Sleep fragmentation during rapid eye movement sleep and hypertension in obstructive sleep apnea

Abstract

Objective:Sleep fragmentation determined by repetitive arousals from sleep in obstructive sleep apnea (OSA) is associated with hypertension. We aimed to quantify the independent association of arousals during rapid eye movement (REM)/non-rapid eye movement (NREM) sleep with prevalent hypertension.Methods:We included adults with 4 h of total sleep time and at least 30 min of REM sleep obtained from overnight in-laboratory polysomnography. Logistic regression models were fitted to explore the association between arousals during REM/NREM sleep and prevalent hypertension. All models controlled for OSA metrics and arousals during NREM/REM sleep, either by statistical adjustment or by stratification.Results:The sample comprised of 11 643 patients, of which 10 055 were OSA patients. Fully adjusted models demonstrated significant dose-relationships between arousal index during REM sleep (AI-REM) and prevalent hypertension (P trend = 0.002). The higher relative odds of prevalent hypertension were most evident with AI-REM > 40 events/h. In OSA patients with arousal index during NREM sleep (AI-NREM) <15 events/h, every10-unit increase in the AI-REM was associated with 18% higher odds of hypertension (odds ratio, 1.18; 95% confidence interval, 1.11–1.27) in OSA. On the contrary, AI-NREM was not a significant predictor of hypertension in any of the models.Conclusions:Our findings indicate that arousals during REM sleep are associated with prevalent hypertension. This is clinically relevant because treatment of OSA is often limited to the first half of the sleep period leaving most of sleep fragmentation during REM sleep untreated.

Objective sleep characteristics and hypertension: a community-based cohort study

“…However, in Model 3 (after adjusting for all potential confounding factors), this association was no longer significant, suggesting that the relationship between arousal index and hypertension may be influenced by other factors. For instance, previous research has shown that the degree of hypoxia acts as a confounding factor in the association between arousal index and the development of hypertension ( 30 ). These findings are consistent with other studies, indicating that an increased arousal index suggests an increase in sleep fragmentation, which may raise the risk of hypertension ( 31 , 32 ).…”

REM sleep obstructive sleep apnoea

“…REM AHI was not associated with evening hypertensive BP levels. In a recent study in a cohort with >10 000 OSA patients, fully adjusted models demonstrated a significant dose–response relationship between arousal index during REM sleep (REM AI) and prevalent hypertension [ 89 ]. The highest odds ratio of prevalent hypertension was found in a subgroup with an REM AI >40 events·h −1 .…”

Approach the Patient With Obstructive Sleep Apnea and Obesity

“…The overall AHI may not be significantly elevated because REM sleep accounts for only approximately 20% of total sleep time. Severe REM OSA (AHI ≥ 30 during REM sleep) has an independent association with hypertension ( 142 , 143 ), and may be a more important predictor of hypertension then AHI during nREM sleep ( 144 ). Mood disturbance is more severe with REM OSA than nREM OSA ( 145 ).…”