Obstructive Sleep Apnoea (OSA)
Obstructive Sleep Apnoea is defined as the coexistence of excessive daytime sleepiness with irregular breathing at night. It occurs in 1-2% of men and around 0.5% of women.
In affected individuals, during sleep there is a partial or complete collapse of airways resulting in stoppage of breathing, with a consequent drop in oxygen levels in the blood. These individuals are woken up by the brain which is sensing the low oxygen levels and a few deep breaths are taken, restoring the oxygen. Sleep is resumed, the airway collapses and the cycle is repeated, often hundreds of times during the night. The patient therefore awakes feeling unrefreshed and suffers with excessive daytime sleepiness.
Factors affecting this condition include a small jaw, large tonsils, increased soft tissue around the neck (obesity), older age, alcohol, sedatives, and previous strokes causing a floppy airway.
Patients can seek help from their doctor due to problems with high blood pressure, loss of memory, altered mood and personality, relationship strain, or breathlessness, when the underlying problem may be OSA. Road traffic accidents are also more common in OSA patients, as they fall asleep at the wheel.
The characteristic symptoms of OSA are excessive daytime sleepiness, snoring and mood changes. Also noticed are stoppages of breathing during sleep witnessed by the partner, choking sensations during sleep, waking up often to pass urine, poor concentration, decreased libido, and morning headaches.
Prognosis is good with treatment; patients will have a normal life expectancy. Without it however they can develop respiratory failure. Heart failure and rhythm disturbances are thought to be long-term effects of untreated OSA.