, Government Directly Observed Treatment (DOT) provider and smoking.

Conclusions:

Most defaults occurred in the intensive phase; pre-treatment counseling and initial home visit play very important role in this regard. Proper counseling by health care workers in patient provider meeting is needed.

Impact of tuberculosis treatment length and adherence under different transmission intensities

Tuberculosis (TB) is a leading cause of human mortality due to infectious disease. Treatment default is a relevant factor which reduces therapeutic success and increases the risk of resistant TB. In this work we analyze the relation between treatment default and treatment length along with its consequence on the disease spreading. We use a stylized model structure to explore, systematically, the effects of varying treatment duration and compliance. We find that shortening treatment alone may not reduce TB prevalence, especially in regions where transmission intensity is high, indicating the necessity of complementing this action with increased compliance. A family of default functions relating the proportion of defaulters to the treatment length is considered and adjusted to a particular dataset. We find that the epidemiological benefits of shorter treatment regimens are tightly associated with increases in treatment compliance and depend on the epidemiological background.

Patient Characteristics Associated with Tuberculosis Treatment Default: A Cohort Study in a High-Incidence Area of Lima, Peru

Background

Although tuberculosis (TB) is usually curable with antibiotics, poor adherence to medication can lead to increased transmission, drug resistance, and death. Prior research has shown several factors to be associated with poor adherence, but this problem remains a substantial barrier to global TB control. We studied patients in a high-incidence district of Lima, Peru to identify factors associated with premature termination of treatment (treatment default).

Methods

We conducted a prospective cohort study of adult smear-positive TB patients enrolled between January 2010 and December 2011 with no history of TB disease. Descriptive statistics and multivariable logistic regression analyses were performed to determine risk factors associated with treatment default.

Results

Of the 1233 patients studied, 127 (10%) defaulted from treatment. Patients who defaulted were more likely to have used illegal drugs (OR = 4.78, 95% CI: 3.05-7.49), have multidrug-resistant TB (OR = 3.04, 95% CI: 1.58-5.85), not have been tested for HIV (OR = 2.30, 95% CI: 1.50-3.54), drink alcohol at least weekly (OR = 2.22, 95% CI: 1.40-3.52), be underweight (OR = 2.08, 95% CI: 1.21-3.56), or not have completed secondary education (OR = 1.55, 95% CI: 1.03-2.33).

Conclusions

Our study identified several factors associated with defaulting from treatment, suggesting a complex set of causes that might lead to default. Addressing these factors individually would be difficult, but they might help to identify certain high-risk patients for supplemental intervention prior to treatment interruption. Treatment adherence remains a barrier to successful TB care and reducing the frequency of default is important for both the patients’ health and the health of the community.

A practical approach to reporting treatment abandonment in pediatric chronic conditions

Treatment abandonment, the failure to complete therapy that is required for definitive disease control, frequently causes treatment failure for pediatric patients in low- and middle-income countries with chronic conditions, particularly cancer. Other forms of incomplete treatment affecting children in all settings, such as nonadherence and loss to follow-up, are often confused with treatment abandonment. Unclear definitions of incomplete treatment dramatically affect reported outcomes. To facilitate disease-specific and cross-sector analyses, we outline a practical approach to categorize forms of incomplete treatment, present distinct semantic categories with case examples and provide an algorithm that could be tailored to disease- and context-specific needs.

Interpreting measures of tuberculosis transmission: a case study on the Portuguese population

Background

Tuberculosis remains a high burden for Human society despite considerable investments in its control. Unique features in the history of infection and transmission dynamics of tuberculosis pose serious limitations on the direct interpretation of surveillance data and call for models that incorporate latent processes and simulate specific interventions.

Methods

A transmission model was adjusted to the dataset of active tuberculosis cases reported in Portugal between 2002 and 2009. We estimated key transmission parameters from the data (i.e. time to diagnosis, treatment length, default proportion, proportion of pulmonary TB cases). Using the adjusted model to the Portuguese case, we estimated the total burden of tuberculosis in Portugal. We further performed sensitivity analysis to heterogeneities in susceptibility to infection and exposure intensity.

Results

We calculated a mean time to diagnose of 2.81 months and treatment length of 8.80 months in Portugal. The proportion defaulting treatment was calculated as 0.04 and the proportion of pulmonary cases as 0.75. Using these values, we estimated a TB burden of 1.6 million infected persons, corresponding to more than 15% of the Portuguese population. We further described the sensitivity of these estimates to heterogeneity.

Conclusions

We showed that the model reproduces well the observed dynamics of the Portuguese data, thus demonstrating its adequacy for devising control strategies for TB and predicting the effects of interventions.

Population-level impact of shorter-course regimens for tuberculosis: a model-based analysis

Despite current control efforts, global tuberculosis (TB) incidence is decreasing slowly. New regimens that can shorten treatment hold promise for improving treatment completion and success, but their impact on population-level transmission remains unclear. Earlier models projected that a four-month regimen could reduce TB incidence by 10% but assumed that an entire course of therapy must be completed to derive any benefit. We constructed a dynamic transmission model of TB disease calibrated to global estimates of incidence, prevalence, mortality, and treatment success. To account for the efficacy of partial treatment, we used data from clinical trials of early short-course regimens to estimate relapse rates among TB patients who completed one-third, one-half, two-thirds, and all of their first-line treatment regimens. We projected population-level incidence and mortality over 10 years, comparing standard six-month therapy to hypothetical shorter-course regimens with equivalent treatment success but fewer defaults. The impact of hypothetical four-month regimens on TB incidence after 10 years was smaller than estimated in previous modeling analyses (1.9% [95% uncertainty range 0.6-3.1%] vs. 10%). Impact on TB mortality was larger (3.5% at 10 years) but still modest. Transmission impact was most sensitive to the proportion of patients completing therapy: four-month therapy led to greater incidence reductions in settings where 25% of patients leave care ("default") over six months. Our findings remained robust under one-way variation of model parameters. These findings suggest that novel regimens that shorten treatment duration may have only a modest effect on TB transmission except in settings of very low treatment completion.

Cost-effectiveness of novel first-line treatment regimens for tuberculosis

OBJECTIVE

To evaluate the cost-effectiveness of novel first-line treatment regimens for tuberculosis (TB).

DESIGN

Using decision analysis, we projected the costs and effectiveness, from the health care perspective, of treating a patient cohort in the public sector for active TB without known or suspected resistance to first-line drugs. We compared standard (6-month) treatment to hypothetical regimens of equal efficacy, higher cost and shorter duration.

RESULTS

For every 100 TB patients treated, replacing standard treatment with shorter-course regimens would avert an estimated 2-4 failures/relapses, 0.2-0.4 deaths and 8-14 disability-adjusted life years (DALYs), or 6-11% of all DALYs suffered. We identified three primary determinants of cost-effectiveness: drug price, continuation phase treatment delivery costs and deaths averted through fewer relapses. In a high treatment cost scenario (similar to Brazil), averted delivery costs outweighed higher drug costs, making novel regimens cost-saving. In a low treatment cost scenario (similar to the Philippines), a 4-month regimen with a drug price of $1/day cost $66 per patient, or $840 per DALY averted, and became cost-saving if the drug price dropped below $0.37/day.

CONCLUSION

Although they avert a small proportion of total DALYs, novel, shorter-course first-line regimens for TB are likely to be cost-effective or cost-saving in most settings.

Modeling the impact of early therapy for latent tuberculosis patients and its optimal control analysis

Effective tuberculosis (TB) control depends on case findings to discover infectious cases, investigation of contacts of those with TB, as well as appropriate treatment. Adherence and successful completion of the treatment are equally important. Unfortunately, due to a number of personal, psychosocial, economic, medical, and health service factors, a significant number of TB patients become irregular and default from treatment. In this paper, a mathematical model is developed to assess the impact of early therapy for latent TB and non-adherence on controlling TB transmission dynamics. Equilibrium states of the model are determined and their local stability is examined. With the aid of the center manifold theory, it is established that the model undergoes a backward bifurcation. Qualitative mathematical analysis of the model suggests that a high level of latent tuberculosis case findings, coupled with a decrease of defaulting rate, may be effective in controlling TB transmission dynamics in the community. Population-level effects of organized campaigns to improve early therapy and to guarantee successful completion of each treatment are evaluated through numerical simulations and presented in support of the analytical results.

Risk factors and timing of default from treatment for non-multidrug-resistant tuberculosis in Moldova

SETTING

The Republic of Moldova, in Eastern Europe, has among the highest reported nationwide proportions of tuberculosis (TB) patients with multidrug-resistant tuberculosis (MDR-TB) worldwide. Default has been associated with increased mortality and amplification of drug resistance, and may contribute to the high MDR-TB rates in Moldova.

OBJECTIVE

To assess risk factors and timing of default from treatment for non-MDR-TB from 2007 to 2010.

DESIGN

A retrospective analysis of routine surveillance data on all non-MDR-TB patients reported.

RESULTS

A total of 14.7% of non-MDR-TB patients defaulted from treatment during the study period. Independent risk factors for default included sociodemographic factors, such as homelessness, living alone, less formal education and spending substantial time outside Moldova in the year prior to diagnosis; and health-related factors such as human immunodeficiency virus co-infection, greater lung pathology and increasing TB drug resistance. Anti-tuberculosis treatment is usually initiated within an institutional setting in Moldova, and the default risk was highest in the month following the phase of hospitalized treatment (among civilians) and after leaving prison (among those diagnosed while incarcerated).

CONCLUSIONS

Targeted interventions to increase treatment adherence for patients at highest risk of default, and improving the continuity of care for patients transitioning from institutional to community care may substantially reduce risk of default.

Psychiatric morbidity and other factors affecting treatment adherence in pulmonary tuberculosis patients

As the overall prevalence of TB remains high among certain population groups, there is growing awareness of psychiatric comorbidity, especially depression and its role in the outcome of the disease. The paper attempts a holistic approach to the effects of psychiatric comorbidity to the natural history of tuberculosis. In order to investigate factors associated with medication nonadherence among patients suffering from tuberculosis, with emphasis on psychopathology as a major barrier to treatment adherence, we performed a systematic review of the literature on epidemiological data and past medical reviews from an historical perspective, followed by theoretical considerations upon the relationship between psychiatric disorders and tuberculosis. Studies reporting high prevalence rates of psychiatric comorbidity, especially depression, as well as specific psychological reactions and disease perceptions and reviews indicating psychiatric complications as adverse effects of anti-TB medication were included. In sum, data concerning factors affecting medication nonadherence among TB patients suggested that better management of comorbid conditions, especially depression, could improve the adherence rates, serving as a framework for the effective control of tuberculosis, but further studies are necessary to identify the optimal way to address such issues among these patients.

Tuberculosis treatment default in a large tertiary care hospital in urban Nigeria: prevalence, trend, timing and predictors

OBJECTIVES

Few studies have investigated tuberculosis treatment default in tertiary care settings. We aimed to determine the prevalence, trend, timing and predictors of defaulting from tuberculosis treatment in a Nigerian tertiary hospital.

METHODS

Data entered from 2006 to 2010 in the Federal Medical Centre, Abakaliki, tuberculosis treatment register were sorted into six treatment outcomes. Five outcomes were combined into one variable called 'non-defaulters' and were compared with "defaulters". The statistical analysis was conducted using SPSS.

RESULTS

Of 671 tuberculosis patients, 192 (28.6%) defaulted. Of these, 126 (66%) were ≥30 years old, and 115 (60%) had pulmonary tuberculosis. Furthermore, 106 (55%) were males, and 125 (65%) lived in a rural area. The annual proportion of defaulters dropped from 34.8% to 20.6%, but the decreasing trend was not statistically significant (P=0.132 for trend). Of the defaulters, 148 (77.1%) defaulted during their intensive phase of treatment. The median default time was 7 (IQR 5-8) weeks. The independent predictors of treatment default were older age (aOR 1.5), rural residence (aOR 2.3), and HIV seropositivity (aOR, 2.8).

CONCLUSION

TB treatment default is high and must be reduced. This may be achieved through improved rural DOT, further patient education, and enhanced coordination of TB/HIV care.

Research questions and priorities for tuberculosis: a survey of published systematic reviews and meta-analyses

BACKGROUND

Systematic reviews are increasingly informing policies in tuberculosis (TB) care and control. They may also be a source of questions for future research. As part of the process of developing the International Roadmap for TB Research, we did a systematic review of published systematic reviews on TB, to identify research priorities that are most frequently suggested in reviews.

METHODOLOGY/PRINCIPAL FINDINGS

We searched EMBASE, MEDLINE, Web of Science, and the Cochrane Library for systematic reviews and meta-analyses on any aspect of TB published between 2005 and 2010. One reviewer extracted data and a second reviewer independently extracted data from a random subset of included studies. In total, 137 systematic reviews, with 141 research questions, were included in this review. We used the UK Health Research Classification System (HRCS) to help us classify the research questions and priorities. The three most common research topics were in the area of detection, screening and diagnosis of TB (32.6%), development and evaluation of treatments and therapeutic interventions (23.4%), and TB aetiology and risk factors (19.9%). The research priorities determined were mainly focused on the discovery and evaluation of bacteriological TB tests and drug-resistant TB tests and immunological tests. Other important topics of future research were genetic susceptibility linked to TB and disease determinants attributed to HIV/TB. Evaluation of drug treatments for TB, drug-resistant TB and HIV/TB were also frequently proposed research topics.

CONCLUSIONS

Systematic reviews are a good source of key research priorities. Findings from our survey have informed the development of the International Roadmap for TB Research by the TB Research Movement.

Strategies to Promote Adherence to Treatment by Pulmonary Tuberculosis Patients: A systematic review

BACKGROUND

Successful tuberculosis control depends upon effective treatment of patients which requires adherence throughout the full course of medical treatment. Poor adherence to treatment is a major obstacle in the global fight against tuberculosis. Therefore, interventions that promote adherence to the tuberculosis treatment regimen should be implemented.

OBJECTIVE

To review and synthesise the best available research evidence that investigates the effectiveness of strategies to promote adherence to treatment by patients with pulmonary tuberculosis.

INCLUSION CRITERIA

This review considered all studies that included adults aged ≥ 15 years diagnosed with smear positive and smear negative pulmonary tuberculosis (regardless of HIV infection) in community settings who had never received anti-tuberculosis drugs, or had taken them for less than one month.Intervention included strategies to promote adherence to tuberculosis treatment by patients with pulmonary tuberculosis.Outcomes included measures for treatment completion rate, cure rate, and success rate.The review primarily considered any randomised controlled trials that explored different strategies to promote adherence to tuberculosis treatment of patients with pulmonary tuberculosis but also included quasi-experimental studies.

SEARCH STRATEGY

The search sought to find published and unpublished studies. The time period of the search covered articles published from 1990 to 2010 in English and Thai language. The database searches included: CINAHL, EMBASE, Cochrane Library, PubMed, Science Direct, Current Content Connect, Thai Nursing Research Database, Thai thesis database, Digital Library of Thailand Research Fund, Research of National Research Council of Thailand, and Database of Office of Higher Education Commission. Studies were additionally identified from reference lists of all studies retrieved.

METHODOLOGICAL QUALITY

Studies selected for retrieval were assessed by two independent reviewers for methodological quality using a standardised critical appraisal tool from the Joanna Briggs Institute.

DATA COLLECTION

Data extraction was performed using a standardised data extraction form from the Joanna Briggs Institute.

DATA SYNTHESIS

The quantitative study results were pooled in statistical meta-analysis using the Review Manager software (RevMan 5.0) and summarised in narrative form where statistical pooling was not appropriate or possible.

RESULTS

This systematic review included ten randomised controlled trials and eight quasi-experimental studies that report on the effectiveness of a number of specific interventions to improve adherence to tuberculosis treatment among newly diagnosed pulmonary tuberculosis patients. These interventions included Directly Observed Treatment coupled with alternative patient supervision options, case management with Directly Observed Treatment, Short-course, the intensive triad-model program, and an intervention package consisting of improving patients' counselling and communication, decentralisation of treatment, patient choice of Directly Observed Treatment supporter, and reinforcement of supervision activities.

CONCLUSION

The interventions that had the best outcomes for treatment adherence among newly diagnosed pulmonary tuberculosis patients were Directly Observed Treatment and Directly Observed Treatment, Short-course combined with case management, improving counselling and communication and decentralisation of treatment. These interventions should be implemented by health care providers and tailored to local contexts and circumstances, where appropriate.It would be beneficial to shift the treatment of all pulmonary tuberculosis patients to facilities within the primary health care structure. Directly Observed Treatment coupled with alternative patient supervision options, formalised educational programs and a tuberculosis case management team should be used to improve adherence to tuberculosis treatment among newly diagnosed pulmonary tuberculosis patients.Our review shows the need for further large-scale on adherence to treatment by newly diagnosed pulmonary tuberculosis patients. Factors that determine the usefulness of Directly Observed Treatment in various settings require further study. Further strategies, especially those that are feasible in developing countries or countries with limited resources, should be evaluated in randomised controlled trials before being introduced into routine practice.

Risk factors for default from tuberculosis treatment in HIV-infected individuals in the state of Pernambuco, Brazil: a prospective cohort study

BACKGROUND

Concomitant treatment of Human Immunodeficiency Virus (HIV) infection and tuberculosis (TB) presents a series of challenges for treatment compliance for both providers and patients. We carried out this study to identify risk factors for default from TB treatment in people living with HIV.

METHODS

We conducted a cohort study to monitor HIV/TB co-infected subjects in Pernambuco, Brazil, on a monthly basis, until completion or default of treatment for TB. Logistic regression was used to calculate crude and adjusted odds ratios, 95% confidence intervals and P-values.

RESULTS

From a cohort of 2310 HIV subjects, 390 individuals (16.9%) who had started treatment after a diagnosis of TB were selected, and data on 273 individuals who completed or defaulted on treatment for TB were analyzed. The default rate was 21.7% and the following risk factors were identified: male gender, smoking and CD4 T-cell count less than 200 cells/mm3. Age over 29 years, complete or incomplete secondary or university education and the use of highly active antiretroviral therapy (HAART) were identified as protective factors for the outcome.

CONCLUSION

The results point to the need for more specific actions, aiming to reduce the default from TB treatment in males, younger adults with low education, smokers and people with CD4 T-cell counts < 200 cells/mm3. Default was less likely to occur in patients under HAART, reinforcing the strategy of early initiation of HAART in individuals with TB.

A woman's lived experience with directly observed therapy for tuberculosis-a case study

This is a case study to investigate the lived experience of tuberculosis (TB) treatment for a Hispanic female. The theme was accumulating aggravation. Her daily life was interrupted with appointments and negative side effects. She had to wear a mask that made her feel isolated. She felt ignored by her doctors. Although she experienced the opposite feeling of being overly observed, the informant began to feel like she was always being watched. The participant described herself as paranoid due to the threat of imprisonment for nonadherence. The accumulating aggravation made the directly observed therapy short-course (DOTS) experience a difficulty and stressful experience.

Incidence, time and determinants of tuberculosis treatment default in Yaounde, Cameroon: a retrospective hospital register-based cohort study

Objectives High rates of antituberculosis treatment discontinuation have been reported in some areas of Africa. The aim of this study was to determine the rate, time to and determinants of antituberculosis treatment default in Yaounde. Design This was a retrospective cohort study based on hospital registers. Tuberculosis treatment default or antituberculosis treatment discontinuation was defined as any interruption of treatment for at least 2 months following treatment initiation. Sociodemographic and clinical predictors of treatment discontinuation were investigated with the use of Cox regressions models. Setting This study was carried out in the tuberculosis diagnosis and treatment centre at Yaounde Jamot Hospital, which serves as a referral centre for tuberculosis and respiratory diseases for the capital city of Cameroon (Yaounde) and surrounding areas. Participants All (1688) patients started on antituberculosis treatment at the centre between January and December 2009 were enrolled. Outcome measures were antituberculosis treatment default and time to treatment default. Results Of the 1688 included patients, 337 (20%) defaulted from treatment, 86 (5.1%) died, treatment failed in 6 (0.4%) and 104 (6.2%) were transferred. Therefore, treatment was successfully completed in 1154 (68.4%) patients. Median duration to treatment discontinuation was 90 days (IQR 30-150), and 62% of treatment discontinuation occurred during the continuation phase. Hospitalisation during the intensive phase (adjusted HR 0.69; 95% CI 0.54 to 0.89) and non-consenting for HIV screening (1.65; 1.24 to 2.21) were the main determinants of defaulting from treatment in multivariable analysis. Conclusions The default incidence rate is relatively high in this centre and treatment discontinuation occurs frequently during the continuation phase of treatment. Action is needed to improve adherence to treatment when received on an ambulatory basis, to clarify the association between HIV testing and antituberculosis treatment default, and to identify other potential determinants of treatment discontinuation in this setting.

Early bactericidal activity and pharmacokinetics of PA-824 in smear-positive tuberculosis patients

PA-824 is a novel nitroimidazo-oxazine being evaluated for its potential to improve tuberculosis (TB) therapy. This randomized study evaluated safety, tolerability, pharmacokinetics, and extended early bactericidal activity of PA-824 in drug-sensitive, sputum smear-positive, adult pulmonary tuberculosis patients. Fifteen patients per cohort received 1 of 4 doses of oral PA-824: 200, 600, 1,000, or 1,200 mg per day for 14 days. Eight subjects received once daily standard antituberculosis treatment as positive control. The primary efficacy endpoint was the mean rate of change in log CFU of Mycobacterium tuberculosis in sputum incubated on agar plates from serial overnight sputum collections, expressed as log10 CFU/day/ml (+/-standard deviation [SD]). The drug demonstrated increases that were dose linear but less than dose proportional in serum concentrations in doses from 200 to 1,000 mg daily. Dosing of 1,200 mg gave no additional exposure compared to 1,000 mg daily. The mean daily CFU fall under standard treatment was 0.148 (+/-0.055), consistent with that found in previous studies. The mean daily fall under PA-824 was 0.098 (+/-0.072) and was equivalent for all four dosages. PA-824 appeared safe and well tolerated; the incidence of adverse events potentially related to PA-824 appeared dose related. We conclude that PA-824 demonstrated bactericidal activity over the dose range of 200 to 1,200 mg daily over 14 days. Because maximum efficacy was unexpectedly achieved at the lowest dosage tested, the activity of lower dosages should now be explored.

TB treatment initiation and adherence in a South African community influenced more by perceptions than by knowledge of tuberculosis

Background

Tuberculosis (TB) is a global health concern. Inadequate case finding and case holding has been cited as major barrier to the control of TB. The TB literature is written almost entirely from a biomedical perspective, while recent studies show that it is imperative to understand lay perception to determine why people seek treatment and may stop taking treatment. The Eastern Cape is known as a province with high TB incidence, prevalence and with one of the worst cure rates of South Africa. Its inhabitants can be considered lay experts when it comes to TB. Therefore, we investigated knowledge, perceptions of (access to) TB treatment and adherence to treatment among an Eastern Cape population.

Methods

An area-stratified sampling design was applied. A total of 1020 households were selected randomly in proportion to the total number of households in each neighbourhood.

Results

TB knowledge can be considered fairly good among this community. Respondents' perceptions suggest that stigma may influence TB patients' decision in health seeking behavior and adherence to TB treatment. A full 95% of those interviewed believe people with TB tend to hide their TB status out of fear of what others may say. Regression analyses revealed that in this population young and old, men and women and the lower and higher educated share the same attitudes and perceptions. Our findings are therefore likely to reflect the actual situation of TB patients in this population.

Conclusions

The lay experts' perceptions suggests that stigma appears to effect case holding and case finding. Future interventions should be directed at improving attitudes and perceptions to potentially reduce stigma. This requires a patient-centered approach to empower TB patients and active involvement in the development and implementation of stigma reduction programs.

Risk factors for treatment default among re-treatment tuberculosis patients in India, 2006

Setting

Under India's Revised National Tuberculosis Control Programme (RNTCP), >15% of previously-treated patients in the reported 2006 patient cohort defaulted from anti-tuberculosis treatment.

Objective

To assess the timing, characteristics, and risk factors for default amongst re-treatment TB patients.

Methodology

For this case-control study, in 90 randomly-selected programme units treatment records were abstracted from all 2006 defaulters from the RNTCP re-treatment regimen (cases), with one consecutively-selected non-defaulter per case. Patients who interrupted anti-tuberculosis treatment for >2 months were classified as defaulters.

Results

1,141 defaulters and 1,189 non-defaulters were included. The median duration of treatment prior to default was 81 days (25%–75% interquartile range 44–117 days) and documented retrieval efforts after treatment interruption were inadequate. Defaulters were more likely to have been male (adjusted odds ratio [aOR] 1.4, 95% confidence interval [CI] 1.2–1.7), have previously defaulted anti-tuberculosis treatment (aOR 1.3 95%CI 1.1–1.6], have previous treatment from non-RNTCP providers (AOR 1.3, 95%CI 1.0–1.6], or have public health facility-based treatment observation (aOR 1.3, 95%CI 1.1–1.6).

Conclusions

Amongst the large number of re-treatment patients in India, default occurs early and often. Improved pre-treatment counseling and community-based treatment provision may reduce default rates. Efforts to retrieve treatment interrupters prior to default require strengthening.

Latent tuberculosis infection in children: a call for revised treatment guidelines

BACKGROUND

Guidelines for latent tuberculosis infection do not consider drug-resistance patterns when recommending treatment for immigrant children.

OBJECTIVES

The purpose of this research was to decide at what rate of isoniazid resistance a different regimen other than isoniazid for 9 months should be considered.

METHODS

We constructed a decision tree by using published data. We studied 3 regimens considered to be effective for susceptible organisms: (1) isoniazid for 9 months, (2) rifampin for 6 months, and (3) isoniazid for 9 months plus rifampin for 6 months. In addition, we evaluated a regimen of isoniazid and rifampin for 3 months. Our base case was a 2-year-old child from Russia with a tuberculin skin test reaction of 12 mm. We assumed a societal perspective and expressed results as cost and cost per case of tuberculosis prevented. We conducted sensitivity analyses to test the stability of our model.

RESULTS

In our baseline analysis, rifampin was the least costly treatment regimen for any child arriving from an area with an isoniazid-resistance rate of >/=11%. Treatment with isoniazid plus rifampin was the most effective but would cost more than $1 million per reactivation case prevented. Isoniazid would become the least costly regimen if any of the following thresholds were met: rifampin resistance given isoniazid resistance of more than 82%; rifampin resistance given no isoniazid resistance of >9%; cost of rifampin more than $47/month; effectiveness of rifampin lower than 63%; effectiveness of isoniazid higher than 74%; and cost of pulmonary tuberculosis less than $7661. Isoniazid and rifampin for 3 months was the least costly for all cases from areas with isoniazid resistance of <80% as long as the regimen's effectiveness was >50% for susceptible bacteria. However, this assumption remains to be proven.

CONCLUSION

Because of the high prevalence of isoniazid resistance, rifampin should be considered for children with latent tuberculosis infection originating from countries with >11% isoniazid resistance.