Sleep Apnoea

What Is Sleep Apnoea? The Anatomy of the Upper Airway

Sleep apnoea is a breathing disorder that develops when the upper airway repeatedly closes during sleep, or when the brain temporarily fails to send breathing signals. It fragments sleep and lowers the level of oxygen in the blood. Also known by its medical name obstructive sleep apnoea syndrome (OSAS), the condition most often arises from a mechanical obstruction.

The upper airway is a dynamic tube made up of the nose, nasopharynx, soft palate, uvula, tonsils, base of the tongue, hypopharynx and the upper part of the larynx. As the muscles relax during sleep, this tube narrows; in some people it becomes partially blocked (hypopnoea) or completely blocked (apnoea). Any pause lasting 10 seconds or longer is counted as an “apnoea”, while reduced but not fully arrested airflow is counted as a “hypopnoea”.

Types of apnoea:

• Obstructive apnoea (OSAS): The most common type. The airway closes mechanically while the chest and abdomen continue to make breathing efforts.
• Central apnoea: The brain does not send the command to breathe, and there is no respiratory effort from the chest.
• Mixed (complex) apnoea: A picture in which both types occur together.

This article mainly addresses obstructive sleep apnoea, which is the form most frequently encountered in ear, nose and throat practice.

When Is Sleep Apnoea Considered?

Sleep apnoea is not simply “noisy snoring”. The following clinical clues prompt an ENT or sleep physician to arrange further assessment:

• Regular, loud snoring combined with pauses in breathing
• A partner’s description that “the breathing stops and then starts again with a gasp”
• Sudden awakenings during sleep, waking with a sensation of choking
• Morning headaches, a dry mouth, waking unrefreshed
• Marked daytime sleepiness (during meetings, in traffic, while reading)
• Frequent urination (two or more times a night)
• Irritability, difficulty concentrating, complaints about memory
• Treatment-resistant hypertension
• Atrial fibrillation, night-time rhythm disturbances
• Type 2 diabetes, metabolic syndrome
• Obesity, a neck circumference above 43 cm in men and 38 cm in women
• In children, persistent mouth breathing, restless sleep at night and a decline in school performance

Symptoms and Causes

Night-time symptoms

• Loud, irregular snoring
• Witnessed pauses in breathing
• Waking with a sensation of choking or interrupted breathing
• Frequent changes of position
• Sweating
• Frequent urination
• Dry mouth
• A sensation of reflux at night

Daytime symptoms

• Waking unrefreshed, morning headaches
• Dozing during the day, micro-sleeps
• Difficulty with concentration and memory
• Irritability, impatience, mood swings
• Reduced libido
• An increased risk of traffic and workplace accidents

Factors that trigger apnoea

• Obesity — the strongest modifiable risk factor
• A thick neck circumference
• Anatomical narrowing: large tonsils, adenoids, a long soft palate or uvula, a large tongue, a recessed jaw (retrognathia), a narrow upper jaw
• Nasal obstruction: a deviated septum, turbinate hypertrophy, polyps
• Male sex and post-menopausal women
• Advancing age
• A family history
• Use of alcohol, tobacco and sedative medication
• Endocrine conditions such as hypothyroidism and acromegaly
• The supine sleeping position — in some patients this can be the sole trigger of apnoea

The Diagnostic Process: Polysomnography Is the Gold Standard

A diagnosis of sleep apnoea is made through the patient’s history, a physical examination and an objective sleep study. It is not appropriate to tell someone “you have sleep apnoea” on the basis of symptoms alone, because the spectrum ranges from mild snoring to severe apnoea, and the choice of treatment rests precisely on this objective data.

1. A detailed history and screening scales. Tools such as the Epworth Sleepiness Scale and the STOP-BANG questionnaire are used in assessing risk.
2. ENT examination. The nose (septum, turbinates, polyps), the mouth (tonsil size, tongue position — the Mallampati score), the soft palate, uvula, base of the tongue and jaw structure are evaluated. In selected cases, DISE (drug-induced sleep endoscopy) shows at which level the obstruction occurs.
3. Polysomnography (PSG). A fully equipped sleep study carried out in a sleep laboratory. Brain waves (EEG), eye movements, heart rhythm, respiratory effort, airflow, blood oxygen and leg movements are recorded simultaneously.
4. The Apnoea–Hypopnoea Index (AHI). The average number of apnoeas plus hypopnoeas per hour.
   • AHI < 5: normal
   • AHI 5–15: mild apnoea
   • AHI 15–30: moderate apnoea
   • AHI > 30: severe apnoea
5. A home portable sleep study. An alternative in selected patients; however, it does not replace PSG in complex cases.
6. Supporting assessments. Cardiology (hypertension, rhythm disturbance), endocrinology (diabetes, thyroid) and, where necessary, psychiatry or neurology are involved.

In the approach to apnoea, the standard practice is for the ear, nose and throat physician, the respiratory physician and the sleep centre to work together.

Treatment Approaches: From Conservative to Surgical

The choice of treatment is individualised by considering the AHI, the degree of oxygen desaturation, the anatomical level of obstruction, body weight, coexisting conditions and patient preference together.

1. Lifestyle changes

These form the foundation of every treatment plan:

• Weight loss — the single most effective measure. A 10% reduction in body weight markedly lowers the AHI.
• Avoiding sleeping on the back (where positional apnoea is present)
• Limiting alcohol and sedatives before bedtime
• Stopping smoking
• Regular sleep hours and good sleep hygiene
• Raising the head of the bed and managing reflux

2. Positive airway pressure (PAP) devices

The first-line treatment for moderate to severe obstructive sleep apnoea is a PAP device:

• CPAP (continuous positive pressure): standard use.
• APAP (automatically adjusting): for patients whose pressure requirement varies from night to night.
• BPAP / BiPAP (bilevel): for patients who need high pressures or who struggle to breathe out.

A PAP device keeps the airway pneumatically open. With correct mask selection, pressure titration and patient education, the rate of success rises significantly.

3. Oral appliances (mandibular advancement devices)

Custom-made by a dentist, these appliances widen the airway by bringing the lower jaw forward. They are an alternative in mild to moderate apnoea, for patients who cannot tolerate CPAP, and particularly in cases where snoring is the predominant feature.

4. Surgical treatment (the ENT perspective)

Surgery is chosen after the level of obstruction has been established with sleep endoscopy (DISE). It is not “a single operation” but is often a multi-level approach:

• Nasal surgery (septoplasty, turbinate reduction, polyp surgery): improves CPAP tolerance; on its own it rarely resolves apnoea.
• Soft palate / uvula procedures (UPPP, radiofrequency, plasma-assisted techniques).
• Tonsil surgery (particularly important in young adults and children with large tonsils).
• Tongue base procedures (radiofrequency, hypoglossal nerve stimulation in selected cases).
• Maxillomandibular advancement (MMA) — an advanced procedure in which the lower and upper jaws are moved forward together; highly effective in severe cases.

In children, the most common solution is the removal of enlarged adenoids and tonsils, and the results are generally very gratifying.

5. Adjunctive treatments

• Positional devices (belts or vests that prevent sleeping on the back)
• Medical treatment directed at allergic rhinitis, reflux and obesity
• Bariatric surgery in selected patients with morbid obesity

The Process and Recovery

The treatment journey is not a one-off intervention but long-term management.

• PAP therapy: The first few weeks are a period of getting used to the mask. Mask leak, a dry mouth and a sensation of pressure are common complaints, and the great majority are resolved with a suitable mask and a humidifier. It is critical for success that the patient uses the device for at least 4 hours each night, and ideally 6 hours or more.
• After surgery: Depending on the procedure performed, there may typically be a sore throat, hoarseness and difficulty swallowing for 1–2 weeks. With multi-level surgery, recovery may extend to 3–4 weeks. Plenty of fluids, soft foods, pain control and oral hygiene are important.
• Children’s operations: Recovery usually occurs within 7–10 days; the disappearance of snoring and restless night-time sleep within a short period is a typical observation.

Quality of Life and Long-Term Follow-Up

Untreated sleep apnoea is not merely a matter of “waking up tired”. Over the long term it increases the risk of the following complications:

• Hypertension (particularly when it is treatment-resistant)
• Coronary heart disease and heart failure
• Atrial fibrillation and night-time rhythm disturbances
• Stroke
• Type 2 diabetes and metabolic syndrome
• Traffic and workplace accidents
• Depression and cognitive decline

Changes that may be expected to improve with the correct treatment:

• Greater daytime energy and alertness
• A reduction in morning headaches
• A marked improvement in the quality of life of the partner and family
• Easier control of blood pressure and blood sugar
• Less night-time urination
• A noticeable improvement in mood

In long-term follow-up:

• Repeating the sleep study annually (or as required when symptoms change)
• For those using a PAP device, reviewing the adherence data (hours per night, AHI) together with the physician
• Parallel management of weight, alcohol, sedative use and coexisting conditions
• Where surgery has been performed, a post-operative follow-up sleep study is recommended

Sleep Apnoea in Children

Sleep apnoea in children differs in important ways from the adult form, and overlooking it can seriously affect a child’s development.

The most common cause of apnoea in children is enlarged adenoids and large tonsils. Obesity, allergic rhinitis, a narrow upper jaw, craniofacial syndromes and conditions such as Down syndrome make up the other risk factors.

Sleep apnoea should be considered in a child when the following findings are present:

• Loud snoring and irregular breathing at night
• Frequent changes of position at night, sweating, sleeping with the mouth open
• Bed-wetting (beyond the age-appropriate stage)
• Morning headaches, waking listless
• Excessive daytime sleepiness or, conversely, hyperactivity and inattention
• A decline in school performance and problems with concentration
• Problems with growth and weight gain
• Persistent mouth breathing, dry lips and poor oral hygiene
• Signs of facial and jaw development such as a long face, a narrow upper jaw and an anterior crossbite

In children with apnoea, adenoidectomy ± tonsillectomy produces a large improvement in the picture in most cases. Where obesity coexists, weight management and, if necessary, positive airway pressure therapy are introduced. Early diagnosis is critically important for the child’s growth, behaviour and facial and jaw development.

Common Misconceptions

• “If I snore, I must have apnoea.” Not every instance of snoring means apnoea; but persistent snoring should always be assessed.
• “You cannot get used to CPAP.” With correct mask selection, pressure titration and support for adherence, the great majority do adapt.
• “If I have surgery, I will be free of CPAP.” This is true in some cases, but it cannot be predicted in every patient. The surgical plan is made with sleep endoscopy, and a follow-up PSG after surgery is recommended.
• “I have apnoea but I’m not tired during the day, so there’s no need.” The cardiovascular and metabolic effects of apnoea can develop even without sleepiness; treatment is undertaken not only for comfort but for long-term health.
• “Snoring is natural as you get older.” It does increase with age, but it cannot be regarded as natural.

When Should a Specialist Be Consulted?

A consultation with an ENT or sleep physician for sleep apnoea is warranted if any of the following applies:

• Loud, irregular snoring with witnessed pauses in breathing
• Waking with a sensation of choking
• Daytime sleepiness and waking unrefreshed lasting longer than 6 months
• Dozing or micro-sleep episodes in traffic or at work
• Treatment-resistant hypertension, atrial fibrillation
• Obesity combined with loud snoring
• In a child, restless sleep at night, sleeping with the mouth open, persistent snoring and a decline in school performance
• A return of symptoms after previous treatment for apnoea

Sleep apnoea is a condition that progresses silently yet can have serious cardiovascular, metabolic and cognitive consequences. With early diagnosis and the correct stepwise treatment, the great majority can be managed safely; its beneficial effect on quality of life and long-term health is considerable.