Are chronic cough and laryngopharyngeal reflux more common in obstructive sleep apnea patients?

Objectives/hypothesis: To assess if there is a significant difference in the prevalence and severity of chronic cough symptoms in obstructive sleep apnea (OSA) patients versus non-OSA patients and examine this relationship in regard to laryngopharyngeal reflux (LPR) symptoms.

Study design: Prospective cohort study.

Methods: Patients referred to Northwestern Medicine Sleep Lab for home sleep testing were enrolled. Patients filled out the Leicester Cough Questionnaire (LCQ) and Reflux Symptom Index (RSI) before completing sleep testing. Home sleep testing results were reviewed, and patients were separated into non-OSA and OSA groups by standard Apnea-Hypopnea Index (AHI) criteria. Demographic characteristics and questionnaire scores of the two groups were compared. The relationship between OSA severity, as determined by AHI, and LCQ and RSI scores was assessed.

Results: Of the 52 patients enrolled, 33 patients met criteria for OSA and 19 patients did not. Comparing patients without OSA versus those with OSA, there was a significant difference in mean LCQ score (129.9 vs. 120.0, respectively; P = .02), implying worse cough symptoms among OSA patients, and mean RSI score (3.2 vs. 11.2, respectively; P = .0013), implying worse upper-airway reflux symptoms among OSA patients. There was a significant correlation between LCQ score and AHI (r = -0.39, P = .0061) and between RSI score and AHI (r = 0.37, P = .0078).

Conclusions: OSA patients demonstrate worse chronic cough and LPR-related quality of life versus non-OSA patients. Furthermore, the severity of these quality-of-life measures was correlated with the severity of the AHI. Chronic cough and particularly the pharyngeal LPR symptoms may be associated with the presence and severity of OSA.

Level of evidence: 2 . Laryngoscope, 129:1244-1249, 2019.