Laryngeal hypersensitivity and abnormal cough response during mannitol bronchoprovocation challenge

Area of Science:

• Respiratory Medicine
• Clinical Physiology

Background:

• Inhalational mannitol challenge may trigger cough via bronchoconstriction or laryngeal irritation.
• This study aimed to differentiate the laryngeal and bronchial contributions to mannitol-induced cough.

Purpose of the Study:

• To investigate the relationship between cough, laryngeal hypersensitivity, and bronchial hyperresponsiveness (BHR) during mannitol challenge.
• To identify patient clusters based on cough characteristics.

Main Methods:

• Prospective observational study of patients undergoing mannitol challenge.
• Audio-recorded coughs, Newcastle Laryngeal Hypersensitivity Questionnaire (LHQ), and BHR assessment.
• K-means cluster analysis to classify cough patterns.

Main Results:

• Cough frequency correlated with laryngeal hypersensitivity (p=0.004), not BHR.
• Abnormal laryngeal hypersensitivity was associated with higher cough frequency (p=0.042).
• Cluster analysis revealed distinct groups based on age, sex, cough frequency, and laryngeal sensitivity.

Conclusions:

• Mannitol challenge-induced cough primarily reflects laryngeal hypersensitivity.
• Laryngeal hypersensitivity is more prevalent in older females.
• Mannitol challenge can be a valuable tool for assessing both laryngeal hypersensitivity and BHR.