Clinical characteristics and impact of inducible laryngeal obstruction in the UK national registry.

Abstract

Background: Inducible laryngeal obstruction (ILO) describes inappropriate laryngeal closure during respiration, with airflow obstruction occurring at the glottic and/or supraglottic level, leading to breathlessness.

Objective: There is a paucity of data describing the demographics and impact of ILO. We aimed to report the clinical and demographic features of ILO in individuals entered prospectively in the UK national ILO registry.

Methods: Data were entered into a web-based registry from participants with endoscopically confirmed ILO, attending four established UK-wide specialist ILO centres between March 2017-November 2019. All patients provided written informed consent.

Results: Data from 137 individuals were included; the majority (87%) had inspiratory ILO and required provocation during endoscopy to induce symptoms. There was a female predominance (80%) and a mean (SD) age 47(15) years. The most common comorbidities included asthma (68%) and reflux (57%). Health care utilisation was high: 88% had attended emergency healthcare with symptoms at least once in the previous 12 months and nearly half had been admitted to hospital. A fifth had required admission to critical care due to ILO symptoms. Patient morbidity was substantial with 64% reporting impaired functional capacity (≥3 MRC Dyspnoea Scale) and a third stated that symptoms impacted working capability.

Conclusion: We describe the first multicentre prospective characterisation of individuals with endoscopically diagnosed ILO. Analysis of our multicentre data set identified ILO as associated with a high burden of morbidity and health care utilisation, comparable to severe asthma. These data will support development of healthcare resources in the future and guide research priorities.

Keywords: Asthma; cough; dyspnoea; inducible laryngeal obstruction; larynx; vocal cord dysfunction.