Treatment outcomes among drug-susceptible tuberculosis patients in Latvia, 2006-2010

Is Tobacco Use Associated With Risk of Recurrence and Mortality Among People With TB?: A Systematic Review and Meta-Analysis

BACKGROUND

Associations between tobacco use and poor TB treatment outcomes are well documented. However, for important outcomes such as TB recurrence or relapse and mortality during treatment, as well as for associations with smokeless tobacco (ST), the evidence is not summarized systematically.

RESEARCH QUESTION

Is tobacco use associated with risk of poor treatment outcomes among people with TB?

STUDY DESIGN AND METHODS

The MEDLINE, Embase, and Cumulative Index of Nursing and Allied Health Literature databases were searched on November 22, 2021. Epidemiologic studies reporting associations between tobacco use and at least one TB treatment outcome were eligible. Independent double-screening, extractions, and quality assessments were undertaken. Random effects meta-analyses were conducted for the two primary review outcomes (TB recurrence or relapse and mortality during treatment), and heterogeneity was explored using subgroups. Other outcomes were synthesized narratively.

RESULTS

Our searches identified 1,249 records, of which 28 were included in the meta-analyses. Based on 15 studies, higher risk of TB recurrence or relapse was found with ever using tobacco vs never using tobacco (risk ratio [RR], 1.78; 95% CI, 1.31-2.43; I2 = 85%), current tobacco use vs no tobacco use (RR, 1.95; 95% CI, 1.59-2.40; I2 = 72%), and former tobacco use vs never using tobacco (RR, 1.84; 95% CI, 1.21-2.80; I2 = 4%); heterogeneity arose from differences in study quality, design, and participant characteristics. Thirty-eight studies were identified for mortality, of which 13 reported mortality during treatment. Ever tobacco use (RR, 1.55; 95% CI, 1.32-1.81; I2 = 0%) and current tobacco use (RR, 1.51; 95% CI, 1.09-2.10; I2 = 87%) significantly increased the likelihood of mortality during treatment among people with TB compared with never using tobacco and not currently using tobacco, respectively; heterogeneity was explained largely by differences in study design. Almost all studies in the meta-analyses scored high or moderate on quality assessments. Narrative synthesis showed that tobacco use was a risk factor for other unfavorable TB treatment outcomes, as previously documented. Evidence on ST was limited, but identified studies suggested an increased risk for poor outcomes with its use compared with not using it.

INTERPRETATION

Tobacco use significantly increases the risk of TB recurrence or relapse and mortality during treatment among people with TB, highlighting the need to address tobacco use to improve TB outcomes.

TRIAL REGISTRY

PROSPERO; No.: CRD42017060821; URL: https://www.crd.york.ac.uk/prospero/.

Hidden loss to follow-up among tuberculosis patients managed by public-private mix institutions in South Korea

In South Korea, public-private mix (PPM) was launched in 2011. This retrospective cohort study sought to determine the rate of loss to follow-up (LTFU) among drug-susceptible tuberculosis (DS-TB) patients in all nationwide PPM institutions, and the risk factors for LTFU. National notification data for DS-TB patients diagnosed between August 2011 and July 2014 in PPM institutions were analysed. Determination of LTFU included detection of instances where patients were transferred out, but when they did not attend at other TB centres in the following two months. Univariable and multivariable competing risk models were used to determine risk factors for LTFU. 73,046 patients with 78,485 records were enrolled. Nominally, 3426 (4.4%) of records were LTFU. However, after linking the multiple records in each patient, the percentage of LTFU was 12.3% (9004/73,046). Risk factors for LTFU were: being foreign-born (3.13 (95% CI 2.77-3.53)), prior LTFU (2.31 (2.06-2.59)) and greater distance between the patient's home and the TB centre (4.27 (4.03-4.53)). 'Transfer-out' was a risk factor in patients managed by treatment centres close to home (1.65 (1.49-1.83)), but protective for those attending centres further (0.77 (0.66-0.89)) or far-away (0.52 (0.46-0.59)) from home. By considering the complete picture of a patient's interactions with healthcare, we identified a much higher level of LTFU than previously documented. This has implications for how outcomes of treatment are reported and argues for a joined-up national approach for the management and surveillance of TB patients, in nations with similar healthcare systems.

The impact of smoking on tuberculosis treatment outcomes: a meta-analysis

BACKGROUND: Cigarette smoking contributes to tuberculosis (TB) epidemiology. However, limited evidence exists on how smoking impacts TB treatment outcomes such as treatment loss to follow-up and culture conversion.METHODS: This meta-analysis assessed current evidence of the impact of active cigarette smoking on TB treatment outcomes. PubMed, Scopus, Embase, and the Cochrane Library were searched for English-language articles published from database inception through 2017. Articles addressing active pulmonary TB and cigarette smoking were identified and data abstracted. Smokers were defined as those who smoked every day or some days at the time of interview/diagnosis. Non-smokers did not smoke at the time of interview/diagnosis. Unfavorable outcomes included any outcome other than cure or completion of TB treatment. Three different data sets were examined: 8 articles addressing unfavorable treatment outcomes, 9 analyzing only treatment loss to follow-up, and 5 addressing delayed smear or culture conversion. Studies that had <20 subjects or that addressed only populations with comorbidities were excluded.RESULTS: We identified 1030 studies; 21 studies fulfilled the inclusion/exclusion criteria. Smokers had greater odds of unfavorable outcomes (pooled odds ratio [pOR] 1.23, 95%CI 1.14-1.33), delayed smear or culture conversion (pOR 1.55, 95%CI 1.04-2.07), and treatment loss to follow-up (pOR 1.35, 95%CI 1.21-1.50).CONCLUSION: Cigarette smoking is associated with negative treatment results and delayed conversion to negative smear or culture, suggesting smoking is an important factor for consideration in TB elimination efforts.

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.

Trends and risk factors for death and excess all-cause mortality among notified tuberculosis patients in the UK: an analysis of surveillance data

Introduction

In the UK, several hundred patients notified with tuberculosis (TB) die every year. The aim of this article is to describe trends in deaths among notified TB patients, explore risk factors associated with death and compare all-cause mortality in TB patients with age-specific mortality rates in the general UK population.

Methods

We used 2001–2014 data from UK national TB surveillance to explore trends and risk factors for death, and population mortality data to compare age-specific death rates among notified TB patients with annual death rates in the UK general population.

Results

The proportion of TB patients in the UK who died each year declined steadily from 7.1% in 2002 to 5.5% in 2014. One in five patients (21.3%) was diagnosed with TB post-mortem. Where information was available, almost half of the deaths occurred within 2 months of starting treatment. Risk factors for death included demographic, disease-specific and social risk factors. Age had by far the largest effect, with patients aged ≥80 years having a 70 times increased risk of death compared with those aged <15 years. In contrast, excess mortality determined by incidence ratios comparing all-cause mortality among TB patients with that of the general population was highest among children and the working-age population (15–64 years old).

Conclusions

Efforts to control TB and improve diagnosis and treatment outcomes in the UK need to be sustained. Control efforts need to focus on socially deprived and vulnerable groups. There is a need for further in-depth analysis of deaths of TB patients in the UK to identify potentially preventable factors.

Despite an overall decline in death among TB patients in the UK, patients with TB are still 6 times more likely to die during follow-up than the annual death rate in the general populationhttp://bit.ly/2MqDw9Q

A retrospective analysis of treatment outcomes of drug-susceptible TB in Kazakhstan, 2013-2016

Kazakhstan has a high burden of multidrug-resistant tuberculosis (TB). The patient-centered National Program for the treatment and prevention of TB has been implemented in Kazakhstan. The program is aimed at meeting the needs of patients and expansion of the outpatient treatment of TB in the country.The aim of the study was to compare the efficacy of the outpatient and inpatient treatment of drug-susceptible TB.This study was a retrospective cohort study.A total of 36.926 TB cases were included. The majority of patients were treated as inpatients. The socioeconomic factors, sex, age, HIV status, and other diagnostic factors (e.g., sputum smear results, extrapulmonary disease) may serve as risk factors to estimate the likely TB treatment outcome. The outpatient treatment of drug-susceptible TB seems to be a comparable option to the inpatient treatment in terms of efficacy.The socioeconomic factors are the main modifiable risk factors for treatment failure. The outpatient treatment of drug-susceptible TB is safe and effective.

Treatment efficacy of drug-resistant tuberculosis in Bashkortostan, Russia: A retrospective cohort study

BACKGROUND

Russia, together with other former Soviet Union countries, is characterized by one of the highest burdens of drug-resistant tuberculosis. Published data on the drug-resistant tuberculosis for these countries are limited, and it is not clear whether current treatment regimens remain effective against constantly evolving drug-resistant strains.

OBJECTIVES

The aim of the study was to evaluate treatment efficacy of patients with multidrug-resistant (MDR), extensively drug-resistant (XDR) and drug-susceptible (DSTB) tuberculosis in the most populous region of Russia (Bashkortostan) that borders with Central Asia.

METHODS

A retrospective cohort study was performed on 436 patients with pulmonary tuberculosis who were enrolled between January 1, 2016, and February 28, 2018, and received treatment according to WHO recommendations. Altogether, 369 patients completed the full course of chemotherapy. Clinical characteristics and treatment outcomes of DSTB, MDR, and XDR-TB patients were analyzed.

RESULTS

Of 436 patients, 169 (39%) had XDR-TB, 94 (22%) had MDR-TB and 173 (40%) had DSTB. Half of the MDR-TB patients (44%) and 82% of XDR-TB patients failed treatment. Patients with DSTB had unexpectedly poor treatment efficacy: only 67% had treatment success. We found that most of the MDR isolates from our patients were resistant to all first-line drugs, and a majority of the XDR isolates were resistant to more than 6-7 anti-TB drugs. While this can explain poor treatment efficacy in drug-resistant cases, causes of poor treatment efficacy in DSTB patients remain unclear. Finally, a considerable fraction (46%) of newly diagnosed patients had MDR-TB (27%) and XDR-TB (19%), suggesting that drug-resistant Mtb is being transmitted in the general population. To our best knowledge, this study is the first one to report XDR-TB prevalence in Russia in recent years (2016-2018).

CONCLUSIONS

MDR and XDR-TB became more common in recent years and treatment efficacy is declining at the face of more extensive drug resistance. There is evidence for the transmission of resistant strains in the general population, which calls for urgent changes not only in clinical practice but also in measures to prevent spread in the general population.

Areas with evidence of equity and their progress on mortality from tuberculosis in an endemic municipality of southeast Brazil

Background

In Brazil, people still fall ill and die from tuberculosis (TB), and this can be explained by the significant impasse in the equity of distribution of therapeutic resources to the population as a whole. The aim was to identify geographical areas which have shown progress in terms of equity (of income, schooling and urban occupancy) and test its effect on mortality from TB in a municipality of southeast Brazil.

Methods

It is an ecological study considering TB as the basic cause for deaths registered between 2006 and 2013 on the Mortality Information System and other variables obtained through the Demographic Census of the Brazilian Institute of Geography and Statistics (2010). The geographical area for analysis comprised the areas of coverage of the health services. Social indicators have been constructed through the Principal Component Analysis (PCA). The cases were geocoded and the annual mortality rate from TB was calculated with smoothing using the local empirical Bayesian method. Multiple linear regression was then performed. There was confirmation of the existence of spatial dependence of residue through the application of the Global Moran I test, and application of the Models with Global Spatial Effects, to identify the best standard of spatial regression.

Results

The mortality rates ranged from 0.00 to 2.8 deaths per 100,000 people, per year. In the PCA, three indicators were constructed, and designated as indicators of income, social inequality, and social equity. In multiple linear regression, the indicator of social equity was statistically significant (P < 0.0001) but had a negative association, an adjusted R² of 28.36% and with spatial dependence (Moran I = 0.21, P = 0.003455). The best model to deal with existing spatial dependence was the Spatial Lag Model.

Conclusions

The better social conditions have shown progress in reducing mortality from TB, thereby reinforcing the achievement of Sustainable Development Goals. In addition, cartography was also applied, which can be replicated in other scenarios throughout the world, using a scope distinct from that of works traditionally produced in that it places the emphasis on social equity.

Electronic supplementary material

The online version of this article (doi:10.1186/s40249-017-0348-5) contains supplementary material, which is available to authorized users.

Predicting treatment failure, death and drug resistance using a computed risk score among newly diagnosed TB patients in Tamaulipas, Mexico

The purpose of this study was to develop a method for identifying newly diagnosed tuberculosis (TB) patients at risk for TB adverse events in Tamaulipas, Mexico. Surveillance data between 2006 and 2013 (8431 subjects) was used to develop risk scores based on predictive modelling. The final models revealed that TB patients failing their treatment regimen were more likely to have at most a primary school education, multi-drug resistance (MDR)-TB, and few to moderate bacilli on acid-fast bacilli smear. TB patients who died were more likely to be older males with MDR-TB, HIV, malnutrition, and reporting excessive alcohol use. Modified risk scores were developed with strong predictability for treatment failure and death (c-statistic 0·65 and 0·70, respectively), and moderate predictability for drug resistance (c-statistic 0·57). Among TB patients with diabetes, risk scores showed moderate predictability for death (c-statistic 0·68). Our findings suggest that in the clinical setting, the use of our risk scores for TB treatment failure or death will help identify these individuals for tailored management to prevent these adverse events. In contrast, the available variables in the TB surveillance dataset are not robust predictors of drug resistance, indicating the need for prompt testing at time of diagnosis.

Addressing tuberculosis control in fragile states: Urban DOTS experience in Kabul, Afghanistan, 2009-2015

Tuberculosis (TB) is a major public health problem in Afghanistan, but experience in implementing effective strategies to prevent and control TB in urban areas and conflict zones is limited. This study shares programmatic experience in implementing DOTS in the large city of Kabul. We analyzed data from the 2009–2015 reports of the National TB Program (NTP) for Kabul City and calculated treatment outcomes and progress in case notification using rates, ratios, and confidence interval. Urban DOTS was implemented by the NTP in partnership with United States Agency for International Development (USAID)-funded TB projects, the World Health Organization (WHO), and the private sector. Between 2009 and 2015, the number of DOTS-providing centers in Kabul increased from 22 to 85. In total, 24,619 TB patients were enrolled in TB treatment during this period. The case notification rate for all forms of TB increased from 59 per 100,000 population to 125 per 100,000. The case notification rate per 100,000 population for sputum-smear-positive TB increased from 25 to 33. The treatment success rate for all forms of TB increased from 31% to 67% and from 47% to 77% for sputum-smear-positive TB cases. The treatment success rate for private health facilities increased from 52% in 2010 to 80% in 2015. In 2013, contact screening was introduced, and the TB yield was 723 per 100,000—more than two times higher than the estimated national prevalence of 340 per 100,000. Contact screening contributed to identifying 2,509 child contacts of people with TB, and 76% of those children received isoniazid preventive therapy. The comprehensive urban DOTS program significantly improved service accessibility, TB case finding, and treatment outcomes in Kabul. Public- and private-sector involvement also improved treatment outcomes; however, the treatment success rate remains higher in private health facilities. While the treatment success rate increased significantly, it remains lower than the national average, and more efforts are needed to improve treatment outcomes in Kabul. We recommend that the urban DOTS approach be replicated in other countries and cities in Afghanistan with settings similar to Kabul.

Survival of patients with multidrug-resistant TB in Eastern Europe: what makes a difference?

BACKGROUND

The quality of care for patients with TB in Eastern Europe has improved significantly; nevertheless drug resistance rates remain high. We analysed survival in a cohort of patients with multidrug-resistant and extensively drug-resistant (MDR-/XDR-) TB from Latvia, Lithuania, Estonia and Bucharest city.

METHODS

Consecutive adult new and retreatment patients with culture-confirmed pulmonary MDR-TB registered for treatment in 2009 (and in 2007 in Latvia) were enrolled; prospective survival information was collected.

RESULTS

A total of 737 patients were included into the cohort. Of all MDR-TB cases, 46% were newly diagnosed; 56% of all MDR-TB cases had no additional resistance to fluoroquinolones or injectable agents, 33% had pre-XDR-TB and 11% XDR-TB. Median survival was 5.9 years in patients with MDR-TB and XDR-TB; 1.9 years in patients coinfected with HIV. Older age, male gender, alcohol abuse, retirement, co-morbidities, extrapulmonary involvement and HIV coinfection independently worsened survival. Inclusion of fluoroquinolones and injectable agents improves survival in patients with MDR-TB. Pre-XDR and XDR status did not significantly shorten survival as long as fluoroquinolones and injectable agents were part of the regimen. Moxifloxacin seems to improve survival in ofloxacin-susceptible patients when compared with older generation fluoroquinolones.

CONCLUSIONS

The burden of additional resistances in patients with MDR-TB is high likely due to primary transmission of resistant strains. Social and programmatic factors including management of alcohol dependency, expansion of HIV testing and antiretroviral treatment need to be addressed in order to achieve cure and to interrupt transmission. The role of last generation fluoroquinolones and injectable agents in treatment of patients with pre-XDR and XDR-TB needs to be further investigated.

Resistance profile and risk factors of drug resistant tuberculosis in the Baltic countries

The rates of multi- and extensively drug-resistant tuberculosis (X/MDRTB) in the Baltic countries are the highest within the European Union hampering recent achievements of national TB control programmes. We included all consecutive culture-confirmed X/MDRTB patients registered for treatment in 2009 in Latvia, Lithuania and Estonia into this multicenter case-control study. Cases were compared with randomly selected controls with non-MDRTB registered for treatment in the same year across these sites. Of 495 MDRTB patients, 243 (49.7%) showed resistance to at least one second-line drug, 206 (42.1%) had pre-XDRTB (i.e. MDRTB with additional resistance to a second-line injectable or fluoroquinolones) and 64 (13.1%) had XDRTB. Younger age, male gender and known contact with an MDRTB case were associated with increased risk of primary infection with X/MDRTB strains. Previous treatment and alcohol abuse were strong predictors for MDRTB acquisition; defaults and failures in the past triggered XDRTB development. All patients received appropriate therapy; less than half of the patients were fully adherent. An erroneous treatment strategy is unlikely to drive resistance development. Increasing patients' compliance, addressing issues of social support, rapid detection of drug resistance and improving infection control is crucial for prevention of further spread of X/MDRTB and achieving higher cure rates.