Resistant hypertension, obstructive sleep apnoea and aldosterone

Area of Science:

• Sleep Medicine
• Cardiology
• Endocrinology

Background:

• Obstructive sleep apnea (OSA) and hypertension frequently coexist, with observational studies linking untreated OSA to increased hypertension risk.
• Prospective studies suggest OSA may elevate incident hypertension risk in normotensive individuals.
• Continuous positive airway pressure (CPAP) therapy shows a modest overall effect on blood pressure (BP).

Purpose of the Study:

• To explore the discrepancy between the strong association of OSA with hypertension and the limited BP benefits of CPAP therapy.
• To investigate the high prevalence of OSA in patients with resistant hypertension (RHTN).
• To examine the role of aldosterone in the relationship between OSA and hypertension.

Main Methods:

• Review of observational and prospective studies on OSA and hypertension.
• Analysis of randomized controlled trials evaluating CPAP for BP reduction.
• Examination of studies investigating hyperaldosteronism in patients with RHTN and OSA.

Main Results:

• While CPAP has a modest overall BP effect, individual responses vary significantly, with some patients experiencing substantial antihypertensive benefits.
• OSA is highly prevalent in RHTN patients, with aldosterone levels correlating to OSA severity.
• Aldosterone blockade has been shown to reduce OSA severity in RHTN patients.

Conclusions:

• Aldosterone excess may contribute to worsening OSA, potentially by increasing fluid accumulation in the neck and exacerbating upper airway resistance.
• Further research is needed to understand the mechanisms linking OSA, hypertension, and aldosterone.
• Targeting aldosterone could be a potential therapeutic strategy for managing OSA in specific patient populations.