what is sleep apnea explanation pause of breathing during sleep

What is Sleep Apnea?

apnea notturna: cos'è?

Sleep apnea, also known as sleep apnoea, is an involuntary pause of breathing during sleep. Yes, you read it right! An apnea occurs when a person stops breathing for 10 seconds or more(1). This may recur up to hundreds of times during the night.

One of the major difficulties with sleep apnea is that 80% of people are unaware that they suffer from it, and therefore remain untreated(4).

This pathology has to be taken very seriously as sleep apnea can strike people of all ages, even children.


Sleep apnea or Hypopnea?

Obstructive Sleep Apnea (OSA) is the most common type of sleep apnea(2). It is caused by an obstruction of the airway in the throat(1). It affects people of all ages, and 1 to 6% of the world adult population(2).

Hypopnea is a breathing disorder which involves episodes of shallow breathing or an abnormally low respiratory rate for an extended period of time. It can cause a 3% or greater drop in oxygen in the blood(1). The hypopnea implies a partial obstruction in the airway, whereas in apnea the obstruction is complete.


You are not alone!

1 to 6% of adults are affected by sleep apnea(2).
77% of obese people suffer from sleep apnea(3).
80% of people are unaware that they suffer from OSA, and therefore remain untreated(4).

Why do you suffer from sleep apnea?

Some factors predispose to have this disorder. These risk factors include but are not limited to being male, overweight, over the age of 50, having a large neck size, a narrow nose, a small jaw bone or having a family history of sleep apnea(5).


What is the mechanism of sleep apnea?(5)

While you are awake, the muscles of your throat and the back of your tongue are active and the air flows easily. But during sleep, the muscle tone decreases. Your airway may be blocked or narrowed simply because your throat muscles tend to relax more than normal. The soft tissues in the rear of the throat collapse and so your breathing may be blocked or obstructed.

As airflow stops, the oxygen level in your blood drops. Your brain will notice this lack of oxygen and will respond by disturbing your sleep with awakenings. This may occur several times during the night. As a result, the patient's sleep is extremely fragmented and of poor quality.

If you have obstructive sleep apnea, you probably won’t remember these awakenings because you were not in a conscious state of mind at they occured.


What is it like to live with sleep apnea?

If you suffer from sleep apnea, you generally have no problem to fall asleep but your night is not restful although you may not notice. Sleep apnea can affect your quality of life and health. Prior to diagnosis, OSA is associated with a large number of tedious symptoms(5). You can feel tired in the morning or tend to doze off in the daytime(5).

Sleep apnea is always associated with snoring, but not everyone who snores necessarily suffer from this breathing disorder(5).


You may have some other symptoms(5) such as:

  • Frequent nightmares,
  • Repeated trips to the toilet during the night,
  • Feel stifled while sleeping,
  • Waking up with a headache,
  • Irritability,
  • Reduced libido,
  • Cardiac or vascular problems,
  • Daytime sleepiness…


When do we speak of sleep apnea?

Sleep apnea is a very common pathology, but the lack of awareness means the majority of patients remain undiagnosed and therefore, untreated.


Left untreated, sleep apnea can have serious and life-shortening consequences. Only a sleep study can show definitively if sleep apnea is present and how severe it is.

The doctor will confirm the diagnosis by tests, measuring your apnea-hypopnea index AHI=(Number of apnea episodes + Number of hypopnea episodes per hours of sleep), knowing that a AHI > 5/Hours is a sign of sleep apnea.



(1) Rules for Scoring Respiratory Events in Sleep: Update of the 2007 AASM Manual for Scoring of Sleep and Associated Events – Journal of Clinical Sleep Medicine, Vol. 8, No. 5, 2012

(2) The World Health Organization. Chronic respiratory diseases www.who.int/gard/publications/chronic_respiratory_diseases.pdf viewed 05/21/2015

(3) Evidence supporting routine Polysomnography before bariatric surgery – O’Kefee et al – Obesity Surgery - January 2004

(4) Obstructive Sleep Apnea – A guide for GP’s – British Lung Foundation (NHS)

(5) Sleep breathing disorders – European Respiratory Society WhiteBook (chapter 23)

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