Project Details
Description
Background
There is a wide interest in understanding the contribution of small airways to the clinical expression and the severity of obstructive lung diseases, i.e. COPD and asthma. Forced oscillometry technique (FOT) measures the mechanical properties of the respiratory system and can be used to assess small airway dysfunction, which is not plausible for spirometry. Ventilation/Perfusion-SPECT is an imaging technique that map both ventilation and perfusion of the lungs and has shown a sensitivity in evaluating impaired ventilation at an early stage.
Aims
The project focuses on less-explored methods to evaluate the degree of airflow limitation in patients with COPD and asthma. Hypotheses: A) Expiratory versus inspiratory resistance and reactance can be used to evaluate expiratory airflow limitation and its correlation to air trapping, symptoms and quality of life. B) Airway hyperresponsiveness to mannitol is associated with small airways and inspiratory versus expiratory resistance and reactance. C) Expiratory airflow limitation is evident in patients with a defined airway obstruction, both in subjects with or without COPD. D) Peripheral airway obstruction in younger and older smokers with or without signs of COPD are associated with deficient functionality defined by imaging.
Work plan
Patients with a mild grade of obstructive diseases, COPD and asthma, healthy smokers and healthy subjects were included in project 1-2. Subjects in project 3 and 4 were COPD patients, healthy smokers, and healthy non-smokers. In addition to spirometry, we used two main techniques in this project, FOT and V/P SPECT, to investigate airway obstruction. The patients also answered to questionnaires about airway symptoms and quality of life.
A) COPD-patients had an increased expiratory airflow limitation in FOT-variables that assess the peripheral airways compared to asthmatic patients and healthy subjects, but similar to healthy smokers. B) There was an association between the response of bronchial hyperreactivity to mannitol and impaired FOT-measurements, as well as impaired baseline FOT-values. C and D) ongoing
Significance
In the first projects, there is evidence for impaired expiratory flow limitation of the peripheral airways in both COPD and asthma, and an association to both air trapping and symptoms. In addition, subjects with increased bronchial hyperresponsiveness to mannitol also show an increased airway resistance and reactance at baseline.
There is a wide interest in understanding the contribution of small airways to the clinical expression and the severity of obstructive lung diseases, i.e. COPD and asthma. Forced oscillometry technique (FOT) measures the mechanical properties of the respiratory system and can be used to assess small airway dysfunction, which is not plausible for spirometry. Ventilation/Perfusion-SPECT is an imaging technique that map both ventilation and perfusion of the lungs and has shown a sensitivity in evaluating impaired ventilation at an early stage.
Aims
The project focuses on less-explored methods to evaluate the degree of airflow limitation in patients with COPD and asthma. Hypotheses: A) Expiratory versus inspiratory resistance and reactance can be used to evaluate expiratory airflow limitation and its correlation to air trapping, symptoms and quality of life. B) Airway hyperresponsiveness to mannitol is associated with small airways and inspiratory versus expiratory resistance and reactance. C) Expiratory airflow limitation is evident in patients with a defined airway obstruction, both in subjects with or without COPD. D) Peripheral airway obstruction in younger and older smokers with or without signs of COPD are associated with deficient functionality defined by imaging.
Work plan
Patients with a mild grade of obstructive diseases, COPD and asthma, healthy smokers and healthy subjects were included in project 1-2. Subjects in project 3 and 4 were COPD patients, healthy smokers, and healthy non-smokers. In addition to spirometry, we used two main techniques in this project, FOT and V/P SPECT, to investigate airway obstruction. The patients also answered to questionnaires about airway symptoms and quality of life.
A) COPD-patients had an increased expiratory airflow limitation in FOT-variables that assess the peripheral airways compared to asthmatic patients and healthy subjects, but similar to healthy smokers. B) There was an association between the response of bronchial hyperreactivity to mannitol and impaired FOT-measurements, as well as impaired baseline FOT-values. C and D) ongoing
Significance
In the first projects, there is evidence for impaired expiratory flow limitation of the peripheral airways in both COPD and asthma, and an association to both air trapping and symptoms. In addition, subjects with increased bronchial hyperresponsiveness to mannitol also show an increased airway resistance and reactance at baseline.
| Status | Active |
|---|---|
| Effective start/end date | 2024/01/01 → 2025/12/31 |
Funding
- The Swedish Heart Lung Foundation
