UC San Diego

Background & aims

Heterogeneous presentations and disease mechanisms among patients with laryngeal symptoms account for misdiagnosis of laryngopharyngeal reflux (LPR), variations in testing, and suboptimal outcomes. We aimed to derive phenotypes of patients with laryngeal symptoms based on clinical and physiologic data and to compare characteristics across phenotypes.

Methods

A total of 302 adult patients with chronic laryngeal symptoms were prospectively enrolled at 3 centers between January 2018 to October 2020 (age 57.2 ± 15.2 years; 30% male; body mass index 27.2 ± 6.0 kg/m²). Discriminant analysis of principal components (DAPC) was applied to 12 clinical and 11 physiologic variables collected in stable condition to derive phenotypic groups.

Results

DAPC identified 5 groups, with significant differences across symptoms, hiatal hernia size, and number of reflux events (P < .01). Group A had the greatest hiatal hernia size (3.1 ± 1.0 cm; P < .001) and reflux events (37.5 ± 51; P < .001), with frequent cough, laryngeal symptoms, heartburn, and regurgitation. Group B had the highest body mass index (28.2 ± 4.6 kg/m²; P < .001) and salivary pepsin (150 ± 157 ng/mL; P = .03), with frequent cough, laryngeal symptoms, globus, heartburn, and regurgitation. Group C frequently reported laryngeal symptoms (93%; P < .001), and had fewest esophageal symptoms (9.6%; P < .001) and reflux events (10.7 ± 11.0; P < .001). Group D commonly reported cough (88%; P < .001) and heartburn. Group E (18%) was oldest (62.9 ± 14.3 years; P < .001) and distinguished by highest integrated relaxation pressure.

Conclusions

DAPC identified distinct clinicophysiologic phenotypes of patients with laryngeal symptoms referred for reflux evaluation: group A, LPR and gastroesophageal reflux disease (GERD) with hiatal hernia; group B, mild LPR/GERD; group C, no LPR/No GERD; group D, reflex cough; and group E, mixed/possible obstructive esophagogastric junction. Phenotypic differences may inform targeted clinical trials design and improve outcomes.