Delayed Sleep Phase Syndrome and Actigraphy

Last updated: April 24, 2019

The information on this website is not intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice. Read our full medical disclaimer.

Delayed sleep-wake phase disorder (DSP) is a sleep disorder. It belongs to the group called Circadian Rhythm Disorders. When a person has DSP, there is a delay in their sleep pattern by two or more hours. The delay is not just when a person tries to go to sleep. There is also a delay when the person wakes up. This is a result of a shift in the person’s Circadian Rhythm or internal body clock. It means that the body clock gets shifted later at night and later in the morning.

Unlike with other sleep disorders, a person with DSP has a normal length of sleep. The problem is that the sleep pattern of that person is later than what he desires. This sleep pattern is also not what many consider as socially acceptable.

Someone with DSP is more likely to prefer late sleeping times and late wake-up times. Most of the time, a person with DSP has difficulty falling asleep until late at night. That person also has a hard time getting out of bed in the morning. This can lead to problems since the said person may have difficulty getting to school or work on time. Delayed Sleep Phase Syndrome can also lead to fatigue and excessive sleepiness.

What is an actigraph?

Actigraphy is a means of monitoring human rest or sleep cycles. This is a non-invasive method. It doesn’t require any surgery or intrusion in the patient’s body. When it comes to diagnosing sleep disorders, doctors often use a small actigraph unit. This actigraph unit or actimetry sensor usually comes in the form of a small wrist-worn device. It looks like a small wristwatch. When a patient wears an actigraph, all of his movements during sleep gets recorded. Some actigraph units also have the ability to measure light exposure. A doctor or a sleep specialist can analyze the data collected. There are also actigraphy that automatically transmit data to a computer. These units allow for real-time analysis.

Although it varies from one model to another, some actigraphy also have sensors. These sensors can monitor temperature, ambient light, parkinsonian tremor, skin resistance, sound levels, and a full data stream.

What is the connection between Delayed Sleep Phase Syndrome and Actigraphy?

Actigraphy is useful when diagnosing sleep disorders. Most of the time, combining actigraphy with the use of sleep diaries can yield a more accurate diagnosis. It can yield results as almost as accurate as of that of a polysomnogram. Actigraphy is useful in collecting data concerning the total sleep time. It can also tell the number of instances a person wakes up after getting to sleep.  However, actigraphy is not as good when evaluating sleep-onset latency times. This means that it may not be as effective when used in diagnosing a person with DSP.

The information on this website is not intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice. Read our full medical disclaimer.

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