Evening and morning exhaled volatile compound patterns are different in obstructive sleep apnoea assessed with electronic nose

Purpose Electronic noses represent a technique for the measurement of exhaled breath volatile compound pattern which can discriminate patients with obstructive sleep apnoea (OSA) from control subjects. Although overnight changes in circulating biomarkers were reported, this effect on the exhaled volatile compound pattern has not been studied before. We aimed to compare breath patterns in the evening and in the morning in patients with OSA and to study the ability of the electronic nose to distinguish patients from controls based on these exhaled volatile patterns.