Randomised controlled trial: Continuous positive airway pressure as treatment for systemic hypertension in people with obstructive sleep apnoea
Clinical relevance remains uncertain
Obstructive sleep apnoea is a common respiratory condition, characterised by repetitive obstruction of the upper airways.1 It is a recognised risk factor for systemic hypertension.2 In patients with moderate to severe obstructive sleep apnoea , continuous positive airway pressure (CPAP) is the treatment of choice.3 CPAP works through a machine that emits a constant flow of air which keeps airways open as the patient sleeps. If CPAP can control obstructive sleep apnoea , and obstructive sleep apnoea is associated with systemic hypertension, then CPAP might improve untreated hypertension, which is what the authors wanted to investigate.
As well as being randomised, the trial was double blind, meaning that neither the patients nor the researchers knew who received actual or sham CPAP. Blinding also reduces the risk of bias. Furthermore, so the results could be applied to a wide range of patients, the authors performed a multicentre trial, studying 340 patients