Adherence and Associated Factors of Treatment Regimen in Drug-Susceptible Tuberculosis Patients

Development and validation of a predictive scoring model for risk stratification of tuberculosis treatment interruption

BACKGROUND

Tuberculosis (TB) treatment interruption poses risks of antimicrobial resistance, potentially leading to treatment failure and mortality. Addressing the risk of early treatment interruption is crucial in tuberculosis care and management to improve treatment outcomes and curb disease transmission.

OBJECTIVES

This study aimed to identify risk factors of TB treatment interruption and construct a predictive scoring model that enables objective risk stratification for better prediction of treatment interruption.

METHODS

A multicentre retrospective cohort study was conducted at public health clinics in Sarawak, Malaysia over 11 months from March 2022 to January 2023, involving adult patients aged ≥18 years with drug-susceptible TB diagnosed between 2018 and 2021. Cumulative missed doses or discontinuation of TB medications for ≥2 weeks, either consecutive or non-consecutive, was considered as treatment interruption. The model was developed and internally validated using the split-sample method. Multiple logistic regression analysed 18 pre-defined variables to identify the predictors of TB treatment interruption. The Hosmer-Lemeshow test and area under the receiver operating characteristic curve (AUC) were employed to evaluate model performance.

RESULTS

Of 2953 cases, two-thirds (1969) were assigned to the derivation cohort, and one-third (984) formed the validation cohort. Positive predictors included smoking, previously treated cases, and adverse drug reactions, while concurrent diabetes was protective. Based on the validation dataset, the model demonstrated good calibration (P = 0.143) with acceptable discriminative ability (AUC = 0.775). A cutoff score of 2.5 out of 11 achieved a sensitivity of 81 % and a specificity of 64.4 %. Risk stratification into low (0-2), medium (3-5), and high-risk (≥6) categories showed ascending interruption rates of 5.3 %, 18.1 %, and 41.3 %, respectively (P < 0.001).

CONCLUSION

The predictive scoring model aids in risk assessment for TB treatment interruption, enabling focused monitoring and personalized intervention plans for higher-risk groups in the early treatment phase.

Effect of Metformin on Plasma Exposure of Rifampicin, Isoniazid, and Pyrazinamide in Patients on Treatment for Pulmonary Tuberculosis

BACKGROUND

To evaluate the effect of metformin on the plasma levels of rifampicin, isoniazid, and pyrazinamide in patients with drug-sensitive pulmonary tuberculosis being treated with first-line antituberculosis treatment (ATT) and to assess the influence of gene polymorphisms on the metabolic pathway of metformin and plasma levels of antitubercular drugs.

METHODS

Nondiabetic adults aged 18-60 years with pulmonary tuberculosis were randomized to either the standard ATT (ATT group) or ATT plus metformin (METRIF group) groups in a phase IIB clinical trial. An intensive pharmacokinetic study with blood collection at 0 hour (predosing), followed by 1, 2, 4, 6, 8, and 12 hours after dosing was conducted during the first month of treatment in a subset of 60 study participants after a minimum of 14 doses. Plasma concentrations of rifampicin, isoniazid, pyrazinamide, and metformin were measured by high-performance liquid chromatography using validated methods, and pharmacokinetic parameters and OCT1 and MATE1 gene polymorphisms were compared between the groups.

RESULTS

Significant increases in the clearance of rifampicin, isoniazid, and pyrazinamide were observed in patients in the METRIF group (n = 29) compared with those in the ATT group (n = 31). The AA genotypes of the single-nucleotide polymorphism of rs2289669 ( MATE1 ) in the METRIF group showed a significantly decreased area under the concentration-time curve to the last observation point and increased clearance of rifampicin.

CONCLUSIONS

Metformin altered rifampicin and isoniazid plasma concentrations in patients receiving antituberculosis treatment for pulmonary tuberculosis with little effect on sputum conversion at the end of treatment. Studies with larger sample sizes are needed to understand host drug-drug interactions.

Characteristics, predictors and consequences of tuberculosis treatment interruption: A multicentre retrospective cohort study

OBJECTIVES

Treatment interruption is associated with poor tuberculosis (TB) treatment outcomes and increased drug resistance. To address the issue, we aimed to investigate the characteristics, predictors and consequences of treatment interruption.

METHODS

We conducted a retrospective cohort study by retrieving 4 years (2018-2021) of TB patients' records at 10 public health clinics in Sarawak, Malaysia. Adult patients (≥18 years) with drug-susceptible TB were selected. Treatment interruption was defined as ≥2 weeks of cumulative interruption during treatment. The Chi-square test, Mann-Whitney U test, Kaplan-Meier and Cox proportional hazards regression were used to analyse the data, with p < 0.05 being considered statistically significant.

RESULTS

Out of 2953 eligible patients, 475 (16.1%) experienced TB treatment interruption. Interruptions were most frequent during the intensive phase (46.9%, n = 223), with the greatest risk within the first 4 weeks of treatment. The median time to interruption was 2 weeks in the intensive phase and the cumulative interruption probability at the end of the intensive phase was 12.9%. Notably, treatment interruption occurred during both intensive and continuation phases for 144 patients (30.3%), while the remaining 108 (22.7%) experienced interruptions only during the continuation phase with a median time to interruption of 16 weeks. Three predictors were identified to increase the risk of treatment interruption: adverse drug reaction (aHR = 8.53, 95% Cl: 6.73-10.82), smoking (aHR = 2.67, 95% Cl: 2.03-3.53) and illicit drug use (aHR = 1.88, 95% Cl: 1.03-3.45). Conversely, underlying diabetes was associated with a reduced likelihood of treatment interruption (aHR = 0.72, 95% Cl: 0.58-0.90). Treatment interruption led to significant differences in treatment restarts (62.3% vs. 0.7%), changes in medications (47.8% vs. 4.9%), prolonged treatment duration (247 days [IQR = 105] vs. 194 days [IQR = 44.3]) and lower successful outcomes (86.5% vs. 99.9%).

CONCLUSION

Understanding the temporal characteristics, predictors and negative consequences of treatment interruption can guide the development of time-relevant approaches to mitigate the problem.

Predictors, mortality, and health outcomes of intensive phase non-adherence to a regimen in patients with drug-susceptible tuberculosis: a nationwide linkage database

OBJECTIVES

The clinical importance of adhering to the regimen in tuberculosis patients has been widely investigated, but most studies were conducted in controlled settings and in limited populations. We aimed to measure the level of real-world adherence during intensive phase and investigate the predictors and the risk of mortality and health outcomes of intensive phase non-adherence in tuberculosis patients.

STUDY DESIGN

We conducted a nationwide cohort study by linking the Korean National Tuberculosis Surveillance System and the National Health Information Database.

METHODS

We included all incident drug-susceptible tuberculosis patients who initiated the regimens recommended by the World Health Organization from 2013 to 2018. Adherence was measured using the proportion of days covered (poor [<50%], moderate [50%-79%], and high [≥80%]). We used logistic regression model to assess predictors and the Cox proportional hazard model to evaluate the risk of mortality and health outcomes with intensive phase non-adherence.

RESULTS

Of 46,818 patients, there were 8% and 11% with poor and moderate adherent groups, respectively. Age ≥45 years, insulin use, and history of renal failure were predictors of non-adherence. Compared with high adherent group, poor and moderate adherent groups were associated with a substantial risk of mortality (poor: hazard ratio, 2.14 [95% confidence interval, 1.95-2.34]; moderate: 1.76 [1.62-1.92]). Similar trends were observed for health outcomes. Stratified analyses showed a higher risk of mortality in patients with medical aid, low income, and history of renal failure, systematic corticosteroids, and immunomodulators.

CONCLUSIONS

Non-adherence during intensive phase increased mortality risk by twofold, underscoring targeted intervention for high-risk population, including advanced diabetes, and immunocompromised patients.

Prediction Models for Adverse Drug Reactions During Tuberculosis Treatment in Brazil

BACKGROUND

Tuberculosis (TB) treatment-related adverse drug reactions (TB-ADRs) can negatively affect adherence and treatment success rates.

METHODS

We developed prediction models for TB-ADRs, considering participants with drug-susceptible pulmonary TB who initiated standard TB therapy. TB-ADRs were determined by the physician attending the participant, assessing causality to TB drugs, the affected organ system, and grade. Potential baseline predictors of TB-ADR included concomitant medication (CM) use, human immunodeficiency virus (HIV) status, glycated hemoglobin (HbA1c), age, body mass index (BMI), sex, substance use, and TB drug metabolism variables (NAT2 acetylator profiles). The models were developed through bootstrapped backward selection. Cox regression was used to evaluate TB-ADR risk.

RESULTS

There were 156 TB-ADRs among 102 of the 945 (11%) participants included. Most TB-ADRs were hepatic (n = 82 [53%]), of moderate severity (grade 2; n = 121 [78%]), and occurred in NAT2 slow acetylators (n = 62 [61%]). The main prediction model included CM use, HbA1c, alcohol use, HIV seropositivity, BMI, and age, with robust performance (c-statistic = 0.79 [95% confidence interval {CI}, .74-.83) and fit (optimism-corrected slope and intercept of -0.09 and 0.94, respectively). An alternative model replacing BMI with NAT2 had similar performance. HIV seropositivity (hazard ratio [HR], 2.68 [95% CI, 1.75-4.09]) and CM use (HR, 5.26 [95% CI, 2.63-10.52]) increased TB-ADR risk.

CONCLUSIONS

The models, with clinical variables and with NAT2, were highly predictive of TB-ADRs.

Effect of calcium-channel blockers on the risk of active tuberculosis and mortality: systematic review and meta-analysis

Introduction: Recent studies suggest that calcium channel blockers (CCBs) could reduce the risk of active tuberculosis and improve clinical outcomes. We aimed to synthesize the evidence regarding the effect of CCBs on the risk of developing active tuberculosis and mortality. Methods: We systematically searched for observational studies and clinical trials published in six databases until 31 August 2023, following a PECO/PICO strategy. Results: We included eight observational studies, 4,020,830 patients, among whom 241,761 had diabetes mellitus and 30,397 had active tuberculosis. According to our results, CCBs reduce the risk of developing active tuberculosis by 29% (RR 0.71; 95% CI 0.67-0.75) in patients with and without diabetes mellitus. However, CCBs do not show any benefit in terms of tuberculosis-related mortality (RR 1.00; 95% CI 0.98-1.02). For both outcomes, no statistical heterogeneity was found (I2 = 0, p > 0.10). This protective effect of CCBs on the risk of active tuberculosis remained independent of the type of patient (with diabetes mellitus vs. general population) or the class of CCB administered (DHP-CCB vs. non-DHP-CCB) (test for subgroup differences I2 = 0, p > 0.10). However, this beneficial effect was more significant among the general population (RR 0.70; 95% CI 0.66-0.74) compared to patients with diabetes mellitus (RR 0.72; 95% CI 0.61-0.86) and among those patients treated with DHP-CCBs (RR 0.69; 95% CI 0.63-0.74) compared to patients treated with non-DHP-CCBs (RR 0.72; 95% CI 0.67-0.78). Conclusion: CCBs may reduce the risk of active TB in patients with diabetes and the general population. On the contrary, CCBs do not seem to have a protective effect on tuberculosis-related mortality. However, more evidence is still needed. We recommend developing clinical trials to verify these findings, including more diverse populations. Systematic Review Registration: [https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=352129].

Real-world impact of the fixed-dose combination on improving treatment outcomes of drug-susceptible tuberculosis: a comparative study using multiyear national tuberculosis patient data

BACKGROUND

The fixed-dose combination (FDC) for first-line antituberculosis (TB) treatment has long been a standard practice worldwide; however, there is limited evidence on whether the use of FDC improves long-term treatment outcomes in the real-world setting.

METHODS

We identified 32 239 newly diagnosed patients with drug-susceptible (DS) TB in 2015 and 2016 who had been prescribed FDC or non-FDC TB treatment from a multiyear (2013-2018) national TB cohort database that linked the Korean National Tuberculosis Surveillance System, the National Health Insurance Database and the Health Insurance Review and Assessment Service database. Inverse probability of treatment weighting (IPTW) with a propensity score was used to control for differences in patient characteristics between 5926 patients with TB treated with FDC and 26 313 patients with non-FDC. Multivariable logistic regression analyses were performed to assess for the factors influencing treatment outcomes between the two groups.

RESULTS

After IPTW, new patients with DS-TB treated with FDC had higher treatment completion rate (83.9% vs 78.9%, p<0.01) and lower death rates (8.2% vs 9.8%, p<0.01) with similar TB recurrence rate (2.3% vs 2.4%) compared with those treated with non-FDC. In multivariable analyses, FDC use had higher odds treatment completion (adjusted OR 1.45; 95% CI 1.34 to 1.56). Patients with TB with younger age (relative to 70+ age) and higher income level had higher odds for treatment completion. Use of FDC did not influence TB recurrence after treatment completion (adjusted HR 0.94; 95% CI 0.77 to 1.16). The acquired drug resistance rate was similar between the two groups (drug-resistant TB in FDC 4.7% vs non-FDC 5.3%; p=0.80).

CONCLUSION

In Korea, prescription of FDC to treat newly diagnosed patients with DS TB improved patient's treatment completion. Use of FDC did not increase the risks of TB recurrence or development of drug resistance.

Unveiling the Clinical Diversity in Nontuberculous Mycobacteria (NTM) Infections: A Comprehensive Review

Once considered rare, nontuberculous mycobacterial (NTM) infections have garnered increasing attention in recent years. This comprehensive review provides insights into the epidemiology, clinical diversity, diagnostic methods, treatment strategies, prevention, and emerging research trends in NTM infections. Key findings reveal the global prevalence of NTM infections, their diverse clinical presentations affecting respiratory and extra-pulmonary systems, and the diagnostic challenges addressed by advances in microbiological, radiological, and immunological methods. Treatment complexities, especially drug resistance and patient adherence, are discussed, along with the vulnerability of special populations. The importance of early detection and management is underscored. Prospects in NTM research, including genomics, diagnostics, drug development, and multidisciplinary approaches, promise to enhance our understanding and treatment of these infections. This review encapsulates the multifaceted nature of NTM infections, offering a valuable resource for clinicians, researchers, and public health professionals.

Tuberculosis in older adults: challenges and best practices in the Western Pacific Region

The Western Pacific has one of the fastest-growing older adult populations globally, and tuberculosis (TB) remains one of the foremost infectious causes of disease and death in the region. Older adults are at higher risk of TB due to immunosenescence, comorbidities, and increased institutionalisation. Atypical symptoms and reduced access to health services may delay care-seeking and TB diagnosis, while co-morbidity and increased risk of adverse drug reactions complicate TB treatment. Post-TB sequelae and socioeconomic challenges may decrease the quality of life after TB treatment completion. Despite their high disease burden and special challenges, there is a lack of regionally coordinated policies and guidelines to manage TB among older adults. Routine TB screening at aged-care facilities, age-friendly infrastructure and services, awareness of atypical TB features, integration of TB and non-communicable diseases services, and person-centred approaches to treatment support could improve TB management among older adults. Addressing these challenges and adopting the best practices identified should inform policy formulation and implementation.

Funding

This project was funded by 1) the World Health Organization Regional Office for the Western Pacific, with financial contributions from the Government of the Republic of Korea through the Korean Disease Control and Prevention Agency and the Government of Japan through the Ministry of Health, Labour and Welfare, and 2) NUS Start-up Grant. The funders had no role in the paper design, collection, analysis, and interpretation of data and in writing of the paper.

Tuberculosis in older adults: case studies from four countries with rapidly ageing populations in the western pacific region

BACKGROUND

The Western Pacific Region has one of the fastest-growing populations of older adults (≥ 65 years) globally, among whom tuberculosis (TB) poses a particular concern. This study reports country case studies from China, Japan, the Republic of Korea, and Singapore reflecting on their experiences in managing TB among older adults.

FINDINGS

Across all four countries, TB case notification and incidence rates were highest among older adults, but clinical and public health guidance focused on this population was limited. Individual country reports illustrated a range of practices and challenges. Passive case finding remains the norm, with limited active case finding (ACF) programs implemented in China, Japan, and the Republic of Korea. Different approaches have been trialled to assist older adults in securing an early diagnosis, as well as adhering to their TB treatment. All countries emphasised the need for person-centred approaches that include the creative application of new technology and tailored incentive programs, as well as reconceptualisation of how we provide treatment support. The use of traditional medicines was found to be culturally entrenched among older adults, with a need for careful consideration of their complementary use. TB infection testing and the provision of TB preventive treatment (TPT) were underutilised with highly variable practice.

CONCLUSION

Older adults require specific consideration in TB response policies, given the burgeoning aging population and their high TB risk. Policymakers, TB programs and funders must invest in and develop locally contextualised practice guidelines to inform evidence-based TB prevention and care practices for older adults.

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.

Costs Associated with Adverse Drug Reactions Among HIV/TB Patients in Thailand

Purpose

To assess the direct and indirect costs associated with adverse drug reactions (ADRs) in patients receiving treatment regimens for human immunodeficiency virus (HIV) infection and tuberculosis (TB) in selected Thai hospitals.

Patients and Methods

This was a retrospective study conducted between October 2014 and September 2019 at three public hospitals in Thailand. Data were obtained from a medical database and spontaneous ADR reporting system of each study site. The out-of-pocket health payments and indirect costs were determined via interviewing. All costs were updated to 2021.

Results

A total of 432 eligible patients who experienced ADRs due to HIV and TB treatment, and 93 patients were interviewed to determine direct non-medical and indirect costs. The average direct medical cost for ADR was USD 5.65 for mild cases, USD 156.54 for moderate cases, and USD 1,242.45 for severe cases. For direct non-medical costs, the average cost per episode was USD 27.29 in mild ADR, USD 70.86 in moderate ADR and USD 270.66 in severe ADR. The indirect cost incurred in each mild, moderate and severe ADR was USD 41.86, USD 89.34, and USD 552.60, respectively. The Stevens-Johnson syndrome (SJS) had the highest management costs.

Conclusion

ADRs associated with anti-tuberculosis drugs and antiretroviral drugs seem to have a substantial economic impact from a societal perspective. These findings would be useful for increasing awareness and encouraging early avoidance of ADRs.

Further insights into to the role of statins against active tuberculosis: systematic review and meta-analysis

OBJECTIVES

Tuberculosis is a major cause of global morbidity and mortality. Statins could be associated with a lower risk of some infectious diseases, including tuberculosis. Statins could reduce the risk of latent tuberculosis infection and active tuberculosis, acting as an adjuvant in treating tuberculosis. This study aimed to determine if statins reduce the risk of active tuberculosis.

METHODS

We systematically analyzed 8 databases from inception to December 2021. We included articles without language restriction if they met our inclusion and exclusion criteria and the PECO strategy (Population: adults without active pulmonary tuberculosis; Exposure: treatment with any statin; Comparator: no use of statins; Outcome: active tuberculosis). Odds Ratios (ORs) with 95% confidence intervals (CIs) were pooled using random- effects models regardless of heterogeneity quantified by Cochran's Q and I² statistics. We performed subgroup analyses according to the participants' diabetic status and follow-up length (≤10 years or >10 years).

RESULTS

Twelve articles reporting observational studies involving 3.038.043 participants, including at least 32.668 cases of active tuberculosis. Eight reported retrospective cohort studies, three nested case-control study, and one was a case control study.According to our meta-analysis, statins may reduce the risk of active tuberculosis, in the general population (OR 0.66; 95% CI, 0.54-0.81), in non-diabetic (OR 0.66; 95% CI, 0.54-0.80) and in diabetic patients (OR 0.65; 95% CI, 0.49-0.87). This protective effect did not differ according to the participants' diabetic status nor follow-up length (test for subgroup differences I²=0). We found significant clinical and methodological heterogeneity. Similarly, the forest plot, and the I² and Chi² statistics suggested considerable statistical heterogeneity (I²=95%, p<0.05, respectively). Of the 12 included studies, 9 were at low risk of bias and 3 were at high risk of bias. Similarly, according to the funnel plot, it is very likely that there are important publication biases.

CONCLUSION

Statin use may significantly reduce the risk of tuberculosis in the general population, diabetic and non-diabetic patients. Nevertheless, caution should be exercised when interpreting these conclusions, due to the quality of the evidence, the heterogeneity of the studies, the presence of bias, and the difficulty in extrapolating these results to populations of other races and ethnicities.

Treatment Adherence among Tuberculosis patients: A Concept Analysis

BACKGROUND OF THE STUDY: The principal difficulty of long-term tuberculosis (TB) treatment is patient nonadherence. During pandemic, nonadherence of TB treatment affects mortality since TB patients are more vulnerable with Covid-19. AIM OF THE STUDY: The purpose of this concept analysis was to clarify and analyze the concept of treatment adherence. METHODOLOGY: Analysis concept was conducted using the Walker and Avant’s method from relevant studies published by EBSCO, PubMed, ProQuest, Wiley Online Library, and Springer between  2003 - 2021. RESULTS:  Five attributes characterizing the concept of treatment adherence from thirteen articles were identified: individual behavior, relationship, mutual participation, shared decision making, and agreement. CONCLUSION: This concept analysis revealed that TB treatment adherence involves many aspects, including the patient, family, society, health care professionals, and policy. These findings help to understand the contribution of major attributes, thereby promoting the body of knowledge on TB and contributing to its elimination during COVID-19 pandemic.

A Systematic Review of Economic Evaluations of Active Tuberculosis Treatments

Background: The disease burden of active tuberculosis (TB) is considerable, but systematic reviews of economic evaluations of active TB treatments are scarce. Methods: PubMed, EMBASE, and the Cochrane Library databases were used to search for articles on cost-effectiveness analysis or cost-utility analysis that economically evaluated active TB treatments, which were then systematically reviewed by two independent reviewers. We extracted vital components of the included studies, such as country, population, intervention/comparator, primary outcome, values of outcomes, thresholds, model type, time horizon, and health states included in the model. Results: Seventeen studies were included in this systematic review. Thirteen dealt with interventions of medications, and the remaining four compared care strategies. The Markov model was the most commonly used tool to compare medications, whereas studies on care plans mainly used decision trees. The most commonly used primary outcome was disability-adjusted life years, followed by quality-adjusted life years. For treatment-naïve TB, the 4-month regimen was more cost-effective than the 6-month regimen mainly in low- and middle-income countries. For multidrug-resistant TB, a bedaquiline-based regimen was cost-effective. For multidrug-resistant TB, decentralized care that employed the use of home or mobile devices was more cost-effective than hospital-based centralized care in low- and middle-income countries. Conclusion: New treatment strategies to improve therapeutic outcomes by enhancing treatment adherence, such as regimens with shorter durations (2 or 4 months) and decentralized care, or new anti-TB agents (e.g., bedaquiline) have been suggested as cost-effective interventions for active TB. This review provides information on the economic evaluation of active TB from good-quality studies, thus aiding the future economic evaluation of active TB.

Determinant factors for loss to follow-up in drug-resistant tuberculosis patients: the importance of psycho-social and economic aspects

Background

Drug-resistant tuberculosis (DR-TB) is the barrier for global TB elimination efforts with a lower treatment success rate. Loss to follow-up (LTFU) in DR-TB is a serious problem, causes mortality and morbidity for patients, and leads to wide spreading of DR-TB to their family and the wider community, as well as wasting health resources. Prevention and management of LTFU is crucial to reduce mortality, prevent further spread of DR-TB, and inhibit the development and transmission of more extensively drug-resistant strains of bacteria. A study about the factors associated with loss to follow-up is needed to develop appropriate strategies to prevent DR-TB patients become loss to follow-up. This study was conducted to identify the factors correlated with loss to follow-up in DR-TB patients, using questionnaires from the point of view of patients.

Methods

An observational study with a cross-sectional design was conducted. Study subjects were all DR-TB patients who have declared as treatment success and loss to follow-up from DR-TB treatment. A structured questionnaire was used to collect information by interviewing the subjects as respondents. Obtained data were analyzed potential factors correlated with loss to follow-up in DR-TB patients.

Results

A total of 280 subjects were included in this study. Sex, working status, income, and body mass index showed a significant difference between treatment success and loss to follow-up DR-TB patients with p-value of 0.013, 0.010, 0.007, and 0.006, respectively. In regression analysis, factors correlated with increased LTFU were negative attitude towards treatment (OR = 1.2; 95% CI = 1.1–1.3), limitation of social support (OR = 1.1; 95% CI = 1.0–1.2), dissatisfaction with health service (OR = 2.1; 95% CI = 1.5–3.0)), and limitation of economic status (OR = 1.1; 95% CI = 1.0–1.2)).

Conclusions

Male patients, jobless, non-regular employee, lower income, and underweight BMI were found in higher proportion in LTFU patients. Negative attitude towards treatment, limitation of social support, dissatisfaction with health service, and limitation of economic status are factors correlated with increased LTFU in DR-TB patients. Non-compliance to treatment is complex, we suggest that the involvement and support from the combination of health ministry, labor and employment ministry, and social ministry may help to resolve the complex problems of LTFU in DR-TB patients.

Wastewater-Based Surveillance of Antibiotic Resistance Genes Associated with Tuberculosis Treatment Regimen in KwaZulu Natal, South Africa

Essential components of public health include strengthening the surveillance of infectious diseases and developing early detection and prevention policies. This is particularly important for drug-resistant tuberculosis (DR-TB), which can be explored by using wastewater-based surveillance. This study aimed to use molecular techniques to determine the occurrence and concentration of antibiotic-resistance genes (ARGs) associated with tuberculosis (TB) resistance in untreated and treated wastewater. Raw/untreated and treated (post-chlorination) wastewater samples were taken from three wastewater treatment plants (WWTPs) in South Africa. The ARGs were selected to target drugs used for first- and second-line TB treatment. Both conventional polymerase chain reaction (PCR) and the more advanced droplet digital PCR (ddPCR) were evaluated as surveillance strategies to determine the distribution and concentration of the selected ARGs. The most abundant ARG in the untreated wastewater was the rrs gene, associated with resistance to the aminoglycosides, specifically streptomycin, with median concentration ranges of 4.69–5.19 log copies/mL. In contrast, pncA gene, associated with resistance to the TB drug pyrazinamide, was the least detected (1.59 to 2.27 log copies/mL). Resistance genes associated with bedaquiline was detected, which is a significant finding because this is a new drug introduced in South Africa for the treatment of multi-drug resistant TB. This study, therefore, establishes the potential of molecular surveillance of wastewater for monitoring antibiotic resistance to TB treatment in communities.