Sleep Monitoring
What is Actigraphy?
Actigraphy is an objective, ambulatory monitoring method for
tracking a patient’s sleep/wake activity patterns over time.
Monitoring is done with an actigraph device.
An actigraph device is
worn continuously like a standard wristwatch. It can be used in
the comfort of the patient’s own home, for multiple days and
nights. The device is noninvasive and
can be worn easily, 24/7, by almost all patient populations.
It’s especially useful when self-reporting is not an option, as
with patients who cannot accurately or reliably self-report
sleep information. Actigraphy analysis provides sleep schedule
variability, sleep
quantity and quality statistics, and daytime activity patterns
for weeks at a time. It has been widely used and well validated
in the field of sleep research for years. The long-term data
collected from the home environment by actigraphy also provides
sleep efficiency, total sleep time and sleep start and end times
not available from any other methods.
Actiwatch Family of
Ambulatory Actigraphy Devices:
 Actiwatches
are small, rugged, actigraphy-based data loggers that record a
digitally integrated measure of gross motor activity. Each model
of Actiwatch actigraph is equipped with a highly sensitive
accelerometer as well as the ability to record additional data
channels. The Actiwatch
Score, Actiwatch-2,
and Actiwatch Spectrum
use actigraphy principles to provide sleep schedule variability,
sleep quantity and quality statistics and daytime activity
patterns so you can better identify therapeutic options and
understand responses to treatment for patients. All three models
collect reliable, objective data on sleep/wake patterns for
multiple days in a subject’s ambulatory environment with the
comfort and aesthetics of a standard wrist watch.
Activity level is recognized as a valuable indicator for
medical problems and can provide answers to many research
questions. Activity levels correlate with sleep/wake patterns,
pain level, mood, energy expenditure, fatigue/alertness and
other quantifiable parameters. An Actiwatch actigraph also
provides an objective record for tracking and documenting normal
and abnormal sleep/wake patterns.
Two examples of the use of the Actiwatch are:
Sleep/Wake Patterns and General Activity Level
A digitally integrated recording of wrist
activity is a reliable indicator of Sleep/Wake state. The
Actiwatch is an actigraphy device that is the size of a standard
wrist watch. It allows for the recording of the smallest
movements for days, weeks, or even months.
When worn on the wrist, an Actiwatch actigraph can generate
an Activity record like the one shown below to be used as a tool
to document:
-
Sleep/Wake Patterns
-
Sleep Disorders
-
Circadian Rhythms Disorders
-
Disturbances brought on by Shift WorkReal time impedance
display
-
Basic Activity Levels
-
Compliance with Exercise Routines
Actogram Examples
Normal Sleeper
Humans typically display a pronounced decrease
in activity during rest. Rest periods
are characterized by small intermittent
movements while active periods show significant,
constant movement. Rest and activity together
display a pattern that is relatively
stable over the 24-hour-day for normal sleepers.
In the example to the right, from a typical
normal sleeper, a relatively stable rest
activity cycle is shown. The actogram is a
graphical tool that allows for the rapid
identification of this 24-hour pattern. Activity
during these periods is reduced when compared to
the active periods. Additionally, rest
periods commonly occur between 2100 hours and
0800 hours with some variation
for weekends.
|
 Click
to enlarge
Black= Activity periods
Aqua = rest periods |
Sleep Statistics for a Normal Sleeper
Sleep Statistics for identified sleep intervals are
generated by scoring algorithms validated in patients
with sleep disorders and infants. When used along with
the actogram, these statistics provide objective
documentation of sleep history to help shape treatment
strategies during diagnosis, treatment and follow up.
This objective evidence is used to inform the patient of
the impact of behavioral, social, or environmental
factors upon sleep patterns, quantity, and quality.
Commonly Used Statistics:
Sleep Time, Sleep Efficiency, Wake After Sleep Onset,
Number of Wake Bouts, Sleep Onset Latency.
|
Click to enlarge |
Insomniac
|
For patients with sleep disorders, rest and activity
data
display an unstable or shifted pattern that is easy to
see
on an actogram. Activity depicts elevated levels at just
about any time of day. Rest periods are variable in
length and timing.
|
Click to enlarge
Black= Activity periods
Aqua = rest periods |
Shift Work Sleep Disorder
|
Individuals required to alter their pattern of
sleep/wake in order to work at jobs with variable hours
can also be tracked using the Actiwatch device. It is
easy to see not
only the
drastic changes in timing of the active periods, but
also the fragmentation of consolidated sleep periods
surrounding shift changes.
|
Click to enlarge
Black= Activity periods
Aqua = rest periods
|
Citations:
The International Classification of Sleep Disorders
Diagnostic and Coding Manual 2nd Edition American
Academy of Sleep Medicine, Westchester, Illinois. 2005
Click
here for a list of papers where Actiwatch was used.
Other actogram examples are available
here on pages 2 to 4.
Follow this link
to request a complete price list.
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