Peripheral airways dysfunction measured by oscillometry differentiates asthma from inducible laryngeal obstruction

Patrick Donohue; Margaret Connolly; Marcus D'Alfonso; Gerriann Jackson; Liane C Grasso; Xueya Cai; Ashley P O'Connell Ferster; G Todd Schneider; Sandhya Khurana; Steve N Georas

doi:10.1016/j.rmed.2024.107905

Peripheral airways dysfunction measured by oscillometry differentiates asthma from inducible laryngeal obstruction

Respir Med. 2024 Dec 3:236:107905. doi: 10.1016/j.rmed.2024.107905. Online ahead of print.

Authors

Affiliations

¹ Division of Pulmonary and Critical Care Medicine, University of Rochester School of Medicine and Dentistry, 601 Elmwood Ave, Rochester, NY, 14642, USA; Mary Parkes Center for Asthma, Allergy & Pulmonary Care, 400 Red Creek Drive, Suite 110, Rochester, NY, 14623, USA. Electronic address: Patrick_donohue@urmc.rochester.edu.
² Division of Pulmonary, Critical Care, and Sleep Medicine, University of Maryland Medical Center, 22 South Greene Street, Baltimore, MD, 21201, USA. Electronic address: maconnolly@som.umaryland.edu.
³ Division of Pulmonary and Critical Care Medicine, University of Rochester School of Medicine and Dentistry, 601 Elmwood Ave, Rochester, NY, 14642, USA. Electronic address: marcus_dalfonso@urmc.rochester.edu.
⁴ Department of Otolaryngology, University of Rochester School of Medicine and Dentistry, 601 Elmwood Ave, Rochester, NY, 14642, USA. Electronic address: gerriann_jackson@urmc.rochester.edu.
⁵ Department of Otolaryngology, University of Rochester School of Medicine and Dentistry, 601 Elmwood Ave, Rochester, NY, 14642, USA. Electronic address: Liane_Grasso@urmc.rochester.edu.
⁶ Department of Biostatistics and Computational Biology, 265 Crittenden Boulevard, CU 420630, Rochester, NY, 14642, USA. Electronic address: Xueya_Cai@urmc.rochester.edu.
⁷ Department of Otolaryngology-Head and Neck Surgery, Tufts Medical Center, 800 Washington Street, Boston, MA, 02111, USA. Electronic address: Ashley.oconnellferster@tuftsmedicalcenter.org.
⁸ Department of Otolaryngology, University of Rochester School of Medicine and Dentistry, 601 Elmwood Ave, Rochester, NY, 14642, USA. Electronic address: glenn_schneider@urmc.rochester.edu.
⁹ Division of Pulmonary and Critical Care Medicine, University of Rochester School of Medicine and Dentistry, 601 Elmwood Ave, Rochester, NY, 14642, USA; Mary Parkes Center for Asthma, Allergy & Pulmonary Care, 400 Red Creek Drive, Suite 110, Rochester, NY, 14623, USA. Electronic address: sandhya_khurana@urmc.rochester.edu.
¹⁰ Division of Pulmonary and Critical Care Medicine, University of Rochester School of Medicine and Dentistry, 601 Elmwood Ave, Rochester, NY, 14642, USA; Mary Parkes Center for Asthma, Allergy & Pulmonary Care, 400 Red Creek Drive, Suite 110, Rochester, NY, 14623, USA. Electronic address: steve_georas@urmc.rochester.edu.

PMID: 39631550
DOI: 10.1016/j.rmed.2024.107905

Abstract

Background: Inducible laryngeal obstruction (ILO, also called vocal cord dysfunction) can be difficult to distinguish clinically from asthma. Limited studies have explored the use of respiratory oscillometry to detect changes unique to ILO, but more study is needed to determine if routine oscillometry can differentiate these two clinical entities.

Objective: Determine if impedance variables measured on routine oscillometry over tidal breathing vary between individuals with asthma and ILO.

Methods: Subjects with asthma and ILO were recruited to participate in a single-center, observational study at the University of Rochester Medical Center. Oscillometry measurements were obtained over tidal breathing according to technical standards. Exploratory oscillometry variables were analyzed, as well as standard oscillometry variables including measures of peripheral airways dysfunction.

Results: 25 subjects (12 with asthma and 13 with ILO) were recruited and included in the analysis. Measures of peripheral airways dysfunction including frequency dependence of resistance (R5-R20), area under the reactance curve (AX), and reactance at 5 Hz (X5) were significantly more abnormal in asthma subjects compared to ILO subjects (p = 0.039, p = 0.008, and p = 0.0327 respectively). Resistance at 5 Hz (R5) was not statistically different between asthma and ILO (p = 0.301). Exploratory variables, including inspiratory impedance and the standard deviation of impedance, were not significantly different between asthma and ILO.

Conclusion: Measures of peripheral airways dysfunction by oscillometry were significantly different in subjects with asthma compared to ILO and more significant in subjects with poor asthma control. There were no exploratory oscillometry variables that were significantly different between ILO and asthma.

Keywords: Asthma; Inducible laryngeal obstruction; Oscillometry; Physiology; Vocal cord dysfunction.