The bidirectional relationship between sleep apnea and hypertension: A comprehensive narrative review of pathophysiology, clinical evidence, and therapeutic implications
Pushpita Das Srishty, Sourov Dey, Shade Mohammed Jubair, Ferdous Al-Mahbub, Nice Chowddhury, Orpita Das Sreya, Piyasha Mazumder, Md Nazmul KabirAbstract
Background:
Sleep apnea (SA), predominantly in its obstructive form (OSA), and hypertension (HTN) are 2 of the most prevalent chronic conditions worldwide, each independently associated with substantial cardiovascular morbidity and mortality. Mounting evidence supports a bidirectional, self-reinforcing pathophysiological relationship between these 2 disorders, yet this interplay remains underappreciated in routine clinical practice.
Methods:
We conducted a comprehensive narrative review of peer-reviewed literature published between 1990 and 2025. Databases searched included PubMed/MEDLINE, EMBASE, and the Cochrane Library using search terms encompassing obstructive sleep apnea, central sleep apnea, HTN, resistant HTN, blood pressure, sympathetic nervous system, intermittent hypoxia, continuous positive airway pressure, and related mechanistic and therapeutic terms. Landmark prospective cohort studies, randomized controlled trials, systematic reviews, meta-analyses, and high-quality mechanistic studies were included.
Results:
Obstructive SA affects 9–38% of the adult population and is independently associated with a 2.89-fold increased risk of incident HTN in prospective cohorts. Mechanistic pathways driving OSA-associated HTN include intermittent hypoxia-mediated sympathoexcitation, oxidative stress, endothelial dysfunction, renin–angiotensin–aldosterone system upregulation, systemic inflammation, and impaired baroreflex sensitivity. Conversely, HTN perpetuates OSA through nocturnal rostral fluid redistribution causing upper airway edema, aldosterone-mediated pharyngeal narrowing, and altered ventilatory control. Resistant HTN (RH) exhibits OSA prevalence rates of 64–83%. Continuous positive airway pressure therapy produces mean systolic blood pressure reductions of 2–3 mmHg, with substantially greater effects in RH, severe OSA, and patients with high nocturnal hypoxemic burden. Mineralocorticoid receptor antagonists show dual benefit in the RH–OSA–-aldosterone excess phenotype.
Conclusions:
Obstructive SA and HTN form a bidirectional, self-amplifying pathological cycle. Systematic OSA screening in hypertensive patients and blood pressure evaluation in patients with OSA are warranted. Integrated, multidisciplinary management targeting both conditions simultaneously offers the greatest potential for cardiovascular risk reduction.