TY - JOUR T1 - When CPAP is stopped: what are the “on switches” of sleep apnoea? JF - European Respiratory Journal JO - Eur Respir J SP - 1227 LP - 1229 DO - 10.1183/09031936.00003614 VL - 43 IS - 5 AU - Kingman P. Strohl AU - Andrew Wellman Y1 - 2014/05/01 UR - http://erj.ersjournals.com/content/43/5/1227.abstract N2 - Adult sleep apnoea is considered a relatively common and chronic disease, with the defining features of sleep disordered breathing (apnoeas, hypopneas and respiratory effort-related arousals) leading to its consequences. The physiological sequelae include a fall in oxygen and rise in carbon dioxide, changes in intrathoracic pressure and cardiac performance, and/or arousals from sleep [1]. Morbidity and mortality occur due to daytime inattention and sleepiness (leading to impaired quality of life with drowsiness, and fall-asleep crashes and accidents), metabolic syndrome [2] and cardiovascular disease (hypertension, stroke, arrhythmia, coronary artery disease, etc.) [3, 4], with some recent evidence that apnoeas might confer a greater risk of cancer or cancer progression [5, 6]. Yet it is widely accepted that there is imprecision in the links between events in sleep and these adverse outcomes, so that determining an individual’s prognosis and need for immediate therapy is an uncertain art.Obstructive sleep apnoea hypopnoea syndrome (OSAHS) is defined by symptoms of unrefreshing and disturbed sleep, loud snorts and snoring, and a certain number of events (usually more than five per hour) in a summary value called the apnoea–hypopnea index, and is relieved of symptoms when it is treated most directly by tracheostomy [7]. Continuous positive airway pressure (CPAP) has replaced tracheostomy as a therapy to reduce sleepiness and improve quality of life [8].In this issue of the European Respiratory Journal, Rossi et al. [9] report that about a third of CPAP-treated obstructive sleep apnoea (OSA) patients do not experience recurrence of oxygen desaturations after four nights and ∼10% do not experience recurrence following 2 weeks of intentional CPAP withdrawal. All had been treated for >2 years. As the authors freely admit, this is a paper … ER -