Temporal associations between arousal and body/limb movement in children with suspected obstructed sleep apnoea

Abstract

The inter-relationship between arousal events and body and/or limb movements during sleep may significantly impact the performance and clinical interpretation of actigraphy. As such, the objective of this study was to quantify the temporal association between arousals and body/limb movement. From this, we aim to determine whether actigraphy can predict arousal events in children, and identify the impact of arousal-related movements on estimates of sleep/wake periods. Thirty otherwise healthy children (5-16 years, median 9 years, 21 male) with suspected sleep apnoea were studied using full polysomnography and customised raw tri-axial accelerometry measured at the left fingertip, left wrist, upper thorax, left ankle and left great toe. Raw data were synchronised to within 0.1 s of the polysomnogram. Movements were then identified using a custom algorithm. On average 67.5% of arousals were associated with wrist movement. Arousals associated with movement were longer than those without movement (mean duration: 12.2 s versus 7.9 s respectively, p < 0.01); movements during wake and arousal were longer than other sleep movements (wrist duration: 6.26 s and 9.89 s versus 2.35 s respectively, p < 0.01); and the movement index (movements/h) did not predict apnoea-hypopnoea index (ρ = -0.11). Movements associated with arousals are likely to unavoidably contribute to actigraphy's poor sensitivity for wake. However, as sleep-related movements tend to be shorter than those during wake or arousal, incorporating movement duration into the actigraphy scoring algorithm may improve sleep staging performance. Although actigraphy-based measurements cannot reliably predict all arousal events, actigraphy can likely identify longer events that may have the greatest impact on sleep quality.

A graphical method for comparing nocturnal oxygen saturation profiles in individuals and populations: Application to healthy infants and preterm neonates

“…Third, despite Masimo pulse oximeters using sophisticated artefact detection and removal algorithms, movement artefact will almost certainly be present in observed SpO 2 data, and may appear as apparent desaturation events. Our previous study indicated that these occur more frequently during wake, and therefore unless artefact periods are manually removed, unusual trends may present in children with extended wake periods or a particular propensity for movements during sleep . Ultimately, this graphical tool is not intended to be a stand‐alone diagnostic tool, but rather to present SpO 2 information in a more informative way.…”

“…Our previous study indicated that these occur more frequently during wake, 16 and therefore unless artefact periods are manually removed, unusual trends may present in children with extended wake periods or a particular propensity for movements during sleep. 43 Ultimately, this graphical tool is not intended to be a stand-alone diagnostic tool, but rather to present SpO 2 information in a more informative way.…”

Fitbit Sleep Measures in Children with and without Sleep Disordered Breathing

“…This finding suggests that children with SDB may compensate for their disturbed sleep by sleeping longer hours, particularly on the weekend when the severity of SDB and PSG movement measurements and a normalization of these after adenotonsillectomy. Additionally, some found children with OSA showed sleep patterns with consolidation of movement and sleep runs and suggested that movement distribution may be a more sensitive marker for sleep fragmentation, rather than frequency of movement alone [11,16]. Using actigraphy, Suratt, et al [26] investigated the relationship between nocturnal movements and neurocognitive performance in children with suspected SDB.…”

“…differences in sleep architecture between children with SDB and normal controls [7,9,10]. There is also evidence that children with SDB have a blunted EEG arousal response to respiratory stimuli and cortical arousals during PSG may not be sensitive enough to detect sleep disruption [11,12]. So although PSG may provide a diagnosis for children with severe SDB such as OSA, identifying those with milder disease who are also at risk for neurocognitive and behavioral impairment may be a challenge.…”

“…Most recently, nocturnal body movements have been proposed to be a more specific marker of sleep disturbance in children than adults due to age-related differences in sleep architecture and arousal processes [11,[13][14][15]. For some disease states associated with sleep disruption, studies have demonstrated that abnormal sleep-related body movements can occur with particular frequency and distribution [16].…”