Airway resistance and reactance are affected in systemic sclerosis
Related Experiment Video
Updated: Mar 28, 2026
Employing the Forced Oscillation Technique for the Assessment of Respiratory Mechanics in Adults
Published on: February 9, 2022
David Aronsson1, Roger Hesselstrand2, Gracijela Bozovic3
1Respiratory Medicine and Allergology, Department of Clinical Sciences Lund, Skåne University Hospital, Lund University, Lund, Sweden.
Background:
Interstitial lung disease often occurs as an early complication of systemic sclerosis (SSc). The aim was to investigate whether impulse oscillometry (IOS) could be used to evaluate lung impairment in SSc.
Methods:
Seventy-eight SSc patients, of which 65 had limited cutaneous SSc (lcSSc) and 13 had diffuse cutaneous SSc (dcSSc), were subjected to high-resolution computed tomography (HRCT) and pulmonary function tests (spirometry, IOS, and single breath CO diffusion capacity test). Twenty-six healthy individuals served as controls.
Results:
Patients with lcSSc had higher levels of peripheral airway resistance, that is, R5-R20 (difference between resistance at 5 Hz and resistance at 20 Hz) showed a median (and interquartile range) of 0.05 (0.02-0.09) in lcSSc, 0.01 (0.00-0.04) in dcSSc and 0.04 (0.01-0.06) in healthy controls. They also had higher levels of reactance: reactance area was 0.26 (0.15-0.56) in lcSSc, 0.20 (0.11-0.29) in dcSSc and 0.18 (0.08-0.30) in healthy controls, and resonant frequency was 10.9 (8.8-14.8) in lcSSc, 9.0 (8.3-11.6) in dcSSc and 9.1 (8.0-13.1) in healthy controls. Airway reactance correlated to fibrotic findings on HRCT, such as ground glass opacities and reticulations.
Discussion:
This implies that IOS parameters to some extent are related to fibrosis in patients with SSc.
Related Concept Videos
01:19Factors Affecting Pulmonary Ventilation
Alveolar Surface Tension
The alveolar fluid lines the luminal surface of the alveoli and exerts a force called surface tension. This force is caused by the polar water molecules in the liquid being more strongly attracted to each...
01:20Chronic Obstructive Pulmonary Disease-II: Pathophysiology
Chronic Inflammation
01:26Asthma-II: Pathophysiology and Classification
Additionally, environmental and genetic factors play crucial roles in determining an individual's susceptibility to asthma and the severity of their condition.
Critical processes in asthma pathophysiology include:
01:20Vascular Resistance
The primary determinants of vascular resistance are vessel diameter, blood viscosity, and vessel length. Among these, vessel diameter plays the most significant role due to the fourth power relationship described by...
01:24Pressure Relationships in Thoracic Cavity
Breathing Mechanisms
Both intra-alveolar and intrapleural pressures rely on specific lung properties. The ability to breathe—allowing air to enter the lungs...
01:20Asthma: Pathogenesis and Management
Asthma is classified as allergic and non-allergic. Allergens such as dust mites, pollen, and pet dander trigger allergic asthma, while factors like cold air, intense emotions, or exercise can induce non-allergic asthma.