Risk factors associated with tuberculosis recurrence in South Korea determined using a nationwide cohort study

Examining the efficacy of treatment outcomes for patients with pulmonary tuberculosis in Western China: A retrospective study in a region of high incidence

BACKGROUND

Guizhou, situated in western China, exhibits a high incidence of pulmonary tuberculosis (PTB) alongside comparatively challenging medical and economic conditions. Our objective was to investigate the determinants influencing successful PTB treatment and their scope, aiming to provide a scientific foundation for targeted interventions and enhancing treatment efficacy.

METHODS

Data encompassing all PTB cases registered in Guizhou's China Disease Prevention and Control Information System from 2017 to 2022 were analyzed. Using the successful treatment rate as the dependent variable, initial univariate analysis of independent variables was conducted, followed by multilevel binary logistic regression analysis to assess variables demonstrating statistically significant disparities.

RESULTS

A total of 139,414 patients (average age: 44 years) were included, with 64.41% male and 35.59% female. Among them, 47.57% were etiologically positive and 16.35% had comorbidities. The overall successful treatment rate was 95.77%, with a cure rate of 42.54%. Nine factors were identified to influence treatment success, including a higher proportion of females (OR = 1.178), students versus farmers (OR = 1.960), and etiologically negative cases (OR = 1.831). Initial treatment showed better success rates than retreatment (OR = 3.046), and patients without comorbidities had higher success rates than those with comorbidities (OR = 1.303). Fixed-dose combination therapy (FDC) also yielded better outcomes (OR = 1.296). Ethnic differences were noted, with the Miao group having lower success rates (OR = 0.874) and the Buyi group higher success rates (OR = 1.270) compared to Han. Age was another factor, with success rates decreasing in the 41-60 (OR = 0.731) and 61 + age groups (OR = 0.604).

CONCLUSIONS

Western China faces ongoing challenges in enhancing its PTB treatment capacity and should prioritize the promotion of FDC therapy. Risk factors that influence treatment outcomes for PTB include male gender, advanced age, belonging to the Miao ethnic group, occupation as a farmer, etiological positivity, retreatment status, and comorbidities such as diabetes and HIV/AIDS. Further investigation is warranted to explore the disparities in successful treatment rates among different ethnicities.

Tuberculosis treatment outcomes and associated factors: A retrospective study in West Nusa Tenggara, Indonesia

Successfully treating tuberculosis (TB) could significantly help reduce its spread. The aim of this study was to identify factors associated with successful TB treatment. A retrospective study was conducted in West Nusa Tenggara, Indonesia, using data from the National TB Information System (SITB) covering patients from January 1 to December 31, 2022. Patients were classified into two groups: those with successful treatment outcomes (cured or completed treatment) and those with unsuccessful outcomes (including treatment failure, loss to follow-up, or death). Univariate and multivariate logistic regression analyses were performed to identify factors associated with treatment outcomes, providing odds ratios (OR) and adjusted odds ratios (aOR) with 95% confidence intervals (CIs). A total of 2,225 TB patients (1,382 males and 843 females) were included in the study. Of these, 2,048 (92.1%) achieved successful treatment outcomes. Univariate analysis indicated that older age (OR: 0.47; 95%CI: 0.28-0.78) and a high number of AFB in sputum smears (OR: 0.23; 95%CI: 0.09-0.66) were associated with a higher likelihood of unsuccessful TB treatment. In contrast, having no HIV infection (OR: 13.44; 95%CI: 6.22-29.08), clinical TB cases (diagnosed clinically rather than bacteriologically) (OR: 1.50; 95%CI: 1.04-2.20) and longer duration of TB treatments were associated with successful treatment outcomes. Multivariate analysis suggested that the TB treatment durations of 4-6 months (aOR: 1256.95; 95%CI: 431.89-3658.19) and 7-12 months (aOR: 575.5; 95%CI: 99.1-3342.06) were associated with a significantly higher likelihood of success compared to durations of 0-3 months. In conclusion, this study highlights that a minimum treatment duration of three months was crucial for increasing the likelihood of successful TB treatment. These findings emphasize the importance of comprehensive support programs to ensure adherence to treatment guidelines and improve outcomes.

Impact of Mass Screening Using Chest X-Ray on Mortality Reduction and Treatment Adherence Among Pulmonary Tuberculosis Patients

BACKGROUND

Evaluate the impact of chest X-ray (CXR) screening on mortality and treatment adherence by comparing pulmonary tuberculosis (PTB) cases detected through screening and those routinely diagnosed at healthcare facilities.

METHODS

A retrospective analysis of 10% randomly sampled National Health Insurance Service claims data assessed PTB cases diagnosed during 2004-2020. Patients were categorized as 'screening-detected (ACF, active case finding)' or 'routinely detected (PCF, passive case finding)' based on CXR screening history. Cox proportional hazards model determined the association between screening and all-cause or tuberculosis (TB)-specific mortality. Treatment adherence was also measured.

RESULTS

Among 84,828 PTB patients, 18.76% were ACF (15,916), and 81.24% were PCF (68,912). ACF exhibited lower risks in all-cause mortality (adjusted hazard ratio [aHR], 0.70; 95% confidence interval [CI], 0.67-0.73) and TB-specific mortality (aHR, 0.38; 95% CI, 0.32-0.46) compared to PCF. In the ACF group, 91.39% initiated anti-TB treatment, with 45.99% adherence. For PCF, 92.87% initiated treatment, and only 45.44% were adherent.

CONCLUSION

Individuals undergoing CXR screening have a lower risk of both all-cause and TB-specific mortality compared to PCF, but treatment adherence is similar between the two groups, emphasizing the need to improve the linkage between screening, diagnosis, and treatment for the screened population.

Identifying risk factors for recurrent multidrug resistant tuberculosis based on patient's record data from 2016 to 2021: retrospective study

Globally, the prevalence of multidrug-resistant tuberculosis (MDR-TB) has been increasing recently. This is a major public health concern, as MDR-TB is more difficult to treat and has poorer outcomes compared to drug-sensitive tuberculosis. The main objective of the study was to identify risk factors for recurrent multidrug-resistant tuberculosis, at Alert Specialized Hospital, Addis Ababa, by using different parametric shared frailty models. From January 2016 to December 2021, a retrospective study was conducted on MDR-TB patients at Alert Specialized Hospital in Addis Ababa. The data for the study were collected from the medical records of MDR-TB patients at the hospital during this time period. Gamma and inverse-Gaussian shared frailty models were used to analyze the dataset, with the exponential, Weibull, and lognormal distributions included as baseline hazard functions. The data were analyzed using R statistical software. The median recurrence time of the patients was 12 months, and 149 (34.3%) had recurrences. The clustering effect was statistically significant for multiple drug-resistant tuberculosis patients' recurrence. According to the Weibull-Inverse-Gaussian model, factors that reduced time to MDR-TB recurrence included lower weight (ɸ = 0.944), smoking (ɸ = 0.045), alcohol use (ɸ = 0.631), hemoptysis (ɸ = 0.041), pneumonia (ɸ = 0.564), previous anti-TB treatment (ɸ = 0.106), rural residence (ɸ = 0.163), and chronic diseases like diabetes (ɸ = 0.442) were associated with faster recurrence. While, higher education (ɸ = 3.525) and age (ɸ = 1.021) extended time to recurrence. For weight increment, smokers and alcohol users, clinical complications of hemoptysis and pneumonia, patients with pulmonary disease who had a history of previous anti-TB treatment, and being rural residents are prognostic factors. There was a significant clustering effect at the Alert Specialized Hospital in Addis Ababa, Ethiopia. The Weibull-Inverse Gaussian Shared Frailty Model was chosen as the best model for predicting the time to recurrence of MDR-TB.

A pharmacometric multistate model for predicting long-term treatment outcomes of patients with pulmonary TB

BACKGROUND

Studying long-term treatment outcomes of TB is time-consuming and impractical. Early and reliable biomarkers reflecting treatment response and capable of predicting long-term outcomes are urgently needed.

OBJECTIVES

To develop a pharmacometric multistate model to evaluate the link between potential predictors and long-term outcomes.

METHODS

Data were obtained from two Phase II clinical trials (TMC207-C208 and TMC207-C209) with bedaquiline on top of a multidrug background regimen. Patients were typically followed throughout a 24 week investigational treatment period plus a 96 week follow-up period. A five-state multistate model (active TB, converted, recurrent TB, dropout, and death) was developed to describe observed transitions. Evaluated predictors included patient characteristics, baseline TB disease severity and on-treatment biomarkers.

RESULTS

A fast bacterial clearance in the first 2 weeks and low TB bacterial burden at baseline increased probability to achieve conversion, whereas patients with XDR-TB were less likely to reach conversion. Higher estimated mycobacterial load at the end of 24 week treatment increased the probability of recurrence. At 120 weeks, the model predicted 55% (95% prediction interval, 50%-60%), 6.5% (4.2%-9.0%) and 7.5% (5.2%-10%) of patients in converted, recurrent TB and death states, respectively. Simulations predicted a substantial increase of recurrence after 24 weeks in patients with slow bacterial clearance regardless of baseline bacterial burden.

CONCLUSIONS

The developed multistate model successfully described TB treatment outcomes. The multistate modelling framework enables prediction of several outcomes simultaneously, and allows mechanistically sound investigation of novel promising predictors. This may help support future biomarker evaluation, clinical trial design and analysis.

Diabetes as a risk factor for tuberculosis disease

BACKGROUND

Tuberculosis (TB) is amongst the leading causes of death from an infectious disease, with an estimated 1.3 million deaths from TB in 2022. Approximately 25% of the global population is estimated to be infected with the TB bacterium, giving rise to 10.6 million episodes of TB disease in 2022. The prevalence of diabetes influences TB incidence and TB mortality. It is associated not only with an increased risk of TB disease but also death during TB treatment, TB relapse after treatment completion and multidrug-resistant TB. Since 2011, the World Health Organization (WHO) has recommended collaborative TB and diabetes activities as outlined in the Collaborative Framework for Care and Control of TB and Diabetes.

OBJECTIVES

To determine the prognostic value of diabetes mellitus (DM) in the general population of adults, adolescents and children for predicting tuberculosis disease.

SEARCH METHODS

We searched the literature databases MEDLINE (via PubMed) and WHO Global Index Medicus, and the WHO International Clinical Trials Registry Platform (ICTRP) on 3 May 2023 (date of last search for all databases); we placed no restrictions on the language of publication.

SELECTION CRITERIA

We included retrospective and prospective cohort studies, irrespective of publication status or language. The target population comprised adults, adolescents and children from diverse settings, encompassing outpatient and inpatient cohorts, with varying comorbidities and risk of exposure to tuberculosis.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodology and the Quality In Prognosis Studies (QUIPS) tool. Prognostic factors assessed at enrolment/baseline included diabetes, as defined by the individual studies, encompassing patient-reported status, abstracted from medical records or claims data, or diagnosed by plasma glucose/glycosylated haemoglobin. The primary outcome was the incidence of tuberculosis disease. The secondary outcome was recurrent TB disease. We performed a random-effects meta-analysis for the adjusted hazard ratios, risk ratios, or odds ratios, employing the restricted maximum likelihood estimation. We rated the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We included 48 cohort studies with over 61 million participants from the six WHO regions. However, the representation was variable as eight population-based studies were from South Korea and 19 from China, with overlapping study periods, and only one from the African region (Ethiopia). All studies included adults, and nine studies also included children and adolescents. Most studies diagnosed DM based on clinical records, including fasting blood glucose levels or glucose-lowering treatments. The studies did not distinguish between type 1 and type 2 DM; only one study focused on type 1 DM. Diagnosis and exclusion of TB were performed using culture or molecular WHO-recommended rapid diagnostic tests (mWRD) in only 12 studies, which could have biassed the effect estimate. The median follow-up time was five years (interquartile range 1.5 to 10, range 1 to 16.9), and the studies primarily reported an adjusted hazard ratio from a multivariable Cox-proportional hazard model. Hazard Ratios (HR) The HR estimates represent the highest certainty of the evidence, explored through sensitivity analyses and excluding studies at high risk of bias. We present 95% confidence intervals (CI) and prediction intervals, which show between-study heterogeneity represented in measuring the variability of effect sizes (i.e. the interval within which the effect size of a new study would fall considering the same population of studies included in the meta-analysis). DM may increase the risk of tuberculosis disease (HR 1.90, 95% CI 1.51 to 2.40; prediction interval 0.83 to 4.39; 10 studies; 11,713,023 participants). The certainty of the evidence is low, due to a moderate risk of bias across studies and inconsistency. Considering a risk without diabetes of 129 cases per 100,000 population, this represents 102 more (59 to 153 more) cases per 100,000. When stratified by follow-up time, the results are more consistent across < 10 years follow-up (HR 1.52, 95% CI 1.47 to 1.57; prediction interval 1.45 to 1.59; 7 studies; 10,380,872 participants). This results in a moderate certainty of the evidence due to a moderate risk of bias across studies. However, at 10 or more years of follow-up, the estimates yield a wider CI and a higher HR (HR 2.44, 95% CI 1.22 to 4.88; prediction interval 0.09 to 69.12; 3 studies; 1,332,151 participants). The certainty of the evidence is low due to the moderate risk of bias and inconsistency. Odds Ratio (OR) DM may increase the odds of tuberculosis disease (OR 1.61, 95% CI 1.27 to 2.04; prediction interval 0.96 to 2.70; 4 studies; 167,564 participants). Stratification by follow-up time was not possible as all studies had a follow-up < 10 years. The certainty of the evidence is low due to a moderate risk of bias and inconsistency. Risk Ratio (RR) The RR estimates represent the highest certainty of the evidence, explored through sensitivity analyses and excluding studies at high risk of bias. DM probably increases the risk of tuberculosis disease (RR 1.60, 95% CI 1.42 to 1.80; prediction interval 1.38 to 1.85; 6 studies; 44,058,675 participants). Stratification by follow-up time was not possible as all studies had a follow-up < 10 years. The certainty of the evidence is moderate due to a moderate risk of bias.

AUTHORS' CONCLUSIONS

Diabetes probably increases the risk of developing TB disease in the short term (< 10 years) and may also increase the risk in the long term (≥ 10 years). As glycaemic control and access to care may be potential effect modifiers of the association between diabetes and the risk of TB disease, the overall estimates should be interpreted with caution when applied locally. Policies targeted at reducing the burden of diabetes are needed to contribute to the aims of ending TB. Large population-based cohorts, including those derived from high-quality national registries of exposures (diabetes) and outcomes (TB disease), are needed to provide estimates with a high certainty of evidence of this risk across different settings and populations, including low- and middle-income countries from different WHO regions. Moreover, studies including children and adolescents and currently recommended methods for diagnosing TB would provide more up-to-date information relevant to practice and policy.

FUNDING

World Health Organization (203256442) REGISTRATION: PROSPERO registration: CRD42023408807.

Recurrent Pulmonary Tuberculosis in China, 2005 to 2021

Importance

Despite posing a significant challenge to global tuberculosis (TB) elimination efforts, recurrent TB remains understudied due to the challenges of long-term observation.

Objective

To investigate the burden of recurrent TB using data from patients with pulmonary TB (PTB) in China.

Design, Setting, and Participants

This retrospective cohort study included all bacteriologically confirmed or clinically diagnosed PTB cases reported to the Tuberculosis Information Management System with completed or successful treatment outcomes from January 1, 2005, to December 31, 2021. Data were analyzed from July 15, 2022, to October 28, 2023.

Exposures

Newly diagnosed PTB was classified into primary, hematogenous disseminated, or secondary PTB.

Main Outcomes and Measures

The primary outcome was the annual recurrence rate, stratified by disease classification, over the 17-year observation period. The recurrence rate for year n was calculated by dividing the number of patients with recurrent TB in year n by observed person-years in year n. The secondary outcome was the annual proportion of recurrent TB among reported cases and associated risk factors.

Results

Of 13 833 249 patients with TB reported to the Tuberculosis Information Management System, 10 482 271 with PTB met the inclusion criteria. Of these, 68.9% were male, 22.3% were 65 years or older, 89.6% were of Han ethnicity, and 68.4% were agricultural workers. A total of 413 936 patients experienced a recurrent TB episode after successful treatment, resulting in an overall recurrence rate of 0.47 (95% CI, 0.47-0.48) per 100 person-years. The recurrence rate for patients with primary PTB was 0.24 (95% CI, 0.22-0.26) per 100 person-years; for hematogenous disseminated PTB, 0.37 (95% CI, 0.36-0.38) per 100 person-years; and for secondary PTB, 0.48 (95% CI, 0.47-0.48) per 100 person-years. The cumulative proportion of recurrences within the first 2 years accounted for 48.9% of all recurrent cases. The proportion of recurrent cases among notified incident cases increased 1.9-fold from 4.7% in 2015 to 8.8% in 2021. Among other factors, ages 45 to 64 years (adjusted hazard ratio, 1.77 [95% CI, 1.65-1.89]) and having completed treatment (adjusted hazard ratio, 1.16 [95% CI, 1.14-1.18]) were identified as associated with recurrence.

Conclusions and Relevance

In this retrospective cohort study, the PTB recurrence rate was substantially higher than the incidence, and the proportion of recurrent cases increased. Almost half of the recurrence occurred within the first 2 years, suggesting that routine posttreatment follow-up may represent an important strategy for accelerating TB elimination.

Undernutrition as a risk factor for tuberculosis disease

BACKGROUND

Tuberculosis (TB) is a leading cause of mortality due to an infectious disease, with an estimated 1.6 million deaths due to TB in 2022. Approximately 25% of the global population has TB infection, giving rise to 10.6 million episodes of TB disease in 2022. Undernutrition is a key risk factor for TB and was linked to an estimated 2.2 million TB episodes in 2022, as outlined in the World Health Organization (WHO) Global Tuberculosis Report.

OBJECTIVES

To determine the prognostic value of undernutrition in the general population of adults, adolescents, and children for predicting tuberculosis disease over any time period.

SEARCH METHODS

We searched the literature databases MEDLINE (via PubMed) and WHO Global Index Medicus, as well as the WHO International Clinical Trials Registry Platform (ICTRP) on 3 May 2023 (date of last search for all databases). We placed no restrictions on the language of publication.

SELECTION CRITERIA

We included retrospective and prospective cohort studies, irrespective of publication status or language. The target population comprised adults, adolescents, and children from diverse settings, encompassing outpatient and inpatient cohorts, with varying comorbidities and risk of exposure to tuberculosis.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodology and the Quality In Prognosis Studies (QUIPS) tool to assess the risk of bias of the studies. Prognostic factors included undernutrition, defined as wasting, stunting, and underweight, with specific measures such as body mass index (BMI) less than two standard deviations below the median for children and adolescents and low BMI scores (< 18.5) for adults and adolescents. Prognostication occurred at enrolment/baseline. The primary outcome was the incidence of TB disease. The secondary outcome was recurrent TB disease. We performed a random-effects meta-analysis for the adjusted hazard ratios (HR), risk ratios (RR), or odds ratios (OR), employing the restricted maximum likelihood estimation. We rated the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We included 51 cohort studies with over 27 million participants from the six WHO regions. Sixteen large population-based studies were conducted in China, Singapore, South Korea, and the USA, and 25 studies focused on people living with HIV, which were mainly conducted in the African region. Most studies were in adults, four in children, and three in children and adults. Undernutrition as an exposure was usually defined according to standard criteria; however, the diagnosis of TB did not include a confirmatory culture or molecular diagnosis using a WHO-approved rapid diagnostic test in eight studies. The median follow-up time was 3.5 years, and the studies primarily reported an adjusted hazard ratio from a multivariable Cox-proportional hazard model. Hazard ratios (HR) The HR estimates represent the highest certainty of the evidence, explored through sensitivity analyses and excluding studies at high risk of bias. We present 95% confidence intervals (CI) and prediction intervals, which present between-study heterogeneity represented in a measurement of the variability of effect sizes (i.e. the interval within which the effect size of a new study would fall considering the same population of studies included in the meta-analysis). Undernutrition may increase the risk of TB disease (HR 2.23, 95% CI 1.83 to 2.72; prediction interval 0.98 to 5.05; 23 studies; 2,883,266 participants). The certainty of the evidence is low due to a moderate risk of bias across studies and inconsistency. When stratified by follow-up time, the results are more consistent across < 10 years follow-up (HR 2.02, 95% CI 1.74 to 2.34; prediction interval 1.20 to 3.39; 22 studies; 2,869,077 participants). This results in a moderate certainty of evidence due to a moderate risk of bias across studies. However, at 10 or more years of follow-up, we found only one study with a wider CI and higher HR (HR 12.43, 95% CI 5.74 to 26.91; 14,189 participants). The certainty of the evidence is low due to the moderate risk of bias and indirectness. Odds ratio (OR) Undernutrition may increase the odds of TB disease, but the results are uncertain (OR 1.56, 95% CI 1.13 to 2.17; prediction interval 0.61 to 3.99; 8 studies; 173,497 participants). Stratification by follow-up was not possible as all studies had a follow-up of < 10 years. The certainty of the evidence is very low due to the high risk of bias and inconsistency. Contour-enhanced funnel plots were not reported due to the few studies included. Risk ratio (RR) Undernutrition may increase the risk of TB disease (RR 1.96, 95% CI 1.73 to 2.21; prediction interval 1.50 to 2.56; 4 studies; 1,475,867 participants). Stratification by follow-up was not possible as all studies had a follow-up of < 10 years. The certainty of the evidence is low due to the high risk of bias. Contour-enhanced funnel plots were not reported due to the few studies included.

AUTHORS' CONCLUSIONS

Undernutrition probably increases the risk of TB two-fold in the short term (< 10 years) and may also increase the risk in the long term (> 10 years). Policies targeted towards the reduction of the burden of undernutrition are not only needed to alleviate human suffering due to undernutrition and its many adverse consequences, but are also an important part of the critical measures for ending the TB epidemic by 2030. Large population-based cohorts, including those derived from high-quality national registries of exposures (undernutrition) and outcomes (TB disease), are needed to provide high-certainty estimates of this risk across different settings and populations, including low and middle-income countries from different WHO regions. Moreover, studies including children and adolescents and state-of-the-art methods for diagnosing TB would provide more up-to-date information relevant to practice and policy.

FUNDING

World Health Organization (203256442).

REGISTRATION

PROSPERO registration: CRD42023408807 Protocol: https://doi.org/10.1002/14651858.CD015890.

Time until tuberculosis recurrence and associated factors in Brazil: a populationbased retrospective cohort study using a linked database

OBJECTIVE

To calculate the rate of tuberculosis recurrence, estimate its average time until recurrence, and identify factors associated with recurrence in Brazil.

METHODS

Retrospective cohort study with a linked database from the Notifiable Diseases Information System. The study included individuals diagnosed with tuberculosis in 2015, focusing on those who experienced their first recurrence within 6.5 years. We estimated the relative risk (RR) and its 95% confidence interval (95%CI), as well as the population attributable fraction (PAF) or the population preventable fraction (PPF) of associated factors.

RESULTS

Within a 6.5-year period, 3,253 individuals (6.5%) experienced tuberculosis recurrence, with a median time of 2.2 years. Positively associated factors included: male sex (RR: 1.4; 95%CI 1.3-1.5; PAF: 22.9%), age 30 to 59 years (RR: 3.0; 95%CI 1.6-5.7; PAF: 36.0%), black race (RR: 1.3; 95%CI 1.2-1.5; PAF: 3.5%), mixed race (RR: 1.3; 95%CI 1.2-1.4; PAF: 10.6%), deprivation of liberty (RR: 1.9; 95%CI 1.7-2.1; PAF: 9.1%), pulmonary/mixed clinical form (RR: 1.7; 95%CI 1.4-1.9; PAF: 37.1%), acquired immunodeficiency syndrome diagnosis (RR: 1.8; 95%CI 1.5-1.9; PAF: 4.3%), and alcohol use (RR: 1.2; 95%CI 1.1-1.3; PAF: 2.9%). Negatively associated factors were: 12 or more years of schooling (RR: 0.5; 95%CI 0.4-0.6; PPF: 3.3%) and supervised treatment (RR: 0.9; 95%CI 0.8-0.9; PPF: 4.4%).

CONCLUSION

This study revealed high tuberculosis recurrence rates in Brazil, influenced by sociodemographic, compartmental, and social factors, both positively and negatively impacting disease recurrence.

Components of the Chronic Obstructive Pulmonary Disease Assessment Test Associated with the Exacerbation of Severe Chronic Obstructive Pulmonary Disease Patients

INTRODUCTION

The chronic obstructive pulmonary disease (COPD) Assessment Test (CAT) score is widely used for evaluating the health status of patients diagnosed with COPD. The aim of this study was to identify which components of the CAT are associated with exacerbations in severe COPD patients.

METHODS

Using data from the Korean COPD Subgroup Study (KOCOSS), we identified 3,440 COPD patients, among which 1,027 patients are classified as having severe COPD based on spirometry results. The CAT scores on 8 items were evaluated and classified into respiratory and non-respiratory categories. We analyzed the association between CAT item scores and moderate-to-severe exacerbations during study enrollment and the following years.

RESULTS

Patients with a history of moderate-to-severe exacerbations had higher scores on non-respiratory CAT components. Longitudinal CAT scores on all items after enrollment were higher in the moderate-to-severe exacerbation group. Additionally, the frequency of severe exacerbations was associated with specific CAT components related to limited activities, confidence leaving home, sleeplessness, and energy.

CONCLUSIONS

This study revealed that the non-respiratory CAT component scores were statistically significant factors for predicting the moderate-to-severe exacerbation of severe COPD patients. Non-respiratory symptoms and functional limitations should be considered in patients with severe COPD. Interventions, such as pulmonary rehabilitation, may be needed to improve patients' overall well-being and prevent exacerbations.

Low household income increases the risk of tuberculosis recurrence: a retrospective nationwide cohort study in South Korea

OBJECTIVES

We assessed the impact of household income on tuberculosis (TB) recurrence and the long-term impact of TB on household income.

STUDY DESIGN

This was a retrospective nationwide cohort study of patients with drug-susceptible TB (DS-TB) and TB recurrence.

METHODS

Using the South Korean national TB cohort database, we identified a sub-set cohort of patients with newly diagnosed drug-susceptible TB between 2013 and 2016 and tracked their TB recurrence and longitudinal income data from 2007 to 2018. Income levels were evaluated as 'Medical aid' and quintile categories. To assess risk factors associated with TB recurrence, we used a sub-distribution hazard model, adjusting for the competing risks of death.

RESULTS

Of 66,690 patients successfully treated with DS-TB, 2095 (3.1 %) experienced recurrence during a median follow-up of 39 months. The incidence of TB recurrence was 982.1/100,000 person-years, with 50.3 % of the recurrences occurring within 1 year of treatment completion. The risk of TB recurrence increased with decreasing income levels, with the highest risk observed in the lowest income group. The effect of income on TB recurrence was prominent in males but not in females. Overall, patients with TB recurrence experienced a linear decline in income levels, compared with those without recurrence.

CONCLUSIONS

Household income during the initial TB episode was an important risk factor for TB recurrence, particularly in males.

Assessing the association between the circulating levels of inflammatory cytokines and the risk of tuberculosis: A bidirectional two-sample mendelian randomization study

BACKGROUND

Numerous observational studies have previously reported an association between inflammatory cytokines and tuberculosis (TB). However, the causal relationship between these factors remains unclear. Consequently, we conducted two-sample Mendelian randomization (MR) analyses to ascertain the causal link between levels of inflammatory cytokines and the risk of TB.

METHODS

Single nucleotide polymorphisms (SNPs) robustly associated with the cytokines, located in or close to their coding gene. SNP was obtained from genome-wide association studies (GWAS) of 8293 individuals of Finnish. TB data was obtained from the UK Biobank, which included 46,293 individuals of European ancestry (comprising 2277 TB cases and 46,056 controls). Two-sample, bi-directional MR analyses using inverse-variance weighted (IVW) method as the primary analysis. Followed by comprehensive sensitivity analyses to validate the robustness of results.

RESULT

The study showed that the causal relationship between circulating levels of interleukin (IL)-7 and risk of TB (odds ratio [OR] = 1.001, 95% confidence intervals [CIs]: 1.000, 1.003. p = 0.047). No causal associations were observed between other influencing factors and the occurrence of TB. Furthermore, the analysis revealed that TB infection exhibited negative causal associations with macrophage inflammatory protein 1 alpha ([MIP-1α], OR = 0.007, 95% CI: 0.000, 0.192. p = 0.004), IL-2 (OR = 0.014, 95% CI: 0.010, 0.427. p = 0.014), interleukin-2 receptor alpha chain([IL-2rα], OR = 0.019, 95% CI: 0.001, 0.525. p = 0.019) and basic fibroblast growth factor ([bFGF], OR = 0.066, 95% CI: 0.006, 0.700. p = 0.024).

CONCLUSION

The study has illuminated the causal link between inflammatory cytokines and TB, thereby enhancing our comprehension of the potential mechanisms underlying TB pathogenesis. This discovery offers promising avenues for the identification of novel therapeutic targets in TB treatment. These insights may ultimately pave the way for more effective treatment approaches, thereby improving patient outcomes.

The incidence of tuberculosis recurrence: Impacts of treatment duration of and adherence to standard anti-tuberculous therapy

BACKGROUND

We investigated the impacts of the standard treatment durations of and adherence to standard anti-tuberculous therapy (ATT) on recurrence after the successful completion of tuberculosis (TB) treatment.

METHODS

We recruited patients with TB who had received treatment for six or nine months from the 2008-2017 databases of the Taiwanese National Health Insurance Research Database. Treatment duration and adherence to standard ATT were analyzed for their impacts on recurrence within two years. Complete adherence to standard ATT was defined as daily use of ethambutol, isoniazid, pyrazinamide, and rifampin for the first two months, and daily use of isoniazid and rifampin for the first six months.

RESULTS

A total of 33,298 TB patients with new-onset TB were identified and classified into two groups by treatment duration: six months (n = 25,849, 77.63%) and nine months (n = 7449). Sex and age distributions varied between the groups. Treatment duration did not affect TB recurrence within two years (adjusted hazard ratio (AHR): 1.18, 95% confidence interval (C.I.) [0.96-1.44], p = 0.1156). Multivariable logistic regression showed that incomplete adherence to standard anti-tuberculous therapy (80-89% and 90-99% standard anti-TB therapy, AHR: 1.57, 95% C.I. [1.26-1.95], and 1.63, 95% C.I. [1.26-2.06], respectively, p < 0.0001) increased TB recurrence. In addition, male sex, older age, and comorbidity with diabetes mellitus or chronic obstructive pulmonary disease were independent risk factors for TB recurrence within two years.

CONCLUSIONS

TB recurrence was 1.54% within two years under a DOT era. TB treatment durations of six or nine months did not affect TB recurrence within two years after completion of TB treatment, but incomplete adherence to standard anti-tuberculous therapy might increase the TB recurrence rate.

Recurrence Rate of Pulmonary Tuberculosis in Patients Treated with the Standard 6-Month Regimen: Findings and Implications from a Prospective Observational Multicenter Study

Tuberculosis (TB) recurrence following successful treatment is a significant challenge in TB control programs. However, the rate of TB recurrence varies among studies. It depends on several factors, including the country/region where the investigation occurs, the study design, sample characteristics, and the anti-TB regimen used. In Yemen, a few previous studies examined the rate of TB recurrence and reported high recurrence rates, with a 5-year recurrence rate of approximately 9.5%. However, they were conducted before 2010 using the previous anti-TB regimen which was phased out and replaced with the World Health Organization's (WHO) standard 6-month TB regimen. Consequently, this study aimed to examine the rate of TB recurrence after the implementation of the WHO standard 6-month regimen in Yemen. A prospective observational study was conducted with patients diagnosed with drug-susceptible pulmonary TB. The patients were recruited from five health centers with TB units in five governorates from January to December 2011. All the patients were followed up for five years after treatment completion. A total of 439 patients who completed the anti-TB regimen met the inclusion criteria and were included in the study. During the 5-year follow-up period, 8 patients (1.8%) died, and 13 patients (2.96%) were lost to follow-up, resulting in a final cohort of 418 patients. Of the cohort, 50.5% (n = 211) were male, while 49.5% (n = 207) were female patients. Of the patients, 129 patients (30.9%) were illiterate, 56 (13.4%) had cavitary pulmonary disease, and 6.2% (n = 26) had diabetes. The overall 5-year rate of TB recurrence in this study for the patients receiving the standard 6-month regimen was 2.9% (12/418). Moreover, almost half of the recurrent cases (41.7%; n = 5) were seen during the first year of the follow-up period. Some patient groups with risk factors recorded a higher recurrence rate, including patients with diabetes (15.4%), non-compliant patients (14.3%), pre-treatment lung cavitation patients (8.9%), illiterate patients (7.8%), and underweight patients (5.1%). In conclusion, the overall TB recurrence rate with the standard 6-month regimen was lower than that with the previous TB regimens. However, more efforts are needed to decrease TB recurrence rates further and achieve a durable cure for TB. In addition, healthcare professionals and TB control programs should consider potential risk factors of recurrence and address them to provide optimal care.

Sex differences in the impact of diabetes mellitus on tuberculosis recurrence: a retrospective national cohort study

OBJECTIVES

Whether diabetes mellitus (DM) increases tuberculosis (TB) recurrence risk is debatable. We determined the effect of DM on TB recurrence.

METHODS

This retrospective nationwide cohort study included patients with TB who successfully completed TB treatment during 2011-2017 and were followed up for TB recurrence until August 2020. We performed subdistribution hazard model analyses stratified by sex to assess DM risk related to TB recurrence after successful treatment.

RESULTS

Of 199,571 participants who had received successful TB treatment, 47,952 (24%) had DM. There were more men (64.4%), positive acid-fast bacilli smears (35.9%), and positive cultures (49.5%) in the DM group. There were 6208 (3.1%) TB recurrences during 5.1 years of follow-up: 38.9% and 26.6% occurred 1 and 1-2 years after treatment completion, respectively. The recurrence rate was higher in the DM group (3.8%) than in the non-DM group (2.9%, P <0.0001). DM was associated with a higher TB recurrence risk, especially in men (adjusted hazard ratio 1.23, 95% confidence interval 1.15-1.32) but not in women (adjusted hazard ratio 0.96, 95% confidence interval 0.85-1.09).

CONCLUSION

The TB recurrence rate after successful treatment was higher in patients with DM than in patients without DM. DM is associated with TB recurrence in men.

The socio-demographic, clinical characteristics and outcomes of tuberculosis among HIV infected adults in Lithuania: A thirteen-year analysis

BACKGROUND

Tuberculosis (TB) is a public health problem in Lithuania, among the 18 high-priority TB countries in the European region, and the most common AIDS-indicative disease with the highest proportion in the EU/EEA since 2015. The study aimed to identify socio-demographic, clinical characteristics and their relationship with TB outcomes in TB-HIV co-infected patients in Lithuania.

METHODS

A retrospective chart review analysed the characteristics of TB-HIV co-infected adults registered in State Information System of Tuberculosis over 2008-2020. The factors associated with drug-resistant TB and unsuccessful treatment outcome were identified by multivariable logistic regression.

RESULTS

The study included 345 cases in 311 patients (239 new, 106 previously treated cases), median age 40 years (IQR 35-45), 80.7% male. 67.8% patients knew their HIV-positive status before TB diagnosis, median time to TB diagnosis was 8 years (IQR 4-12). 83.6% were unemployed, 50.5%-anytime intravenous drug users (IDU), 34.9% abused alcohol. Drug-resistant TB rates in new and previously treated TB cases were 38.1% and 61.3%, respectively. In multivariable analysis, higher risk of drug-resistant TB was associated with imprisonment in new (aOR 3.35; 95%CI 1.17-9.57) and previously treated (aOR 6.63; 95%CI 1.09-40.35) cases. In 52.3% of new TB cases and in 42.5% previously treated TB cases the treatment outcomes were unsuccessful. In multivariable analysis of new TB cases, current imprisonment (aOR 2.77; 95%CI 1.29-5.91) and drug-resistant TB (aOR 2.18; 95%CI 1.11-4.28) were associated with unsuccessful treatment outcome. In multivariable analysis of previously treated TB cases, female gender (aOR 11.93; 95%CI 1.86-76.69), alcohol abuse (aOR 3.17; 95%CI 1.05-9.58), drug-resistant TB (aOR 4.83; 95%CI 1.53-15.28) were associated with unsuccessful treatment outcome.

CONCLUSIONS

In the TB-HIV-infected adult cohort in Lithuania, unemployment, imprisonment, IDU, alcohol abuse, known to be risk factors for TB, were very frequent. Drug resistance was an undeniable risk factor for unsuccessful treatment outcome and imprisonment was associated with drug resistant TB.