The human being breathes continuously, in a semi-automatic way, during all his life. Breathing allows us to obtain the oxygen that our cells need to survive, and the absence of this process for long enough causes us to die (in fact, for a long time the moment when we stop breathing was considered to be the moment of death). This is so essential that it is necessary even when our level of consciousness is altered, and even when we sleep.

But sometimes during sleep some alterations are produced that make it difficult for us to carry out this vital process, even for a few seconds. Thus, we may encounter different respiratory disorders during sleep . We will talk about this type of health alterations in this article.

Breathing disorders during sleep

Breathing disorders of sleep are understood to be those alterations that occur during the period of sleep in which insufficient ventilation or breathing or a change in the breathing rhythm occurs. Mostly, these are disorders in which apneas appear, or brief periods in which the patient stops breathing for at least ten seconds and which usually generate a partial awakening of the subject to be able to inhale and receive oxygen. There is also another associated concept, hypoapnea, in which although the subject does not stop breathing at any time, the amount of air that enters the body is greatly reduced when the breathing becomes more superficial.

These disorders tend to generate frequent (mostly unconsciously perceived) nocturnal awakenings , and are often linked to the occurrence of snoring. They usually have consequences, being perhaps more visible is the difficulty in maintaining a continuous and repairing sleep, which may result in the appearance of daytime drowsiness, fatigue and difficulties in concentration. It can also lead to problems at the relational level, such as discomfort and conflicts with bedfellows.

Breathing disorders during sleep are seen by the majority of the population as something mild that does not generate complications, and in some cases this is true, but in reality the presence of a breathing disorder during sleep can have a series of serious health consequences if it is not treated correctly.

They can have very harmful effects on our cardiovascular system: in fact, this type of disorder is a risk factor for heart disease. Obstructed airflow leads to pulmonary hypertension and an overloaded right ventricle (the part of the heart that sends blood to the lungs for re-oxygenation), which can lead to a higher likelihood of arrhythmias, angina pectoris and even heart attacks.

It can also have cognitive effects, since it makes it difficult to maintain and rhythmize sleep cycles and, in addition, the presence of repeated micro-anoxies can lead to the death of groups of neurons . In children, it can also lead to growth and developmental delays, as well as increased insulin resistance or other metabolic problems. They have also been found to be detrimental to patients with diabetes and neuromuscular disorders.

Types

There are many different phenomena that could be considered as sleep breathing disorders and that have different levels of impact on the subject who suffers them. Below are some of the most common.

1. Obstructive Sleep Apnea

Perhaps the best known sleep disorder, obstructive apnea is a disorder in which the sufferer suffers during sleep the obstruction of the upper airway, despite continuing to perform the action of breathing . This causes the breathing rhythm to increase in an attempt to receive the air that does not arrive.

Non-conscious awakenings and micro-wakenings are frequent during sleep, although the subject ends up waking up to the contraction of the muscles linked to breathing, in search of oxygen. This may occur cyclically several times during the night.

One of the most frequent symptoms is the presence of irregular and high intensity snoring, in addition to the awakening caused by our organism’s search for air. It is not uncommon for vivid dreams and high levels of night sweating to appear. During the day they often suffer from fatigue, lack of strength, memory problems and reduced sexual appetite. Arrhythmias are common and can lead to severe heart problems.

2. Central Sleep Apnea

Central sleep apneas are those types of apneas that occur when a person’s airway is not obstructed but allows air to pass properly, yet there is a decrease in airflow. The problem itself is that the body does not make the effort to breathe normally. In other words, there is an interruption in the flow of air due to a reduction or absence of breathing effort.

This is a problem derived from a heart or brain disorder, and there are many possible causes. Unlike other apneas and sleep disorders, snoring is not common and may even go undetected. What is perceived is the presence of daytime fatigue, nighttime awakenings caused by the sensation of suffocation and sometimes fear of sleep due to these sensations.

3. Mixed sleep apnea

This is a breathing disorder during sleep that has the characteristics of the two previous ones: the breathing problem begins with a central apnea in which the effort to breathe is greatly diminished, but when it returns to normal rhythms, a real obstruction of the airways appears that usually generates the awakening of the subject.

4. Upper airway resistance syndrome

Syndrome of lesser severity than the others in which there is no decrease in the levels of oxygen received . This disorder is characterized by the presence of awakenings during sleep, without the appearance of an apnea episode. The problem in this case seems to be linked to an increase in the effort made to breathe. Intense snoring often occurs as a result of this effort. It also tends to generate daytime sleepiness.

5. Hypoventilation syndromes

These syndromes are characterized by the fact that, unlike apneas, there is no period of time when there is a complete cessation of breathing. These are syndromes in which the subject who suffers them has some type of deficiency in the respiratory system that causes a sufficient level of air to fail to reach the body, generally with breathing being superficial. Less oxygen reaches the brain and there is an increase in the levels of carbon dioxide in the blood.

It is not uncommon for snoring to occur , and like the previous ones it usually causes fatigue, memory problems and some nighttime awakenings. We speak of syndromes because there are several that could be included in this category, such as Ondina syndrome (caused by congenital alteration of respiratory control).

Causes of these disorders

The reasons for the appearance of some kind of breathing disorder during sleep can be multiple, both genetic and environmental.

Alterations of a biological and genetic nature are found in the presence of cranial malformations or in hypertrophies of organs such as the tongue or the tonsils , or in different syndromes and diseases, both genetic and acquired.

One of the most relevant controllable risk factors is obesity: the increase of fatty tissue especially around the throat can exert a weight and pressure on the airways that hinders the passage of air. Obstruction and deterioration of these airways can also contribute to the creation or maintenance of a breathing disorder during sleep, such as tobacco use. Allergies are also a possible reason for their occurrence.

They may also be linked (as in the case of central apneas) or derive from the presence of a heart disease or brain injury that may be caused by infections, cardiovascular or cerebrovascular accidents, tumours, respiratory diseases or head injuries.

Treatment

The treatment of respiratory disorders during sleep can be carried out in many ways depending on the needs and capabilities of the patient, as well as his or her personal characteristics.

One of the options available is to make a weight loss plan in the case of obstructive apnea, along with the avoidance of airway irritants.

Different drugs can be used in the treatment, although they are usually not very effective. The exception may be if we are dealing with a patient whose obstruction is allergic or derived from different diseases expressed on time. In these cases , the disease or alteration that causes or facilitates the alteration of breathing during sleep must be treated .

A common mechanism for treatment is the use of continuous positive airway pressure (CPAP) equipment. This is a mechanism that provides continuous pressure through a mask placed in the nose and/or mouth, allowing continuous lung functionality by keeping the airway open. It is applied in those patients in whom nocturnal breathing problems are very frequent and do not respond to sleep hygiene and other treatments, and aims to achieve the cessation of apneas and limitation of respiratory flow.

In some cases surgical intervention is required , for example when hypertrophies occur in the tonsils or even on the tongue. Alternatives such as the use of dentures or mandibular advancement devices can also be used.

Bibliographic references

  • Nazar, G. (2013). Sleep-disordered breathing in children. Revista Médica Clínica Las Condes, 24: 403-411. Elsevier.