Common Conditions

Snoring and Sleep Apnea


Snoring, often the butt of party jokes, is no laughing matter. It may be the first sign (or sound) of a potentially life-threatening disorder known as obstructive sleep apnea. Loud snoring and obstructive sleep apnea (OSA) are manisfestations of sleep induced narrowing of the upper airway causing breathing problem (sleep disordered breathing) which may affect the quality of your sleep, health and quality of your life. It is a common but often under-recognised condition. One large study in USA noted a prevalence of sleep disordered breathing of 9-24% in men and 4 – 9% in women.

What is Obstructive Sleep Apnea?

People with OSA experience repeated obstruction to breathing during sleep due to a narrowing or collapse of the upper airways (the air passage behind the tongue and above the vocal chords) (figure 1..). This collapse occurs due to excessive relaxation of the upper airway muscles during sleep, leading to temporary disruption of breathing and resulting in a fall in the oxygenation of the blood. The person (still asleep) is often observed by the bed-partner struggling to breathe until these efforts ‘arouse’ his brain which results in stiffening of the upper airway muscles and re-opening of the collapsed airway. Breathing resumes with gasping breaths and loud snoring. People with OSA have a characteristic pattern of snoring; intermittent loud snorts interspersed with periods of silence during the obstruction. Such episodes of stoppage of breathing (apnea) can occur hundreds of times each night, causing disruption to breathing and sleep. The blood pressure rises during apneas as well as changes in heart rate and rhythm. Sleep, therefore, becomes a ‘stressful’ activity to these patients, in contrast in a normal person when sleep is genuine rest.

What are the symptoms and complications of OSA?

Common symptoms

  • Daytime sleepiness and tiredness
  • The repeated arousals from sleep to resume breathing causes sleep fragmentation and poor quality sleep. Over time patients will complain of increasing daytime sleepiness which can be very disabling
  • Loud snoring
  • The bed partner suffers together with the patient because of the unbearable loud snoring repeatedly punctuated by periods of silence and gasping breaths

Less common symptoms

  • Dry mouth upon waking up in the morning
  • Morning headaches or heaviness in the head
  • Feeling unrefreshed upon waking up despite a ‘good’ night’s sleep
  • Frequent urination at night (nocturia)
  • Excessive sweating during sleep
  • Short term memory lost
  • Irritability
  • Sexual dysfunction (impotency)

Health Consequences of OSA

  • If left untreated, OSA can affect the well being of a person and is a potentially life-threatening illness. Daytime sleepiness can be so severe that patients may fall asleep inappropriately e.g. while driving, during an important meeting or during casual conversation. In fact, OSA patients are 7 times more prone to encounter vehicular accidents compared to the general population
  • The repeated dips in oxygenation during the apnoeas may over time be a contributory risk factor to developing high blood pressure, heart disease, stroke and even depression
  • More than 35% of OSA patients suffer from high blood pressure
  • 60% of stroke patients have sleep apnoea

How is OSA diagnosed?

If you are a loud habitual snorer, have choking episodes during sleep (observed by bed partner) and suffers from daytime sleepiness or tiredness, chances are you have OSA. You can also answer a simple questionnaire (Epworth Sleepiness Scale) to assess whether you are likely to have OSA based on the degree of daytime sleepiness. You should see a sleep specialist. The doctor will obtain a detailed medical history and physical examination. If OSA is suspected, a diagnostic sleep study (polysomnography) will be carried out. This can be done in a sleep centre in hospital or in the convenience of your own home. Breathing, blood oxygenation level, snoring, brain activity and many other parameters are monitored. The sleep study will enable the doctor to diagnose and assess the severity of the condition.

How is sleep apnea treated?

The basic objective of treating OSA and reversing all the complications is to prevent the upper airway from collapsing inwards during sleep. The various options available include:

  • Continuous positive airway pressure (CPAP) therapy
  • Upper airway surgery
  • Oral appliances
  • Lifestyles modifications

Continuous positive airway pressure (CPAP)

  • The commonest and most effective non-invasive therapy prescribed for OSA is CPAP. The patient wears a small soft nasal mask over his nose and the machine delivers air pressure through a tube connected to the mask. The pressure acts as an “air splint” which prevents the upper airway from collapsing during sleep. Breathing is normalised and the patient can now breath and sleep normally like a normal person. CPAP is well established and is very effective as it can dramatically reduce the daytime sleepiness and tiredness after a few nights of usage
  • CPAP machines
    • It is important to find a proper fitting and ‘comfortable’ mask. Masks comes in various types & sizes (nasal pillows, nasal mask, full face mask). Your sleep specialists will be able to help select the right mask and machine. Newer CPAP machines are automatic i.e. the machines will automatically adjust the necessary air pressure to prevent the apneas and also is able to record the pressures and important information in a memory chip. Your sleep specialist may download the data for review to ensure you are using the machine effectively. In Singapore, CPAP machines like Breas, ResMed and Respironics are all available for trials. Your sleep specialist will prescribe the right mask and machine suitable for you
  • Upper airway surgery
    • The principle of surgery is to create a bigger, stiffer and more stable upper airway so that it will not ‘collapse’ inwards during sleep. Various surgical procedures are available and these usually involve removal of redundant tissues in the upper airway. Such procedures include:
      • Uvulopalatopharyngoplasty (UPPP)
      • Laser assisted uvuloplasty (LAUP)
      • Somnoplasty (Radio frequency procedure)
      • Genioglossus (tongue) advancement
      • Tracheostomy
    • Success rate for these procedures varies according to the expertise of the surgeons and the proper selection of patients and this may vary from 50 – 70%. As such, surgery is not often offered as the first line of treatment
  • Oral appliances
    • These are custom made dental appliances that patients wear to sleep and they work by bringing the lower jaw forward thus enlarging the upper airway. These devices are sometime useful in patients with loud snoring and mild OSA
  • Lifestyle changes
    • People with OSA are often overweight. Partial weight loss (about 10%) may improve the condition
    • Alcohol consumption at night worsens OSA because the sedative effect depresses breathing further making the apnoeas more frequent and longer. Therefore avoidance of alcohol is important
    • Avoid sedative drugs. Like alcohol drugs that sedates will further depress breathing

The doctors in Singapore Respiratory Specialists will be able to help you with the right assessment and treatment if you think you have obstructive sleep apnoea syndrome.

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[Article Ref: Singapore Respiratory Specialists (SRS)]