Long-Term Mortality of Tuberculosis Survivors in Korea: A Population-based Longitudinal Study

Comprehensive risk assessment for pulmonary manifestations in systemic lupus erythematosus: a large-scale Korean population-based longitudinal study

OBJECTIVES

Pulmonary involvement is common in systemic lupus erythematosus (SLE), but the relative risk of pulmonary manifestations in SLE versus non-SLE subjects remains unclear. This study aimed to evaluate the risk of pulmonary manifestations in SLE subjects compared with matched controls.

METHODS

Using data from the Korean National Health Insurance Service (2009-2017), we identified 6074 individuals aged ≥20 years with newly diagnosed SLE and 60 740 matched controls by age and sex (1:10 ratio) who did not have prior pulmonary manifestations.

RESULTS

Over a mean follow-up of 9.3±2.7 years, the incidence of pulmonary manifestations was 15.2 per 1000 person-years in the SLE cohort and 4.5 per 1000 person-years in the matched cohort. The SLE cohort had a significantly higher risk of pulmonary manifestations (adjusted HR (aHR) 3.26; 95% CI 2.99 to 3.56). The highest risk was observed for pulmonary hypertension (aHR 14.66; 95% CI 9.43 to 22.80), followed by interstitial lung disease (aHR 9.58; 95% CI 7.99 to 11.49), pleural disorders (aHR 3.29; 95% CI 2.84 to 3.81), pulmonary embolism (aHR 2.66; 95% CI 2.06 to 3.43), tuberculosis (aHR 2.35; 95% CI 1.88 to 2.93), acute respiratory distress syndrome and haemorrhage (aHR 1.85; 95% CI 1.51 to 2.25) and lung cancer (aHR 1.41; 95% CI 1.02 to 1.95).

CONCLUSIONS

Subjects with SLE have an approximately 3.3-fold higher risk of pulmonary manifestations compared with matched controls. Notably, the risks of pulmonary hypertension and interstitial lung disease are particularly elevated.

COVID-19 and risk of long-term mortality in COPD: a nationwide population-based cohort study

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a risk factor for severe COVID-19. However, mortality after COVID-19 recovery in this population remains unclear.

METHODS

We retrospectively enrolled individuals with COPD from the Korean National Health Insurance database. We compared the mortality rate in individuals with COPD who recovered from COVID-19 between 8 October 2020 and 31 December 2021 (COVID-19 cohort, n=2499) with that in 1:1 propensity score-matched controls (n=2499). The study population was followed until either death or 30 September 2022, whichever came first.

RESULTS

The COVID-19 cohort had a 4.8% mortality rate vs 2.7% in matched controls during a median follow-up of 319 days (IQR, 293-422 days), including 14 days of recovery time. The COVID-19 cohort had a higher risk of death than matched controls (adjusted HR (aHR)=1.81, 95% CI=1.35 to 2.45). The risk of mortality was notably higher in individuals with severe COVID-19 (aHR=5.05, 95% CI=3.65 to 6.97), especially during the first 180 days of recovery (highest during the first 30 days (aHR=20.25, 95% CI=7.79 to 52.64)). Non-severe COVID-19 does not increase the risk of mortality compared with controls (aHR=0.85, 95% CI=0.57 to 1.28).

CONCLUSION

Individuals with COPD recovering from COVID-19 showed an increased risk of long-term mortality, particularly within the first 180 days post-recovery, especially those who experienced severe COVID-19.

Association between rheumatoid arthritis and interstitial lung disease and impact of serologic status: a large-scale longitudinal study

Interstitial lung disease (ILD) leads to worse outcomes in subjects with rheumatoid arthritis (RA). Few large-scale longitudinal studies have provided comprehensive data on the incidence and risk of ILD in RA compared with non-RA populations. We compare the risk of incident ILD in subjects with RA and matched controls, while also evaluating the impact of RA serologic status. Using the Korean National Health Insurance Service Data between 2010 and 2017, we identified 52,325 individuals with RA and 261,625 without RA. During a median follow-up period of 4.4 years, 3.7% of the RA cohort and 0.5% of the matched cohort developed ILD, with incidence rates of 8.30 and 1.01 per 1,000 person-years. Compared to controls, the risk of incident ILD was significantly higher in the RA cohort (adjusted hazard ratio [aHR] 7.84 [7.29-8.44]), and seropositive and seronegative RA exhibited aHRs of 9.00 (8.34-9.72) and 4.81 (4.25-5.44). Although the risk of ILD was higher in seropositive RA than seronegative RA, the risk of developing ILD was also higher in subjects with seronegative RA than in matched controls, suggesting that close monitoring for ILD should be performed in this population.

COVID-19 and Long-term Risk of Ischemic Heart Disease in Asthma

Despite the importance of comorbid ischemic heart disease (IHD) in the prognosis of asthma, the long-term impact of coronavirus disease 2019 (COVID-19) on IHD in adults with asthma remains unclear. This study investigated the long-term effects of COVID-19 on the risk of IHD in individuals with asthma, particularly regarding COVID-19 severity. Using the Korean National Health Insurance Service claims database, we identified individuals with asthma who had recovered from COVID-19 between October 8, 2020, and December 31, 2021 (n = 8,011) and 1:1 propensity score-matched controls (n = 8,011). The incidence and risk of IHD were compared between the two groups. Overall, during a median follow-up of 95 days (interquartile range, 34-213 days; range, 1-448 days), which includes a median of 14 lag days, the COVID-19 cohort did not show a higher risk of IHD (hazard ratio [HR], 2.11; 95% confidence interval [CI], 0.99-4.48) compared to matched controls. However, when the severity of COVID-19 was considered, the severe COVID-19 cohort exhibited a higher risk of IHD (HR, 4.89; 95% CI, 1.86-12.84) than matched controls; in contrast, the non-severe COVID-19 cohort showed no significantly increased risk of IHD (HR, 1.64; 95% CI, 0.73-3.70). Severe COVID-19 is associated with an increased long-term risk of IHD in adults with asthma, emphasizing the importance of cardiovascular events monitoring to improve asthma treatment outcomes in the era of COVID-19.

Association between metabolic syndrome and chronic obstructive pulmonary disease development in young individuals: a nationwide cohort study

BACKGROUND

The association between metabolic syndrome (MetS) and chronic obstructive pulmonary disease (COPD) has not been studied well, particularly in young individuals. We investigated the risk of COPD development in young individuals based on MetS and its components.

METHODS

We used the Korean National Health Information Database to identify 6,891,400 individuals aged 20-39 years who participated in the national health check-up service between 2009 and 2012. Then, we identified individuals with MetS and investigated COPD development based on health insurance claims. Cox proportional hazard regression models were used to calculate the adjusted hazard ratio (aHR) for the risk of COPD development.

RESULTS

During a mean follow-up period of 8.35 years, 13,784 individuals were newly diagnosed with COPD. MetS was associated with an increased risk of COPD (aHR, 1.18; 95% confidence interval [CI], 1.11-1.24). Among the MetS components, except for hyperglycemia, abdominal obesity (aHR, 1.27; 95% CI, 1.19-1.34), hypertension (aHR, 1.05; 95% CI, 1.01-1.10), hypertriglyceridemia (aHR, 1.11; 95% CI, 1.07-1.16), and low high-density lipoprotein cholesterol levels (aHR, 1.16; 95% CI, 1.11-1.22) were significantly associated with COPD development. A higher number of MetS components correlated with an increased risk of COPD development, with the highest risk observed when all five MetS components were present (aHR, 1.55; 95% CI, 1.28-1.87).

CONCLUSION

MetS was associated with COPD development in young individuals. The risk of COPD development increased along with the increasing number of MetS components. These findings suggest that careful monitoring for COPD development is necessary in young individuals with MetS, especially those with multiple components of MetS.

Mortality Rates after Tuberculosis Treatment, Georgia, USA, 2008-2019

Limited data exist on mortality rates after tuberculosis (TB) treatment in the United States. We analyzed mortality rates for all adults in Georgia, USA, who had a TB diagnosis and finished treatment during January 1, 2008-December 31, 2019. We obtained posttreatment mortality rate data from the National Death Index and calculated standardized mortality ratios (SMRs) for TB treatment survivors and the general Georgia population. Among 3,182 TB treatment survivors, 233 (7.3%) had died as of December 31, 2019. The overall TB cohort age- and sex-adjusted SMR was 0.89 (95% CI 0.73-1.05). The SMR among US-born TB treatment survivors was 1.56 (95% CI 1.36-1.77). In the TB cohort, US-born status, HIV co-infection, excess alcohol use, diabetes mellitus, and end-stage renal disease were associated with increased risk for death after TB treatment. TB treatment survivors could benefit from improved linkage to primary and HIV comprehensive care to prevent posttreatment death.

Proposed Etiotypes for Chronic Obstructive Pulmonary Disease: Controversial Issues

The 2023 Global Initiative for Chronic Obstructive Lung Disease (GOLD) revised the definition of chronic obstructive pulmonary disease (COPD) to broadly include a variety of etiologies. A new taxonomy, composed of etiotypes, aims to highlight the heterogeneity in causes and pathogenesis of COPD, allowing more personalized management strategies and emphasizing the need for targeted research to understand and manage COPD better. However, controversy arises with including some diseases under the umbrella term of COPD, as their clinical presentations and treatments differ from classical COPD, which is smoking-related. COPD due to infection (COPD-I) and COPD due to environmental exposure (COPD-P) are classifications within the new taxonomy. Some disease entities in these categories show distinct clinical features and may not benefit from conventional COPD treatments, raising questions about their classification as COPD subtypes. There is also controversy regarding whether bronchiectasis with airflow limitations should be classified as an etiotype of COPD. This article discusses controversial issues associated with the proposed etiotypes for COPD in terms of COPD-I, COPD-P, and bronchiectasis. While the updated COPD definition by GOLD 2023 is a major step towards recognizing the disease's complexity, it also raises questions about the classification of related respiratory conditions. This highlights the need for further research to improve our understanding and approach to COPD management.

Bronchiectasis in Asia: a review of current status and challenges

Recent bronchiectasis studies from large-scale multinational, multicentre registries have demonstrated that the characteristics of the disease vary according to geographic region. However, most perspectives on bronchiectasis are dominated by data from Western countries. This review intends to provide an Asian perspective on the disease, focusing on the established registries in India, Korea and China. Asian patients with bronchiectasis are less likely to show female predominance and experience exacerbations, are more likely to be younger, have milder disease, and have fewer options for guideline-recommended treatment than those living in other global regions. Furthermore, Asian bronchiectasis patients demonstrate different comorbidities, microbiological profiles and unique endophenotypes, including post-tuberculosis and dry bronchiectasis. Notably, each Asian region reveals further geographic variations and inter-patient differences. Future studies are warranted to better characterise Asian patients with bronchiectasis.

Long-Term Impacts of COVID-19 on Severe Exacerbation and Mortality in Adult Asthma: A Nationwide Population-Based Cohort Study

BACKGROUND

In adults with asthma, the long-term impact of previous coronavirus disease 2019 (COVID-19) on severe exacerbations and mortality is unclear.

OBJECTIVE

We evaluated the long-term risk of severe exacerbation and mortality in adults with asthma who recovered from COVID-19.

METHODS

Using the Korean National Health Insurance claim-based database, we compared the risk of severe exacerbations (emergency room visits or hospitalization) and mortality in adults with asthma aged greater than 20 years who had recovered from COVID-19 between October 8, 2020, and December 16, 2021 (COVID-19 cohort, n = 10,739) with 1:1 propensity score-matched controls (n = 10,739).

RESULTS

During a median follow-up of 87 days (range, 15-448 days), the incidence rate of severe exacerbations in the COVID-19 cohort and the matched cohort was 187.3 and 119.3 per 10,000 person-years, respectively. The COVID-19 cohort had a higher risk of severe exacerbation compared with the matched cohort (hazard ratio = 1.57; 95% CI, 1.06-2.32). During a median follow-up of 360 days (range, 15-721 days), the incidence rate of death in the COVID-19 and matched cohorts was 128.3 and 73.5 per 10,000 person-years, respectively. The COVID-19 cohort had a higher risk of death (hazard ratio = 1.76; 95% CI, 1.33-2.30) compared with the matched cohort. When further analyzed by COVID-19 severity, severe COVID-19 was associated with a 5.12-fold (95% CI, 3.27-8.01) and 7.31-fold (95% CI, 5.41-9.88) increased risk of severe exacerbation and death, respectively, but non-severe COVID-19 was not.

CONCLUSIONS

Our study shows that severe COVID-19 is associated with an increased long-term risk of severe exacerbation and mortality among individuals with asthma.

Impact of Rheumatoid Arthritis and Seropositivity on the Risk of Non-Cystic Fibrosis Bronchiectasis

BACKGROUND

Despite the coexistence of bronchiectasis and rheumatoid arthritis (RA) and the poor prognosis associated with the combination of conditions, to our knowledge, no longitudinal studies that comprehensively evaluated whether patients with RA have a higher risk of bronchiectasis compared with those without RA have been published. Whether seropositivity is associated with an increased risk of bronchiectasis in RA is the subject of ongoing controversy.

RESEARCH QUESTION

Does RA influence the development of bronchiectasis? Is seropositivity associated with an increased risk of bronchiectasis in RA?

STUDY DESIGN AND METHODS

The incidence of bronchiectasis was compared between individuals with RA (n = 50,651; seropositive rheumatoid arthritis [SPRA]: n = 35,879 and seronegative rheumatoid arthritis [SNRA]: n = 14,772) and 1:5 age- and sex-matched control patients (n = 253,255) enrolled between 2010 and 2017 in the Korean National Health Insurance Service database. The participants were followed from 1 year after RA diagnosis or the corresponding index date to the date of bronchiectasis incidence, censored date, or December 2019.

RESULTS

The cumulative incidence of bronchiectasis at 9 years of follow-up was approximately 7% in participants with RA. During a median follow-up of 4.3 years (interquartile range, 2.6-6.3 years), participants with RA showed a 2.12-fold higher risk of developing bronchiectasis than matched control participants, even after adjusting for potential confounders related to bronchiectasis development (95% CI, 2.00-2.25). In an analysis of RA serologic status using a fully adjusted model, participants with SPRA and those with SNRA showed 2.34-fold (95% CI, 2.20-2.49) and 1.56-fold (95% CI, 1.40-1.73) increased risks, respectively, compared with matched control participants.

INTERPRETATION

Individuals with RA had approximately twice the risk of developing bronchiectasis than matched control individuals, even after adjusting for potential confounders. The increased risk was more evident in individuals with SPRA than in those with SNRA, implying that rheumatic inflammation plays a major role in the development of RA-bronchiectasis overlap.

Tuberculosis and osteoporotic fracture risk: development of individualized fracture risk estimation prediction model using a nationwide cohort study

Purpose

Tuberculosis (TB) is linked to sustained inflammation even after treatment, and fracture risk is higher in TB survivors than in the general population. However, no individualized fracture risk prediction model exists for TB survivors. We aimed to estimate fracture risk, identify fracture-related factors, and develop an individualized risk prediction model for TB survivors.

Methods

TB survivors (n = 44,453) between 2010 and 2017 and 1:1 age- and sex-matched controls were enrolled. One year after TB diagnosis, the participants were followed-up until the date of fracture, death, or end of the study period (December 2018). Cox proportional hazard regression analyses were performed to compare the fracture risk between TB survivors and controls and to identify fracture-related factors among TB survivors.

Results

During median 3.4 (interquartile range, 1.6-5.3) follow-up years, the incident fracture rate was significantly higher in TB survivors than in the matched controls (19.3 vs. 14.6 per 1,000 person-years, p < 0.001). Even after adjusting for potential confounders, TB survivors had a higher risk for all fractures (adjusted hazard ratio 1.27 [95% confidence interval 1.20-1.34]), including hip (1.65 [1.39-1.96]) and vertebral (1.35 [1.25-1.46]) fractures, than matched controls. Fracture-related factors included pulmonary TB, female sex, older age, heavy alcohol consumption, reduced exercise, and a higher Charlson Comorbidity Index (p < 0.05). The individualized fracture risk model showed good discrimination (concordance statistic = 0.678).

Conclusion

TB survivors have a higher fracture risk than matched controls. An individualized prediction model may help prevent fractures in TB survivors, especially in high-risk groups.

Increased Risk of Incident Chronic Obstructive Pulmonary Disease and Related Hospitalizations in Tuberculosis Survivors: A Population-Based Matched Cohort Study

BACKGROUND

Tuberculosis (TB) survivors have an increased risk of developing chronic obstructive pulmonary disease (COPD). This study assessed the risk of COPD development and COPD-related hospitalization in TB survivors compared to controls.

METHODS

We conducted a population-based cohort study of TB survivors and 1:1 age- and sex-matched controls using data from the Korean National Health Insurance Service database collected from 2010 to 2017. We compared the risk of COPD development and COPD-related hospitalization between TB survivors and controls.

RESULTS

Of the subjects, 9.6% developed COPD, and 2.8% experienced COPD-related hospitalization. TB survivors had significantly higher COPD incidence rates (36.7/1,000 vs. 18.8/1,000 person-years, P < 0.001) and COPD-related hospitalization (10.7/1,000 vs. 4.3/1,000 person-years, P < 0.001) than controls. Multivariable Cox regression analyses revealed higher risks of COPD development (adjusted hazard ratio [aHR], 1.63; 95% confidence interval [CI], 1.54-1.73) and COPD-related hospitalization (aHR, 2.03; 95% CI, 1.81-2.27) in TB survivors. Among those who developed COPD, the hospitalization rate was higher in individuals with post-TB COPD compared to those with non-TB COPD (10.7/1,000 vs. 4.9/1,000 person-years, P < 0.001), showing an increased risk of COPD-related hospitalization (aHR, 1.84; 95% CI, 1.17-2.92).

CONCLUSION

TB survivors had higher risks of incident COPD and COPD-related hospitalization compared to controls. These results suggest that previous TB is an important COPD etiology associated with COPD-related hospitalization.

Long term management of people with post-tuberculosis lung disease

Post-tuberculosis lung disease (PTLD) is emerging as a significant area of global interest. As the number of patients surviving tuberculosis (TB) increases, the subsequent long-term repercussions have drawn increased attention due to their profound clinical and socioeconomic impacts. A primary obstacle to its comprehensive study has been its marked heterogeneity. The disease presents a spectrum of clinical manifestations which encompass tracheobronchial stenosis, bronchiectasis, granulomas with fibrosis, cavitation with associated aspergillosis, chronic pleural diseases, and small airway diseases-all persistent consequences of PTLD. The spectrum of symptoms a patient may experience varies based on the severity of the initial infection and the efficacy of the treatment received. As a result, the long-term management of PTLD necessitates a detailed and specific approach, addressing each manifestation individually-a tailored strategy. In the immediate aftermath (0-12 months after anti-TB chemotherapy), there should be an emphasis on monitoring for relapse, tracheobronchial stenosis, and smoking cessation. Subsequent management should focus on addressing hemoptysis, managing infection including aspergillosis, and TB-associated chronic obstructive pulmonary disease or restrictive lung function. There remains a vast expanse of knowledge to be discovered in PTLD. This review emphasizes the pressing need for comprehensive, consolidated guidelines for management of patients with PTLD.

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.

Increased Lung Cancer Risk and Associated Risk Factors in Tuberculosis Survivors: A Korean Population-Based Study

BACKGROUND

Few studies have comprehensively evaluated the risk of lung cancer in tuberculosis survivors with consideration of smoking status and chronic obstructive pulmonary disease (COPD). Furthermore, little is known about lung cancer risk factors in tuberculosis survivors.

METHODS

This population-based cohort study enrolled tuberculosis survivors (n = 75 467) between 2010 and 2017 and 1:1 age- and sex-matched controls. Subjects were followed up for 1 year from the date of tuberculosis diagnosis to the date of the incident lung cancer, death, or December 2018, whichever came first. The risk of lung cancer was evaluated according to smoking and COPD status. We also evaluated the risk factors for lung cancer and developed an individualized lung cancer prediction model for tuberculosis survivors.

RESULTS

During a median follow-up duration of 4.8 years, the incident lung cancer risk was 1.72-fold higher in tuberculosis survivors than in the controls. Among tuberculosis survivors, those who were current smokers with ≥20 pack-years showed the highest risk of lung cancer (adjusted hazard ratio, 6.78) compared with never-smoker, non-tuberculosis-infected controls. tuberculosis survivors with COPD had a higher risk (2.43) than non-COPD, non-tuberculosis-infected controls. Risk factors for lung cancer in tuberculosis survivors were pulmonary tuberculosis, age >60 years, smoking, and the presence of COPD or asthma. The individualized lung cancer risk model showed good discrimination (concordance statistic = 0.827).

CONCLUSIONS

Previous tuberculosis infection is an independent risk factor regardless of smoking status or amount and COPD. Closer monitoring of tuberculosis survivors, especially heavy smokers or those with COPD, is needed for early lung cancer diagnosis.

Systemic sclerosis and risk of bronchiectasis: a nationwide longitudinal cohort study

BACKGROUND

The association between systemic sclerosis and the development of bronchiectasis is unclear. This study aimed to compare the risk of bronchiectasis between individuals with systemic sclerosis and those without using a nationwide longitudinal dataset.

METHODS

Using the Korean National Health Insurance Service dataset between 2010 and 2017, we identified 4845 individuals aged ≥ 20 years with systemic sclerosis and 24,225 without systemic sclerosis who were matched 1:5 by age and sex. They were followed up until the date of a bronchiectasis diagnosis, death, or December 31, 2019, whichever came first.

RESULTS

During a median follow-up period of 6.0 (interquartile range, 3.2-8.7) years, 5.3% of the systemic sclerosis cohort and 1.9% of the matched cohort developed bronchiectasis, with incidence rates of 9.99 and 3.23 per 1000 person-years, respectively. Even after adjusting for potential confounders, the risk of incident bronchiectasis was significantly higher in the systemic sclerosis cohort than in the matched cohort (adjusted hazard ratio 2.63, 95% confidence interval 2.22-3.12). A subgroup analysis of individuals with systemic sclerosis revealed that the risk of incident bronchiectasis was notably higher in younger individuals aged 20-39 years (P for interaction = 0.048) and in those without other coexisting connective tissue diseases (P for interaction = 0.006) than in their counterparts.

CONCLUSIONS

The risk of incident bronchiectasis is higher in individuals with systemic sclerosis than those without. Bronchiectasis should be considered one of the pulmonary manifestations related to systemic sclerosis.

Impact of air pollution on healthcare utilization in patients with bronchiectasis

Introduction

Air pollutants are increasingly recognized to affect long-term outcomes in patients with bronchiectasis. We aimed to figure out the association between air pollutants and the risk of healthcare utilization in patients with bronchiectasis.

Methods

Data for 1,029 subjects with bronchiectasis in Seoul were extracted. The air pollutants included particulate matter of 10 μm or less in diameter (PM10), particulate matter of 2.5 μm or less in diameter (PM2.5), sulfur dioxide (SO2), carbon monoxide (CO), ozone (O3), and nitrogen dioxide (NO2). The outcome was all-cause healthcare uses, defined as outpatient visit, emergency department visit, or hospitalization. The concentration-response curves between each air pollutant and relative risks for healthcare utilization were obtained.

Results

There were significant correlations between air pollutant concentrations and the risk of healthcare utilization, particularly for PM10, NO2, SO2, and CO. This risk was observed even at concentrations below the recommended safe thresholds for the general population. The slopes for the association between PM10 and NO2 and the risk of healthcare use showed a logarithmic growth pattern, with the steepest increase up to 30 μg/m3 and 0.030 parts per million (ppm), respectively. The curves for SO2 and CO showed an inverted U-shaped pattern, with a peak at 0.0045 ppm and a slow upward curve, respectively. No specific trends were observed for PM2.5 and O3 and the risk of healthcare use.

Discussion

Increased concentrations of PM10, NO2, SO2, and CO were associated with increased healthcare utilization in patients with bronchiectasis. For patients with bronchiectasis, there were no safety thresholds for those air pollutants, and even low levels of air pollutant exposure can negatively impact bronchiectasis outcomes.

Effects of underweight and overweight on mortality in patients with pulmonary tuberculosis

Background

Poor nutrition increases disease severity and mortality in patients with tuberculosis (TB). There are gaps in our understanding of the effects of being underweight or overweight on TB in relation to sex.

Methods

We generated a nationwide TB registry database and assessed the effects of body mass index (BMI) on mortality in patients with pulmonary TB. The cause of death was further classified as TB-related or non-TB-related deaths. First, logistic regression analysis was performed to assess the association between BMI (a continuous variable) and mortality, and subgroup analyses of the multivariable logistic regression model were performed separately in male and female patients. Second, we categorized BMI into three groups: underweight, normal weight, and overweight, and assessed the impact of being underweight or overweight on mortality with reference to normal weight.

Results

Among 9,721 patients with pulmonary TB, the mean BMI was 21.3 ± 3.4; 1,927 (19.8%) were underweight, and 2,829 (29.1%) were overweight. In multivariable logistic regression analysis, mortality was significantly increased with the decrement of BMI (adjusted odds ratio [aOR] = 0.893, 95% confidence interval [CI] = 0.875-0.911). In subgroup analyses, underweight patients had significantly higher odds of mortality, especially TB-related deaths (aOR = 2.057, 95% CI = 1.546-2.735). The association with mortality and male patients was higher (aOR = 2.078, 95% CI = 1.717-2.514), compared with female patients (aOR = 1.724, 95% CI = 1.332-2.231). Being overweight had a significant protective effect against TB-related death only in females (aOR = 0.500, 95% CI = 0.268-0.934), whereas its effect on non-TB-related death was observed only in males (aOR = 0.739, 95% CI = 0.587-0.930).

Conclusion

Being underweight was linked to high mortality, whereas being overweight had beneficial effects in patients with pulmonary TB.

Diabetes severity is strongly associated with the risk of active tuberculosis in people with type 2 diabetes: a nationwide cohort study with a 6-year follow-up

BACKGROUND

Many have the rising coincidence of diabetes mellitus (DM) and endemic tuberculosis (TB). We evaluated whether the severity of diabetes is associated with an increased risk of active TB infection.

METHODS

 Using a nationally representative database from the Korean National Health Insurance System, 2, 489, 718 people with type 2 DM who underwent a regular health checkup during 2009-2012 were followed up until the end of 2018. The diabetes severity score parameters included the number of oral hypoglycemic agents (≥ 3), insulin use, diabetes duration (≥ 5 years), and the presence of chronic kidney disease (CKD) or cardiovascular disease. Each of these characteristics was scored as one point, and their sum (0-5) was used as the diabetes severity score.

RESULTS

We identified 21, 231 cases of active TB during a median follow-up of 6.8 years. Each parameter of the diabetes severity score was associated with an increased risk of active TB (all P < 0.001). Insulin use was the most significant factor related to the risk of TB, followed by CKD. The risk of TB increased progressively with increasing diabetes severity score. After adjusting for possible confounding factors, the hazard ratio (95% confidence interval) for TB were 1.23 (1.19-1.27) in participants with one parameter, 1.39 (1.33-1.44) in those with two parameters, 1.65 (1.56-1.73) in those with three parameters, 2.05 (1.88-2.23) in those with four parameters, and 2.62 (2.10-3.27) in those with five parameters compared with participants with no parameters.

CONCLUSION

Diabetes severity was strongly associated in a dose-dependent manner with the occurrence of active TB. People with a higher diabetes severity score may be a targeted group for active TB screening.

Association between exercise and risk of cardiovascular diseases in patients with non-cystic fibrosis bronchiectasis

BACKGROUND

Although cardiovascular comorbidities negatively impact survival in patients with bronchiectasis, there is limited evidence to recommend exercise in this population. We aimed to evaluate whether exercise habit changes are related to reduced cardiovascular disease risk and explore an optimal exercise amount.

METHODS

This study identified 165,842 patients with newly diagnosed bronchiectasis during 2010-2016 who underwent two health examinations and were followed up until December 2020. The exposure was the change in weekly habits of moderate- or vigorous-intensity physical activity between the two examinations, classified into non-exercisers and exercisers (further classified into new exercisers, exercise dropouts, and exercise maintainers). The amount of exercise was measured using metabolic equivalents of task (MET). The outcome was the incidence of myocardial infarction (MI) or stroke.

RESULTS

During a mean of 6.2 ± 2.1 follow-up years, 4,233 (2.6%) and 3,745 (2.3%) of patients with bronchiectasis had MI or stroke, respectively. Compared to non-exercisers, exercisers had a significantly lower risk of MI or stroke by 9-28% (p < 0.001 for both). Among exercisers, exercise maintainers showed the lowest risk of MI (adjusted hazard ratio [aHR], 0.72; 95% confidence interval [CI], 0.64-0.81) and stroke (aHR, 0.72; 95% CI, 0.64-0.82) compared to non-exercisers. Regarding exercise amount, a significant risk reduction was observed only in patients with bronchiectasis who exercised for ≥ 500 MET-min/wk.

CONCLUSION

Exercise was associated with a reduced risk of cardiovascular diseases in patients with bronchiectasis. In particular, the risk was lowest in exercise maintainers, and cardiovascular risk reduction was significant when exercising more than 500 MET-min/wk.