“As if my husband is cutting down a forest.” ‘Because of all that snoring I went to lie in another room.’ “Sometimes I wake up and he’s not breathing – terrifying.” Sometimes it is not people with sleep apnea but their partners who are the first to sound the alarm, says Peter van Maanen, ENT specialist and somnologist at the OLVG hospital in Amsterdam. “Not every patient immediately realizes that something is wrong.”
Sleep apnea: It is a medical condition that has been in the news a lot in the past year. The CPAP devices from Philips were almost always the reason. These ensure that apnea patients receive a continuous positive airway pressure are administered, a continuous flow of air that facilitates breathing during sleep. But in 2021, the company publicly announced that some of its sleep apnea devices could release chemicals that are potentially carcinogenic. Philips is now replacing and repairing devices and a lawsuit is pending in which Dutch patients are demanding that the Ministry of Health, Welfare and Sport provide access to confidential correspondence about the devices.
Read about the lawsuit: Six hundred users of Philips apnea devices are going to court
What is Sleep Apnea? What causes it, how do you recognize it, and are there other ways to manage the symptoms other than CPAP?
“Apnea is the medical term for respiratory arrest,” says Van Maanen, who obtained his PhD on position-dependent sleep apnea. The word comes from Greek and means ‘no air’. “Such a breathing stop is nothing unusual, we all have that sometimes, sometimes several times a night. Especially when people lie on their backs, there is a good chance that their breath will stop for a while, because soft tissue can then close the throat under the influence of gravity, among other things. The muscle tension of the tongue and soft palate decreases during sleep and these tissues can fall backwards.”
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Heart rate and muscle tension
When that happens, breathing can stop completely for a while, or there is a greatly reduced airflow. In the latter case, there is a hypopnea. “In both situations, the oxygen concentration in the blood can drop, after which the heart rate and muscle tension in the airways increase, so that breathing can start again. You can wake up to that, but you don’t have to.” The breathing stops are often accompanied by snoring, but not every snorer is immediately apnea patient.
Only when such breathing stops occur at least five times per hour is there obstructive sleep apnea (OSA). When talking about sleep apnea, that is often what is referred to. The American Academy of Sleep Medicine uses a method (also used by the OLVG) to measure apneas that looks at the percentage of ‘flow reduction’ in the airways per ten seconds. This is measured with a meter in the nose and electrodes on the body.
In addition to OSA, there is a rarer form, CSA: central sleep apnea. There is no obstruction (and usually no snoring), but there is something wrong with the control from the brain. The brain simply does not provide enough stimuli to breathe. This usually occurs in people with brain disorders, such as Parkinson’s disease, or in people who have had a stroke or chronic heart problems.
As fresh as a daisy
According to figures from the Apnea Association, about 600,000 people in the Netherlands probably have a serious form of sleep apnea (mainly OSA), less than half of whom are being treated. Nevertheless, Van Maanen is reluctant to mention specific numbers. “Precisely because not everyone suffers from it to the same degree. As mentioned, breathing stops are not abnormal, and if you happen to have six per hour but you are as fresh as a fiddle during the day and neither your health nor your relationship suffers, then there is basically no cause for concern. But if you are excessively sleepy during the day or have heart problems, then it is a reason to do something about it.” With more severe forms of OSA and complaints of excessive daytime sleepiness, people can even fall asleep while driving.
There are also apnea patients who have to urinate remarkably often at night
Peter Van Maanen arts
The fact that people with sleep apnea can be so sleepy during the day is partly because their brain briefly goes into wakefulness with every pause in breathing: even if they are not immediately aware of this, their sleep is interrupted. Van Maanen: “This fragmented sleep at night leads to reduced sleep quality and increased sleep pressure during the day. Some actually startle awake at night, with or without a feeling of being stuffy. And there are also apnea patients who have to urinate remarkably often at night. One theory is that the breathing stops cause an increased secretion of so-called natriuretic peptides in the heart, which in turn leads to an urge to urinate.”
If severe apnea is left untreated, it can entail major health risks, Van Maanen emphasizes. “A high number of breathing stops and oxygen pressure drops increase the risk of heart and cerebral infarctions, high blood pressure and atrial fibrillation, among other things. If people also suffer from insomnia, i.e. insomnia, the risk is even higher.”
Less violent forms
The treatment of sleep apnea depends first of all on the variant. OSA can be position dependent and only occur in the supine position, just like the ‘regular’ apneas that people sometimes have. Van Maanen: “We see position dependency more often, especially in people with less severe forms of sleep apnea. During my PhD I researched the effect of a band that is placed around the chest and that vibrates when you lie on your back. The idea is that as a result, you automatically turn onto your side in your sleep.” That is an easy treatment, but patient forums show that the belt does not work for everyone: some people wake up from the vibration or do not react to it, others shift the belt in their sleep in such a way that they can continue to sleep undisturbed on their back. Scientists still know too little about the influence of, for example, a soft or hard mattress on sleep apnea.
“If someone comes by with apnea complaints, I always try to ask about lifestyle. If someone drinks ten glasses of alcohol a day or if someone is seriously overweight, it is my job as a doctor to point out the health risks of this. Lifestyle changes can sometimes go a long way. Traditionally, OSA has been a disease of middle-aged, overweight men. And although we are also seeing more and more women these days, being overweight is still true.” Not only are overweight people more likely to develop OSA, the reverse is also the case: people with OSA are more likely to become obese. “This is because there is a disruption in their endocrine system, as a result of which substances that stimulate appetite and regulate the feeling of hunger are secreted in the blood in different concentrations.”
Surgical procedures or mouthguard
CPAP is still the usual advice for more severe forms of apnea, he emphasizes. “Both with obstructive apnea and with central apnea, although the airflow pressure is usually lower in the latter case.” Only if that does not work, other solutions are considered in the case of OSA – for example, a mouthguard that moves the lower jaw slightly forward, or surgical intervention.
There are also treatments that target specific nerves. For example, an international team of ENT doctors, including Van Maanen’s colleague Nico de Vries, published a study in 2014 in the New England Journal of Medicine to so-called tongue nerve stimulation. “You use a pacemaker to provide electrical stimulation to the hypoglossal nerve, a motor cranial nerve whose function is to move the tongue forward. Since 2014, 40,000 people worldwide have had this type of surgery. It is a more expensive treatment for which only patients with severe apnea who have failed CPAP treatment are eligible.”
Finally, there is a new treatment for patients with CSA that revolves around stimulation of the phrenic nerve, or phrenic nerve. This stimulates the diaphragm via a pacemaker to achieve more normal nighttime breathing.
“At the moment it is not yet being carried out in the Netherlands,” says Van Maanen. “But next year we will start with the first tests. We are always learning in the field of sleep apnea treatment.”