(0835) Symptoms of Laryngeal Hypersensitivity in Patients With Idiopathic Subglottic Stenosis

Introduction: Chronic nonspecific cough, throat clearing, paradoxical vocal fold motion, inducible laryngeal obstruction, and laryngospasm are possibly secondary to hypersensitivity of the larynx. Patients with these symptoms often score positively on the Newcastle Laryngeal Hypersensitivity Questionnaire (NLHQ), a validated patient-reported outcome measure designed to assess sensations indicative of neurogenic laryngeal hypersensitivity (NLH). The primary objective of this study was to evaluate the comorbidity of idiopathic subglottic stenosis (iSGS) with NLH as represented by NLHQ scores.

Methods: A prospective online survey to an airway stenosis support group gathered NLHQ scores in patients diagnosed with iSGS. The survey assessed patient-reported disease status and effort of breathing at time of survey completion.

Results: 709 of 888 patients with iSGS (79.8%) had a clinically positive score of < 17.1 on the NLHQ. The correlation coefficient between NLHQ score as a continuum and self-reported visual analog scale (VAS) ratings of breathing effort was 0.33 (p-value < 0.001). The VAS ratings of breathing effort were correlated against 3 subdomains of the NLHQ (obstruction, pain/thermal, and throat tickle), with correlation coefficients of 0.35, 0.24, and 0.27, respectively (p-values < 0.001). VAS breathing effort scores were correlated against each NLHQ question. Overall, the most frequently experienced symptom was a feeling of phlegm or mucus in the throat, however, this was only weakly correlated with effort of breathing.

Conclusions: 80% of patients with iSGS report symptoms that could be consistent with NLH as evidenced by positive NLHQ scores. However, disease severity, as indicated by patient-reported high effort of breathing, was only weakly correlated to scores on NLHQ. Therefore, patients may clinically benefit from respiratory retraining therapy. Future studies will examine the relationship between objective measures of airway size and pulmonary function tests with NLHQ scores to determine if the NLHQ is predictive of iSGS disease severity.