Last Updated on Apr 16, 2019

What is Polysomnography and Why is it Done?

Polysomnography, or sleep study is done to diagnose sleep disorders. It records your brain waves, breathing, heart rate, oxygen level in your blood as well as eye and leg movements during the study. It monitors the stages of sleep to identify if and during which stage sleep patterns are disturbed to arrive at a diagnosis based on the test findings.

Normally, the test measures sleep patterns during the night. However, polysomnography is sometimes done during the daytime to measure sleep patterns in workers who habitually work night shifts and sleep throughout the day.

The test is important since it is increasingly being recognized that lack of or disturbed sleep can cause several medical conditions such as heart disease, stroke and high blood pressure. Lack of sleep is associated with increased risk of injury, such as having a fall and road traffic accidents and poor concentration at work during the day.

A sleep study test will be recommended if your doctor suspects that you may be suffering from a sleep disorder such as -


  1. What Is Polysomnography? - (
  2. Polysomnography (sleep study) - (
  3. Kolla BP, Lam E, Olson E, Morgenthaler T. Patient Safety Incidents During Overnight Polysomnography: A Five-Year Observational Cohort Study. J Clin Sleep Med. 2013; 9(11): 1201-5. - (
  4. Narcolepsy - National Sleep Foundation - (

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