Outcomes and follow-up of patients treated for multidrug-resistant tuberculosis in Orel, Russia, 2002-2005

Estimating Post-treatment Recurrence After Multidrug-Resistant Tuberculosis Treatment Among Patients With and Without Human Immunodeficiency Virus: The Impact of Assumptions About Death and Missing Follow-up

BACKGROUND

Quantification of recurrence risk following successful treatment is crucial to evaluating regimens for multidrug- or rifampicin-resistant (MDR/RR) tuberculosis (TB). However, such analyses are complicated when some patients die or become lost during post-treatment follow-up.

METHODS

We analyzed data on 1991 patients who successfully completed a longer MDR/RR-TB regimen containing bedaquiline and/or delamanid between 2015 and 2018 in 16 countries. Using 5 approaches for handling post-treatment deaths, we estimated 6-month post-treatment TB recurrence risk overall and by HIV status. We used inverse-probability weighting to account for patients with missing follow-up and investigated the impact of potential bias from excluding these patients without applying inverse-probability weights.

RESULTS

The estimated TB recurrence risk was 7.4/1000 (95% credible interval: 3.3-12.8) when deaths were handled as non-recurrences and 7.6/1000 (3.3-13.0) when deaths were censored and inverse-probability weights were applied to account for the excluded deaths. The estimated risks of composite recurrence outcomes were 25.5 (15.3-38.1), 11.7 (6.4-18.2), and 8.6 (4.1-14.4) per 1000 for recurrence or (1) any death, (2) death with unknown or TB-related cause, or (3) TB-related death, respectively. Corresponding relative risks for HIV status varied in direction and magnitude. Exclusion of patients with missing follow-up without inverse-probability weighting had a small impact on estimates.

CONCLUSIONS

The estimated 6-month TB recurrence risk was low, and the association with HIV status was inconclusive due to few recurrence events. Estimation of post-treatment recurrence will be enhanced by explicit assumptions about deaths and appropriate adjustment for missing follow-up data.

Global treatment outcomes of extensively drug-resistant tuberculosis in adults: A systematic review and meta-analysis

INTRODUCTION

Historically, extensively drug-resistant tuberculosis has been notoriously difficult to treat with devasting outcomes. As we are coming to the end of an era where the 2006 extensively drug-resistant tuberculosis definitions and old treatment regimens are being replaced, we aimed to estimate the proportion of extensively drug-resistant tuberculosis patients globally who achieved successful treatment outcomes.

METHODS

We conducted a systematic review of PubMed/MEDLINE, Scopus, Web of Science, and Embase from January 1, 2005, through April 3, 2023. Included studies reported WHO treatment outcomes, or adaptions hereof, for pre-extensively and/or extensively drug-resistant tuberculosis patients according to the 2006 WHO definition. Eligible studies included cohorts of at least 10 adults (aged>18 years) that were not pregnant. Using a random-effects model, we calculated pooled proportions of treatment outcomes and performed sensitivity and subgroup analyses. PROSPERO registration number: CRD42022340961.

RESULTS

Among 5056 studies reviewed, we identified 94 studies from 26 countries, involving 10,223 extensively drug-resistant tuberculosis patients. The pooled proportion of successful treatment outcomes was 44.2% (95%CI: 38.3-50.3). Sensitivity analyses consistently produced similar estimates. A slight improvement in treatment outcomes was observed after 2013. Furthermore, 25 studies reported outcomes for 3564 individuals with pre-extensively drug-resistant tuberculosis, of which 63.3% achieved successful treatment (95%CI: 43.1-72.5).

CONCLUSION

Globally, the success rate of extensively drug-resistant tuberculosis treatment is 44.2%, far below the WHO's target rate of 75%. These results may serve as a reference for future studies assessing extensively drug-resistant tuberculosis treatment outcomes under the 2021 definition treated with better treatment regimens available. Comprehensive surveillance data of extensively drug-resistant tuberculosis outcomes from the whole world are desirable to monitor treatment progress.

Effectiveness of Bedaquiline Use beyond Six Months in Patients with Multidrug-Resistant Tuberculosis

Rationale: Current recommendations for the treatment of rifampicin- and multidrug-resistant tuberculosis include bedaquiline (BDQ) used for 6 months or longer. Evidence is needed to inform the optimal duration of BDQ. Objectives: We emulated a target trial to estimate the effect of three BDQ duration treatment strategies (6, 7-11, and ⩾12 mo) on the probability of successful treatment among patients receiving a longer individualized regimen for multidrug-resistant tuberculosis. Methods: To estimate the probability of successful treatment, we implemented a three-step approach comprising cloning, censoring, and inverse probability weighting. Measurements and Main Results: The 1,468 eligible individuals received a median of 4 (interquartile range, 4-5) likely effective drugs. In 87.1% and 77.7% of participants, this included linezolid and clofazimine, respectively. The adjusted probability of successful treatment was 0.85 (95% confidence interval [CI], 0.81-0.88) for 6 months of BDQ, 0.77 (95% CI, 0.73-0.81) for 7-11 months, and 0.86 (95% CI, 0.83-0.88) for ⩾12 months. Compared with 6 months of BDQ, the ratio of treatment success was 0.91 (95% CI, 0.85-0.96) for 7-11 months and 1.01 (95% CI, 0.96-1.06) for ⩾12 months. Naive analyses that did not account for bias revealed a higher probability of successful treatment with ⩾12 months (ratio, 1.09 [95% CI, 1.05-1.14]). Conclusions: BDQ use beyond 6 months did not increase the probability of successful treatment among patients receiving longer regimens that commonly included new and repurposed drugs. When not properly accounted for, immortal person-time bias can influence estimates of the effects of treatment duration. Future analyses should explore the effect of treatment duration of BDQ and other drugs in subgroups with advanced disease and/or receiving less potent regimens.

Estimating post-treatment recurrence after multidrug-resistant tuberculosis treatment among patients with and without HIV: the impact of assumptions about death and missing follow-up

Background

Quantification of recurrence risk following successful treatment is crucial to evaluating regimens for multidrug- or rifampicin-resistant (MDR/RR) tuberculosis (TB). However, such analyses are complicated when some patients die or become lost during post-treatment-follow-up.

Methods

We analyzed data on 1,991 patients who successfully completed a longer MDR/RR-TB regimen containing bedaquiline and/or delamanid between 2015 and 2018 in 16 countries. Using five approaches for handling post-treatment deaths, we estimated the six-month post-treatment TB recurrence risk overall, and by HIV status. We used inverse-probability-weighting to account for patients with missing follow-up and investigated the impact of potential bias from excluding these patients without applying inverse-probability weights.

Results

The estimated TB recurrence risk was 6.6 per 1000 (95% confidence interval (CI):3.2,11.2) when deaths were handled as non-recurrences, and 6.7 per 1000 (95% CI:2.8,12.2) when deaths were censored and inverse-probability weights were applied to account for the excluded deaths. The estimated risk of composite recurrence outcomes were 24.2 (95% CI:14.1,37.0), 10.5 (95% CI:5.6,16.6), and 7.8 (95% CI:3.9,13.2) per 1000 for recurrence or 1) any death, 2) death with unknown or TB-related cause, 3) TB-related death, respectively. Corresponding relative risks for HIV status varied in direction and magnitude. Exclusion of patients with missing follow-up without inverse-probability-weighting had a small but apparent impact on estimates.

Conclusion

The estimated six-month TB recurrence risk was low, and the association with HIV status was inconclusive due to few recurrence events. Estimation of post-treatment recurrence will be enhanced by explicit assumptions about deaths and appropriate adjustment for missing follow-up data.

Brief psychotherapy administered by non-specialised health workers to address risky substance use in patients with multidrug-resistant tuberculosis: a feasibility and acceptability study

BACKGROUND

Only 55% of multidrug-resistant tuberculosis (MDR-TB) cases worldwide complete treatment, with problem substance use a risk for default and treatment failure. Nevertheless, there is little research on psychotherapeutic interventions for reducing substance use amongst MDR-TB patients, in general, and on their delivery by non-specialist health workers in particular.

OBJECTIVES

To explore the feasibility and acceptability of a non-specialist health worker-delivered 4-session brief motivational interviewing and relapse prevention (MI-RP) intervention for problem substance use and to obtain preliminary data on the effects of this intervention on substance use severity, depressive symptoms, psychological distress and functional impairment at 3 months after hospital discharge.

METHODS

Between December 2015 and October 2016, consenting MDR-TB patients admitted to Brewelskloof Hospital who screened at moderate to severe risk for substance-related problems on the Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) were enrolled, and a baseline questionnaire administered. In the 4 weeks prior to planned discharge, trained counsellors delivered the MI-RP intervention. The baseline questionnaire was re-administered 3 months post-discharge and qualitative interviews were conducted with a randomly selected sample of participants (n = 10).

RESULTS

Sixty patients were screened: 40 (66%) met inclusion criteria of which 39 (98%) were enrolled. Of the enrolled patients, 26 (67%) completed the counselling sessions and the final assessment. Qualitative interviews revealed participants' perceptions of the value of the intervention. From baseline to follow-up, patients reported reductions in substance use severity, symptoms of depression, distress and functional impairment.

CONCLUSION

In this feasibility study, participant retention in the study was moderate. We found preliminary evidence supporting the benefits of the intervention for reducing substance use and symptoms of psychological distress, supported by qualitative reports of patient experiences. Randomised studies are needed to demonstrate efficacy of this intervention before considering potential for wider implementation.

TRIAL REGISTRATION

South African National Clinical Trials Register ( DOH-27-0315-5007 ) on 01/04/2015 ( http://www.sanctr.gov.za ).

Prevalence and associated factors for alcohol use disorder among tuberculosis patients: a systematic review and meta-analysis study

BACKGROUND

Alcohol use disorders (AUD) in tuberculosis patients are complicated with poor compliance to anti-tuberculosis treatment and poor tuberculosis treatment outcomes. However, aggregate data concerning this problem is not available. Therefore, this review aimed to fill the above gap by generating an average prevalence of AUD in tuberculosis patients.

METHOD

Our electronic search for original articles was conducted in the databases of Scopus, PubMed, and EMBASE, African Index Medicus, and psych-info. Besides, the reference list of selected articles was looked at manually to have further eligible articles for the prevalence and associated factors of AUD in tuberculosis patients. The random-effects model was employed during the analysis. MS-Excel was used to extract data and stata-11 to determine the average prevalence of AUD among tuberculosis patients. A sub-group analysis and sensitivity analysis were also run. A visual inspection of the funnel plots and an Eggers publication bias plot test were checked for the presence of publication bias.

RESULT

A search of the electronic and manual system resulted in 1970 articles. After removing duplicates and unoriginal articles, only 28 articles that studied 30,854 tuberculosis patients met the inclusion criteria. The average estimated prevalence of AUD in tuberculosis patients was 30% (95% CI: 24.00, 35.00). This was with a slight heterogeneity (I2 = 57%, p-value < 0.001). The prevalence of AUD in tuberculosis patients was higher in Asia and Europe; 37% than the prevalence in the US and Africa; 24%. Besides, the average prevalence of AUD was 39, 30, 30, and 20% in studies with case-control, cohort, cross-sectional and experimental in design respectively. Also, the prevalence of AUD was higher in studies with the assessment tool not reported (36%) than studies assessed with AUDIT. AUD was also relatively higher in studies with a mean age of ≥40 years (42%) than studies with a mean age < 40 years (24%) and mean age not reported (27%). Based on a qualitative review; the male gender, older age, being single, unemployment, low level of education and income from socio-demographic variables, retreatment and treatment failure patients, stigma, and medication non-adherence from clinical variables were among the associated factors for AUD.

CONCLUSION

This review obtained a high average prevalence of AUD in tuberculosis patients and this varies across continents, design of studies, mean age of the participants, and assessment tool used. This implied the need for early screening and management of AUD in tuberculosis patients.

Predictive model of unfavorable outcomes for multidrug-resistant tuberculosis

OBJECTIVE

to analyze the temporal trend, identify the factors related and elaborate a predictive model for unfavorable treatment outcomes for multidrug-resistant tuberculosis (MDR-TB).

METHODS

Retrospective cohort study with all cases diagnosed with MDR-TB between the years 2006 and 2015 in the state of São Paulo. The data were collected from the state system of TB cases notifications (TB-WEB). The temporal trend analyzes of treatment outcomes was performed through the Prais-Winsten analysis. In order to verify the factors related to the unfavorable outcomes, abandonment, death with basic cause TB and treatment failure, the binary logistic regression was used. Pictorial representations of the factors related to treatment outcome and their prognostic capacity through the nomogram were elaborated.

RESULTS

Both abandonment and death have a constant temporal tendency, whereas the failure showed it as decreasing. Regarding the risk factors for such outcomes, using illicit drugs doubled the odds for abandonment and death. Besides that, being diagnosed in emergency units or during hospitalizations was a risk factor for death. On the contrary, having previous multidrug-resistant treatments reduced the odds for the analyzed outcomes by 33%. The nomogram presented a predictive model with 65% accuracy for dropouts, 70% for deaths and 80% for failure.

CONCLUSIONS

The modification of the current model of care is an essential factor for the prevention of unfavorable outcomes. Through predictive models, as presented in this study, it is possible to develop patient-centered actions, considering their risk factors and increasing the chances for cure.

Predictors of mortality in multidrug-resistant tuberculosis patients from Brazilian reference centers, 2005 to 2012

Objectives

To determine the main predictors of death in multidrug-resistant (MDRTB) patients from Brazil.

Design

Retrospective cohort study, a survival analysis of patients treated between 2005 and 2012.

Results

Of 3802 individuals included in study, 64.7% were men, mean age was 39 (1–93) years, and 70.3% had bilateral pulmonary disease. Prevalence of human immunodeficiency virus (HIV) was 8.3%. There were 479 (12.6%) deaths. Median survival time was 1452 days (4 years). Factors associated with increased risk of death were age greater than or equal to 60 years (hazard rate [HR] = 1.6, confidence interval [CI] = 1.15–2.2), HIV co-infection (HR = 1.46; CI = 1.05–1.96), XDR resistance pattern (HR = 1.74, CI = 1.05–2.9), beginning of treatment after failure (HR = 1.72, CI = 1.27–2.32), drug abuse (HR = 1.64, CI = 1.22–2.2), resistance to ethambutol (HR = 1.30, CI = 1.06–1.6) or streptomycin (HR = 1.24, CI = 1.01–1.51). Mainly protective factors were presence of only pulmonary disease (HR = 0.57, CI = 0.35–0.92), moxifloxacin use (HR = 0.44, CI = 0.25–0.80), and levofloxacin use (HR = 0.75; CI = 0.60–0.94).

Conclusion

A more comprehensive approach is needed to manage MDRTB, addressing early diagnostic, improving adhesion, and comorbidities, mainly HIV infection and drug abuse. The latest generation quinolones have an important effect in improving survival in MDRTB.

Time to treatment for rifampicin-resistant tuberculosis: systematic review and meta-analysis

BACKGROUND

To reduce transmission and improve patient outcomes, rapid diagnosis and treatment of rifampicin-resistant tuberculosis (RR-TB) is required.

OBJECTIVE

To conduct a systematic review and meta-analysis assessing time to treatment for RR-TB and variability using diagnostic testing methods and treatment delivery approach.

DESIGN

Studies from 2000 to 2015 reporting time to second-line treatment initiation were selected from PubMed and published conference abstracts.

RESULTS

From 53 studies, 83 cohorts (13 034 patients) were included. Overall weighted mean time to treatment from specimen collection was 81 days (95%CI 70-91), and was shorter with ambulatory (57 days, 95%CI 40-74) than hospital-based treatment (86 days, 95%CI 71-102). Time to treatment was shorter with genotypic susceptibility testing (38 days, 95%CI 27-49) than phenotypic testing (108 days, 95%CI 98-117). The mean percentage of diagnosed patients initiating treatment was 76% (95%CI 70-83, range 25-100).

CONCLUSION

Time to second-line anti-tuberculosis treatment initiation is extremely variable across studies, and often unnecessarily long. Reduced delays are associated with genotypic testing and ambulatory treatment settings. Routine monitoring of the proportion of diagnosed patients initiating treatment and time to treatment are necessary to identify areas for intervention.

"When Treatment Is More Challenging than the Disease": A Qualitative Study of MDR-TB Patient Retention

Background

One-fifth of the patients on multidrug-resistant tuberculosis treatment at the Drug-Resistant-TB (DR-TB) Site in Gujarat are lost-to-follow-up(LFU).

Objective

To understand patients’ and providers' perspectives on reasons for LFU and their suggestions to improve retention-in-care.

Design

Qualitative study conducted between December 2013-March 2014, including in-depth interviews with LFU patients and DOT-providers, and a focus group discussion with DR-TB site supervisors. A thematic-network analysis approach was utilised.

Results

Three sub-themes emerged: (i) Struggle with prolonged treatment; (ii) Strive against stigma and toward support; (iii) Divergent perceptions and practices. Daily injections, pill burden, DOT, migratory work, social problems, prior TB treatment, and adverse drugs effects were reported as major barriers to treatment adherence and retention-in-care by patients and providers. Some providers felt that despite their best efforts, LFU patients remain. Patient movements between private practitioners and traditional healers further influenced LFU.

Conclusion

The study points to a need for repeated patient counselling and education, improved co-ordination between various tiers of providers engaged in DR-TB care, collaboration between the public, private and traditional practitioners, and promotion of social and economic support to help patients adhere to MDR-TB treatment and avoid LFU.

Psycho-Socio-Economic Issues Challenging Multidrug Resistant Tuberculosis Patients: A Systematic Review

Background

Limited treatment options, long duration of treatment and associated toxicity adversely impact the physical and mental well-being of multidrug-resistant tuberculosis (MDR-TB) patients. Despite research advances in the microbiological and clinical aspects of MDR-TB, research on the psychosocial context of MDR-TB is limited and less understood.

Methodology

We searched the databases of PubMed, MEDLINE, Embase and Google Scholar to retrieve all published articles. The final manuscripts included in the review were those with a primary focus on psychosocial issues of MDR-TB patients. These were assessed and the information was thematically extracted on the study objective, methodology used, key findings, and their implications. Intervention studies were evaluated using components of the methodological and quality rating scale. Due to the limited number of studies and the multiple methodologies employed in the observational studies, we summarized these studies using a narrative approach, rather than conducting a formal meta-analysis. We used ‘thematic synthesis’ method for extracting qualitative evidences and systematically organised to broader descriptive themes.

Results

A total of 282 published articles were retrieved, of which 15 articles were chosen for full text review based on the inclusion criteria. Six were qualitative studies; one was a mixed methods study; and eight were quantitative studies. The included studies were divided into the following issues affecting MDR-TB patients: a) psychological issues b) social issues and economic issues c) psychosocial interventions. It was found that all studies have documented range of psychosocial and economic challenges experienced by MDR-TB patients. Depression, stigma, discrimination, side effects of the drugs causing psychological distress, and the financial constraints due to MDR-TB were some of the common issues reported in the studies. There were few intervention studies which addressed these psychosocial issues most of which were small pilot studies. There is dearth of large scale randomized psychosocial intervention studies that can be scaled up to strengthen management of MDR-TB patients which is crucial for the TB control programme.

Conclusion

This review has captured the psychosocial and economic issues challenging MDR patients. However there is urgent need for feasible, innovative psychosocial and economic intervention studies that help to equip MDR-TB patients cope with their illness, improve treatment adherence, treatment outcomes and the overall quality of life of MDR-TB patients.

Treatment outcome among cases of multidrug-resistant tuberculosis (MDR TB) in Western India: A prospective study

Multidrug-resistant TB has become a significant public health problem in a number of countries and an obstacle to effective TB control. Therefore, the present study sought to determine the treatment outcome in patients with MDR TB in seven districts and to examine the factors affecting the treatment outcome. A prospective cohort study was carried out by enrolling all the registered patients in DOTs Plus center of Vadodara district from February 2010 to December 2010. A total of 142 patients were interviewed using a pre-tested semi-structured questionnaire at the DOTS centers of seven districts of Gujarat or at their homes in cases of defaulters/death. After 24 months, of those 145 patients, 48 (33.10%) were declared cured, 8 (5.50%) had completed their treatment, 43 (29.70%) patients died during the treatment, and 32 (21.10%) patients defaulted during treatment. Factors associated with a significant difference in the outcomes were income, marital status, and education. Only education significantly affected treatment outcome upon applying logistic regression. Therefore, proper counseling on drug adherence should be applied at the programmatic level.

Multidrug-Resistant Tuberculosis Treatment Outcomes in Relation to Treatment and Initial Versus Acquired Second-Line Drug Resistance

BACKGROUND

Resistance to second-line drugs develops during treatment of multidrug-resistant (MDR) tuberculosis, but the impact on treatment outcome has not been determined.

METHODS

Patients with MDR tuberculosis starting second-line drug treatment were enrolled in a prospective cohort study. Sputum cultures were analyzed at a central reference laboratory. We compared subjects with successful and poor treatment outcomes in terms of (1) initial and acquired resistance to fluoroquinolones and second-line injectable drugs (SLIs) and (2) treatment regimens.

RESULTS

Of 1244 patients with MDR tuberculosis, 973 (78.2%) had known outcomes and 232 (18.6%) were lost to follow-up. Among those with known outcomes, treatment succeeded in 85.8% with plain MDR tuberculosis, 69.7% with initial resistance to either a fluoroquinolone or an SLI, 37.5% with acquired resistance to a fluoroquinolone or SLI, 29.3% with initial and 13.0% with acquired extensively drug-resistant tuberculosis (P < .001 for trend). In contrast, among those with known outcomes, treatment success increased stepwise from 41.6% to 92.3% as the number of drugs proven effective increased from ≤1 to ≥5 (P < .001 for trend), while acquired drug resistance decreased from 12% to 16% range, depending on the drug, down to 0%-2% (P < .001 for trend). In multivariable analysis, the adjusted odds of treatment success decreased 0.62-fold (95% confidence interval, .56-.69) for each increment in drug resistance and increased 2.1-fold (1.40-3.18) for each additional effective drug, controlling for differences between programs and patients. Specific treatment, patient, and program variables were also associated with treatment outcome.

CONCLUSIONS

Increasing drug resistance was associated in a logical stepwise manner with poor treatment outcomes. Acquired resistance was worse than initial resistance to the same drugs. Increasing numbers of effective drugs, specific drugs, and specific program characteristics were associated with better outcomes and less acquired resistance.

Loss-To-Follow-Up on Multidrug Resistant Tuberculosis Treatment in Gujarat, India: The WHEN and WHO of It

Background

Multidrug-resistant Tuberculosis (MDR-TB) is a rising global threat to public health and concerted efforts for its treatment are diluted if the outcomes are not successful, loss to follow up (LFU) being one of them. It is therefore necessary to know the proportion and the associated reasons for LFU and devise effective patient-centered strategies to improve retention in care.

Methods

A retrospective cohort study was conducted at the MDR-TB treatment site (DR-TB Site)in Central Gujarat among all patients registered from February 2010 to June 2013.LFU patients were defined as those whose treatment was interrupted for two or more consecutive months for any reason. Descriptive statistics, survival analysis and multivariate modeling were used to determine the proportion of patients LFU and to assess associations between LFU and selected demographic and clinical factors.

Results

A total of 796 patients were enrolled during the study period; 71.9% were male and the median age was 35 years [Interquartile range (IQR) 27-45].The overall proportion of LFU patients was 153/796 (19.2%).The majority of LFU patients (133/153 i.e.87%) were lost within the first 6 months of treatment. Ambulatory treatment initiation (adjusted Hazards ratio aHR=2.63, CI:1.01-6.86), different providers in IP and CP ( aHR=1.27, CI:1.18-1.38)and culture conversion after more than 4 months of treatment(aHR=1.34, CI: 1.21-1.49)were found to be significantly associated with LFU in multivariate models.

Conclusions

A high proportion of LFU among patients on MDR-TB treatment was found in a programmatic setting in India. Clinical but equally important programmatic factors were associated with LFU, accounting for one-fifth of all the outcomes of MDR-TB treatment. Proper training for DOT providers and aggressive counseling and health system strengthening with patient friendly follow up services may help reduce LFU.

Safety and Efficacy of Delamanid in the Treatment of Multidrug-Resistant Tuberculosis (MDR-TB)

Globally, the incidence of tuberculosis (TB) is declining but the proportion of drug-resistant cases has increased. Strains resistant to both isoniazid and rifampin, and possibly other antibiotics, called multidrug-resistant (MDR), are particularly difficult to treat. Poorer outcomes, including increased mortality, occur in patients infected with MDR strains and the costs associated with treatment of MDR-TB are substantially greater. The recent recognition of MDR-TB and strains with more complex resistance patterns has stimulated the development of new TB medications including fluoroquinolones, oxazolidinones, diarylquinolines, nitroimidazopyrans, ethylenediamines, and benzothiazinones. Bedaquiline, a diarylquinoline, was approved for the treatment of MDR-TB in 2012. Addition of delamanid to WHO-approved treatment improved outcomes for MDR-TB and for extensively drug-resistant TB in a large randomized, controlled phase II clinical trial and is undergoing evaluation in a large international phase III study. This review will focus on MDR-TB and the role of delamanid in its treatment.

Aggressive regimens for multidrug-resistant tuberculosis reduce recurrence

BACKGROUND

Recurrent tuberculosis disease occurs within 2 years in as few as 1% and as many as 29% of individuals successfully treated for multidrug-resistant (MDR) tuberculosis. A better understanding of treatment-related factors associated with an elevated risk of recurrent tuberculosis after cure is urgently needed to optimize MDR tuberculosis therapy.

METHODS

We conducted a retrospective cohort study among adults successfully treated for MDR tuberculosis in Peru. We used multivariable Cox proportional hazards regression analysis to examine whether receipt of an aggressive MDR tuberculosis regimen for ≥18 months following sputum conversion from positive to negative was associated with a reduced rate of recurrent tuberculosis.

RESULTS

Among 402 patients, the median duration of follow-up was 40.5 months (interquartile range, 21.2-53.4). Receipt of an aggressive MDR tuberculosis regimen for ≥18 months following sputum conversion was associated with a lower risk of recurrent tuberculosis (hazard ratio, 0.40 [95% confidence interval, 0.17-0.96]; P = .04). A baseline diagnosis of diabetes mellitus also predicted recurrent tuberculosis (hazard ratio, 10.47 [95% confidence interval, 2.17-50.60]; P = .004).

CONCLUSIONS

Individuals who received an aggressive MDR tuberculosis regimen for ≥18 months following sputum conversion experienced a lower rate of recurrence after cure. Efforts to ensure that an aggressive regimen is accessible to all patients with MDR tuberculosis, such as minimization of sequential ineffective regimens, expanded drug access, and development of new MDR tuberculosis compounds, are critical to reducing tuberculosis recurrence in this population. Patients with diabetes mellitus should be carefully managed during initial treatment and followed closely for recurrent disease.