Actigraphy analysis project
Predictive algorithms of individual wrist actigraphy for real life.
This project is looking for new ways of sleep/circadian data analysis.
The main target is to search for predictive algorithms from wrist actigraphy recordings of one subject using a MotionWatch8 (CamNtech Ltd) system on the non predominant wrist, for unrestricted lifestyle.
Wrist actigraphy has been used in the past 30 years to monitor motion activity.
The actigraphy data have been accepted for the analysis of sleep of a single night, with a quantification of sleep duration and its fragmentation.
They are also used to check the presence of fluctuations in the circadian cycle, especially to highlight pathologies with shifts of falling asleep timing.
During the day it is possible to quantify exercise and (with calibration) recognize type and intensity of the exercise.
Continuous monitoring of wrist actigraphy in real life is possible and it is a valuable tool.
Nowadays, the needed hardware is cheap and it is possible to imagine useful applications in real life, for continuous monitoring and smart homes.
There are dozens of startups with wearable monitors based on actigraphy that use more or less the same parameters for recording and analysis of one minute epochs. And then, they make the comparison against a(nother) so called "normal" group they built for the occasion, frozen in time and space.
Existing analysis methodologies for wrist actigraphy, describe the recorded data but do not provide any personal parameter, I mean something that alert or reassures about your body status, at least for the coming day, as well as we do for Temperature or Blood pressure measurements.
On the contrary, I think that for personal monitors we need personal parameters, that "grow old" with the subject, in his own way.
I think that for such parameters, we need to create data models and develop algorithms that use Artificial Intelligence.
Hopefully, the analysis of the long term, high sampling data of subproject 1 will allow researchers to find at least one parameter that will be possible to use. Anyway, even if that search fails, the need of the one second epoch in this field of studies is bubbling, and that recording will be useful.
The possible analysis will be tied to the lenght of the recording, but also on the models that will be invented for this new type of recording. It is something that need more than one research center and therefore the idea is to make the first year at one second epoch (Phase 2 and 3) available to the public.
Sub-project 1 – Dataset
New models and algorithms need long term data sets and guidelines on methodological issues. It seems that both are not easily available, on and off line.
Some examples are available in partially controlled environments:
- Nearly 600 days in 2 patients
Werth, Esther, Egemen Savaskan, Vera Knoblauch, Paola Fontana Gasio, Eus J.W. van Someren, Christoph Hock, Anna Wirz-Justice. Decline in long-term circadian rest-activity cycle organization in a patient with dementia. J Geriatr Psychiatry Neurol, 2002; Vol. 15; pp. 55-59.
- 50 days and then 30 days after 5 months
Miller, Nita Lewis, Shattuck, Lawrence, G. Sleep Patterns of Young Men and Women Enrolled at the United States military Academy: Results from Year 1 of a 4-Year Longitudinal Study. Sleep, 2005; Vol. 28; No. 7; p. 837.
- One month twice a year for 4 years
Longitudinal Study of Sleep Patterns of United States Military Academy Cadets
Nita Lewis Miller, Lawrence G. Shattuck, Panagiotis Matsangas
Sleep. 2010 December 1; 33(12): 1623–1631.
- 6 months sea duty
Nita Lewis Shattuck ; Panagiotis Matsangas
A 6-Month Assessment of Sleep During Naval Deployment: A Case Study of a Commanding Officer. Aerospace medicine and human performance Vol. 86, No. 5 May 2015
Few recordings are available in free life:
- 5 months, one patient
Garbazza C, Bromundt V, Eckert A,Brunner DP, Meier F, Hackethal S and Cajochen C (2016)
Non-24-Hour Sleep-Wake Disorder Revisited – A Case Study.
Front. Neurol. 7:17. doi: 10.3389/fneur.2016.00017
- 4 months, 80 OSA patients and 50 controls.
Sleep remains disturbed in patients with obstructive sleep apnea treated with positive airway pressure: a three-month cohort study using continuous actigraphy
Sleep Medicine, Volume 24, August 2016, Pages 24-31 Jon Tippin, Nazan Aksan, Jeffrey Dawson, Steven W. Anderson, Matthew Rizzo
- And the amazing 30 years!
ESRS 2016 Bologna
P041 Three decades of continuous motor activity recording:analysis of sleep duration
A. Borbely, T. Rusterholz and P. Achermann Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland
Objectives: Motor activity recording by a wrist-worn device is a common unobtrusive method to monitor the rest-activity cycle. We present a first analysis of data that have been obtained over more than three decades.
To answer to the need of a suitable data set, I started one long term recording on myself, late 2015. Since it is expected from physiology to find rhythms with a period long at least one year, a recording with a minimum length of two years is today the first target.
Sub-project 1 – Dataset – Phase I
That was the baseline. Six months at 1 minute epoch. Start date 17/12/2015
Sub-project 1 – Dataset – Phase II
Six months at 1 second epoch.
Sub-project 1 – Dataset – Phase III
Six months at 1 second epoch.Environnement change: ligh only wake up clock stopped. It was set at 7.00, at about 3 meters from the head.
Sub-project 1 – Dataset – Phase IV
Six months at 1 second epoch. In case of early morning (4 to 6 a.m) wake up, most of the time an eye mask is then used.
Sub-project 1 – Dataset – Phase V
Six months at 1 second epoch. It is the last Phase needed to reach the minimun of 2 years continous regording at 1 sec.
At the moment it is not known what should be a "sufficient" lenght of such a recording, since it is the first set ever recorded, I think it should go ahead as long as possible, because it will show in one subject the change over time that is expected from short recordings in groups of different ages described in literature.
Subproject 1 - Recording Log
The epoch recording value was set at one minute. For the meaning of data sampling and units see this page.
Beside movement data, there are light levels read by the instrument. Please note that it is not possible to know if and when the instrument is covered by garments.
The Marker option is used to signal when the instrument is taken off. It is inserted at the beginning and at the end of a flat period, sometimes only at the beginning or at the end. It is possible that sometimes the marker button was not pressed properly. If so, it should be only in the morning or at data download, always only for few minutes.
Phase II- Start day 17/06/2016
From now on the epoch will be one second. That will require a data dowload each day and the risk of data loss is higher.
Month 7 - Closed with only 2 days lost.
Month 8 - Closed
Month 9 - Closed
Month 10 - Closed
Month 11 - Closed - Back to standard time-
Month 12 - End
The main risk is that the subject will not accept to carry on the recording, for unknown reason. The fact that I'm the researcher and the subject lowers the risk. There are few ways for the subject to influence the data and nearly no one for the more interesting part, that is the sleep at night. That lowers possible bias from the researcher.
After the first year, it seems that 10% of raw data are lost due to mismanagement of the recording unit by the subject. The two main reasons are data not downloaded and battery life shorter than expected. For the latter, now the battery is changed when it reaches 30% of the full charge.
Phase III - Start day 17/12/2016
Month 13 - Closed
Month 14 - Closed
Month 15 – Closed
Month 16 - Closed - Change of local time, +1 from the first 3 months
Month 17 - Closed
Month 18 - Closed
Phase IV - Start day 19/06/2017
Month 19 - Closed
Month 20 - Closed
Month 21 - Closed
Month 22 - Closed - Back to standard time-
Month 23 - Closed
Month 24 - Closed - 3 days of core temperature monitoring
Phase V - Start day 17/12/2017
Month 25 - Closed
Month 26 - Closed
Month 27 - Closed
Month 28 - Closed - Change of local time, +1 from the first 3 months
Month 29 - Closed
Month 30 - Closed