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Sleep Health

Snoring & Sleep Apnea – How Does Sleep Apnea Occur?

Did you know that Snoring and Obstructive Sleep Apnea (OSA) are intrinsically linked? People with Sleep Apnea snore really loudly and regularly, and it is a potentially serious medical condition (1).

OSA is clinically referred to as a chronic sleeping disorder. This is characterised by loud habitual snoring and repeated stop breathing spells (2). And, those stop breathing spells can happen literally over a hundred times per hour in the course of the night.

How common is sleep apnea?

It is very common.

“It is estimated that up to 13% of men and up to 4% of women have obstructive sleep apnea in Australia.”

According to the Sleep Health Foundation, one in five Australians is estimated to be affected by a major sleep disorder. These include OSA, insomnia, Restless Legs Syndrome, circadian rhythm disorders and central disorders of hypersomnolence (3).

Who is affected by sleep apnea?

OSA can happen at any age. In children, OSA is often the result of enlarged tonsils or adenoids and its occurrence increases with age. In a 2016 Sleep Health Foundation National Survey, it was highlighted that 5% of 18 to 24-year-olds have been diagnosed with OSA compared to 12% of people over 65 years of age (4). In other words, OSA is more common in middle-aged and older people. It is also more common in men than in women, although after menopause, the risk becomes similar.

So how does Obstructive Sleep Apnea occur?

Blocked Airway passages

Understanding how snoring and sleep-disordered breathing (SDB) changes the airway through the throat (also known as the “upper airway” or ‘’pharynx’’), gives you a greater understanding of how OSA can occur.

If someone has SDB, the amount of limited airflow experienced with or without snoring varies continuously throughout the night. As the upper airway muscles start to relax, the suction effect of each inward breath tends to draw the soft tissues down towards the back of the airway. Over a series of breath’s, the airways progressively narrow and the airflow decreases. There are times when airflow stops completely because the airway is blocked. As a result, breathing is stopped!

What is the meaning of Apnea?

The word “apnea” literally means “without breath” (5). An apnea is defined as a complete cessation of breathing that lasts up to 10 seconds, and in severe cases, even up to 60 seconds (1 minute) or longer. It is where the airway becomes fully blocked, obstructing oxygen from reaching the lungs. This may happen a few times a night or several hundred times a night in more severe cases.  During this time, heart rate will drop significantly, as does the oxygen level in the blood, since no fresh air enters the lungs to replenish the depleted oxygen. The brain soon realises that the body is struggling. That is why an apnea always triggers a strong arousal with severe effects on the body.

With every arousal, the person may move to a different position in the bed, but will probably not remember waking up, even if arousals occur hundreds of times each night. The bed partner is likely to notice the apneas and arousals, mainly because together with snoring, they keep him or her awake, and as a result, they too have a restless sleep!

Lady covering her ears whilst her partner snores

The Body’s Stresses

When the strong arousal occurs, so does gasping for air, choking and loud noise effects. Arousals jolt the cardiovascular system. Brain activity increases significantly. The heart rate after arousal is almost double what it was during the apnea. There is a rapid increase in airflow, and the blood oxygen level will begin to rise again. The tongue and soft palate, quickly return to their normal position, as the airway opens fully.

Flow Arousal

“Apnea arousal cycles product significant stresses to the body and has significant health consequences.”

Apneas cause a fall in oxygen supplies to the body’s vital organs, including the brain. There is also an increase in carbon dioxide.

If you have severe Sleep Disordered Breathing such as OSA, you will have poor quality sleep. You may rarely experience the normal sequence of light and deep sleep stages which are necessary for healthy sleep.

Take our interactive online quiz to ascertain your risks for sleep apnea.