Rayward Lionel, Ho Selina W K, Green Daniel, Little J Paige
Centre for Biomechanics and Sleep Research, Queensland University of Technology, Brisbane, Australia.
Sealy of Australia, Wacol, Australia.
J Sleep Res. 2025 Feb;34(1):e14325. doi: 10.1111/jsr.14325. Epub 2024 Aug 27.
Little is known about the physiological and biomechanical factors that determine individual preferences in lying posture during sleep. This study investigated relationships between position preference and position-specific arousals, awakenings, limb movements and limb movement arousals to explore the mechanisms by which biomechanical factors influence position preference. Forty-one mature-aged adults underwent 2 nights of at-home polysomnography ~2 weeks apart, on a standardised firm foam mattress, measuring nocturnal sleep architecture and position. The lateral supine ratio and restlessness indices specific to lateral and supine positions including limb movement index, limb movement arousal index, arousal index, wake index, respiratory arousal index and apnea-hypopnea index were calculated and analysed via linear mixed-effects regression. In the supine position, all restlessness indices were significantly increased compared with the lateral position, including a 379% increase in respiratory arousals (β = 7.0, p < 0.001), 108% increase in arousal index (β = 10.3, p < 0.001) and 107% increase in wake index (β = 2.5, p < 0.001). Wake index in the supine position increased significantly with more lateral sleep (β = 1.9, p = 0.0013), and significant correlation between lateral supine ratio polysomnography 1 and lateral supine ratio polysomnography 2 (β = 0.95, p < 0.001) indicated strong consistency in sleep preference. Overall, the findings suggest that some individuals have low tolerance to supine posture, represented by a comparatively high wake index in the supine position, and that these individuals compensate by sleeping a greater proportion in the lateral position.
关于决定睡眠时个体躺卧姿势偏好的生理和生物力学因素，人们知之甚少。本研究调查了姿势偏好与特定姿势的觉醒、醒来、肢体运动和肢体运动引起的觉醒之间的关系，以探索生物力学因素影响姿势偏好的机制。41名成年人在标准化的硬泡沫床垫上，相隔约2周在家中进行了两晚的多导睡眠监测，测量夜间睡眠结构和姿势。计算并通过线性混合效应回归分析了侧卧仰卧比例以及侧卧和仰卧姿势特有的不安指数，包括肢体运动指数、肢体运动引起的觉醒指数、觉醒指数、醒来指数、呼吸觉醒指数和呼吸暂停低通气指数。与侧卧姿势相比，仰卧姿势下所有不安指数均显著增加，包括呼吸觉醒增加379%（β = 7.0，p < 0.001）、觉醒指数增加108%（β = 10.3，p < 0.001）和醒来指数增加107%（β = 2.5，p < 0.001）。仰卧姿势下的醒来指数随着更多的侧卧睡眠而显著增加（β = 1.9, p = 0.0013），多导睡眠监测1的侧卧仰卧比例与多导睡眠监测2的侧卧仰卧比例之间存在显著相关性（β = 0.95，p < 0.001），表明睡眠偏好具有很强的一致性。总体而言，研究结果表明，一些个体对仰卧姿势耐受性较低，表现为仰卧姿势下相对较高的醒来指数，并且这些个体通过增加侧卧姿势的睡眠时间来进行补偿。
