What is Obstructive Sleep Apnea?

The most prevalent sleep-related breathing disease, obstructive sleep apnea (OSA), is characterized by recurring episodes of whole or partial obstruction of the upper airway, which results in diminished or absent breathing during sleep. These events are classified as “apneas” when breathing completely or nearly completely stops, or as “hypopneas” when breathing is just partially reduced. In either scenario, there may be a drop in blood oxygen saturation, a sleep disturbance, or both. When blood oxygenation is disturbed and apneas or hypopneas occur frequently while you sleep, it may affect the quality of your sleep, which is thought to hurt your health and quality of life. When OSA is linked to daytime symptoms (such as excessive daytime drowsiness and poor cognitive performance), it is referred to as obstructive sleep apnea syndrome (OSAS) or obstructive sleep apnea-hypopnea syndrome (OSAHS).

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Even after awakening, most people with obstructive sleep apnea are not aware of breathing irregularities while they are asleep. A family member or bed partner may notice someone snoring, appearing to cease breathing, gasping, or choking while they are asleep. Many times, those who sleep or live alone are unaware of the problem. Without a diagnosis, symptoms may persist for years or even decades, during which the person may adapt to the daytime sleepiness, headaches, and exhaustion that are brought on by severe levels of sleep disturbance. Snoring is linked to neurocognitive problems, and obstructive sleep apnea has been linked to neurocognitive morbidity

Classification

Obstructive sleep apnea is one of the sleep-related breathing diseases and is separated into two groups, adult OSA and pediatric OSA, in the third edition of the International Classification of Sleep Diseases (ICSD-3).[1] Central sleep apnea (CSA), which is distinguished from obstructive sleep apnea by bouts of reduced or stopped breathing related to diminished effort rather than upper airway blockage, is distinguished from CSA. Given the uniqueness of the diaphragmatic activity in this state, the respiratory effort must then be evaluated to appropriately characterize the apnea as obstructive: the inspiratory effort is maintained or augmented throughout the whole episode of absent airflow.

Obstructive sleep apnea-hypopnea is the name used when hypopneas coexist with apneas, while obstructive sleep apnea-hypopnea syndrome is used when it is combined with daytime sleepiness and other symptoms of the day. The hypopnea must exhibit one or more of the following symptoms to be classified as obstructive: (1) snoring during the occurrence, (2) increased oronasal flow flattening, or (3) thoracoabdominal paradoxical respiration. Central hypopnea is the term used when none of them occur throughout the episode.

Obstructive Sleep Apnea: Signs and symptoms

Unaccounted-for daytime tiredness, restless sleep, and loud snoring (accompanied by quiet followed by gasps) are all common signs of OSA syndrome. Morning headaches, inability to sleep, difficulty concentrating, mood swings like agitation, anxiety, and depression, forgetfulness, an increase in heart rate or blood pressure, a decrease in sex drive, an unexplained increase in weight, an increase in nocturia or urinary frequency, frequent heartburn or gastroesophageal reflux, and night sweats that are very heavy are less frequent symptoms.

Many people have transient OSA episodes, which last barely a moment or two. This may be the result of tonsillitis, which momentarily causes abnormally enlarged tonsils, or an upper respiratory infection, which results in nasal congestion and throat swelling. For instance, the Epstein-Barr virus can significantly expand the amount of lymphoid tissue during acute infection, and OSA is rather typical in severe infectious mononucleosis with acute manifestations. People who are under the influence of a substance (like alcohol) that may cause them to relax their body tone excessively and interfere with regular arousal from sleep mechanisms may also have brief episodes of OSA syndrome.

Obstructive Sleep Apnea in Adults

Excessive daily sleepiness in adults is the primary symptom of OSA syndrome. An adult or adolescent with severe, long-term OSA would typically nod off for very brief durations while engaging in routine daily activities if provided the chance to sit or rest. This behavior can often be rather spectacular, happening while people around you are conversing in social settings.

The neurons in the right frontal cortex and the hippocampus may change as a result of the OSA-related hypoxia (lack of oxygen supply). Neuroimaging studies found indications of hippocampus shrinkage in OSA sufferers. They discovered that OSA can impair executive skills, working memory, and the ability to mentally manipulate non-verbal information.[Reference needed] Alzheimer’s disease is thought to be caused by persistent brain hypoxia.

Obstructive Sleep Apnea in Children

Even though children can also experience this so-called “hypersomnolence” (extreme sleepiness), it is not at all characteristic of young children with sleep apnea. Instead, toddlers and young children with severe OSA typically exhibit “over-tired” or “hyperactive” behavior, and typically display behavioral issues like impatience and a lack of concentration.

The usual body habits of adults and children with very severe OSA vary as well. Adults tend to be heavy, with their necks being particularly short and heavy. On the other side, young children tend to be slender and may also have “failure to thrive,” which results in slower growth. Poor growth happens for two reasons: eating is unpleasant to do and causes physical discomfort, and breathing requires so much energy that calories are consumed quickly even when resting. In contrast to adults, children’s OSA is frequently brought on by obstructive tonsils and adenoids, and it occasionally responds to tonsillectomy and adenoidectomy.

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Children who are overweight may also experience this issue. In this instance, the symptoms resemble those that adults experience more, such as agitation, fatigue, etc. If adenotonsillar hypertrophy continues to be the most frequent cause of OSA in children, obesity may also contribute to the pathophysiology of upper airway obstruction during sleep, increasing the likelihood that obese children will acquire OSA. Thus, the frequency and characteristics of pediatric OSA have changed as a result of the recent pandemic rise in obesity prevalence, with the severity of OSA being inversely correlated with the degree of obesity.

Due to fatty infiltration and fat deposits in the anterior neck region and cervical tissues, obesity causes the upper airway structure to constrict. It decreases the intrathoracic volume and diaphragm excursion while increasing the danger of pharyngeal collapsibility in addition to the greater weight loading on the respiratory system. Additionally, severe daytime sleepiness brought on by interrupted sleep might reduce physical activity and thus cause weight gain (via sedentary behaviors or increased food intake to combat somnolence).

There are two forms of OSA in children, according to some writers, because of the relationship between obesity and upper airway obstruction: Type I is connected to pronounced upper airway lymphadenoid hyperplasia without obesity, whereas type II is first connected to both obesity and a milder form of this condition. The two kinds of OSA in kids can have various morbidities and effects. Studies have indicated that among obese teenagers, losing weight helps lessen sleep apnea and the associated OSA symptoms.

Obstructive Sleep Apnea: Risk factors

Obesity

Obesity is a common symptom of OSA in children, adolescents, and adults. Obese adults have more neck fat tissue, which might worsen sleep-related respiratory obstruction.

All ages and genders can, however, have OSA and those with normal body mass indices (BMIs) do not have appreciable amounts of subcutaneous or intra-neck fat, as revealed by DEXA scans. They are thought to have more muscular mass or a propensity for lower muscle tone, which can exacerbate airway collapse when they sleep.

Even though obesity seems to be a frequent association with deep sleep, OSA is not always accompanied by fat. Loss of muscular tone is instead a fundamental characteristic of deep sleep.

The risk of OSA is also increased by sleeping supinely (on one’s back). The development of OSA is unquestionably caused by gravity and the decrease of tongue and throat tone as a person enters deep sleep. However, the existence of neck obesity further complicates this theory.

The use of CPAP would demonstrate that airway collapse is the root cause of OSA because it definitively expands a collapsed upper airway, allowing for nasal breathing.

The removal of throat lesions, particularly enormous tonsils, may bring about full, partial, or semi-permanent relief from OSA. This suggests that swollen tonsils may contribute to the etiology of OSA

Age

Loss of upper airway muscle tone due to neurological and muscular degeneration is a common symptom of old age. Chemical depressants can also temporarily lower muscular tone; the most popular ones are alcoholic beverages and sedative drugs

Muscle tone

People who have structural characteristics that lead to a constricted airway, lower muscle tone, increased soft tissue around the airway, or both are at a greater risk for OSA. Men, whose anatomy is characterized by higher bulk in the torso and neck, are more likely to develop sleep apnea, especially as they become older and reach middle age.

Lifestyle

Smoking increases the risk of developing OSA because the chemical irritants in smoke tend to swell the soft tissue of the upper airway and encourage fluid retention, both of which can cause the airway to narrow. Smoking may also have an effect because it lowers blood nicotine levels, which changes the stability of sleep

Obstructive Sleep Apnea: Treatment

Obstructive sleep apnea is treated with a variety of methods. It is advised to abstain from alcohol, smoking, and drugs that depress the central nervous system (such as sedatives and muscle relaxants). For those who are overweight, weight loss is advised. Both mandibular advancement devices and continuous positive airway pressure (CPAP) are frequently employed and are successful. Even without losing weight, physical exercise reduces sleep apnea. The data is not strong enough to warrant widespread pharmaceutical use. Tonsillectomy is advised in some people, such as those who have tonsillar hyperplasia. Surgical intervention with conservative uvulopalatopharyngoplasty (UPPP) as salvage surgery is advised for individuals who are not responding to CPAP and oral appliances.

Physical intervention

Positive airway pressure, in which a breathing apparatus pumps a controlled stream of air through a mask worn over the nose, mouth, or both, is the most frequently employed therapeutic technique.

• Both mild and severe illnesses can be treated with continuous positive airway pressure (CPAP). It is the preferred method of treating obstructive sleep apnea.

• Variable positive airway pressure (VPAP), often referred to as bilevel (BiPAP or BPAP), employs an electronic circuit to monitor the patient’s breathing while delivering two separate pressures—a higher pressure during inhalation and a lower pressure during expiration. This more expensive equipment is occasionally utilized with individuals who either have other respiratory issues or who find it difficult or disruptive to breathe out against increasing pressure.

• Nasal EPAP, which uses a bandage-like device placed over the nostrils to provide positive airway pressure to prevent breathing obstructions.

• Automatic positive airway pressure (often referred to as “Auto CPAP”) incorporates pressure sensors and tracks the patient’s breathing.

• In people with moderate to severe OSA, a 5% weight loss may reduce symptoms comparably to CPAP.

Rapid Palatal Expansion

Children frequently receive orthodontic treatment, such as nonsurgical Rapid Palatal Expansion, to increase the size of the nasal airway.

Adults cannot conduct routine RPE using tooth-borne expanders because the palatal suture is fused. A non-surgical alternative for the transverse extension of the maxilla in adults has recently been created, and it is called mini-implant-assisted rapid palatal expansion (MARPE). This technique expands the nasal cavity and nasopharynx, resulting in greater airflow and fewer respiratory awakenings while you sleep. Permanent changes are made with few problems.

Surgery

The many surgical procedures used in so-called “sleep surgery,” which modifies the structure of the airways, must be specifically adapted to each patient’s demands in terms of airway obstruction. Surgery is not regarded as the first line of treatment for individuals with obstructive sleep apnea

Neurostimulation  To prevent the tongue from collapsing over the airway in patients who are unable to use a continuous positive airway pressure device, the U.S. Food and Drug Administration in 2014 granted pre-market approval for an upper airway stimulation system that detects breathing and administers mild electrical stimulation to the hypoglossal nerve. The device is powered by an implantable pulse generator, similar to one used for cardiac rhythm management, and incorporates a handheld patient controller to enable it to be turned on before sleeping