RT Journal Article SR Electronic T1 Sleep ยท 2: Pathophysiology of obstructive sleep apnoea/hypopnoea syndrome JF Thorax JO Thorax FD BMJ Publishing Group Ltd and British Thoracic Society SP 159 OP 163 DO 10.1136/thorax.2003.015859 VO 59 IS 2 A1 R B Fogel A1 A Malhotra A1 D P White YR 2004 UL http://thorax.bmj.com/content/59/2/159.abstract AB The pathogenesis of airway obstruction in patients with obstructive sleep apnoea/hypopnoea syndrome is reviewed. The primary defect is probably an anatomically small or collapsible pharyngeal airway, in combination with a sleep induced fall in upper airway muscle activity.