You may have heard of a test called ‘sleep study’ or ‘polysomnography’. What is it? Can sleep also have diseases? How is a sleep study test done?

Sleep is characterized by its own set of medical problems and disorders, which are among the most common affecting human beings. Snoring is a common phenomenon and almost every family has a person who snores loudly while sleeping. However, it is not generally known that snoring accompanied by breathing difficulty may be due to a sleep disorder called obstructive sleep apnoea (OSA).


OSA is a disease of the wind pipe, especially the upper part. Due to old age, obesity, alcohol consumption, smoking, etc. the upper wind pipe gets loose and flabby instead of rigid and tight. During day time it remains open and functions normally. However, during the night time, it collapses and closes, leading to obstruction or blockage to air-flow.

Due to this blockage, there might be problems like choking, low oxygen levels, etc. It is important to note that initially this blockage is not permanent. So, the windpipe spontaneously opens and closes all through the night. Whenever it closes it causes problems.

Whenever there is a block the oxygen delivery to the lungs and body will reduce. This leads to a host of problems in the body like low oxygen levels, stress on the heart and brain, frequent awakening from sleep,etc. Over time, it can lead to weight gain,diabetes, hypertension, heart attacks, strokes or paralysis, etc.

OSA is an important cause of sleepiness during the day, mental dullness, frequent episodes of closing eyes while working or driving, which may sometimes result in accidents.  A common complaint of these patients is that they never feel rested, despite sleeping for over 10 hours a day!


Sleep disorders such as OSA are diagnosed by sleep studies. During a full-fledged sleep study, patients are required to stay overnight in the hospital. Their sleep pattern is analysed with the help of the polysomnograph, which measures multiple parameters such as brain wave patterns, breathing patterns, abdominal wall movements, heart rate, etc. All these parameters are recorded and then reviewed and analysed. Depending upon the report, the patient may have to stay another night for the application and titration of the appropriate treatment.


Besides sleep-hygiene measures, the treatment of OSA essentially requires the regular use of continuous positive airway pressure (CPAP) during sleep which is administered with the help of a CPAP/BiPAP machine and a tight-fitting face mask. Use of this machine reverses the blockage of the windpipe and improves sleep quality and other parameters.