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

Effectiveness and safety of modified fully oral 9-month treatment regimens for rifampicin-resistant tuberculosis: a prospective cohort study

BACKGROUND

In 2020, WHO guidelines prioritised the use of a standard fully oral short treatment regimen (STR) consisting of bedaquiline, levofloxacin or moxifloxacin, ethionamide, ethambutol, high-dose isoniazid, pyrazinamide, and clofazimine for the management of rifampicin-resistant tuberculosis. A high prevalence of resistance to constituent drugs precluded its widespread use by countries in the WHO European region. We evaluated three 9-month fully oral modified STRs (mSTRs) in which ethionamide, ethambutol, isoniazid, and pyrazinamide were replaced by linezolid, cycloserine, or delamanid (or a combination).

METHODS

This multicountry, prospective, single-arm, cohort study examined the effectiveness and safety of mSTRs for fluoroquinolone-susceptible, rifampicin-resistant pulmonary tuberculosis in 13 countries in the WHO European region during 2020-23. We enrolled adults and children of all ages with bacteriologically confirmed rifampicin-resistant, fluoroquinolone-susceptible pulmonary tuberculosis, and children (aged 0-18 years) with clinically diagnosed disease and a confirmed contact with rifampicin-resistant, fluoroquinolone-susceptible tuberculosis. Participants aged 6 years or older received one of two regimens: bedaquiline, linezolid, levofloxacin, clofazimine, and cycloserine; or bedaquiline, linezolid, levofloxacin, clofazimine, and delamanid. Children younger than 6 years received delamanid, linezolid, levofloxacin, and clofazimine. Participants were followed up for 12 months after successful treatment completion to detect recurrence and death. The primary outcome was the cumulative probability of not having an unsuccessful study outcome (defined as treatment failure, on-treatment loss to follow-up, death, or recurrence) before 22 months of study follow-up. The primary safety outcome was the incidence of each adverse event of interest (peripheral neuropathy, optic neuritis, myelosuppression, hepatitis, prolonged QT interval, hypokalaemia, and acute kidney injury) of grade 3 or higher severity during the treatment course.

FINDINGS

Between Aug 28, 2020 and May 26, 2021, 7272 patients were screened and 2636 were included in the treatment cohort. 1966 (74·6%) were male, 670 (25·4%) were female, and median age was 43 years (IQR 33-53). Treatment success was recorded for 2181 (82·7%) participants. The cumulative probability of not having an unsuccessful study outcome 22 months after treatment initiation was 79% (95% CI 78-81). Increasing age (adjusted hazard ratio 2·61 [95% CI 1·70-4·04] for people aged >64 years vs 35-44 years), HIV-positive status (1·53 [1·16-2·01]), presence of bilateral cavities (1·68 [1·29-2·19]), smoking history (1·34 [1·05-1·71]), baseline anaemia (1·46 [1·15-1·86]), unemployment (1·37 [1·04-1·80]), elevated baseline liver enzymes (1·40 [1·13-1·73]), and excessive alcohol use (1·47 [1·14-1·89]) were positively associated with unsuccessful study outcomes. In the safety cohort of 2813 participants who received at least one dose, 301 adverse events of interest were recorded in 252 (9·0%) participants with the most frequent being myelosuppression (139 [4·9%] participants, 157 [52·2%] events).

INTERPRETATION

The high treatment success and good safety results indicate considerable potential for the use of mSTRs in programmatic conditions, especially for individuals not eligible for the current WHO-recommended 6-month regimen and in settings with a need for alternative options.

FUNDING

The Global Fund to Fight AIDS, Tuberculosis and Malaria; United States Agency for International Development; Government of Germany; and WHO.

TRANSLATION

For the Russian translation of the abstract see Supplementary Materials section.

Revisiting the association between vitamin D deficiency and active tuberculosis: A prospective case-control study in Taiwan

BACKGROUND

To revisit the association between vitamin D deficiency (VDD, defined as serum 25(OH)D < 20 ng/ml) and incident active tuberculosis (TB), after two potentially underpowered randomized trials showed statistically non-significant 13%-22% decrease in TB incidence in vitamin D supplementation groups.

METHODS

We prospectively conducted an age/sex-matched case-control study that accounting for body-mass index (BMI), smoking, and other confounding factors to examine the association between VDD and active TB among non-HIV people in Taiwan (latitude 24°N), a high-income society which continues to have moderate TB burden.

RESULTS

We enrolled 62 people with incident active TB and 248 people in control group. The TB case patients had a significantly higher proportion of VDD compared to the control group (51.6% vs 29.8%, p = 0.001). The 25(OH)D level was also significantly lower in TB patients compared to control group (21.25 ± 8.93 ng/ml vs 24.45 ± 8.36 ng/ml, p = 0.008). In multivariable analysis, VDD (adjusted odds ratio [aOR]: 3.03, p = 0.002), lower BMI (aOR: 0.81, p < 0.001), liver cirrhosis (aOR: 8.99, p = 0.042), and smoking (aOR: 4.52, p = 0.001) were independent risk factors for incident active TB.

CONCLUSIONS

VDD is an independent risk factor for incident active TB. Future randomized trials examining the effect of vitamin D supplementation on TB incidence should focus on people with a low BMI or other risk factors to maximize the statistical power.

Cigarette Smoking as a Risk Factor for Tuberculosis in Adults: Epidemiology and Aspects of Disease Pathogenesis

It has been noted by the World Health Organisation that cases of tuberculosis in 2022 globally numbered 10.6 million, resulting in 1.3 million deaths, such that TB is one of the infectious diseases causing the greatest morbidity and mortality worldwide. Since as early as 1918, there has been an ongoing debate as to the relationship between cigarette smoking and TB. However, numerous epidemiological studies, as well as meta-analyses, have indicated that both active and passive smoking are independent risk factors for TB infection, development of reactivation TB, progression of primary TB, increased severity of cavitary disease, and death from TB, among several other considerations. With this considerable body of evidence confirming the association between smoking and TB, it is not surprising that TB control programmes represent a key potential preventative intervention. In addition to coverage of the epidemiology of TB and its compelling causative link with smoking, the current review is also focused on evidence derived from clinical- and laboratory-based studies of disease pathogenesis, most prominently the protective anti-mycobacterial mechanisms of the alveolar macrophage, the primary intracellular refuge of M. tuberculosis. This section of the review is followed by an overview of the major strategies utilised by the pathogen to subvert these antimicrobial mechanisms in the airway, which are intensified by the suppressive effects of smoke inhalation on alveolar macrophage function. Finally, consideration is given to a somewhat under-explored, pro-infective activity of cigarette smoking, namely augmentation of antibiotic resistance due to direct effects of smoke per se on the pathogen. These include biofilm formation, induction of cellular efflux pumps, which eliminate both smoke-derived toxicants and antibiotics, as well as gene modifications that underpin antibiotic resistance.

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/.

Cigarette smoking and risk of severe infectious respiratory diseases in UK adults: 12-year follow-up of UK biobank

BACKGROUND

The relevance of tobacco smoking for infectious respiratory diseases (IRD) is uncertain. We investigated the associations of cigarette smoking with severe IRD resulting in hospitalization or death in UK adults.

METHODS

We conducted a prospective study of cigarette smoking and risk of severe IRD in UK Biobank. The outcomes included pneumonia, other acute lower respiratory tract infections (OA-LRTI) and influenza. Multivariable Cox regression analyses were used to estimate hazard ratios (HRs) of severe IRD associated with smoking habits after adjusting for confounding factors.

RESULTS

Among 341 352 participants with no prior history of major chronic diseases, there were 12 384 incident cases with pneumonia, 7054 with OA-LRTI and 795 with influenza during a 12-year follow-up. Compared with non-smokers, current smoking was associated with ⁓2-fold higher rates of severe IRD (HR 2.40 [2.27-2.53] for pneumonia, 1.99 [1.84-2.14] for OA-LRTI and 1.82 [95% confidence interval: 1.47-2.24] for influenza). Incidence of all severe IRDs were positively associated with amount of cigarettes smoked. The HRs for each IRD (except influenza) also declined with increasing duration since quitting.

CONCLUSIONS

Current cigarette smoking was positively associated with higher rates of IRD and the findings extend indications for tobacco control measures and vaccination of current smokers for prevention of severe IRD.

Do patients attempt and succeed in quitting smoking during tuberculosis treatment? A prospective cohort study

BACKGROUND

Despite a well-known relation between smoking tobacco and the tuberculosis epidemic, the factors associated with smoking cessation in tuberculosis patients are unclear. This study aims to examine the cascade of smoking cessation and the factors associated with persistent smoking among tuberculosis patients.

METHODS

We conducted a prospective cohort study enrolling adult patients with pulmonary tuberculosis between 2016 and 2019 in the Republic of Korea. We examined the smoking status at baseline, followed the current smokers, re-examined their smoking status after 6 months of anti-tuberculosis treatment, and identified the factors associated with persistent smoking.

RESULTS

Of the 419 enrolled patients, 109 (26.0%) were current smokers at baseline. Of the 79 current smokers who completed the 6-month survey, 24 (30.4%) succeeded in quitting smoking after 6 months of treatment. The adjusted odds ratio for persistent smoking was 6.57 (95% confidence interval [CI], 1.76-27.83) for drinking and 0.15 (95% CI, 0.03-0.68) for diabetes comorbidity.

CONCLUSION

Drinking alcohol and diabetes comorbidity were important factors in smoking cessation. Only one third of the tuberculosis patients in our study cohort succeeded in quitting smoking during the 6-month treatment period. More aggressive interventions for smoking cessation should be adopted within the national anti-tuberculosis program.

Ex vivo and in vivo evidence that cigarette smoke-exposed T regulatory cells impair host immunity against Mycobacterium tuberculosis

Introduction

A strong epidemiologic link exists between cigarette smoke (CS) exposure and susceptibility to tuberculosis (TB). Macrophage and murine studies showed that CS and nicotine impair host-protective immune cells against Mycobacterium tuberculosis (MTB) infection. While CS and nicotine may activate T regulatory cells (Tregs), little is known about how CS may affect these immunosuppressive cells with MTB infection.

Methods

We investigated whether CS-exposed Tregs could exacerbate MTB infection in co-culture with human macrophages and in recipient mice that underwent adoptive transfer of Tregs from donor CS-exposed mice.

Results

We found that exposure of primary human Tregs to CS extract impaired the ability of unexposed human macrophages to control an MTB infection by inhibiting phagosome-lysosome fusion and autophagosome formation. Neutralizing CTLA-4 on the CS extract-exposed Tregs abrogated the impaired control of MTB infection in the macrophage and Treg co-cultures. In Foxp3+GFP+DTR+ (Thy1.2) mice depleted of endogenous Tregs, adoptive transfer of Tregs from donor CS-exposed B6.PL(Thy1.1) mice with subsequent MTB infection of the Thy1.2 mice resulted in a greater burden of MTB in the lungs and spleens than those that received Tregs from air-exposed mice. Mice that received Tregs from donor CS-exposed mice and infected with MTB had modest but significantly reduced numbers of interleukin-12-positive dendritic cells and interferon-gamma-positive CD4+ T cells in the lungs, and an increased number of total programmed cell death protein-1 (PD-1) positive CD4+ T cells in both the lungs and spleens.

Discussion

Previous studies demonstrated that CS impairs macrophages and host-protective T effector cells in controlling MTB infection. We now show that CS-exposed Tregs can also impair control of MTB in co-culture with macrophages and in a murine model.

The impact of comorbidities on tuberculosis treatment outcomes in Poland: a national cohort study

Background

Tuberculosis (TB) is a complex disease associated with other medical conditions, that may affect disease severity. This study aimed to investigate the impact of comorbidities on treatment outcomes and mortality rates in patients with TB in Poland.

Methods

We analyzed a national cohort of 19,217 adult TB patients diagnosed between 2011 and 2016 in Poland. We compared treatment success rates and mortality rates in patients with comorbidities and those without to assess the impact of various comorbidities on these outcomes. Odds ratios (OR) were calculated to quantify the association between comorbidities and TB treatment outcomes.

Results

Patients with comorbidities had lower treatment success rates and higher mortality rates. Diabetes was identified as a significant risk factor for increased TB mortality (OR = 1.9) and mortality from all other causes (OR = 4.5). Similar associations were found for alcoholism (OR = 8.3 and OR = 7.1), immunosuppressive therapy (OR = 5.7 and OR = 5.9), and cancer (OR = 3.4 and OR = 15.4). HIV and tobacco use were associated with an increased risk of mortality from causes other than TB, with odds ratios of 28.6 and 2.2, respectively. The overall treatment success rate in the study population was 88.0%, with 9.2% of patients failing to achieve treatment success and 2.8% dying. Comorbidities such as diabetes, alcoholism, substance addiction, immunosuppressive therapy, cancer, and tobacco use increased the risk of tuberculosis treatment failure.

Conclusion

Patients with comorbidities face a higher risk of unsuccessful treatment outcomes and increased mortality. It is essential to implement integrated management strategies that address both TB and comorbid conditions to improve treatment success rates and reduce mortality.

The Trend, Characteristics and Treatment Outcomes in Patients with Tuberculosis Undergoing Thoracic Surgery in the Kyrgyz Republic between 2017 and 2021

Surgery has played an important role in managing complicated tuberculosis in former Soviet Union countries, including the Kyrgyz Republic. However, published information is limited. This study aimed to document the trend, characteristics and outcomes of tuberculosis patients who underwent thoracic surgery, using routinely collected data. Between 2017 and 2021, 4-7% of tuberculosis patients in the Kyrgyz Republic underwent thoracic surgery in two centres in Bishkek and Osh. In 2021, case records were retrieved in 264 (78%) of 340 patients undergoing thoracic surgery in the country. The most common indications for surgery were pleural exudate/empyema in 127 (44%) and tuberculoma in 83 (32%). Most patients (73%) underwent surgery within 30 days of starting TB treatment. Two-thirds of patients underwent radical surgery, and surgical outcomes were excellent in 99% of patients with one death. Post-operatively, 63 (23%) patients had no TB detected by the histology, with the two most common specified conditions being lung cancer and pulmonary hydatid disease. TB treatment was stopped in these patients. Of the 201 patients with confirmed TB after surgery, TB-treatment success was documented in 163 (81%), died/failure/lost to follow-up in 10 (5%) and not evaluated in 28 (14%). This study shows that thoracic surgery is feasible, safe and effective in the routine programme setting. Recommendations are made to strengthen referral and monitoring systems.

Managing Comorbidities, Determinants and Disability at Start and End of TB Treatment under Routine Program Conditions in China

Many patients with tuberculosis (TB) have comorbidities, risk determinants and disability that co-exist at diagnosis, during and after TB treatment. We conducted an observational cohort study in 11 health facilities in China to assess under routine program conditions (i) the burden of these problems at the start and end of TB treatment and (ii) whether referral mechanisms for further care were functional. There were 603 patients registered with drug-susceptible TB who started TB treatment: 84% were symptomatic, 14% had diabetes, 14% had high blood pressure, 19% smoked cigarettes, 10% drank excess alcohol and in 45% the 6 min walking test (6MWT) was abnormal. Five patients were identified with mental health disorders. There were 586 (97%) patients who successfully completed TB treatment six months later. Of these, 18% were still symptomatic, 12% had diabetes (the remainder with diabetes failed to complete treatment), 5% had high blood pressure, 5% smoked cigarettes, 1% drank excess alcohol and 25% had an abnormal 6MWT. Referral mechanisms for the care of comorbidities and determinants worked well except for mental health and pulmonary rehabilitation for disability. There is need for more programmatic-related studies in other countries to build the evidence base for care of TB-related conditions and disability.

T-BACCO SCORE: A predictive scoring tool for tuberculosis (TB) loss to follow-up among TB smokers

INTRODUCTION

Loss to follow-up (LTFU) and smoking during TB treatment are major challenges for TB control programs. Smoking increases the severity and prolongs TB treatment duration, which lead to a higher rate of LTFU. We aim to develop a prognostic scoring tool to predict LTFU among TB patients who smoke to improve successful TB treatment outcomes.

MATERIALS AND METHODS

The development of the prognostic model utilized prospectively collected longitudinal data of adult TB patients who smoked in the state of Selangor between 2013 until 2017, which were obtained from the Malaysian Tuberculosis Information System (MyTB) database. Data were randomly split into development and internal validation cohorts. A simple prognostic score (T-BACCO SCORE) was constructed based on the regression coefficients of predictors in the final logistic model of the development cohort. Estimated missing data was 2.8% from the development cohort and was completely at random. Model discrimination was determined using c-statistics (AUCs), and calibration was based on the Hosmer and Lemeshow goodness of fit test and calibration plot.

RESULTS

The model highlights several variables with different T-BACCO SCORE values as predictors for LTFU among TB patients who smoke (e.g., age group, ethnicity, locality, nationality, educational level, monthly income level, employment status, TB case category, TB detection methods, X-ray categories, HIV status, and sputum status). The prognostic scores were categorized into three groups that predict the risk for LTFU: low-risk (<15 points), medium-risk (15 to 25 points) and high-risk (> 25 points). The model exhibited fair discrimination with a c-statistic of 0.681 (95% CI 0.627-0.710) and good calibration with a nonsignificant chi-square Hosmer‒Lemeshow's goodness of fit test χ2 = 4.893 and accompanying p value of 0.769.

CONCLUSION

Predicting LTFU among TB patients who smoke in the early phase of TB treatment is achievable using this simple T-BACCO SCORE. The applicability of the tool in clinical settings helps health care professionals manage TB smokers based on their risk scores. Further external validation should be carried out prior to use.

Treatment Outcomes and Associated Factors among Tuberculosis Patients from Selected Rural Eastern Cape Hospitals: An Ambidirectional Study

An essential metric for determining the efficacy of tuberculosis (TB) control programs is the evaluation of TB treatment outcomes; this study was conducted to investigate treatment outcomes and associated factors among tuberculosis patients in rural areas of Eastern Cape, South Africa. Assessing treatment outcomes is fundamental to facilitating the End TB Strategy's set target. Clinic records from 457 patients with DR-TB were examined for data collection while 101 patients were followed up prospectively. Data were analyzed using Stata version 17.0. The odds ratio and 95% confidence interval were calculated to check the association between variables. p ≤ 0.05 was considered statistically significant. Of the 427 participants, 65.8% had successful treatment whilst 34.2% had unsuccessful TB treatment. A total of 61.2% and 39% of the HIV-positive and HIV-negative participants had a successful TB treatment whilst 66% and 34% of both HIV-negative and positive participants had unsuccessful TB treatment. From the 101 patients that were followed up, smokers took longer to have treatment outcomes compared to non-smokers. In the study with HIV/TB co-infection, men predominated. HIV and tuberculosis co-infection made therapy difficult with unfavorable effects on TB management. The treatment success rate (65.8%) was lower than the WHO threshold standard with a high proportion of patients being lost to the follow up. The co-infection of tuberculosis and HIV resulted in undesirable treatment outcomes. Strengthening TB surveillance and control is recommended.

Predictors of mortality and survival probability distribution among patients on tuberculosis treatment in Vihiga County, Kenya

Background

Tuberculosis (TB) related mortality remains a serious impediment in ending TB epidemic.

Objective

To estimate survival probability and identify predictors, causes and conditions contributing to mortality among TB patients in Vihiga County.

Methods

A cohort of 291 patients from 20 purposively selected health facilities were prospectively considered. Data was obtained by validated questionnaires through face-to-face interviews. Survival probabilities were estimated using Kaplan-Meier method while Cox proportional hazard model identified predictors of TB mortality through calculation of hazard ratios at 95% confidence intervals. Mortality audit data was qualitatively categorized to elicit causes and conditions contributing to mortality.

Results

209 (72%) were male, median age was 40 (IQR=32-53) years while TB/HIV coinfection rate was 35%. Overall, 45 (15%) patients died, majority (78% (log rank<0.001)) during intensive phase. The overall mortality rate was 32.2 (95% CI 23.5 - 43.1) deaths per 1000 person months and six months' survival probability was 0.838 (95% CI, 0.796-0.883). Mortality was higher (27%) among HIV positive than HIV negative (9%) TB patients. Independent predictors of mortality included; comorbidities (HR = 2.72, 95% CI,1.36-5.44, p< 0.005), severe illness (HR=5.06, 95% CI,1.59-16.1, p=0.006), HIV infection (HR=2.56, 95% CI,1.28-5.12, p=0.008) and smoking (HR=2.79, 95% CI,1.01-7.75, p=0.049). Independent predictors of mortality among HIV negative patients included; comorbidities (HR = 4.25, 95% CI; 1.15-15.7, p = 0.03) and being clinically diagnosed (HR = 4.8, 95% CI; 1.43-16, P = 0.01) while among HIV positive; they included smoking (HR = 4.05, 95% CI;1.03-16.0, P = 0.04), severe illness (HR = 5.84, 95% CI; 1.08-31.6, P = 0.04), severe malnutrition (HR = 4.56, 95% CI; 1.33-15.6, P = 0.01) and comorbidities (HR = 3.04, 95% CI; 1.03-8.97, p = 0.04). More than a half (52%) of mortality among HIV positive were ascribed to advanced HIV diseases while majority of (72%) of HIV negative patients died to TB related lung disease. Conditions contributing to mortality were largely patient and health system related.

Conclusion

Risk of TB mortality is high and is attributable to comorbidities, severe illness, HIV and smoking. Causes and conditions contributing to TB mortality are multifaceted but modifiable. Improving TB/HIV care could reduce mortality in this setting.

Effects of smoking on the severity and transmission of pulmonary tuberculosis: A hospital-based case control study

Introduction

There is a high incidence of both smoking and tuberculosis (TB) in China. This study examined the risk factors for severe pulmonary TB (PTB) and positive tubercle bacilli in sputum.

Methods

We conducted a retrospective case-control study in a tertiary hospital from January 2017 to December 2018 (n = 917). The clinical and biological characteristics of patients were collected, and univariable and multivariable logistic regression analyses were performed to assess the factors associated with smoking in terms of the severity and transmission of PTB.

Results

Positive tubercle bacilli in sputum and severe PTB were much higher in smoking patients. Together with nutrition status, heavy smoking exhibited a 284% greater risk in severe PTB. Positive tubercle bacilli in sputum was significantly associated with hypoproteinemia and smoking regardless of the status, duration, and degree.

Conclusion

Because cigarette smoking was strongly and inversely associated with hypoproteinemia, we conclude that smoking plays a critical role in the severity and transmission of PTB. Smoking cessation interventions should be employed to prevent severe PTB and decrease the transmission of PTB.

The prevalence of pulmonary hypertension after successful tuberculosis treatment in a community sample of adult patients

There are an estimated 155 million survivors of tuberculosis (TB). Clinical experience suggests that post tuberculosis lung disease (PTLD) is an important cause of Group 3 pulmonary hypertension (PH). However, TB is not listed as a cause of PH in most guidelines. A cross-sectional, community-based study was conducted in nonhealthcare seeking adults who had successfully completed TB treatment. Subjects underwent questionnaires, spirometry, a 6-min walk distance test (6MWD) and transthoracic echocardiography (TTE). Screen probable PH was defined on TTE as an estimated pulmonary artery peak systolic pressure (PASP) of ≥40 mmHg. One hundred adults (71 males) were enrolled, with a mean age of 42 years (SD 13.8 years) and a median of one TB episode (interquartile range: 1-2). Co-morbidities included hypertension (21%), diabetes (16%), human immunodeficiency virus (10%) and asthma/COPD (5%). Only 25% had no residual symptoms after TB. Probable PH was found in 9%, while 7% had borderline raised PASP values (PASP 35-40 mmHg). An association was found between PH and the number of previous TB episodes, with each additional episode of TB increasing the odds of PH-postTB 2.13-fold (confidence interval [CI]: 1.17-3.88; p = 0.013). All of those found to have PH were smokers or ex-smokers yielding an unadjusted odds ratio for PH-postTB of 3.67 (95% CI: 0.77-17.46). There was no statistical difference in spirometry or 6MWD, between those with and without PH. Neither symptoms nor co-morbidities demonstrated significant association with PH. PH after TB was a common finding in this community-based population. Further research is needed to confirm and determine the significance of these findings.

Tuberkulose im Erwachsenenalter

Die Tuberkulose ist in Deutschland eine seltene, überwiegend gut behandelbare Erkrankung. Weltweit ist sie eine der häufigsten Infektionserkrankungen mit ca. 10 Millionen Neuerkrankungen/Jahr. Auch bei einer niedrigen Inzidenz in Deutschland bleibt Tuberkulose insbesondere aufgrund der internationalen Entwicklungen und Migrationsbewegungen eine wichtige Differenzialdiagnose. In Deutschland besteht, aufgrund der niedrigen Prävalenz der Erkrankung und der damit verbundenen abnehmenden klinischen Erfahrung, ein Informationsbedarf zu allen Aspekten der Tuberkulose und ihrer Kontrolle. Diese Leitlinie umfasst die mikrobiologische Diagnostik, die Grundprinzipien der Standardtherapie, die Behandlung verschiedener Organmanifestationen, den Umgang mit typischen unerwünschten Arzneimittelwirkungen, die Besonderheiten in der Diagnostik und Therapie resistenter Tuberkulose sowie die Behandlung bei TB-HIV-Koinfektion. Sie geht darüber hinaus auf Versorgungsaspekte und gesetzliche Regelungen wie auch auf die Diagnosestellung und präventive Therapie einer latenten tuberkulösen Infektion ein. Es wird ausgeführt, wann es der Behandlung durch spezialisierte Zentren bedarf.

Die Aktualisierung der S2k-Leitlinie „Tuberkulose im Erwachsenenalter“ soll allen in der Tuberkuloseversorgung Tätigen als Richtschnur für die Prävention, die Diagnose und die Therapie der Tuberkulose dienen und helfen, den heutigen Herausforderungen im Umgang mit Tuberkulose in Deutschland gewachsen zu sein.

Cigarette smoking is associated with an increase in blood monocytes in people with tuberculosis: A cross-sectional study

The effect of smoking on immune responses in people with tuberculosis (TB) is not well elucidated. We aimed to compare peripheral blood counts of CD4+ and CD87 + T-lymphocytes, monocytes, and neutrophils and the CD4:CD8 ratio in TB patients with and without history of cigarette smoking. We further determined factors associated with current smoking. Participants with TB were consecutively enrolled in a cross-sectional study at a national TB treatment center in Uganda in 2018. We compared cell counts and the CD4:CD8 ratio using the median test among never smokers, past smokers (>6 months ago) and current smokers (≤6 months). Factors associated with current smoking were determined using logistic regression. A post hoc analysis for factors associated with an increase in the monocytes was also performed. Of 363 participants, there were 258 (71.1%) never smokers, 50 (13.8%) past smokers, and 55 (15.2%) current smokers. Most current smokers (49.1%) had a high sputum mycobacterial load. They also had the lowest body mass index and the highest axillary temperature. The median (interquartile range [IQR]) monocyte count among current smokers was 815 (540-1425) cells/mm3 and was significantly higher than that among past smokers (610 (350-900) cells/mm3, P = .017) and never smokers (560 [400-800] cells/mm3, P = .001). The monocyte counts positively correlated with the number of cigarettes smoked per day among current smokers (R = 0.43, P = .006). Current smokers also had higher neutrophil and CD4+ T-cell counts than never smokers. In a multivariable logistic regression model, an increase in the monocyte count was associated with current cigarette smoking (adjusted odds ratio [aOR] = 4.82, 95% confidence interval 1.61-14.39, P = .005). Similarly, current cigarette smoking was independently associated with an increase in the monocyte count (aOR = 1.80, 95% CI 1.39-2.32, P < .001). Cigarette smoking is associated with an increase in the blood monocytes in people with TB in a dose- and time-dependent manner. Further, current smoking is associated with an increase in neutrophils and CD4+ T-lymphocytes. The findings suggest that current smokers have systemic inflammation that is not necessarily beneficial to TB control in TB patients.

Global, regional, and national burden of cancers attributable to tobacco smoking in 204 countries and territories, 1990-2019

BACKGROUND

Cancers are leading causes of mortality and morbidity, with smoking being recognized as a significant risk factor for many types of cancer. We aimed to report the cancer burden attributable to tobacco smoking by sex, age, socio-demographic index (SDI), and cancer type in 204 countries and territories from 1990 to 2019.

METHODS

The burden of cancers attributable to smoking was reported between 1990 and 2019, based upon the Comparative Risk Assessment approach used in the Global Burden of Disease (GBD) study 2019.

RESULTS

Globally, in 2019 there were an estimated 2.5 million cancer-related deaths (95% UI: 2.3 to 2.7) and 56.4 million DALYs (51.3 to 61.7) attributable to smoking. The global age-standardized death and DALY rates of cancers attributable to smoking per 100,000 decreased by 23.0% (-29.5 to -15.8) and 28.6% (-35.1 to -21.5), respectively, over the period 1990-2019. Central Europe (50.4 [44.4 to 57.6]) and Western Sub-Saharan Africa (6.7 [5.7 to 8.0]) had the highest and lowest age-standardized death rates, respectively, for cancers attributable to smoking. In 2019, the age-standardized DALY rate of cancers attributable to smoking was highest in Greenland (2224.0 [1804.5 to 2678.8]) and lowest in Ethiopia (72.2 [51.2 to 98.0]). Also in 2019, the global number of DALYs was highest in the 65-69 age group and there was a positive association between SDI and the age-standardized DALY rate.

CONCLUSIONS

The results of this study clearly illustrate that renewed efforts are required to increase utilization of evidence-based smoking cessation support in order to reduce the burden of smoking-related diseases.

The impact of behavioural risk factors on communicable diseases: a systematic review of reviews

Background

The coronavirus (COVID-19) pandemic has highlighted that individuals with behavioural risk factors commonly associated with non-communicable diseases (NCDs), such as smoking, harmful alcohol use, obesity, and physical inactivity, are more likely to experience severe symptoms from COVID-19. These risk factors have been shown to increase the risk of NCDs, but less is known about their broader influence on communicable diseases. Taking a wide focus on a range of common communicable diseases, this review aimed to synthesise research examining the impact of behavioural risk factors commonly associated with NCDs on risks of contracting, or having more severe outcomes from, communicable diseases.

Methods

Literature searches identified systematic reviews and meta-analyses that examined the association between behavioural risk factors (alcohol, smoking, illicit drug use, physical inactivity, obesity and poor diet) and the contraction/severity of common communicable diseases, including infection or associated pathogens. An a priori, prospectively registered protocol was followed (PROSPERO; registration number CRD42020223890).

Results

Fifty-three systematic reviews were included, of which 36 were also meta-analyses. Reviews focused on: tuberculosis, human immunodeficiency virus, hepatitis C virus, hepatitis B virus, invasive bacterial diseases, pneumonia, influenza, and COVID-19. Twenty-one reviews examined the association between behavioural risk factors and communicable disease contraction and 35 examined their association with communicable disease outcomes (three examined their association with both contraction and outcomes). Fifty out of 53 reviews (94%) concluded that at least one of the behavioural risk factors studied increased the risk of contracting or experiencing worse health outcomes from a communicable disease. Across all reviews, effect sizes, where calculated, ranged from 0.83 to 8.22.

Conclusions

Behavioural risk factors play a significant role in the risk of contracting and experiencing more severe outcomes from communicable diseases. Prevention of communicable diseases is likely to be most successful if it involves the prevention of behavioural risk factors commonly associated with NCDs. These findings are important for understanding risks associated with communicable disease, and timely, given the COVID-19 pandemic and the need for improvements in future pandemic preparedness. Addressing behavioural risk factors should be an important part of work to build resilience against any emerging and future epidemics and pandemics.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-12148-y.

Tuberculosis in Adolescents and Young Adults: Emerging Data on TB Transmission and Prevention among Vulnerable Young People

Adolescents and young adults (AYA, ages 10-24 years) comprise a uniquely important but understudied population in global efforts to end tuberculosis (TB), the leading infectious cause of death by a single agent worldwide prior to the COVID-19 pandemic. While TB prevention and care strategies often overlook AYA by grouping them with either children or adults, AYA have particular physiologic, developmental, and social characteristics that require dedicated approaches. This review describes current evidence on the prevention and control of TB among AYA, including approaches to TB screening, dynamics of TB transmission among AYA, and management challenges within the context of unique developmental needs. Challenges are considered for vulnerable groups of AYA such as migrants and refugees; AYA experiencing homelessness, incarceration, or substance use; and AYA living with HIV. We outline areas for needed research and implementation strategies to address TB among AYA globally.

Measuring fidelity to delivery of a new smoking cessation intervention integrated into routine tuberculosis care in Pakistan and Bangladesh: Contextual differences and opportunities

INTRODUCTION

Tobacco smoking among tuberculosis (TB) patients leads to poorer treatment outcomes. Smoking cessation support should be integrated into routine TB care. We measured healthcare providers' fidelity to a smoking cessation intervention integrated into routine TB care, in Bangladesh and Pakistan. We aimed to understand the role of providers and settings in the implementation of behavior support (BS) messages for TB and smoking cessation.

METHODS

The integrated BS intervention was implemented in TB clinics (24 public and 1 private). Cross-sectional data were collected on the fidelity of delivery of the BS intervention using a predefined fidelity index based on an existing validated method of measuring intervention fidelity. Audio-recordings of patient-provider BS sessions were coded using the fidelity index. Intervention fidelity was presented as the proportion of sessions that implemented BS messages.

RESULTS

A total of 96 sessions were conducted, 37 in Bangladesh and 59 in Pakistan. In public settings, TB medication advice was offered in 91.9% (95% CI: 78.7- 97.2) of sessions in Bangladesh, and in 75.5% (95% CI: 62.4-85.1) of sessions in Pakistan; whilst it was offered in 83.3% (95% CI: 43.7-97.0) of sessions in the private setting in Pakistan. Patients' smoking status was assessed in 70.3% (95% CI: 54.2-82.5) of sessions in Bangladesh, and in 34.0% (95% CI: 22.7-47.4) of sessions in the public setting and in 66.7% (95% CI: 30.0-90.3) of sessions in the private setting in Pakistan. A quit date was set in 32.4% (95% CI: 19.6-48.5) of all sessions in Bangladesh, and in 33.3% (95% CI: 9.6-70.0) of all sessions in the public setting in Pakistan.

CONCLUSIONS

Fidelity to the intended delivery of the intervention was found to be high for TB-related messages but not for smoking cessation messages. Clinic contexts may play a mediating role in health workers' opportunities to deliver the intervention as planned.

TRIAL REGISTRATION

International Standard Randomized Clinical Trial Number (ISRCTN43811467). Registered 23 March 2016, https://doi.org/10.1186/ISRCTN43811467.

Revisiting the tax treatment of bidis in India

Background

Bidi use remains an intractable public health problem for India. This is partly due to the informal nature of the bidi supply chain, including tax exemptions for small producers. The aim of this paper is to assess the impact of making all bidis subject to duty and Goods and Services Tax. Although this may require legislative changes and incur some extra administrative costs, the net benefits would include greater oversight of the supply chain as well as increased tax revenues and reduced consumption.

Methods

We use a form of gap analysis (the difference between duty paid and total bidi consumption) to estimate the number of tax-exempt bidis. We then use local evidence on the price elasticity of demand for bidis to assess the impact of eliminating these exemptions on the price and consumption of presently tax-exempt bidis.

Findings

Total bidi consumption is estimated at 400 billion sticks per annum, including 275 billion duty paid sticks and 125 billion duty exempt sticks. Removing the small producer exemptions would increase the price of currently exempt bidis by INR4.6/pack. Total bidi consumption would decrease by 6% and the number of smokers would decrease by 2.2 million adults. This would bring the rate of bidi smoking down from 7.7% to 7.5%, while generating INR14.8 billion in tax revenues.

Conclusions

Eliminating India’s tax exemptions for small bidis producers would make a significant contribution to tobacco control, both directly by reducing the number of smokers and indirectly by plugging a loophole in the supply chain.

Tobacco use and nicotine dependence among newly diagnosed pulmonary tuberculosis patients in Ballabgarh tuberculosis unit, Haryana

Introduction:

This study was conducted to estimate the burden of tobacco use and nicotine dependence among newly diagnosed pulmonary tuberculosis patients to help inform effective implementation of tobacco cessation strategies among tuberculosis patients to improve treatment outcomes.

Materials and Methods:

This was a cross-sectional study conducted among 211 consecutive newly diagnosed pulmonary tuberculosis patients between July 2018 till January 2019 at Ballabgarh tuberculosis unit (TU) in Faridabad district of Haryana, India. All participants were administered a pre-tested questionnaire to assess tobacco use and the Fagerstrom test for nicotine dependence (FTND) to assess nicotine dependence. Current tobacco users were defined as those who smoked in the past 7 days. Nicotine dependence was classified as low, moderate, or high for the FTND score of 0-3, 4-6, and 7-10, respectively.

Results:

Majority of the participants (71.1%) were male, aged 26–50 years (45.5%), and married (65.4%). Fifty (23.7%, CI: 18.0–29.4) participants were currently using tobacco; 29 (13.7%, CI: 9.1–18.4) reported smoking tobacco while 23 (10.9%, CI: 6.7–15.1) reported using smokeless tobacco. In the last month, the proportion of patients who attempted to quit smoking and smokeless tobacco was 31% and 26.1%, respectively. 86.2% of the smokers and 69.6% smokeless tobacco users reported moderate to a high level of nicotine dependence.

Conclusion:

High prevalence of tobacco use, a higher level of nicotine dependence and inability to quit despite an attempt among a large number of tuberculosis patients, necessitates the inclusion of routine tobacco cessation advice and nicotine replacement therapy in tuberculosis care.