Polysomnography is a sleep study used to diagnose sleep disorders. During the test, several body functions are recorded. After the test, the doctor can treat any issues that arise based on the results.

If you want to learn more about how to treat sleep disorders, click on the link provided here.

In this article, you'll learn about what the polysomnography test is and why it's done.

(Read More - Circadian Rhythm Sleep Disorder)

  1. What is a polysomnography test?
  2. Why is a polysomnography test done?
  3. Risk of polysomnography test
  4. Polysomnography test results
  5. Takeaway
Doctors for Polysomnography test : What it is, Why is it done, Risk and Result

A polysomnography test is a sleep study used to investigate sleep disorders. It records brain waves, oxygen levels in the blood, heart rate and breathing, as well as eye and leg movements. Polysomnography tests are usually conducted at a sleep center or unit in a hospital, typically during the night. Along with detecting sleep disorders, the test can also help adjust treatment for existing sleep disorders.

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A polysomnography test monitors the different stages and cycles of sleep. It mainly records breathing rate, airflow, oxygen levels, and heart rate. Polysomnography tests are generally conducted in the following situations -

Sleep apnea or other sleep-related breathing disorders

This occurs when a person's breathing repeatedly stops and starts during sleep. People with this disorder may snore loudly and wake up frequently.

(Read More - Central Sleep Apnea)

Periodic limb movement disorder

This disorder involves repetitive bending and stretching of the legs during sleep. It's often associated with restless leg syndrome.

(Read More - Obstructive Sleep Apnea)


This is a condition characterized by excessive drowsiness and sudden sleepiness during the day.

(Read More - Delayed Sleep-Wake Phase Syndrome)

REM sleep behavior disorder

This disorder involves abnormal behavior during the rapid eye movement (REM) stage of sleep when people are dreaming. It can cause people to act out their dreams while they are still asleep.

(Read More - How to Go to Bed Early)

Strange behavior during sleep

If a person walks or has rhythmic movements while sleeping, the doctor may recommend a polysomnography test.

(Read More - Complex Sleep Apnea Syndrome)

Chronic insomnia without cause

If someone has difficulty sleeping or sleeps excessively, they may be asked to undergo a polysomnography test.

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A polysomnography test is considered to be a risk-free test as it does not cause any pain. However, during the test, electrodes are placed on the skin, which may cause a slight burning sensation. No other risks have been identified for the test.

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It usually takes around 3 days to receive the results of a polysomnography test. The results may indicate the following types of sleep disorders -

  • Sleep apnea or other breathing disorders
  • Seizure disorder
  • Periodic limb movement disorder or other movement disorder
  • Narcolepsy or unusual daytime tiredness

To identify sleep apnea, the doctor may review the polysomnography test report in the following ways -

  • Checking the frequency of apnea, which occurs when breathing stops for 10 seconds or more.
  • Checking the frequency of hypopnea, which occurs when breathing is shallow for 10 seconds or more.

After reviewing these results, the doctor can check the Apnea Hypopnea Index (AHI) score. An AHI score of less than 5 is considered normal. This, combined with normal brain waves and muscle movement data, suggests that the patient does not have sleep apnea. However, an AHI score of 5 or more is considered abnormal. The chart below shows the different levels of sleep apnea severity based on AHI score -

  • AHI score of 5 to 15: Mild sleep apnea
  • AHI score of 15 to 30: Moderate sleep apnea
  • AHI score greater than 30: Severe sleep apnea

(Read More - Not Able to Sleep at Night What to Do)

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The polysomnography test is done at bedtime. At this time the doctor records the sleep pattern and it is ascertained whether there is any sleep disorder. Polysomnography test is done in conditions like sleep apnea and REM sleep behavior disorder.

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Dr. Vinayak Jatale

Dr. Vinayak Jatale

3 Years of Experience

Dr. Sameer Arora

Dr. Sameer Arora

10 Years of Experience

Dr. Khursheed Kazmi

Dr. Khursheed Kazmi

10 Years of Experience

Dr. Muthukani S

Dr. Muthukani S

4 Years of Experience

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