Prevalence and associated factors of obstructive sleep apnea in refractory hypertension

Abstract

Background:Refractory hypertension (RfHT) and obstructive sleep apnea (OSA) share common pathophysiological mechanisms and probably are intrinsically associated, but their prevalence, clinical profile, and polysomnography (PSG) pattern remain misunderstood.Objective:To describe OSA prevalence and PSG pattern of patients with RfHT in a large cohort of resistant hypertension (RHT).Methods:This is a cross-sectional study involving 418 RHT patients (30.9% male; mean age of 62.5 ± 9.9 years) who were submitted to full-night PSG. RfHT was defined as uncontrolled ambulatory blood pressure monitoring using five or more antihypertensive drugs, including spironolactone. Bivariate analysis compared RHT and RfHT and multivariate analysis was performed to assess the independent correlates of OSA.Results:A total of 90 patients (21.5%) were diagnosed with RfHT (26.7% male; mean age of 58.5 ± 8.3 years). In comparison with resistant ones, RfHT patients were younger, with higher smoking and previous cardiovascular diseases prevalence, especially stroke. There was no difference regarding anthropometric measures. OSA prevalence (80.0 vs. 82.9%) and moderate/severe OSA (51.1 vs. 57.0%) were similar in both groups as well as apnea–hypopnea index. In its turn, refractory hypertensive patients presented better sleep efficiency (78 vs. 71%), with higher total sleep time (315 vs. 281 min) and lower sleep latency (11 vs. 17 min). There was no difference regarding rapid eye movement sleep, oxygen saturation, microarousals index, and periodic limb movement.Conclusion:In this large RHT cohort, resistant and refractory hypertensive patients have similar OSA prevalence, although refractory ones, which by definition use spironolactone, are younger and apparently have a better sleep pattern.

2023 ESH Guidelines for the management of arterial hypertension The Task Force for the management of arterial hypertension of the European Society of Hypertension

“…The prevalence of secondary hypertension, especially primary aldosteronism [728] and atherosclerotic renal artery stenosis (particularly in older patients or patients with CKD) can be as high as 10-20% of patients with resistant hypertension [716]. Search for OSA (by sleep history and specific tests) should not be omitted because of the frequent involvement of this condition in resistant hypertension, including night-time hypertension [729][730][731][732][733].…”

A risk prediction nomogram for resistant hypertension in patients with obstructive sleep apnea

“…Ahmed et al 22 found that smoking and obesity were associated with increased risk for resistant hypertension in OSA patients. Smoking plays an important role in increasing blood pressure via activating sympathetic nerve system and interfering with the effects induced by certain antihypertensive drugs 27 . Neck circumference is commonly used to measure the degree of obesity in individuals, which has been demonstrated as independent risk factor for OSA with hypertension 28 .…”

Chronic intermittent hypoxia‐induced cardiovascular and renal dysfunction: from adaptation to maladaptation

“…The association between OSA and drug refractory HTN is well established. There is a high prevalence (∼80%) of sleep apnoea patients with drug‐resistant or refractory HTN, and OSA has been considered a secondary cause of drug‐resistant HTN (Chedier et al., 2022; Logan et al., 2001; Pedrosa et al., 2011).…”