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

Air Pollution Increases Healthcare Utilization Below Safe Thresholds in Individuals With Asthma

PURPOSE

Safety thresholds for air quality levels have been proposed to protect people from the harmful effects of air pollutants. However, the impacts of air pollutants on asthma, particularly at levels below these safe thresholds, remain unclear.

METHODS

We analyzed the associations between air pollutants (particulate matter of 10 μm or less in diameter [PM₁₀], particulate matter of 2.5 μm or less in diameter, sulfur dioxide [SO₂], carbon monoxide, ozone [O₃], and nitrogen dioxide) and healthcare utilization in 23,498 individuals with asthma in Seoul during the 2015-2017 season. The relative risk for healthcare utilization was assessed based on quantitative comparison (upper quartile vs. lower quartile) and non-linear concentration-response curves. Safety thresholds for air quality levels were determined according to the World Health Organization and Korean standards.

RESULTS

In quantitative analysis, healthcare utilization risk decreased for PM₁₀ and SO₂ but increased for O₃ on lag day 0, with no significant associations observed for other air pollutants. Non-linear analyses revealed significant concentration-response associations for all air pollutants, indicating increased risks of healthcare utilization on lag day 0. Notably, these increased risks occurred below proposed safety thresholds, with a steeper rise observed for asthma-related healthcare utilization within these ranges.

CONCLUSIONS

Exposure to 6 air pollutants was associated with an increased risk of healthcare utilization among individuals with asthma, with no safe exposure levels identified. The impact was more pronounced below current safety thresholds.

Risk of acute exacerbation of chronic obstructive pulmonary disease after COVID-19 recovery: a nationwide population-based cohort study

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is associated with severe Coronavirus disease 2019 (COVID-19) outcomes. However, it is uncertain whether the risk of acute exacerbation of COPD (AECOPD) increases after recovering from COVID-19.

METHODS

This study included 2,118 individuals with COPD from the Korea National Health Insurance Service database who were also diagnosed with COVID-19. Matched controls were chosen using 1:1 propensity score (PS) matching. We compared the risk of AECOPD after COVID-19 recovery between the COVID-19 cohort and matched controls between October 8, 2020, and December 31, 2021, using PS-matched Cox proportional hazard regression models.

RESULTS

During a median follow-up of 62 days (interquartile range, 29-179 days), including a median of 14 days of recovery time after COVID-19, 68 people (5.6%) in the COVID-19 cohort and 50 (3.9%) in the matched control group experienced AECOPD. Compared to the matched controls, the COVID-19 cohort had a significantly higher risk of overall AECOPD (hazard ratio [HR] = 1.45, 95% confidence interval [CI] = 1.09-1.92). This increased risk was particularly evident for severe AECOPD among individuals who had severe COVID-19 within the first 30days post-recovery (aHR = 8.14, 95% CI = 3.32-19.97). When classified by COVID-19 severity, while severe COVID-19 significantly increased this risk (aHR = 2.97, 95% CI = 2.15-4.11), non-severe COVID did not significantly influence the risk of AECOPD, regardless of time duration or exacerbation severity.

CONCLUSION

Individuals with COPD who had severe COVID-19 have increased risk of AECOPD after COVID-19 recovery, especially within the first 30 days after COVID-19 recovery.

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.

Risk of incident chronic obstructive pulmonary disease during longitudinal follow-up in patients with nontuberculous mycobacterial pulmonary disease

BACKGROUND

The Global Initiative for Chronic Obstructive Lung Disease 2023 revision proposed that chronic obstructive pulmonary disease (COPD) has various etiologies including infections (COPD-I), such as tuberculosis and human immunodeficiency virus. While nontuberculous mycobacterial pulmonary disease (NTM-PD) and pulmonary tuberculosis share similar clinical manifestations, research on COPD development during longitudinal follow-up in patients with NTM-PD is limited. In this study, we aimed to evaluate the incidence and risk of COPD development in patients with NTM-PD.

METHODS

We retrospectively enrolled patients with NTM-PD with normal lung function and 1:4 age-, sex-, body mass index-, and smoking status-matched controls between November 1994 and January 2022. We compared the risks of spirometry-defined COPD between the NTM-PD and control groups (study 1). A nationwide cohort study using the health insurance claims database was conducted to validate the findings (study 2).

RESULTS

In study 1, during a mean follow-up of 3.3 years, COPD occurred in 14.0% (241/1,715) and 4.3% (293/6,860) of individuals in the NTM-PD and matched control cohorts, respectively. The NTM-PD cohort exhibited a higher risk of incident COPD (adjusted hazard ratio [aHR], 2.57; 95% CI, 2.15-3.09) compared to matched controls. In study 2, COPD occurred in 6.2% (24/386) and 2.5% (28/1,133) of individuals with and without NTM-PD, respectively. The NTM-PD cohort had a higher risk of incident COPD (aHR, 2.04; 95% CI, 1.21-3.42) compared to matched controls.

CONCLUSION

These findings suggest that NTM-PD could be considered a new etiotype of COPD-I and emphasize the importance of monitoring lung function in individuals with NTM-PD.