Home-Based and Facility-Based Directly Observed Therapy of Tuberculosis Treatment under Programmatic Conditions in Urban Tanzania

Mapping the effectiveness of the community tuberculosis care programs: a systematic review

BACKGROUND

Tuberculosis is a significant global public health threat, especially in countries with limited resources. To improve tuberculosis care, the World Health Organization emphasizes the importance of considering a TB patient's journey across a variety of connected settings and facilities. A systematic review was conducted to map previously conducted studies to identify existing community TB implementation models, their effectiveness on cost, and treatment outcomes.

METHODS

Systematic search through various electronic databases MEDLINE, EBSCO (PsycINFO and CINAHL), Cochrane Library, EMBASE, WHO Regional Databases, gray literature, and hand-searched bibliographies was performed. Articles published in English between the years 2000 and 2022 with a substantial focus on community TB implementation models were considered for inclusion. Studies were excluded if the intervention was purely facility-based and those focusing exclusively on qualitative assessments. Two reviewers used standardized methods to screen titles, abstracts, and data charting. Included studies were assessed for quality using ROBINS-I and ROB 2. Analysis of study results uses a PRISMA flow diagram and quantitative approach.

RESULTS

A total of 6982 articles were identified with 36 meeting the eligibility criteria for analysis. Electronic medication monitors showed an increased probability of treatment success rate (RR 1.0-4.33 and the 95% CI 0.98-95.4) in four cohort studies in low- and middle-income countries with the incremental cost-effectiveness of $434. Four cohort studies evaluating community health worker direct observation therapy in low- and middle-income countries showed a treatment success risk ratio of up to 3.09 with a 95% CI of 0.06-7.88. (32,41,43,48) and incremental cost-effectiveness up to USS$410. Moreover, four comparative studies in low- and middle-income countries showed family directly observed treatment success risk ratio up to 9.07, 95% CI of 0.92-89.9. Furthermore, four short message service trials revealed a treatment success risk ratio ranging from 1.0 to 1.45 (95% CI fell within these values) with a cost-effectiveness of up to 350I$ compared to standard of care.

CONCLUSIONS

This review illustrates that community-based TB interventions such as electronic medication monitors, community health worker direct observation therapy, family directly observed treatment, and short message service can substantially bolster efficiency and convenience for patients and providers while reducing health system costs and improving clinical outcomes.

The Sputum Microbiome in Pulmonary Tuberculosis and Its Association With Disease Manifestations: A Cross-Sectional Study

Each day, approximately 27,000 people become ill with tuberculosis (TB), and 4,000 die from this disease. Pulmonary TB is the main clinical form of TB, and affects the lungs with a considerably heterogeneous manifestation among patients. Immunomodulation by an interplay of host-, environment-, and pathogen-associated factors partially explains such heterogeneity. Microbial communities residing in the host's airways have immunomodulatory effects, but it is unclear if the inter-individual variability of these microbial communities is associated with the heterogeneity of pulmonary TB. Here, we investigated this possibility by characterizing the microbial composition in the sputum of 334 TB patients from Tanzania, and by assessing its association with three aspects of disease manifestations: sputum mycobacterial load, severe clinical findings, and chest x-ray (CXR) findings. Compositional data analysis of taxonomic profiles based on 16S-rRNA gene amplicon sequencing and on whole metagenome shotgun sequencing, and graph-based inference of microbial associations revealed that the airway microbiome of TB patients was shaped by inverse relationships between Streptococcus and two anaerobes: Selenomonas and Fusobacterium. Specifically, the strength of these microbial associations was negatively correlated with Faith's phylogenetic diversity (PD) and with the accumulation of transient genera. Furthermore, low body mass index (BMI) determined the association between abnormal CXRs and community diversity and composition. These associations were mediated by increased abundance of Selenomonas and Fusobacterium, relative to the abundance of Streptococcus, in underweight patients with lung parenchymal infiltrates and in comparison to those with normal chest x-rays. And last, the detection of herpesviruses and anelloviruses in sputum microbial assemblage was linked to co-infection with HIV. Given the anaerobic metabolism of Selenomonas and Fusobacterium, and the hypoxic environment of lung infiltrates, our results suggest that in underweight TB patients, lung tissue remodeling toward anaerobic conditions favors the growth of Selenomonas and Fusobacterium at the expense of Streptococcus. These new insights into the interplay among particular members of the airway microbiome, BMI, and lung parenchymal lesions in TB patients, add a new dimension to the long-known association between low BMI and pulmonary TB. Our results also drive attention to the airways virome in the context of HIV-TB coinfection.

Mortality and associated factors among adult patients on tuberculosis treatment in Tanzania: A retrospective cohort study

INTRODUCTION

Tuberculosis (TB) is the global leading cause of death from an infectious agent. Tanzania is among the 30 high TB burden countries with a mortality rate of 47 per 100,000 population and a case fatality of 4%. This study assessed mortality rate, survival probabilities, and factors associated with death among adult TB patients on TB treatment in Tanzania.

METHODS

A retrospective cohort study was conducted utilizing case-based national TB program data of adult (≥15 years) TB cases enrolled on TB treatment from January 2017 to December 2017. We determined survival probabilities using the Kaplan-Meier estimator and a Cox proportional hazard model was used to identify independent risk factors of TB mortality. Hazard ratios and their respective 95% confidence intervals were reported.

RESULTS

Of 53,753 adult TB patients, 1927 (3.6%) died during TB treatment and the crude mortality rate was 6.31 per 1000 person-months. Male accounted for 33,297 (61.9%) of the study population and the median (interquartile range [IQR]) age was 40 (30-53) years. More than half 1027 (56.7%) of deaths occurred in first two months of treatment. Overall survival probabilities were 96%, and 92% at 6th and 12th month respectively. The independent risk factors for TB mortality among TB patients included: advanced age ≥ 45 years (adjusted hazard ratio (aHR) = 1.74, 95% confidence interval (CI) = 1.45-2.08); receiving service at the hospital level (aHR = 1.22, 95% CI = 1.09-1.36); TB/HIV co-infection (aHR = 2.51, 95% CI = 2.26-2.79); facility-based direct observed therapy (DOT) option (aHR = 2.23, 95% CI = 1.95-2.72); having bacteriological unconfirmed TB results (aHR = 1.58, 95% CI = 1.42-1.76); and other referral type (aHR = 1.44, 95% CI = 1.16-1.78).

CONCLUSION

Advanced age, TB/HIV co-infection, bacteriological unconfirmed TB results, other referral types, receiving service at facility-based DOT option and obtaining service at the hospital level were significant contributors to TB death in Tanzania. Appropriate targeted intervention to improve TB referral systems, improve diagnostic capacity in the primary health facilities, minimize delay and misdiagnosis of TB patients might reduce TB mortality.

Treatment outcomes of patients with drug-sensitive tuberculosis under community-based versus facility-based directly observed treatment, short course strategy in Southwest Ethiopia: a prospective cohort study

OBJECTIVE

To compare tuberculosis (TB) treatment outcomes and associated factors among patients attending community-based versus facility-based directly observed treatment, short course (DOTS).

DESIGN

A prospective cohort study.

SETTING

The study was conducted in Southwest Ethiopia. There were seven hospitals (five primary, one general and one specialised), 120 health centres and 494 health posts.

PARTICIPANTS

A total of 1161 individuals consented to participate in the study (387 patients under community-based DOTS (CB-DOTS) and 774 patients under facility-based DOTS (FB-DOTS)). Individuals who could not respond to the questions, mentally or critically ill patients, and those less than 15 years old, were excluded from the study.

PRIMARY OUTCOME MEASURE

TB treatment outcomes were compared among patients under CB-DOTS versus FB-DOTS. Risk ratio (RR), risk difference (RD) and confidence interval (CI) were calculated among the study groups. In addition, χ² or Fisher's exact tests were used to compare group differences, with a p value of <0.05 considered statistically significant.

RESULTS

Patients who opted for CB-DOTS were more likely to be cured by 12% than those who opted for FB-DOTS (RR=1.12, 95% CI=0.96 to 1.30). Patients under CB-DOTS had a lesser risk of death (RR=0.93, 95% CI=0.49 to 1.77) and a lower risk of treatment failure (RR=0.86, 95% CI=0.22 to 3.30) than those under FB-DOTS. Furthermore, patients who opted for CB-DOTS were less likely to have a positive sputum smear result at the end of the treatment period (p=0.042) compared with their counterparts.

CONCLUSION

The study showed that CB-DOTS is more effective than FB-DOTS in terms of improving cure rate and sputum conversion rate, as well as lowering treatment failure rate. Our findings show the need for scaling up and a further decentralisation of CB-DOTS approach to improve access to TB treatment service for the rural community.

Electronic pillbox-enabled self-administered therapy versus standard directly observed therapy for tuberculosis medication adherence and treatment outcomes in Ethiopia (SELFTB): protocol for a multicenter randomized controlled trial

BACKGROUND

To address the multifaceted challenges associated with tuberculosis (TB) in-person directly observed therapy (DOT), the World Health Organization recently recommended that countries maximize the use of digital adherence technologies. Sub-Saharan Africa needs to investigate the effectiveness of such technologies in local contexts and proactively contribute to global decisions around patient-centered TB care. This study aims to evaluate the effectiveness of pillbox-enabled self-administered therapy (SAT) compared to standard DOT on adherence to TB medication and treatment outcomes in Ethiopia. It also aims to assess the usability, acceptability, and cost-effectiveness of the intervention from the patient and provider perspectives.

METHODS

This is a multicenter, randomized, controlled, open-label, superiority, effectiveness-implementation hybrid, mixed-methods, two-arm trial. The study is designed to enroll 144 outpatients with new or previously treated, bacteriologically confirmed, drug-sensitive pulmonary TB who are eligible to start the standard 6-month first-line anti-TB regimen. Participants in the intervention arm (n = 72) will receive 15 days of HRZE-isoniazid, rifampicin, pyrazinamide, and ethambutol-fixed-dose combination therapy in the evriMED500 medication event reminder monitor device for self-administration. When returned, providers will count any remaining tablets in the device, download the pill-taking data, and refill based on preset criteria. Participants can consult the provider in cases of illness or adverse events outside of scheduled visits. Providers will handle participants in the control arm (n = 72) according to the standard in-person DOT. Both arms will be followed up throughout the 2-month intensive phase. The primary outcomes will be medication adherence and sputum conversion. Adherence to medication will be calculated as the proportion of patients who missed doses in the intervention (pill count) versus DOT (direct observation) arms, confirmed further by IsoScreen urine isoniazid test and a self-report of adherence on eight-item Morisky Medication Adherence Scale. Sputum conversion is defined as the proportion of patients with smear conversion following the intensive phase in intervention versus DOT arms, confirmed further by pre-post intensive phase BACTEC MGIT TB liquid culture. Pre-post treatment MGIT drug susceptibility testing will determine whether resistance to anti-TB drugs could have impacted culture conversion. Secondary outcomes will include other clinical outcomes (treatment not completed, death, or loss to follow-up), cost-effectiveness-individual and societal costs with quality-adjusted life years-and acceptability and usability of the intervention by patients and providers.

DISCUSSION

This study will be the first in Ethiopia, and of the first three in sub-Saharan Africa, to determine whether electronic pillbox-enabled SAT improves adherence to TB medication and treatment outcomes, all without affecting the inherent dignity and economic wellbeing of patients with TB.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT04216420. Registered on 2 January 2020.

Factors predictive of the success of tuberculosis treatment: A systematic review with meta-analysis

OBJECTIVE

To produce pooled estimates of the global results of tuberculosis (TB) treatment and analyze the predictive factors of successful TB treatment.

METHODS

Studies published between 2014 and 2019 that reported the results of the treatment of pulmonary TB and the factors that influenced these results. The quality of the studies was evaluated according to the Newcastle-Ottawa quality assessment scale. A random effects model was used to calculate the pooled odds ratio (OR) and 95% confidence interval (CI). This review was registered in the International Prospective Register of Systematic Reviews (PROSPERO) in February 2019 under number CRD42019121512.

RESULTS

A total of 151 studies met the criteria for inclusion in this review. The success rate for the treatment of drug-sensitive TB in adults was 80.1% (95% CI: 78.4-81.7). America had the lowest treatment success rate, 75.9% (95% CI: 73.8-77.9), and Oceania had the highest, 83.9% (95% CI: 75.2-91.0). In children, the success rate was 84.8% (95% CI: 77.7-90.7); in patients coinfected with HIV, it was 71.0% (95% CI: 63.7-77.8), in patients with multidrug-resistant TB, it was 58.4% (95% CI: 51.4-64.6), in patients with and extensively drug-resistant TB it was 27.1% (12.7-44.5). Patients with negative sputum smears two months after treatment were almost three times more likely to be successfully treated (OR 2.7; 1.5-4.8), whereas patients younger than 65 years (OR 2.0; 1.7-2.4), nondrinkers (OR 2.0; 1.6-2.4) and HIV-negative patients (OR 1.9; 1.6-2.5 3) were two times more likely to be successfully treated.

CONCLUSION

The success of TB treatment at the global level was good, but was still below the defined threshold of 85%. Factors such as age, sex, alcohol consumption, smoking, lack of sputum conversion at two months of treatment and HIV affected the success of TB treatment.

Adherence interventions and outcomes of tuberculosis treatment: A systematic review and meta-analysis of trials and observational studies

BACKGROUND

Incomplete adherence to tuberculosis (TB) treatment increases the risk of delayed culture conversion with continued transmission in the community, as well as treatment failure, relapse, and development or amplification of drug resistance. We conducted a systematic review and meta-analysis of adherence interventions, including directly observed therapy (DOT), to determine which approaches lead to improved TB treatment outcomes.

METHODS AND FINDINGS

We systematically reviewed Medline as well as the references of published review articles for relevant studies of adherence to multidrug treatment of both drug-susceptible and drug-resistant TB through February 3, 2018. We included randomized controlled trials (RCTs) as well as prospective and retrospective cohort studies (CSs) with an internal or external control group that evaluated any adherence intervention and conducted a meta-analysis of their impact on TB treatment outcomes. Our search identified 7,729 articles, of which 129 met the inclusion criteria for quantitative analysis. Seven adherence categories were identified, including DOT offered by different providers and at various locations, reminders and tracers, incentives and enablers, patient education, digital technologies (short message services [SMSs] via mobile phones and video-observed therapy [VOT]), staff education, and combinations of these interventions. When compared with DOT alone, self-administered therapy (SAT) was associated with lower rates of treatment success (CS: risk ratio [RR] 0.81, 95% CI 0.73-0.89; RCT: RR 0.94, 95% CI 0.89-0.98), adherence (CS: RR 0.83, 95% CI 0.75-0.93), and sputum smear conversion (RCT: RR 0.92, 95% CI 0.87-0.98) as well as higher rates of development of drug resistance (CS: RR 4.19, 95% CI 2.34-7.49). When compared to DOT provided by healthcare providers, DOT provided by family members was associated with a lower rate of adherence (CS: RR 0.86, 95% CI 0.79-0.94). DOT delivery in the community versus at the clinic was associated with a higher rate of treatment success (CS: RR 1.08, 95% CI 1.01-1.15) and sputum conversion at the end of two months (CS: RR 1.05, 95% CI 1.02-1.08) as well as lower rates of treatment failure (CS: RR 0.56, 95% CI 0.33-0.95) and loss to follow-up (CS: RR 0.63, 95% CI 0.40-0.98). Medication monitors improved adherence and treatment success and VOT was comparable with DOT. SMS reminders led to a higher treatment completion rate in one RCT and were associated with higher rates of cure and sputum conversion when used in combination with medication monitors. TB treatment outcomes improved when patient education, healthcare provider education, incentives and enablers, psychological interventions, reminders and tracers, or mobile digital technologies were employed. Our findings are limited by the heterogeneity of the included studies and lack of standardized research methodology on adherence interventions.

CONCLUSION

TB treatment outcomes are improved with the use of adherence interventions, such as patient education and counseling, incentives and enablers, psychological interventions, reminders and tracers, and digital health technologies. Trained healthcare providers as well as community delivery provides patient-centered DOT options that both enhance adherence and improve treatment outcomes as compared to unsupervised, SAT alone.

Anemia in tuberculosis cases and household controls from Tanzania: Contribution of disease, coinfections, and the role of hepcidin

Background

Tuberculosis (TB) induces a systemic inflammatory state affecting iron homeostasis. Patients with TB often have additional comorbidities such as anemia which can result in poorer treat outcomes. We studied the contribution of anemia and the role of the iron regulatory hormone hepcidin among TB patients and household contacts.

Methods

We analyzed serum samples from 102 TB cases and 98 controls without TB, matched by age/sex, for hepcidin, iron, and inflammation parameters. Five controls developed TB within 12 months. We used linear regression to assess associations.

Results

Anemia of chronic disease (ACD) was more frequent among cases than controls (59.8% vs. 26.1%), but iron-deficiency anemia more frequent in controls (10% vs. 1%). The median hepcidin level was higher in cases than controls (63.7 vs. 14.2 ng/mL), but coinfections with HIV, helminths, and respiratory pathogens did not show cumulative effects. Hepcidin was associated with more severe TB symptom scoring (coefficient 0.8, 95% confidence interval [CI] 0.5–1.2) and higher mycobacterial load (0.7, 95% CI 0.4–1.0). Hepcidin was higher in TB cases and controls who developed TB compared to controls without TB (p<0.001), even when restricting to HIV-negative study participants.

Conclusions

ACD was the predominate etiology in TB patients suggesting limited benefit from iron supplementation. Increased hepcidin levels long before active disease, indicating altered iron metabolism, may be a marker for developing disease among TB-exposed individuals. Clinical management of anemia and nutrition interventions in TB patients need to be considered to improve the clinical course and outcomes.

Prevalence and clinical relevance of helminth co-infections among tuberculosis patients in urban Tanzania

BACKGROUND

Helminth infections can negatively affect the immunologic host control, which may increase the risk of progression from latent Mycobacterium tuberculosis infection to tuberculosis (TB) disease and alter the clinical presentation of TB. We assessed the prevalence and determined the clinical relevance of helminth co-infection among TB patients and household contact controls in urban Tanzania.

METHODOLOGY

Between November 2013 and October 2015, we enrolled adult (≥18 years) sputum smear-positive TB patients and household contact controls without TB during an ongoing TB cohort study in Dar es Salaam, Tanzania. We used Baermann, FLOTAC, Kato-Katz, point-of-care circulating cathodic antigen, and urine filtration to diagnose helminth infections. Multivariable logistic regression models with and without random effects for households were used to assess for associations between helminth infection and TB.

PRINCIPAL FINDINGS

A total of 597 TB patients and 375 household contact controls were included. The median age was 33 years and 60.2% (585/972) were men. The prevalence of any helminth infection among TB patients was 31.8% (190/597) and 25.9% (97/375) among controls. Strongyloides stercoralis was the predominant helminth species (16.6%, 161), followed by hookworm (9.0%, 87) and Schistosoma mansoni (5.7%, 55). An infection with any helminth was not associated with TB (adjusted odds ratio (aOR) 1.26, 95% confidence interval (CI): 0.88-1.80, p = 0.22), but S. mansoni infection was (aOR 2.15, 95% CI: 1.03-4.45, p = 0.040). Moreover, S. mansoni infection was associated with lower sputum bacterial load (aOR 2.63, 95% CI: 1.38-5.26, p = 0.004) and tended to have fewer lung cavitations (aOR 0.41, 95% CI: 0.12-1.16, p = 0.088).

CONCLUSIONS/SIGNIFICANCE

S. mansoni infection was an independent risk factor for active TB and altered the clinical presentation in TB patients. These findings suggest a role for schistosomiasis in modulating the pathogenesis of human TB. Treatment of helminths should be considered in clinical management of TB and TB control programs.