Obstructive sleep apnoea (OSA) is being increasingly recognised as a cause of chronic cough. The impact of continuous positive airway pressure (CPAP) therapy and the mechanism of this association are not well understood. We describe a patient with OSA and chronic cough who responded well to CPAP. Objective and subjective assessments of cough on treatment with CPAP, off CPAP and on follow-up as well as pharyngeal pH monitoring suggest a possible mechanism for this association.
A 61-yr-old male who was a nonsmoker presented to the Hull Cough Clinic (Hull, UK) with a dry cough of 2 yrs’ duration. He did not complain of associated breathlessness or wheezing or a history of post-nasal drip. He did complain of heart burn and treatment with acid-suppressive therapy in the past lead to some improvement in his cough, though it continued to be a significant problem. Previous trials of inhaled and nasal corticosteroids did not improve his cough. He did not have any comorbidities and was not on regular medications. His body mass index was 31 kg·m−2. General physical examination and examination of the respiratory system were unremarkable. A chest radiograph and spirometry were normal. On further questioning, he had a history of snoring for many years. He also complained that his sleep quality was not good and he felt somewhat sleepy in the day time. His Epworth Sleepiness Scale score was 12. This raised the clinical suspicion of OSA. Treatment with lansoprazole was initiated and a sleep study was organised.
At review, on treatment with lansoprazole, his cough was slightly better, although, …
