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Annals of Allergy, Asthma & Immunology... Sep 2023In the year 2035, projections have estimated that 5% of the Scottish population will be morbidly obese defined as a body mass index (BMI) greater than or equal to 40...
BACKGROUND
In the year 2035, projections have estimated that 5% of the Scottish population will be morbidly obese defined as a body mass index (BMI) greater than or equal to 40 kg/m. Airway oscillometry is an effort-independent test akin to bronchial sonar which measures resistance and compliance.
OBJECTIVE
To evaluate the impact of obesity on lung mechanics using oscillometry.
METHODS
Clinical data for 188 patients with respiratory physician-diagnosed moderate-to-severe asthma were retrospectively collected and analyzed.
RESULTS
Obesity (BMI 30-39.9 kg/m) and morbid obesity (BMI ≥ 40 kg/m) were associated with a significantly worse heterogeneity of peripheral resistance between 5 Hz and 20 Hz and peripheral compliance as low-frequency reactance at 5 Hz and area under the reactance curve, as compared with normal weight (BMI 18.5-24.9 kg/m). Cluster analysis incorporating oscillometry identified a patient cohort who was older, obese, and female with combined impairment of spirometry and oscillometry coupled with more frequent severe exacerbations.
CONCLUSION
Obesity is associated with worse peripheral airway dysfunction in moderate-to-severe asthma, including a patient cluster who was older, obese, and female with more frequent exacerbations.
Topics: Humans; Adult; Female; Obesity, Morbid; Retrospective Studies; Oscillometry; Asthma; Lung; Spirometry
PubMed: 37209835
DOI: 10.1016/j.anai.2023.05.014 -
Environmental Pollution (Barking, Essex... Aug 2023Exposure to phthalates and synthetic phenols is ubiquitous. Some of them are suspected to impact child respiratory health, although evidence still remains insufficient....
Exposure to phthalates and synthetic phenols is ubiquitous. Some of them are suspected to impact child respiratory health, although evidence still remains insufficient. This study investigated the associations between prenatal exposure to phthalates and phenols, individually and as a mixture, and child respiratory health assessed by objective lung function measures since 2 months of age. Among 479 mother-child pairs from the SEPAGES cohort, 12 phenols, 13 phthalate and 2 non-phthalate plasticizer metabolites were measured in 2 pools including each 21 urine samples collected at the 2nd and 3rd pregnancy trimesters. Lung function was measured at 2 months using tidal breathing flow-volume loops and nitrogen multiple-breath washout, and at 3 years using oscillometry. Asthma, wheezing, bronchitis and bronchiolitis were assessed by repeated questionnaires. A cluster-based analysis was applied to identify exposure patterns to phenols and phthalates. Adjusted associations between clusters as well as each individual exposure biomarker and child respiratory health were estimated by regression models. We identified four prenatal exposure patterns: 1) low concentrations of all biomarkers (reference, n = 106), 2) low phenols-moderate phthalates (n = 162), 3) high concentrations of all biomarkers except bisphenol S (n = 109), 4) high parabens-moderate other phenols-low phthalates (n = 102). At 2 months, cluster 2 infants had lower functional residual capacity and tidal volume and higher ratio of time to peak tidal expiratory flow to expiratory time (t/t) and cluster 3 had lower lung clearance index and higher t/t. Clusters were not associated with respiratory health at 3 years but in the single-pollutant models, parabens were associated with increased area of the reactance curve, bronchitis (methyl, ethyl parabens) and bronchiolitis (propyl paraben). Our results suggested that prenatal exposure to mixtures of phthalates reduced lung volume in early life. Single exposure analyses suggested associations of parabens with impaired lung function and increased risk of respiratory diseases.
Topics: Pregnancy; Female; Infant; Humans; Parabens; Environmental Exposure; Prenatal Exposure Delayed Effects; Environmental Pollutants; Phenols; Phthalic Acids; Bronchitis; Biomarkers
PubMed: 37178953
DOI: 10.1016/j.envpol.2023.121794 -
Journal of Investigational Allergology... Apr 2024Background: Static lung hyperinflation (SLH) measured using body plethysmography in patients with asthma is associated with poor outcomes. The severity of SLH may be... (Observational Study)
Observational Study
BACKGROUND AND OBJECTIVES
Background: Static lung hyperinflation (SLH) measured using body plethysmography in patients with asthma is associated with poor outcomes. The severity of SLH may be associated with small airway dysfunction (SAD), which can be measured using impulse oscillometry (IOS). Objective: This study aims to determine the correlation between SLH and SAD in patients with severe asthma and assess the improvement in SLH and SAD with treatment.
METHODS
We analyzed data from patients who were enrolled in the Taiwan Severe Asthma Registry, which comprises a prospective observational cohort. Plethysmography and IOS were performed regularly. The relationship between spirometry and IOS parameters was determined. Changes in the clinical outcomes in response to treatment were analyzed.
RESULTS
Of 107 patients with severe asthma, 83 (77.6%) had SLH based on an increased residual volume to total lung capacity ratio (RV/ TLC). Most patients were older women with worse pulmonary function and SAD than those without SLH. SAD, defined as increased airway resistance/reactance, was significantly correlated with SLH. Airway reactance at 5 Hz (X5) ≤-0.21 kPa/(L/s) detected SLH with an area under the receiver operating characteristic curve of 0.84 (P<.0001; sensitivity, 85.2%; and specificity, 83.3%). After 12 months, patients who received add-on biologics (vs those who did not) had significantly reduced exacerbations, fractional exhaled nitric oxide level, and blood eosinophil counts, as well as improved forced expiratory volume in the first second, X5, and a trend toward reduced RV/TLC ratio.
CONCLUSIONS
In severe asthma, airway reactance (X5) could be a novel parameter for assessing SLH.
Topics: Aged; Female; Humans; Asthma; Forced Expiratory Volume; Lung; Respiratory Function Tests; Spirometry; Prospective Studies
PubMed: 36645713
DOI: 10.18176/jiaci.0888