Impulse oscillometry defined small airway dysfunction in asthmatic patients with normal spirometry: Prevalence, clinical associations, and impact on asthma control.

Background: The small-airway dysfunction (SAD), detected with impulse oscillometry (IOS) methods, has been recently better characterized in patients with asthma. However, little is known about SAD in asthmatic patients with normal spirometry (NS).

Objective: In this study, we aimed to investigate, in an unselected sample of 321 patients with physician-diagnosed asthma and NS, prevalence, clinical characterization, and impact on asthma control of IOS-defined SAD.

Small airway dysfunction and poor asthma control: a dangerous liaison.

Asthma is a common chronic condition, affecting approximately 339 million people worldwide. The main goal of the current asthma treatment guidelines is to achieve clinical control, encompassing both the patient symptoms and limitations and the future risk of adverse asthma outcomes. Despite randomized controlled trials showing that asthma control is an achievable target, a substantial proportion of asthmatics remain poorly controlled in real life.

Prevalence and features of IOS-defined small airway disease across asthma severities.

Background: Impulse oscillometry (IOS) is a noninvasive method based on the forced oscillation technique able to detect small airway dysfunction (SAD) in asthma. We aimed to analyze the prevalence and the functional features of IOS-defined SAD across the different Global Initiative for Asthma (GINA) steps.

Methods: A cross-sectional, single-center study in which 400 consecutive adult patients with physician-diagnosed, community-managed asthma underwent standard spirometry and IOS, and were stratified by stepwise GINA classification.

Clinical Characterization and Predictors of IOS-Defined Small-Airway Dysfunction in Asthma.

Background: The involvement of small airways has recently gained greater recognition in asthma. Impulse oscillometry (IOS) is a simple and noninvasive method based on the forced oscillation technique, for the detection of small-airway dysfunction (SAD).

Objective: To identify the predictors of SAD in an unselected sample of 400 patients with physician-diagnosed asthma.