1
|
Heglum HSA, Kallestad H, Vethe D, Langsrud K, Sand T, Engstrøm M. Distinguishing sleep from wake with a radar sensor: a contact-free real-time sleep monitor. Sleep 2021; 44:zsab060. [PMID: 33705555 PMCID: PMC8361351 DOI: 10.1093/sleep/zsab060] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 02/07/2021] [Indexed: 11/17/2022] Open
Abstract
This work aimed to evaluate whether a radar sensor can distinguish sleep from wakefulness in real time. The sensor detects body movements without direct physical contact with the subject and can be embedded in the roof of a hospital room for completely unobtrusive monitoring. We conducted simultaneous recordings with polysomnography, actigraphy, and radar on two groups: healthy young adults (n = 12, four nights per participant) and patients referred to a sleep examination (n = 28, one night per participant). We developed models for sleep/wake classification based on principles commonly used by actigraphy, including real-time models, and tested them on both datasets. We estimated a set of commonly reported sleep parameters from these data, including total-sleep-time, sleep-onset-latency, sleep-efficiency, and wake-after-sleep-onset, and evaluated the inter-method reliability of these estimates. Classification results were on-par with, or exceeding, those often seen for actigraphy. For real-time models in healthy young adults, accuracies were above 92%, sensitivities above 95%, specificities above 83%, and all Cohen's kappa values were above 0.81 compared to polysomnography. For patients referred to a sleep examination, accuracies were above 81%, sensitivities about 89%, specificities above 53%, and Cohen's kappa values above 0.44. Sleep variable estimates showed no significant intermethod bias, but the limits of agreement were quite wide for the group of patients referred to a sleep examination. Our results indicate that the radar has the potential to offer the benefits of contact-free real-time monitoring of sleep, both for in-patients and for ambulatory home monitoring.
Collapse
Affiliation(s)
- Hanne Siri Amdahl Heglum
- Department of Neuromedicine and Movement Science, Norwegian University of Science and Technology, Trondheim, Norway
- Novelda AS, Trondheim, Norway
| | - Håvard Kallestad
- Department of Mental Health, Norwegian University of Science and Technology, Trondheim, Norway
- Division of Mental Health Care, St. Olavs University Hospital, Trondheim, Norway
| | - Daniel Vethe
- Department of Mental Health, Norwegian University of Science and Technology, Trondheim, Norway
- Division of Mental Health Care, St. Olavs University Hospital, Trondheim, Norway
| | - Knut Langsrud
- Department of Mental Health, Norwegian University of Science and Technology, Trondheim, Norway
- Division of Mental Health Care, St. Olavs University Hospital, Trondheim, Norway
| | - Trond Sand
- Department of Neuromedicine and Movement Science, Norwegian University of Science and Technology, Trondheim, Norway
- Department of Neurology and Clinical Neurophysiology, St. Olavs University Hospital, Trondheim, Norway
| | - Morten Engstrøm
- Department of Neuromedicine and Movement Science, Norwegian University of Science and Technology, Trondheim, Norway
- Department of Neurology and Clinical Neurophysiology, St. Olavs University Hospital, Trondheim, Norway
| |
Collapse
|
2
|
Vethe D, Scott J, Engstrøm M, Salvesen Ø, Sand T, Olsen A, Morken G, Heglum HS, Kjørstad K, Faaland PM, Vestergaard CL, Langsrud K, Kallestad H. The evening light environment in hospitals can be designed to produce less disruptive effects on the circadian system and improve sleep. Sleep 2021; 44:5909282. [PMID: 32954412 PMCID: PMC7953207 DOI: 10.1093/sleep/zsaa194] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 09/02/2020] [Indexed: 01/12/2023] Open
Abstract
STUDY OBJECTIVES Blue-depleted lighting reduces the disruptive effects of evening artificial light on the circadian system in laboratory experiments, but this has not yet been shown in naturalistic settings. The aim of the current study was to test the effects of residing in an evening blue-depleted light environment on melatonin levels, sleep, neurocognitive arousal, sleepiness, and potential side effects. METHODS The study was undertaken in a new psychiatric hospital unit where dynamic light sources were installed. All light sources in all rooms were blue-depleted in one half of the unit between 06:30 pm and 07:00 am (melanopic lux range: 7-21, melanopic equivalent daylight illuminance [M-EDI] range: 6-19, photopic lux range: 55-124), whereas the other had standard lighting (melanopic lux range: 30-70, M-EDI range: 27-63, photopic lux range: 64-136), but was otherwise identical. A total of 12 healthy adults resided for 5 days in each light environment (LE) in a randomized cross-over trial. RESULTS Melatonin levels were less suppressed in the blue-depleted LE (15%) compared with the normal LE (45%; p = 0.011). Dim light melatonin onset was phase-advanced more (1:20 h) after residing in the blue-depleted LE than after the normal LE (0:46 h; p = 0.008). Total sleep time was 8.1 min longer (p = 0.032), rapid eye movement sleep 13.9 min longer (p < 0.001), and neurocognitive arousal was lower (p = 0.042) in the blue-depleted LE. There were no significant differences in subjective sleepiness (p = 0.16) or side effects (p = 0.09). CONCLUSIONS It is possible to create an evening LE that has an impact on the circadian system and sleep without serious side effects. This demonstrates the feasibility and potential benefits of designing buildings or hospital units according to chronobiological principles and provide a basis for studies in both nonclinical and clinical populations.
Collapse
Affiliation(s)
- Daniel Vethe
- Department of Mental Health, Norwegian University of Science and Technology, Trondheim, Norway.,Division of Mental Health Care, St. Olav's University Hospital, Trondheim, Norway
| | - Jan Scott
- Department of Mental Health, Norwegian University of Science and Technology, Trondheim, Norway.,Institute of Neuroscience, University of Newcastle, Newcastle, UK
| | - Morten Engstrøm
- Department of Neuromedicine and Movement Science, Norwegian University of Science and Technology, Trondheim, Norway.,Department of Clinical Neurophysiology, St. Olav's University Hospital, Trondheim Norway
| | - Øyvind Salvesen
- Unit of Applied Clinical Research, Norwegian University of Science and Technology, Trondheim, Norway
| | - Trond Sand
- Department of Neuromedicine and Movement Science, Norwegian University of Science and Technology, Trondheim, Norway.,Department of Clinical Neurophysiology, St. Olav's University Hospital, Trondheim Norway
| | - Alexander Olsen
- Department of Psychology, Norwegian University of Science and Technology, Trondheim, Norway.,Department of Physical Medicine and Rehabilitation, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway
| | - Gunnar Morken
- Department of Mental Health, Norwegian University of Science and Technology, Trondheim, Norway.,Division of Mental Health Care, St. Olav's University Hospital, Trondheim, Norway
| | - Hanne S Heglum
- Department of Neuromedicine and Movement Science, Norwegian University of Science and Technology, Trondheim, Norway.,Novelda AS, Trondheim, Norway
| | - Kaia Kjørstad
- Department of Mental Health, Norwegian University of Science and Technology, Trondheim, Norway.,Division of Mental Health Care, St. Olav's University Hospital, Trondheim, Norway
| | - Patrick M Faaland
- Department of Mental Health, Norwegian University of Science and Technology, Trondheim, Norway.,Division of Mental Health Care, St. Olav's University Hospital, Trondheim, Norway
| | - Cecilie L Vestergaard
- Department of Mental Health, Norwegian University of Science and Technology, Trondheim, Norway.,Division of Mental Health Care, St. Olav's University Hospital, Trondheim, Norway
| | - Knut Langsrud
- Department of Mental Health, Norwegian University of Science and Technology, Trondheim, Norway.,Division of Mental Health Care, St. Olav's University Hospital, Trondheim, Norway
| | - Håvard Kallestad
- Department of Mental Health, Norwegian University of Science and Technology, Trondheim, Norway.,Division of Mental Health Care, St. Olav's University Hospital, Trondheim, Norway
| |
Collapse
|
3
|
Scott J, Langsrud K, Goulding IR, Kallestad H. Let there be blue-depleted light: in-patient dark therapy, circadian rhythms and length of stay. BJPSYCH ADVANCES 2020. [DOI: 10.1192/bja.2020.47] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
SUMMARYLight is the most important environmental influence (zeitgeber) on the synchronization of the circadian system in humans. Excess light exposure during the evening and night-time affects secretion of the hormone melatonin, which in turn modifies the temporal organization of circadian rhythms, including the sleep–wake cycle. As sleep disturbances are prominent in critically ill medical and psychiatric patients, researchers began to examine the impact of light exposure on clinical outcomes and length of hospitalization. In psychiatric inpatients, exposure to bright morning light or use of blue blocking glasses have proved useful interventions for mood disorders. Recently, knowledge about light and the circadian system has been applied to the design of inpatient facilities with dynamic lighting systems that change according to time of day. The installation of ‘circadian lighting’ alongside technologies for monitoring sleep–wake patterns could prove to be one of the most practical and beneficial innovations in inpatient psychiatric care for more than half a century.
Collapse
|
4
|
Okkels N, Jensen LG, Skovshoved LC, Arendt R, Blicher AB, Vieta E, Straszek S. Lighting as an aid for recovery in hospitalized psychiatric patients: a randomized controlled effectiveness trial. Nord J Psychiatry 2020; 74:105-114. [PMID: 31603013 DOI: 10.1080/08039488.2019.1676465] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Purpose: Artificial indoor lighting can disturb sleep and increase depressive symptoms; both common complaints in psychiatric inpatients. In this trial we aimed to improve sleep in psychiatric inpatients using a circadian lighting environment.Patients and methods: Investigator-blinded parallel-group randomised controlled effectiveness trial in an inpatient psychiatric ward with adjustable lighting. Admitted patients received a pre-set circadian lighting environment (intervention group) or lighting as usual (control group). The primary outcome was the Pittsburg Sleep Quality Index (PSQI) and secondary outcomes included the Major Depression Inventory and WHO-5 Well-Being Index.Results: We assessed 74 patients and included 54 (27 treated and 27 controls). Treated patients reported a non-significant change in mean sleep quality by -1.02 points on the PSQI (95% CI: -3.17; 1.12) and controls by -0.59 points (95% CI: -2.52; 1.33), difference -0.43 (95% CI: -3.05; 2.2, p-value .74). Similarly, treated patients reported a non-significant change in depressive symptoms and well-being compared to controls. Qualitative data indicated no serious side-effects and no patients in the intervention group were submitted to involuntary measures. Collection of data was non-complete and missing data from self-reported questionnaires amounted to 52.5%.Conclusions: The intervention showed no effect on sleep quality, mood or well-being. The circadian lighting environment was safe in our small and diverse patient sample. The trial integrated well with routine clinical care and our sample reflected the heterogeneity of the target population.
Collapse
Affiliation(s)
- Niels Okkels
- Department of Affective Disorders, Aarhus University Hospital Risskov, Aarhus, Denmark
| | | | | | - Runhild Arendt
- Department of Affective Disorders, Aarhus University Hospital Risskov, Aarhus, Denmark
| | - Anne Bastholm Blicher
- Department of Affective Disorders, Aarhus University Hospital Risskov, Aarhus, Denmark
| | - Eduard Vieta
- Hospital Clinic, Institute of Neuroscience, University of Barcelona, IDIBAPS, CIBERSAM, Barcelona, Catalonia, Spain
| | - Sune Straszek
- Department of Affective Disorders, Aarhus University Hospital Risskov, Aarhus, Denmark.,Bipolar Disorder Unit, Psychiatry, Aalborg University Hospital, Aalborg, Denmark
| |
Collapse
|