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. 2024 Apr 3;11(4):352.
doi: 10.3390/bioengineering11040352.

Sleeping for One Week on a Temperature-Controlled Mattress Cover Improves Sleep and Cardiovascular Recovery

Nicole E Moyen  1 , Tatiana R Ediger  1 , Kathryn M Taylor  2 , Erin G Hancock  1 , Lucas D Holden  1 , Emma E Tracy  1 , Philip H Kay  1 , Charles R Irick  1 , Kevin J Kotzen  1 , David D He  1
Affiliations

Sleeping for One Week on a Temperature-Controlled Mattress Cover Improves Sleep and Cardiovascular Recovery

Nicole E Moyen et al. Bioengineering (Basel). .

Abstract

Body temperature should be tightly regulated for optimal sleep. However, various extrinsic and intrinsic factors can alter body temperature during sleep. In a free-living study, we examined how sleep and cardiovascular health metrics were affected by sleeping for one week with (Pod ON) vs. without (Pod OFF), an active temperature-controlled mattress cover (the Eight Sleep Pod). A total of 54 subjects wore a home sleep test device (HST) for eight nights: four nights each with Pod ON and OFF (>300 total HST nights). Nightly sleeping heart rate (HR) and heart rate variability (HRV) were collected. Compared to Pod OFF, men and women sleeping at cooler temperatures in the first half of the night significantly improved deep (+14 min; +22% mean change; p = 0.003) and REM (+9 min; +25% mean change; p = 0.033) sleep, respectively. Men sleeping at warm temperatures in the second half of the night significantly improved light sleep (+23 min; +19% mean change; p = 0.023). Overall, sleeping HR (-2% mean change) and HRV (+7% mean change) significantly improved with Pod ON (p < 0.01). To our knowledge, this is the first study to show a continuously temperature-regulated bed surface can (1) significantly modify time spent in specific sleep stages in certain parts of the night, and (2) enhance cardiovascular recovery during sleep.

Keywords: polysomnography; sex differences; sleep quality; sleep satisfaction; temperature regulation; thermal comfort zone; thermoregulation.

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Conflict of interest statement

This study was funded by Eight Sleep, Inc. Authors N.E.M., D.D.H., T.R.E., K.J.K., E.E.T. and C.R.I. are currently paid employees of the company. Authors N.E.M., D.D.H., T.R.E., K.J.K., E.E.T. and C.R.I. hold shares in the company but otherwise declare no non-financial competing interests. Authors K.M.T. and E.H. were paid consultants for Eight Sleep, Inc., but declare no non-financial competing interests. Authors L.H. and P.H.K. were previously paid employees of Eight Sleep, Inc.

Figures

Figure 1
Figure 1
Experimental Design Schematic. Subjects (n = 54) spent the first seven nights with temperature regulation off (Pod OFF Baseline) and then spent seven nights with temperature regulation on (Pod ON), followed by the last two nights with temperature regulation off (Pod OFF End). “No Pod Cover” means that subjects slept on their own bed without the Pod cover installed. “Pod Cover” means that subjects were sleeping with the Pod cover on their bed, either with the temperature regulation on or off. Sleep stages, sleep onset latency (SOL), sleep efficiency (SE), and total sleep time (TST) were recorded on Nights 6–9 and 13–16 through a home sleep test device (HST). Throughout the entire study, sleeping HR and HRV, along with daily exercise, were recorded via a Fitbit. Ratings of perceptual comfort and sleep quality were recorded via a daily morning survey.
Figure 2
Figure 2
Changes in HR and HRV based on Pod temperature status. Means ± SE for minimum sleeping HR and median sleeping HRV at Pod OFF Baseline, Pod ON, and Pod OFF End stratified by sex (females in orange and males in purple). * Indicates a significant difference in linear mixed models from Pod OFF Baseline at p < 0.05.
Figure 3
Figure 3
Changes in sleep latency metrics from Pod OFF to ON for cool vs. warm Bedtime temperatures. Mean difference and 95% confidence intervals for the change in sleep onset latency (SOL) and Deep SOL metrics from Pod OFF Baseline vs. Pod ON sleeping at cool or warm Bedtime temperatures, stratified by sex. REM SOL represents the mean difference from Pod OFF to cool vs. warm Early-Phase temperatures. * Indicates a significant difference from Pod OFF Baseline at p < 0.05. ‡ Indicates trend towards being significantly different from Pod OFF Baseline at p < 0.10.
Figure 4
Figure 4
Changes in absolute sleep stage duration based on cool vs. warm sleepers in Early and Late Phases. Boxplots depicting distributions of changes in time (min) spent in each sleep stage for Pod OFF vs. cool (blue) or warm (red) temperatures during the Early and Late Phases for females (A) and males (B). The black diamonds denote sample means, and the horizontal lines within the boxes denote medians. The dotted line at 0 indicates no change from Pod OFF Baseline to Pod ON. * Indicates a significant difference in linear mixed models from Pod OFF Baseline at p < 0.05, and ‡ indicates trending toward significance at p < 0.10.
Figure 5
Figure 5
Changes in the percentage of total sleep time spent in each sleep stage based on cool vs. warm temperatures in Early and Late Phases. Boxplots depicting distributions of changes in the percentage of time spent in each sleep stage for Pod OFF vs. cool (blue) or warm (red) temperatures. Early Phase (left-hand panels) and Late Phase (right-hand panels) are separated for females (A) and males (B). The black diamonds denote means, and the horizontal lines within the boxes denote medians. The dotted line at 0 indicates no change from Pod OFF Baseline to Pod ON. * Indicates a significant difference in linear mixed models from Pod OFF Baseline at p < 0.05, and ‡ indicates trending toward significance at p < 0.10.
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References

    1. Rasch B., Born J. About sleep’s role in memory. Physiol. Rev. 2013;93:681–766. doi: 10.1152/physrev.00032.2012. - DOI - PMC - PubMed
    1. Walker M.P. The role of slow wave sleep in memory processing. J. Clin. Sleep Med. 2009;5((Suppl. S2)):S20–S26. doi: 10.5664/jcsm.5.2S.S20. - DOI - PMC - PubMed
    1. Perry G.S., Patil S.P., Presley-Cantrell L.R. Raising awareness of sleep as a healthy behavior. Prev. Chronic Dis. 2013;10:E133. doi: 10.5888/pcd10.130081. - DOI - PMC - PubMed
    1. Robbins R., Quan S.F., Weaver M.D., Bormes G., Barger L.K., Czeisler C.A. Examining sleep deficiency and disturbance and their risk for incident dementia and all-cause mortality in older adults across 5 years in the United States. Aging. 2021;13:3254–3268. doi: 10.18632/aging.202591. - DOI - PMC - PubMed
    1. Sharma S., Kavuru M. Sleep and metabolism: An overview. Int. J. Endocrinol. 2010;2010:270832. doi: 10.1155/2010/270832. - DOI - PMC - PubMed

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