Assessing Sleep Wearables and In-Bedroom Devices: CTA Standards Work

Presentation on theme: "Assessing Sleep Wearables and In-Bedroom Devices: CTA Standards Work"— Presentation transcript:

1 Assessing Sleep Wearables and In-Bedroom Devices: CTA Standards Work
Max Hirshkowitz, PhD, D ABSM NSF, Immediate Past Chairman of Board Baylor College of Medicine, Full Professor (Emeritus Stanford University, Consulting Professor

2 Disclosure Max Hirshkowitz, PhD, has no relevant financial relationships to disclose and does not intend to discuss the off-label/investigative use of any medication.

3 Educational Objectives
Upon concluding this activity, participants should be able to... To review basic concepts concerning terminology, regulatory issues, measurement, and statistics To summarize adopted CTA standards and the current status of the currently ongoing work group project

4 Lessons From History

5 Remember… No Technology Starts Out Perfect

6 But… Technology Improves Over Time
Then Now

7 And then there are obstructionists

8 1936 The first overnight Polysomnograph Machine Loomis Labs in
Tuxedo Park, NY

9 In Silicon Valley Parlance… In the late 1970’s Polysomnography became the Killer App for diagnosing Sleep Apnea

10 Sleep laboratory control room, circa 1979

11 Digital PSG Arrives… Finally 1984

12 Sleep laboratory control room, circa 2009

13 But… Then along came HST (Home Sleep Testing)

14 The Future Isn’t What It Used To Be

15 The War Between PSG & HST Began as the New Millennium Dawned
VS

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17 The PSG War Against HST was Lost in 2008

18 The Problem Now is That the Baby Got Thrown Out With the Bathwater

19 CTA/ANSI Standards Project for Wearable & In-bedroom Sleep Trackers.
The project has three parts Phase I: Definitions and Informatics Phase II: Methods Phase III: Performance and Validation Criteria

20 So… What are the Objections to Wearable & In-bedroom Sleep Trackers?
I don’t know what the data mean The data are unreliable I don’t want to be bothered with it because of A & B because the tools I use now are fine… if it ain’t broke, don’t fix it I don’t have any way to bill for it

21 So… What are the Objections to Wearable & In-bedroom Sleep Trackers?
I don’t know what the data mean The data are unreliable I don’t want to be bothered with it because of A & B because the tools I use now are fine… if it ain’t broke, don’t fix it I don’t have any way to bill for it The CTA/ANSI Standards Project was commissioned to answer objections A & B & by extension C.1

22 Phase I: Definitions & Informatics
ANSI/CTA Standard Definitions and Characteristics for Wearable Sleep Monitors ANSI/CTA/NSF September 2016

23 Five Categories of Terms
Terms in Category A: Terms describing a sleep episodes temporal surround. These are general terms related to the sleeper’s intention and their position in the environment. Because a person may be in bed without an intention to sleep leads to the distinction between these two elements. Terminology Category Elemental Measure Derived Measures A General terms describing the temporal surround of a sleep episode Time when individual began Attempting To Sleep (TATS): TATS Start Time TATS End Time Time In Bed (TIB): TIB Start Time TIB End Time Total TATS Duration Total TIB Duration

24 Five Categories of Terms
Terms in Category B: Terms describing the general sequence of events once there is intention to sleep. Continued wakefulness and eventual sleep will occur. It should be noted that some of the terms in category B have both general and laboratory definitions. However, terms such as wakefulness do not require polysomnographic comparison to verify (e.g., I am awake while I am typing this document). BB General terms describing basic features of wakefulness and sleep Awake Asleep Awakening from sleep Brief awakening Brief moment of sleep (dozing) Total sleep period duration (TSPD) Total sleep time (TST) Sleep maintenance % Total wakefulness duration Wakefulness duration after initial sleep onset Number of awakenings Number of brief awakenings Awakening rate per hour Sleep fragmentation rate Number of dozing episodes

25 Five Categories of Terms
Terms in Category C: Once the initial sleep and final wakefulness episode determined, One can designate several important metrics based on the relationship between these measures and the temporal surround. These include latency to sleep onset, latency to arising, and sleep efficiency. Terms derived from basic features of wakefulness, sleep as they relate to the sleep episode and its surround Initial sleep onset time Final awakening time Latency to sleep onset Latency to arising Sleep efficiency %

26 Five Categories of Terms
Terms in Category D: These terms are defined in the “AASM manual for the scoring of sleep and associated events: rules, terminology and technical specifications. 1st edition” (Iber et al, 2007) and updated by subsequent revisions. This nomenclature is well established and widely used by sleep researchers and sleep medicine practitioners. These standards are based on polysomnographic (electroencephalogram, electrooculogram, and electromyogram) correlates derived from normal human subjects. To avoid creating linguistic ambiguity, these terms should concord with standardized definitions and will not be redefined here. Specific terms describing processes occurring during sleep based on polysomnography REM Sleep N1 N2 N3 CNS Arousal Number of CNS arousals CNS arousal rate per hour Duration, percentage (of TST), and latency from sleep onset for each of the following: REM

27 Five Categories of Terms
Terms in Category E: Terms proposed here are designed to extend sleep feature description beyond existing standard nomenclature. Alternative terminology is recommended to avoid creating ambiguity with existing polysomnographic nomenclature (provided in category D). Care was taken to avoid using sleep medicine laboratory terminology in order to avoid confusion Alternate terms for subdividing sleep into different processes Dream sleep Core Sleep Sound Sleep Restless Sleep Duration and percentage for each of the following: Core sleep Restless sleep % of TST

28 Five Categories of Terms
Terms in Category F: Terms used to describe circadian rhythms are included here. Wrist actigraphs have long been used in circadian rhythm research. Each actigraph differs with respect to precision and accuracy; consequently, each should be evaluated independently. Terms used to describe the sleep-wake cycle over time periods exceeding 7 days Circadian Amplitude Circadian Period length (tau) Circadian Phase Relative duration of the active period compared to the dormant period

29 Phase II: Sleep Tracking Methods
Self-Report Direct or Video Observation Room/Bed Sensors Actigraphy (Movement Sensors) Polysomnography (EEG-EOG-EMG) Eye Movements (Piezo-Electric, EOG, Room Sensors) Autonomic Nervous System Measures BP Blood Pressure EDA Electrodermal Activity HR Heart Rate and Regularity Respiratory Rate & Variability Body Temperature Endocrine Variations

30 Phase II: Sleep Tracking Methodology
Notation: D- Directly Measured; I- Inferred from measure indicated; S- Sleep medicine standard Self-Report Observation Room/Bed Sensors Actigraphy PSG ANS Body Temp Endocrine TATS Start Time D I TATS End Time TIB Start Time TIB End Time Awake S Asleep Awakening from Sleep Brief Awakening Initial Sleep Onset Time Final Awakening Time Brief Moment of Sleep (Dozing) REM Sleep N1 Sleep N2 Sleep N3 Sleep CNS Arousal Dream Sleep Core Sleep Restless Sleep Sound Sleep Circadian Amplitude Circadian Period Length (tau) Circadian Phase

31 Phase III: Performance Criteria
Different terms require different criteria (e.g., stages vs. circadian) Different terms require different environmental and test conditions Sample considerations or each measure Number of subjects Male and female Age group Good vs. Poor Sleepers Undiagnosed vs. Diagnosed With Sleep Disorders With medical, neurological, or psychiatric conditions

32 Phase III: Performance Criteria
Design & Statistics: Comparisons require temporal concordance (not overall composite agreement) Paradigm: Passive monitoring & comparison with a standard Temporal agreement during an intervention (eg. Forced awakening) Agreement with self-report after a spontaneous event (“I’m awake”) Experiments in nature

33 Validation must be performed against a reliable reference standard

34 … How reliable does it have to be?

35 The Problem with Correlations

36 What’s Wrong with Using Overall Agreement?

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41 Phase III: Performance Criteria
Design & Statistics: Comparisons require temporal concordance (not overall composite agreement) Paradigm: Passive monitoring & comparison with a standard Temporal agreement during an intervention (e.g. Forced awakening) Agreement with self-report after a spontaneous event (“I’m awake”) Experiments in nature

42 Wearable Self-monitoring Technology

43 Phase III: Performance Criteria
To date, I’ve found only 11 peer- reviewed journal articles addressing consumer wearable devices’ performance Research reports varied widely with respect to their methods, terminology, standards for testing & sample characteristics Agreement rates varied

44 So… what is the current status of the CTA Standards Project for Wearable & In-bedroom Sleep Trackers? Phase I: Definitions and Informatics- Complete Phase II: Methods- Complete Phase III: Performance and Validation Criteria- Currently On-going

45 So What? Who Cares? Consistent self-monitoring is key for behavior change. This includes: improved nutrition fitness weight loss Wearable or In-bed technology can provide self- monitoring for sleep (like a bathroom scale does for weight)

46 Final Considerations:
These devices are pretty good at estimating Sleep Duration, Awakenings, Restlessness, and Sleep Timing They are getting better at assessing Sleep vs. wakefulness in normal individuals Given the NSF Sleep Quality Project findings showing little agreement about sleep stage contribution, these devices may be able to estimate sleep quality Thus, if Sleep Health’s elements are: sleep duration sleep quality sleep satisfaction (which an individual assesses) absence of sleep disorders… We are 3/4ths of the way there.

47 Educational Objectives
Participants should now be able to... To review basic concepts concerning terminology, regulatory issues, measurement, and statistics To summarize adopted CTA standards and the current status of the currently ongoing work group project

48 Thank You