Sleep apnea (also spelled sleep apnoea) is a sleep-related disorder characterized by abnormal breathing patterns during sleep. People with sleep apnea have reductions or pauses in breathing for brief periods during sleep. While this may cause a person to awaken periodically and reduce sleep quality, the sleeper may not fully wake up and remain unaware that their nighttime breathing is abnormal. Several type of sleep apnea exist, categorized by the cause of breathing disruption. The most common is "obstructive sleep apnea" (OSA), in which the upper airway is obstructed due to loss of tone in the pharyngeal musculature. OSA can be defined as the presence of five or more obstructive events (either apnoeas or hypopnoeas) per hour of sleep.
Obstruction of the airways causes the sleeper to wake up (usually not fully) and take several deep breaths. As this happens frequently (many times per hour), it reduces sleep quality and may have some (or all) of the following effects on the person:
- Snoring (due to taking deep breaths and the obstructed airways)
- Feeling tired during the day, sleepiness
- Headaches, especially after wake up
- Difficult concentration
- Mood swings
Note that while all of the above effects may indicate that a person is suffering from OSA, none of them are definitive and dedicated tests are necessary for reliable diagnosis.
- Hypothyroidism (low levels of the thyroid hormone which controls metabolism)
- Family history
OSA is also associated with an increased risk of coronary artery disease, hypertension and stroke although there is some debate as to whether the association is causal or secondary to associated obesity, which is often present.
OSA is diagnosed by a performing a sleep study. This can be done at home or through an overnight stay in a specialized sleep laboratory.
Diagonosed, suspected or unsatisfactorily treated OSA may lead to a pilot or air traffic controller being assessed as temporarily unfit. Return to flying/provision of service is normally allowed after successful treatment, demonstrated by reduced daytime sleepiness and absence of snoring.
Sleep apnoea can sometimes be treated by making lifestyle changes like losing weight, giving up smoking and reducing how much alcohol a person drinks.
In some cases, the use of a specially shaped pillow or shirt may reduce sleep apnea episodes, usually by causing users to sleep on the side instead of on the back or in a reclining position instead of flat.
Continuous positive airway pressure (CPAP) is a dedicated solution for OSA treatment. This is a device that keeps the patient’s airway open during sleep by means of a flow of pressurized air into the throat. The CPAP mask is similar to the cockpit oxygen mask and the devices are light-weight and quiet. Therefore, CPAP is the most commonly used treatment for sleep apnea. This treatment is extremely effective for those who tolerate it (most people do). Unless major weight loss occurs, CPAP treatment is likely to be needed lifelong.
Another option is to use oral appliance therapy (OAT) (also called mandibular advancement device, MAD), which is a custom-made mouthpiece that shifts the lower jaw forward thus opening up the airway.
In some cases surgery (e.g. removing large tonsils) can be helpful.