Dataset Information

Relationship between exposure to ozone and exacerbation requiring hospital admission among patients with asthma: a case-control study in central Taiwan.

ABSTRACT:

Objective

The convergence of asthma and air pollutants in ageing populations is currently a growing health issue worldwide, and hence there is an essential need to investigate the association between exposure to air pollution, particularly ozone (O₃), and exacerbation requiring admission in patients with asthma.

Setting

A case-control study at a tertiary referral hospital in central Taiwan.

Participants

We used an asthma cohort, which included 11 400 patients with asthma, for the period 2006-2018 at Taichung Veterans General Hospital.

Primary and secondary outcome measures

We identified patients who had admitted for exacerbation as cases and selected patients with asthma without exacerbation, matching (1:4) the cases for age, gender and season of exacerbation, as controls. Data on hourly level of air pollutants were obtained from the Taiwan Environmental Protection Administration. We used conditional logistic regression and calculated adjusted ORs (adjORs) with 95% CIs.

Results

We enrolled 11 400 participants with asthma, and 4.4% (501) of them had been admitted for exacerbation. Participants with asthma with exacerbation requiring hospitalisation were exposed to a higher level of O₃ 8-hour daily maximum (adjOR 1.009, 95% CI 1.001 to 1.016) and were more likely to have high Charlson Comorbidity Index (CCI ≥3; adjOR 2.198, 95% CI 1.729 to 2.794) and asthma-chronic obstructive pulmonary disease overlap (adjOR 4.542, 95% CI 3.376 to 6.611) compared with those without exacerbation. The aforementioned associations between exacerbation of asthma requiring hospitalisation and exposure to O₃ were similar when defined by either O₃ 1-hour daily maximum or O₃ 24-hour average. Moreover, the O₃ relevant exacerbation of asthma mainly existed in those aged older than 65 years and patients with medical comorbidities, including gastrointestinal diseases, cardiovascular diseases, neurological diseases, diabetes and renal disease.

Conclusions

Our findings highlight the need for vigilance of exposure to O₃ among elderly with asthma, particularly those with medical comorbidities. Further studies are warranted to investigate the underlying mechanisms.

SUBMITTER: Lin CH

PROVIDER: S-EPMC8845173 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Relationship between exposure to ozone and exacerbation requiring hospital admission among patients with asthma: a case-control study in central Taiwan.

Lin Ching-Heng CH Wong Li-Ting LT Hsu Jeng-Yuan JY Chao Wen-Cheng WC

BMJ open 20220214 2

<h4>Objective</h4>The convergence of asthma and air pollutants in ageing populations is currently a growing health issue worldwide, and hence there is an essential need to investigate the association between exposure to air pollution, particularly ozone (O<sub>3</sub>), and exacerbation requiring admission in patients with asthma.<h4>Setting</h4>A case-control study at a tertiary referral hospital in central Taiwan.<h4>Participants</h4>We used an asthma cohort, which included 11 400 patients wit ...[more]

PMID: 35165108

Similar Datasets

Project description:BackgroundThe relationships between short-term ozone exposure and the acute exacerbations of asthma in adults have not been fully studied. Existing studies commonly ignored the effects of ozone on mild or early asthma exacerbations.ObjectiveTo investigate the associations between short-term ozone exposure and asthma exacerbations in Chinese adults.MethodsWe administered health management for adult asthma patients through the Respiratory Home Platform and required them to monitor their lung function every morning and evening by themselves. Finally, a total of 4,467 patients in 18 Chinese cities were included in the current analyses, with 79,217 pairs of lung function records. The maximum daily 8-h average ozone concentrations were collected from fixed-site air quality monitoring stations. We calculated diurnal peak expiratory flow (PEF) variation using morning and evening measurements of PEF and then defined different severity of asthma exacerbations with diurnal PEF variations >10, 15, and 20%, respectively. A binomial distributed generalized additive mixture model combined with distribution non-linear models was applied to examine the association of ozone with asthma exacerbations. We further conducted stratified analyses by sex, age, season of lung function tests, and region.Measurements and resultsWe found that short-term ozone exposure was independently associated with an elevated risk of asthma exacerbations defined by lung function and the effects could last for about 2 days. At lag 0-2 days, each 10 μg/m3 increment in ozone concentration was associated with odds ratios of 1.010 [95% confidence interval (CI): 1.003, 1.017], 1.014 (95% CI: 1.005, 1.023), and 1.017 (95% CI: 1.006, 1.028) for asthma exacerbations that were defined by diurnal PEF variation over 10, 15, and 20%, respectively. The associations remained significant after adjusting for other pollutants, and became unstable when using 24-h average ozone concentration. We also found that the associations were relatively stronger in males, those aged 45 years and older, and in the warm season.ConclusionsOur results suggest that short-term ozone exposure can increase the risk of asthma exacerbations, even in the early stage of exacerbation. Male and older asthma patients may be more vulnerable to ozone air pollution, especially in the warm season.

Project description:Many studies have evaluated associations between asthma emergency department (ED) visits, hospital admissions (HAs), and ambient ozone (O3) across the US, but not in Texas. We investigated the relationship between O3 and asthma HAs, and the potential impacts of outdoor pollen, respiratory infection HAs, and the start of the school year in Texas.We obtained daily time-series data on asthma HAs and ambient O3 concentrations for Dallas, Houston, and Austin, Texas for the years 2003-2011. Relative risks (RRs) and 95% confidence intervals (CIs) of asthma HAs per 10-ppb increase in 8-h maximum O3 concentrations were estimated from Poisson generalized additive models and adjusted for temporal trends, meteorological factors, pollen, respiratory infection HAs, day of the week, and public holidays. We conducted a number of sensitivity analyses to assess model specification.We observed weak associations between total asthma HAs and O3 at lags of 1 day (RR10 ppb = 1.012, 95% CI: 1.004-1.021), 2 days (RR10 ppb = 1.011, 95% CI: 1.002-1.019), and 0-3 days (RR10 ppb = 1.017, 95% CI: 1.005-1.030). The associations were primarily observed in children aged 5-14 years (e.g., for O3 at lag 0-3 days, RR10 ppb = 1.037, 95% CI: 1.011-1.064), and null in individuals 15 years or older. The effect estimates did not change significantly with adjustment for pollen and respiratory infections, but they attenuated considerably and lost statistical significance when August and September data were excluded. A significant interaction between time around the start of the school year and O3 at lag 2 day was observed, with the associations with pediatric asthma HAs stronger in August and September (RR10 ppb = 1.040, 95% CI: 1.012-1.069) than in the rest of the year (October-July) (RR10 ppb = 1.006, 95% CI: 0.986-1.026).We observed small but statistically significant positive associations between total and pediatric asthma HAs and short-term O3 exposure in Texas, especially in August and September. Further research is needed to determine how the start of school could modify the observed association between O3 and pediatric asthma HAs.

Project description:BackgroundFactors associated with hospital mortality are unclear in patients with acute exacerbation of COPD (AECOPD) requiring intensive care unit (ICU) admission. We aimed to characterize these patients and identify factors associated with hospital mortality.Patients and methodsWe used a retrospective observational case-control design and recruited patients between January 2015 and March 2017. Of 146 patients enrolled, 24 (16.4%) died during their hospital stay, while 122 survived.ResultsMultivariate logistic regression analyses revealed factors associated with hospital mortality: age (adjusted odds ratio [AOR] 1.12, 95% CI: 1.03-1.23), C-reactive protein (CRP) level >7.5 mg/dL at the emergency room (AOR 4.52, 95% CI: 1.27-16.04), peak eosinophil-to-neutrophil ratio (ENR)×102 on days 8-14 of treatment (AOR 0.22, 95% CI: 0.08-0.63), and in-hospital complications (AOR 4.23, 95% CI: 1.12-15.98) (all P<0.05). After receiver operating characteristic curve analyses, cutoff level for peak ENR×102 was 0.224. To examine the synergistic effects of CRP level and peak ENR, we divided patients into four groups: (G0, reference group) Peak ENR×102 >0.224 on days 8-14 and initial CRP <7.5 mg/dL; (G1) Peak ENR×102 >0.224 on days 8-14 and initial CRP >7.5 mg/dL; (G2) Peak ENR×102 <0.224 on days 8-14 and initial CRP <7.5 mg/dL; and (G3) Peak ENR×102 <0.224 on days 8-14 and initial CRP >7.5 mg/dL. For G2 and G3 patients, the AOR of mortality was significantly different from that of the reference group (G2: AOR 10.00, P = 0.020; G3: AOR 61.79, P<0.001). The relationship between 28-day mortality and the four groups was statistically significant (log-rank test, P<0.001).ConclusionOlder age, initial CRP >7.5 mg/dL, peak ENR on days 8-14, and in-hospital complications were associated with hospital mortality in patients with AECOPD requiring ICU admission. Patients with both biomarkers, initial CRP >7.5 mg/dL, and peak ENR×102 <0.224 on days 8-14 of treatment, had an increased risk of hospital mortality.

Dataset Information

Relationship between exposure to ozone and exacerbation requiring hospital admission among patients with asthma: a case-control study in central Taiwan.

Objective

Setting

Participants

Primary and secondary outcome measures

Results

Conclusions

Publications

Relationship between exposure to ozone and exacerbation requiring hospital admission among patients with asthma: a case-control study in central Taiwan.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets