Adult Snoring, Sleep Apnoea and Sleep Disordered Breathing (adapted from a recent article written by Dr Novakovic for a Sydney Medical publication)
What is Sleep Disordered Breathing?
Sleep Disordered Breathing (SDB) refers to abnormal respiratory patterns during sleep. Almost all patients with SDB snore, but not all patients who snore have SDB. Snoring without SDB is called simple snoring
What is Obstructive Sleep Apnoea ?
Obstructive Sleep Apnoea Syndrome (OSAS) is a potentially serious type of SDB characterised by snoring, excessive daytime sleepiness, nocturnal hypoxia and repeated episodes of airway obstruction during sleep. Untreated OSAS increases the risk of hypertension, diabetes, cardiovascular disease, depression and obesity with sufferers carrying a 30% higher risk of myocardial infarction or death.
What is Upper Airways Resistance Syndrome?
Upper Airways Resistance Syndrome (UARS) is a subset of SDB characterised by snoring with increased respiratory effort and airway resistance and frequent sleep arousals without oxygen desaturation or obstructive events. It differs from OSAS in that it occurs in younger, thinner patients and equally between sexes. But presenting symptoms and treatments are the same as OSAS.
How common are snoring and Obstructive Sleep Apnoea?
Up to 40% of adults snore. The prevalence of OSAS is unclear, but it is thought that up to 10% of adult males and 5% of adult females have OSAS
What are the risk factors for OSA?
- Age – OSA is most common in middle age. Incidence increases with age especially postmenopausal women
- Sex – OSA and snoring are twice as common in males
- Weight – OSA and snoring incidence increases with BMI. Up to 40% of obese males have OSAS and 70% of people with OSAS are obese
- Decreased muscle tone – including sedative and alcohol use
- Craniofacial syndromes – including Down Syndrome
- Hypothyroidism (low thyroid function)
- Structural/anatomical features leading to upper narrowing airway
What are the important features on clinical assessment of the upper airway in snoring/OSA?
- Nasal obstruction (blocked nose) – airway restriction due to turbinate hypertrophy or deviated nasal septum is important to identify as simple medical / surgical treatments for the nose may significantly improve sleep quality
- Micrognathia/retrognathia (small chin) – may be familial
- Long oedematous soft palate – should prompt questioning about snoring / OSA symptoms
- Tonsillar hypertrophy – Removal of large tonsils can significantly improve airway obstruction
- Macroglossia (large tongue) – can obstruct the airway especially when supine. Oral appliances (to bring the jaw and tongue forward) or surgery (to reduce the size of the tongue) may have significant immediate benefits in these patients
- Other features such as craniofacial anomalies, overbite, large neck circumference and narrow maxillary arch should also be noted
How do we diagnose OSAS?
- Clinical history of daytime sleepiness or witnessed apnoea should prompt referral for a sleep study
- A sleep study or polysomnogram is usually performed “in hospital” but there are also a number of “take home” tests that may be appropriate for some patients
- Sleep study measures should include airflow, respiratory effort and blood oxygen levels amongst others
- Obstructive apnoea – refers to total absence of airflow with respiratory effort
- Hypopnoea – refers to reduction in airflow by 50% with respiratory effort
- The Respiratory Disturbance Index (RDI) or Apnoea Hypopnea Index (AHI) is a measure of the number of apnoeas or hypopnoeas lasting 10 seconds or longer per hour of sleep.
- An RDI/AHI of 5 or more is considered abnormal and suggests OSA and the absolute number is used to classify severity (see table).
AHI Rating
<5 Normal
5-15 Mild
16-30 Moderate
>30 Severe
What are the treatment options for snoring/OSA?
Behavioural modification is an important first step. Patients should be advised to get a minimum 6–7 hours of sleep and to avoid sleeping supine. Sedatives including alcohol decrease muscle tone and should be avoided. Patients should also be educated about the risk of excessive daytime sleepiness especially when driving or operating machinery
Weight Loss should be advised for overweight/obese patients. A reduction in neck diameter equates to an increase in the internal airway diameter. A 10% weight loss was associated with a 26% decrease in the AHI in one study.
Nasal obstruction should be addressed. Breathing against a blocked nose will increase negative airway pressure and tissue collapse. Medical treatment of blocked nose may lead to a surprising improvement in snoring severity. Patients with anterior nasal valve collapse may benefit from “Breath Right” strips to help airflow at night.
CPAP or Continuous positive airway pressure remains the gold standard treatment of OSA and works very well if tolerated by the patient. Non-compliance to CPAP remains a significant problem.
Oral Appliances are indicated in mild to moderate OSA or for those unable to use CPAP and can often be successful in simple snoring. They work by bringing the lower jaw and tongue forward to improve pharyngeal airway.
Surgery does have a role in some patients however no single surgical procedure is universally successful. The goals of sleep surgery are to:
– Address any easily modifiable anatomic factors such as large tonsils or nasal obstruction
– Increase compliance to CPAP in patients with sleep apnoea
– Improve AHI in patients unable to tolerate CPAP
It is important to remember that surgery is not a substitute for CPAP in the treatment of moderate to severe sleep apnoea. Success rates for surgery alone are poor in the obese group of patients. An ENT surgeon will be able to perform a careful multilevel assessment of the upper airway to determine the level of obstruction and whether a surgical approach should be considered.
Surgical treatment of snoring also relates to multilevel assessment. In the absence of OSA there are excellent surgical options to improve snoring.
What are the common surgical procedures used for Snoring / Sleep Apnoea?
Clinical assessment by an ENT surgeon will help identify any easily rectifiable anatomical factors.
Muller’s Manoeuvre involves breathing in against a blocked mouth and nose – with a flexible nasoendoscope / telescope in situ this may help us assess the level of airway collapse
Septoplasty and Inferior turbinate reduction may be indicated in cases of nasal obstruction. Restoring laminar nasal airflow can reduce the respiratory effort necessary for inspiration
Tonsil / adenoid removal may be considered as a first line treatment in people with enlarged tonsils or in the case of adenoid tissue obstructing the post nasal space
Modified Uvulopalatopharyngoplasty (modified UPPP) is a newly developed operation aimed at expanding the retropalatal airway and reducing soft tissue vibration. It differs from the old UPPP operation in its tissue preserving approach and has higher success rates
Coblation tongue base reduction has recently evolved as the preferred minimally invasive method for addressing large tongues. It is well tolerated with a favourable safety profile.
Conclusion
Snoring and sleep apnoea remain prevalent conditions in today’s society. Management remains a multidisciplinary approach aimed towards improving patient quality of life.
Studies show that sleep apnea can also be associated with other ENT disorders including laryngopharyngeal reflux disease and voice problems. It is highly recommended that anyone suffering from suspected sleep apnea contact an appropriate health professional for diagnosis and treatment. Via an appropriate sleep apnea clinic, good management options are available to improve sleep related quality of life.
Dr Novakovic believes it is important to actively ask patients about symptoms of sleep disordered breathing. We have access to the latest sleep diagnostic centres across Sydney and also take part in the multidisciplinary sleep meetings at Royal North Shore Hospital. SVAS is a specialist clinic that can help assess and manage snoring and sleep apnea Sydney wide.