Sleep apnea is one of the most common sleep disorders arguably second to insomnia.
The World Health Organisation estimates that more than 100 million people have sleep apnea.
Another research reported that over 900 million adults globally have mild to severe obstructive sleep apnoea.
Here’s the thing: sleep apnea is rising fast. And the best way to fight it is to first know the common causes.
That’s exactly what we’ll do in this post – we will discuss the causes of sleep apnea.
Let’s get started.
What is sleep apnea?
Sleep apnea is a sleep disorder in which your breathing frequently stops and starts.
Why does your breathing stop repeatedly?
Two mechanisms contribute to the spontaneous breathing cessation related to sleep apnea. Let me explain.
Firstly, it is due to an obstruction of the airway, commonly known as Obstructive Sleep Apnea.
Secondly, the apneic episodes might stem from the brain, called Central Sleep Apnea.
Here, the quality and quantity of brain signals are not enough to support the breathing muscles during sleep.
Causes of sleep apnea
Let’s go ahead and look at some of the common causes of sleep apnea.
1. Excess weight
People who are obese are twice as likely to have sleep apnea compared to normal-weight adults. Here’s why.
Obesity causes excess regional fat accumulation. Some of the excess fat is usually deposited around the upper airways.
This can narrow the upper airways and restrict airflow.
But it gets even worse. Here’s why.
The deposited fat can exert a mechanical load on the upper airway structures.
This offsets the airway patency restricting airway flow primarily during sleep. And the fat deposited around the chest could impede the expansion of the lungs.
This leads to respiratory disturbances during sleep.
In one study, obese men with moderate to severe obstructive sleep apnea underwent an assisted weight loss program.
Results proved that an approximate weight loss of about 10 pounds led to a remarkable improvement in symptoms.
2. Oral and airway abnormalities
It is obvious that a narrow airway limits movement of air as compared to a much wider one.
In essence, people with such anatomical compromise are more likely to suffer from OSA. Airway abnormalities can reduce the diameter of the airway which would contribute to OSA.
Take for example this study from researchers at the University of Mississippi Medical Center.
They report that individuals with a short posterior mandible, a large tongue, and a large neck are at high risk of OSA.
Those with large tonsils and adenoids are also at high risk of developing OSA.
Several studies have revealed that children with enlarged tonsils suffer from OSA.
Moreover, further observational studies following the removal of their tonsils have shown substantial improvement.
3. Male gender
Population-based studies have shown a striking correlation between male gender and OSA.
Several reasons although poorly understood explain the frequent occurrence of OSA in males.
According to data from the Wisconsin Sleep Cohort Study, it was confirmed that OSA was more in men than in women.
The study shows that sleep-disordered breathing occurs in 24% of young-middle aged men and 9% of women.
In the older population, the difference was much smaller. 70% of older men and 56% of older women suffered from sleep-disordered breathing.
Other findings estimated the male-to-female ratio between 3:1 to 5:1 in the general population.
In some clinical populations, the recorded ratios of men to women were 8:1 to 10:1.
Still, other researchers argue that the reason for the lower prevalence in women is partly due to relatively more underdiagnosed female patients. Or rather misdiagnosis with depression or other illnesses in women.
Women are less likely to show the ‘classic’ symptoms or find it ‘unladylike’ to talk about their snoring.
Smoking is not only bad for your health, but it is linked to sleep apnea.
In one small cross-sectional study, researchers looked into the relationship between smoking and sleep apnea.
They found a smoking prevalence of 35% in patients with OSA compared with only 18% in those without OSA.
Now here comes the shocking part:
The study concluded that current smokers were found to be 2.5 times more likely to have OSA than former smokers and nonsmokers combined.
Turns out that nicotine which a substance present in cigarettes and tobacco impairs airway protective mechanisms.
For example research into the effects of passive smoke in animal models showed inhibitory effects on the airways’ protective mechanism.
Another study on humans suggests that smoking may not directly induce upper airways to collapse.
Instead, it magnifies the process by impeding the restoration of airway patency. Also, smoking irritates the upper airways
This triggers a gradual swelling process which can narrow the airways in the long run.
It’s worth noting that while the association between smoking and OSA is plausible, the evidence is less than conclusive.
As we grow older we become prone to more diseases. As such, sleep-related difficulties become increasingly common.
A study published by the American Thoracic Society(ATS) showed an increase in the prevalence of sleep apnea in men with increasing aging.
Here’s what they found:
- In men 20 – 44 years old the prevalence was 3.2%
- The prevalence almost quadrupled in the age range of 45 – 64 years to around 11.3%
- In men 61 – 100 years old the prevalence was 18.1%
Researchers concluded that the upper airways weaken as one age.
Aging is associated with increased upper airway resistance and decreased pharyngeal size.
In a study, a group of 55 patients aged over 65 yrs was observed. Another younger group of 50 patients was collected in a controlled group.
Results obtained showed a higher incidence of airway collapse in the older group. Also, fat deposition around the pharynx increases with age.
6. Cardiovascular disorders
Symptoms of sleep apnea could be due to an underlying cardiovascular disorder.
Studies show that heart failure, hypertension other heart-related disorders cause sleep apnea.
When the pump function of the left heart is impaired the lungs are overloaded with blood. This condition impairs respiration.
One research assessed patients with mild forms of heart failure. Turns out that 53% of the patients had sleep-disordered breathing.
Also, 38% had central sleep apnoea (CSA) and 15% had obstructive sleep apnoea(OSA)
Another study involving 400 patients with sleep apnea showed that 48% of them had heart rhythm disorders.
7. Use of alcohol
Are you consuming too much alcohol? Then is time to cut down on it since it’s one of the causes of sleep apnea.
Moderate consumption of alcohol has proven to be beneficial.
But for most people, it is difficult to stick with the designated limits of what constitutes moderate drinking.
Various analyses and studies suggest that a history of alcohol consumption is common among people with OSA.
Alcohol is thought to reduce respiratory muscle tone. This predisposes one to upper airway collapse.
Also, excessive alcohol intake contributes to dietary intake and an increase in body mass index.
One research showed that the percentages of OSA in current and past alcohol consumers were higher than non-consumers.
Further analyses suggest that reducing alcohol intake is of potential therapeutic and prevent value.
Sleep apnea is a serious medical condition that can affect anyone at any age, even children.
The majority of individuals with sleep apnea are often unaware of their sleep disorder. They are thus undiagnosed and untreated.
If you have sleep apnea, there are a few signs. Sometimes you have excessive daytime sleepiness and fatigue. Others might experience morning headache, irritability, nocturia, and memory loss.
Obesity, alcohol consumption, and smoking greatly increase the risk of sleep apnea.
As such lifestyle modification remains one of the main ways to fight it.