Sleep Apnea

Dr. LAM Bing

Director of HKSH Respiratory Medicine Centre

Specialist in Respiratory Medicine

A good sleep is about quantity and quality. If you want to feel refreshed and well throughout the day, the keys are to mininise the factors that affect your sleep and have good sleep hygiene.

Here are the 3 most important tips for better sleep:

1. Go to bed only when you feel sleepy.

2. Get off your bed or leave your bedroom if you cannot fall sleep after 15 minutes.

3. Do not go to bed for anything other than sleeping, e.g. using mobile phone, reading, eating, listening to radio, etc.

With the above 3 tips, a good sleeping habit will develop as the body learns to associate the bed with sleep. Other than lifestyles, some conditions may also affect sleep quality, especially sleep apnea. 

What is Sleep Apnea?

The whole body begins to relax when one falls asleep. The airway also narrows as the muscles of the respiratory tract relax. While it does not affect breathing of most people, the soft tissues of the throat or tongue may cause further narrowing or complete blockage of airway in sleep apnea patients, causing breathing difficulty and decreased blood oxygen levels.  

Breathing obstruction may go unnoticed by sleep apena patients, who may wake up and experience shortness of breath from time to time during sleep. Sleep apnea is diagnosed if one wakes up or is short of breath more than 5 times per hour during sleep. It is considered severe if more than 30 episodes occur per hour.

Long-term Impact of Sleep Apnea

Sleep apena patients are more prone to tiredness, poor memory and reduced concentration due to decreased rapid eye movement sleep.  Changes in blood oxygen levels may also lead to fluctuating blood pressure and speed up blood vessel deterioration, thereby increasing the risk of cardiovascular diseases such as hypertension, heart disease, stroke, etc.

With narrowed or obstructed airway, sleep apnea patients also tend to breathe more forcefully than normal. It can affect the esophageal sphincter and cause acid reflux.

High-risk Groups

Sleep apnea is more than severe snoring; it is also associated with a variety of health condition. The following are the risks for developing sleep apnea:

1. Obesity

Muscles begin to lose elasticity as fat accumulates, narrowing the respiratory tract.

2. Age

The respiratory tract also narrows with age as the muscles become less elastic, thereby increasing the risk of sleep apnea. 

3. Receding Chin

Besides genetic factors, children with nasal allergy are more likely to have an underdeveloped jaw as they breathe via the mouth. It increases the risk of sleep apnea.

4. Other Health Conditions

Hypertension, high blood cholesterol, diabetes, heart disease, stroke, carotid atherosclerosis, etc.

Examination and Treatment

Sleep apnea symptoms are mostly noted by family members or partners other than the patients themselves. For diagnosis, your doctor may prescribe a sleep standard test at home or in the hospital, during which a variety of wires are connected to your body and head for data collection and analysis. 

Your doctor will also choose the most suitable treatment for you based on the diagnosis. The use of positive pressure ventilation during sleep is currently the standard treatment for sleep apnea. It helps keep the airway open to prevent suffocation during sleep. Oral appliances are recommended for patients with receding chin and cannot tolerate the standard treatment, making the upper airway bigger.  For obesity-related sleep apnea, weight reduction can greatly improve the condition. 

Recently introduced in the US, hypoglossal nerve stimulation can improve the breathing of sleep apnea patients during sleep. Wires are implanted into hypoglossal nerves to enhance the elasticity of tongue and upper respiratory tract muscles by electrical stimulation, thereby keeping one’s airway open during sleep.  Research data suggests that the treatment can reduce the number of sleep apnea episodes from 30 to 5 or 6 per hour.

The long-term health effects of poor sleep cannot be underestimated. To regain a full and revigorating sleep, seek medical attention as soon as sleep apnea symptoms occur.