Snoring

Overview of snoring

Different types of sleep disorders are observed in both children and adults. These complications tend to become more common with age. According to the global estimates of the National Sleep Foundation of America, nearly 150 million people all over the world suffer from some or the other form of sleep disorder. Very often, these disorders are worsened by environmental, psychological and physiological factors. “Snoring” is the most common sleep disorder that is observed in people belonging to all age groups and genders. Based on the annual reports of the American Academy of Sleep Medicine, nearly 60% of the adult population of the world suffer from this disorder.

Definition of snoring

Snoring is defined as the unpleasant sound generated due to the vibrations of different parts of the respiratory tract caused by obstructed air movement during sleeping. It is often called “Obstructive Sleep Apnea”, though the nomenclature is not medically correct.

It mainly occurs due to vibration of the pharyngeal muscles during inhalation.

During sleeping, the muscles of the pharynx become very relaxed and cause partial blockage of the respiratory passage.

This causes an obstruction in the normal flow of air across the upper respiratory tract. More effort is applied for breathing in these situations due to the constant vibration of the soft tissues of the throat namely – uvula and soft palate. This leads to the generation of noise.

Difference between snoring and obstructive sleep apnea

In obstructive sleep apnea, a temporary collapse of the throat muscles occurs, resulting in complete cessation of breathing for a period of 5-90 seconds. On the contrary, when a person snores, the throat muscles relax but do not collapse completely. The breathing is irregular in this case but never stops completely. 

What causes snoring?

Multiple factors can make a person snore. The important causes are listed below-

• Nasal obstruction: Blockage of the nasal passage is often caused due to the accumulation of excess mucus. In such cases, turbulent flow is induced in the upper respiratory tract due to increased resistance in the nasal passage. This leads to “oral breathing”. This, in turn, induces excessive vibration of the pharyngeal muscles and soft tissues of the throat, causing a person to snore. In this context, it has to be noted that the muscles at the back of the mouth are more floppy than the muscles present at the back of the nose. Hence snoring due to nasal breathing is not as intense as the one that occurs in “mouth breathing”.
• Oropharyngeal obstruction: The oropharyngeal region consists of the tonsil, pharynx and the soft palate. Obstruction of this region may occur due to some existing respiratory disorders, accumulation of mucus or instrumental surgeries carried out in the past. Often, the presence of a redundant tissue may exacerbate the condition. All these factors can cause a person to snore.
• Hypopharyngeal obstruction: Obstruction at the retrolingual area (situated at the base of the tongue) may occur due to the presence of excess tongue mass. This may make a person snore.
• Obesity: Obese and overweight people often have deposition of excess fat and adipose tissues outside and also within the throat. This causes narrowing of the passage and leads to snoring.
• Alcohol consumption: Alcohol consumption on a regular basis causes excessive toning of the throat muscles. Chronic alcoholics tend to snore more than normal people.
• Smoking: Excessive tobacco consumption can cause irritation of the throat muscles. Narrowing of the throat passage may occur in active smokers, leading to snoring.
• Sleeping position: Lying on the back while sleeping can cause partial obstruction of the air passage due to the tongue placed at the back of the mouth.
• Tumors: Tumors or lumps present anywhere within the respiratory passage can cause a partial blockage. This is often observed in people having an enlarged thyroid gland, nasal polyps, nasal sepsis or an abnormally large tongue. Children suffering from adenoiditis or tonsillitis often exhibit problems like snoring and sleep apnea.
• Allergy: Allergies caused by certain seasonal triggers such as pollen grains or other allergens such as animal dander, bristles or some sea-foods can lead to irritation and a sense of choking. The respiratory passage is temporarily obstructed in such cases, leading to snoring.
• Congenital defects: Some people can have a very narrow air passage from birth. This may be further exacerbated by abnormal shapes of the jaw, tongue, face or nasal passage. All of these factors can equally contribute to snoring.
• Medications: A few over-the-counter drugs such as sedatives, anti-depressants, steroids, anesthetics etc can cause excessive relaxation of the throat muscles during sleep. Snoring occurs in most of these cases.
• Breathing pattern: Some people habitually breathe through their mouth even under normal healthy conditions. These people are more likely to experience snoring.

What are the different types of snoring?

Snoring is broadly classified into two types-

• Simple: It refers to the normal snoring due to excessive muscle relaxation.
• Disruptive: This is defined as intermittent snoring which occurs due to normal functioning of the throat muscles for a certain period of time and obstruction of the air passage during the remaining period. Complete cessation of respiration may occur in some cases, making the person wake up in the middle of the night.

Another classification of snoring is given below-

• Vibratory: This is caused due to excessive oscillation of the floppy throat muscles during sleeping.
• Stenotic: This type of snoring is caused by the narrowing of the respiratory passage.

What diagnostic tests do the doctors recommend?

The following diagnostic techniques are recommended by doctors to determine why a person snores-

• Polysomnography (to determine the severity of the disorder)
• MRI scan
• Upper airway endoscopy (to detect the site of respiratory tract responsible for the disease)

Treatment & Prevention

Snoring can be treated by the following methods:

• Lifestyle modifications- some changes in the lifestyle include losing weight, treating nasal congestion, avoiding alcohol close to bedtime, avoiding sleep deprivation, sleeping on your side etc.

In cases where obstructive sleep apnea is observed with snoring, the following may be recommended:

Oral appliances– These are appliances fabricated to alter/advance the position of the jaw, tongue, and soft palate with the aim of keeping the airway patent. The appliances are customized according to your jaw size and fabricated by a dentist.  The devices might cause excessive salivation, jaw pain, dry mouth and facial discomfort in the initial stages.

• Continuous positive airway pressure (CPAP) – This method comprises a bedside pump that pumps pressurized air into your airway through a mask that is connected via a tube. This helps to keep the airway open during the sleep throughout the night.
• Surgical intervention– Certain surgical procedures help in keeping the airway open during sleep and prevent the substantial narrowing of the upper airway. Some of the surgical procedures are uvulopalatopharyngoplasty (UPPP)- excess tissue in the throat is tightened and trimmed, maxillomandibular advancement (MMA)- it helps in opening the airway by the forward positioning of the upper and the lower jaw.
• Radiofrequency tissue ablation– This procedure makes use of a low-intensity radiofrequency signal with the aim of shrinking the soft tissue present in the nose, soft palate or tongue.

Prevention of snoring is mainly by getting rid of obesity, practicing sleep hygiene and changing the sleep position so as to keep the airway open. Use of nasal strips or an external nasal dilator can also help in preventing snoring. Consumption of alcohol should be avoided close to bedtime and smoking should be stopped completely.

 
References