What is Obstructive Sleep Apnea (OSA)

Good sleep is essential to ensure an efficient and effective performance of your daily activities. A normal adult requires an average of 8 hours of sleep per day. That is one third of our lifetime!


Sleep apnea is a condition characterized by multiple brief interruptions or cessation of breathing during sleep. It is increased with obesity and age and estimated to affect 5% of the adult population. The commonest form of obstructive sleep apnea (OSA).



Apnea can occur when excess tissue in the upper airway, such as abnormally large tonsils, blocks the airway during sleep. Apnea can also occur when the tongue or throat muscle relax too much leading to the collapse/closure of the upper airway.


  • Loud snoring
  • Cessation of breathing during sleep (apnea)
  • Choking, gasping, snorting during sleep
  • Restless sleep
  • Excessive daytime sleepiness (Epiworth Sleepiness Scale)
  • Morning headache
  • Dry mouth
  • Poor concentration and short term memory
  • Decreased libido


  • Hypertension
  • Stroke
  • Ischemic heart disease
  • Gastro esophageal reflux disease
  • Depression
  • Diabetes mellitus
  • Increased risk of motor vehicle accidents in drivers


  1. You need to undergo a physical examination and assessment by a physician
  2. You would then undergo an overnight sleep study (polysomnography [PSG]). This can be performed either at your home or at a hospital.
  3. The PSG would provide your doctor with details of your sleep pattern, breathing disturbances and blood oxygen level. Treatment will depend on the severity of the condition. Most patients will require the use of a Continuous Positive Airway Pressure (CPAP) machine during sleep to relieve the obstruction and symptoms.

The Epworth Sleepiness Scale is a simple way of accessing the degree of sleepiness. The higher the score (>10), the greater the likelihood of you suffering from sleep apnea.
0 = would never doze
1 = slight chance of dozing
2 = moderate chance of dozing
3 = high chance of dozing

Rate yourself in these situation. Chances of dozing from scale of 0-3

  1. Sitting & Reading
  2. Watching TV
  3. Sitting, inactive in public places
  4. As a passenger in a car for an hour without a break
  5. Lying down to rest in the afternoon when circumstances permit
  6. Sitting & talking to someone
  7. Sitting quietly after lunch without alcohol
  8. In a car, while stopping for a few minutes in the traffic

Note: Not all people with OSA experience daytime sleepiness. If you did not score in the higher ranges but you have concerns about your sleep, talk to our Specialist. Our Consultant Physician, Dr. Lau Wee Ming specialises in Sleep Study. She is available by appointment on Wednesday and Saturday. For more information, please call 603 – 6141 8533.