Obstructive sleep apnoea and hypertension: Current understanding, diagnosis and management

Obstructive sleep apnoea (OSA) is a common, underdiagnosed disorder characterised by upper airway collapse, intermittent hypoxia and sympathetic activation. Hypertension frequently coexists with OSA, with evidence supporting OSA-driven hypertension mediated by sympathetic overactivity, RAAS (renin-angiotensin-aldosterone system) activation and endothelial dysfunction. OSA-related hypertension often manifests as nocturnal hypertension and is linked to adverse cardiovascular outcomes. Prevalence is high in resistant hypertension, supporting targeted screening. Diagnosis should be considered in patients with daytime somnolence or refractory hypertension, using validated screening tools and sleep studies. Continuous positive airway pressure (CPAP) is the cornerstone of OSA management and can modestly lower blood pressure with cardiovascular benefit. Pharmacological management should follow hypertension guidelines, favouring agents that target relevant mechanisms (eg RAAS blockade and beta-blockade). Aldosterone antagonists are recommended in resistant hypertension. Emerging therapies, including endothelin receptor antagonists and GLP-1 receptor agonists, show promise but require further trials. This article reviews the epidemiology, mechanisms, diagnosis and management of OSA-related hypertension.