Obstructive Sleep Apnoea

Snoring ⬎

Snoring is the sound created when air flows past relaxed tissues in your throat causing them to vibrate as you breathe. These noises can be a social issue if it disturbs your partner's sleep and often results in couples sleeping in separate rooms. Some people may only snore occasionally, but others may snore continuously throughout the night.

Snoring may be an indication of a more serious health condition called Obstructive Sleep Apnoea (OSA), covered above.

What should I do if I snore?

We would suggest speaking to your GP about whether you may be at increased risk of having obstructive sleep apnoea. If so, they can arrange a referral to a sleep physician or sleep clinic for a proper assessment, which may include a sleep study. You can also complete this OSA risk assessment to see if you are at an increased risk of having obstructive sleep apnoea.

Alcohol and sleeping on your back typically increase the likelihood and incidence of snoring. Reducing or eliminating evening alcohol intake and trying to avoid sleeping on your back are strategies you can try immediately to reduce your snoring, while weight loss can be a longer-term strategy.

If you are at an increased risk of having OSA, or if your snoring is a social concern, we encourage speaking to your GP and arranging a referral to a sleep physician or sleep clinic for a proper assessment and treatment.

Central and Complex Sleep Apnoea ⬎

Central Sleep Apnoea (CSA) are pauses in breathing during sleep due to inadequate signalling from the brain to the respiratory muscles that drive breathing. This differs from obstructive sleep apnoea, where the proper signalling for breathing still occurs, but airway collapse/obstruction is responsible for the pauses/reduced breathing.

Central sleep apnoea is much less common than obstructive sleep apnoea and, depending on the clinical presentation or underlying cause, may require very different management. It can be relatively common to experience a couple of central apnoea episodes during sleep, especially during wake to sleep transitions, and sometimes no action is required. In other instances, central sleep apnoea can be caused by underlying medical conditions such as heart failure or stroke, so seeking professional advice for proper investigation will make sure you get the correct diagnosis and advice/management.

While snoring is more typically associated with obstructive sleep apnoea, it can still be present during central sleep apnoea. If you have been told you snore, or have pauses in breathing during sleep, we strongly encourage further investigations - especially if these may be associated with abrupt awakenings, feeling short of breath.

Complex Sleep Apnoea refers to people who are experiencing a combination of obstructive and central apnoea events, where incidences of both are clinically significant.

How do I find out if I have central or complex sleep apnoea?

Some other subtle signs of central or complex sleep apnoea can include mood changes, morning headaches, difficulty concentrating, excessive daytime sleepiness or difficulty staying asleep. Should you have any concerns, speaking to your GP about a referral to a sleep physician or sleep clinic for proper assessment and further investigation is strongly advised.

Obesity Hypoventilation Syndrome ⬎

Hypoventilation refers to shallow or under breathing resulting in sustained increases in blood carbon dioxide levels (hypercapnia) and reduced blood oxygen levels (hypoxia). This occurs due to poor lung expansion, restricting the amount of oxygen that can enter the lungs at any given time, resulting in shallower breaths.

Hypoventilation due to obesity is referred to as Obesity Hypoventilation Syndrome (OHS), where the excess weight adds pressure over the lungs preventing them from being able to fully expand, reducing their volume. It is typically more severe when lying down—especially on their back—as gravity adds further weight/pressure on the lungs, and therefore more likely during sleep. Hypoventilation also puts additional strain on the heart, and over time may lead to heart failure.

Obesity hypoventilation during sleep is often associated with obstructive sleep apnoea. Some signs of obesity hypoventilation include:

• Lethargy and tiredness
• Shortness of breath
• Daytime sleepiness
• Swelling of the legs
• Slow and shallow breathing
• Depression

How do I find out if I have obesity hypoventilation syndrome?

If you have a body mass index (BMI) over 35, especially if you are experiencing any of the signs and symptoms of obstructive sleep apnoea or obesity hypoventilation syndrome, we recommend a visit to your GP. If indicated, they can arrange a referral to a sleep physician or sleep clinic for more specialised assessment/management.

How is obesity hypoventilation syndrome managed?

Given obesity is what is causing the hypoventilation, sufficient weight loss should prevent the condition. If losing weight through traditional means has proven unsuccessful, various bariatric surgeries or medications to promote weight loss may be considered. Obesity hypoventilation in conjunction with obstructive sleep apnoea may require treatment using either CPAP (continuous positive airway pressure) or non-invasive ventilation (NIV) also known as Bi-PAP machines. These Bi-PAP machines allow for higher inspiratory pressures assisting with lung expansion, thus treating the hypoventilation while still providing adequate expiratory pressure to treat any airway obstruction that may also be occurring. In some instances, oxygen supplementation may also be required.

Insomnia ⬎

Insomnia refers to increased difficulty initiating sleep (Sleep Onset Insomnia SOI) or increased difficulty maintaining sleep throughout the night (Sleep Maintenance Insomnia SMI). If the insomnia is caused by an underlying sleep disorder, it may be referred to as 'secondary insomnia,' but if no other sleep disorders are present, then it may be referred to as 'primary insomnia.' Classifications of insomnia are evolving and changing as more research and developments in this complex area of sleep medicine occur.

How is insomnia diagnosed?

The label "insomnia" is often misused and incorrectly diagnosed. If your symptoms have been occurring for more than a few weeks, referral to a qualified sleep physician or clinical psychologist who specialises in this aspect of sleep medicine is strongly advised.

How is insomnia managed?

Any underlying sleep disorders or external factors that may be contributing to the insomnia will typically be treated before addressing the insomnia itself.

Implementing and maintaining healthy sleep practices (sleep hygiene) will often be the first and simplest step in addressing insomnia, but should more specialised treatment be required, the gold standard approach is applying cognitive behavioural therapy techniques for insomnia (CBTi). Some of the behavioural components of CBTi may be implemented by your sleep physician. Should you require the cognitive components of CBTi, referral to a clinical psychologist who specialises in this aspect of sleep medicine may be indicated. Somnocare works closely with Sleep Matters for patients who may require more specialised CBTi programs conducted by trained clinical psychologists.

Depending on your clinical presentation, sleeping medications, light therapy, or subscription melatonin may also be beneficial, but should only be administered under the supervision of your sleep physician.

Insomnia is complex and varies considerably between patients. To make sure you get the best possible management and advice, we strongly recommend a referral to a qualified sleep physician.

Circadian Rhythm and Shift Work Sleep Disorders ⬎

We each have an internal body clock that oversees the timing of sleep. As a diurnal species we have evolved to be awake during the day, and asleep during the night (continuously resynchronising our internal body clock to the external day night cycle through exposure to the sun). Due to a unique set of clock genes, some individuals can be predisposed to an earlier sleep pattern (larks), while others a later sleep pattern (owls). Certain lifestyle factors, including the timing of exposure to light, can have a further effect on our circadian rhythm, altering when we have a stronger or weaker drive for sleep. Circadian rhythm disorders occur when someone's sleep patterns misalign with typical school, work, or social requirements.

Exposure to light inhibits the accumulation of melatonin, a hormone that signals to your body it is night-time and to start preparing for sleep. Due to the invention of artificial light, and light-emitting technologies such as television and mobile phones, many of us are now suppressing the accumulation of melatonin in the evenings, thus suppressing the signalling to prepare for sleep. Shift workers are also required to work during the evening and overnight, forcing them to desynchronise from typical diurnal circadian rhythms.

How are these diagnosed?

Circadian rhythm disorders are typically assessed through sleep diaries/logs but can be more objectively measured using actigraphy. Actigraphy uses movement sensors (usually acquired via a watch worn around the wrist) to give long-term estimations of sleep/wake cycles. These assessments are typically done over a two-week period, though depending on shift rotations or other factors, longer monitoring periods may be required.

How are these managed?

Circadian rhythm disorders can often be managed by improving our sleep hygiene, which is essentially a set of healthy sleep rules/guidelines—but this isn’t always sufficient or possible, especially for shift-workers. The correct application and timing of light, in conjunction with supplemental melatonin, can also assist in shifting the body's internal clock. Incorrect timing, however, can further disrupt our circadian rhythm. Speaking to your sleep physician to ensure the correct prescription for light therapy and/or melatonin supplementation is strongly advised. These strategies can also be helpful for people frequently travelling across time zones.

Research has shown that certain strategies associated with cognitive behavioural therapy for insomnia (CBTi) can also be helpful in the management of circadian rhythm disorders.

Narcolepsy ⬎

Narcolepsy is a rare neurological disorder estimated to affect ~1 in 2000 people, characterised by sudden attacks of drowsiness during the day. Depending on the severity of these attacks, sufferers may not be able to resist falling asleep, often at inappropriate times, putting them at increased risk of motor vehicle accidents and injury.

Narcolepsy is typically associated with increased night-time disruption and awakenings with difficulty returning to sleep, and can therefore cause or exacerbate insomnia. Other characteristics of narcolepsy can include temporary sleep paralysis and vivid (and often frightening) nocturnal hallucinations during wake to sleep (hypnagogic), and sleep to wake (hypnopompic) transitions.

Some sufferers of narcolepsy can also experience cataplexy, defined by the sudden loss of voluntary muscle tone often triggered by heightened emotions (laughter/joy/sadness/anger) that can be quite specific and unique to the individual. These cataplectic episodes can range from being quite short and mild (and may even go undetected), to quite extreme resulting in the inability to move or talk for several minutes.

Excessive daytime sleepiness is generally the first symptom of narcolepsy, with other symptoms manifesting over several years. For this reason, it can go undiagnosed with sufferers believing they are experiencing multiple different disorders.

How is narcolepsy diagnosed?

Narcolepsy is typically diagnosed after taking a comprehensive clinical and family history, in conjunction with an overnight attended PSG sleep study followed by a daytime (MSLT) sleep study the next day. Testing hypocretin levels can also assist in the diagnosis.

How is narcolepsy managed?

Practicing good sleep hygiene, (in particular adopting a regular sleeping pattern) and, in some individuals, implementing regular planned napping opportunities during the day can be beneficial. Depending on the clinical presentation, medications may be required.

Narcolepsy is a complex disorder that should be diagnosed and managed by a sleep physician. If you are experiencing any signs or symptoms suggestive of narcolepsy, a GP referral to a sleep physician is strongly advised.

Restless Legs Syndrome (RLS) ⬎

Restless Legs Syndrome (RLS) is characterised by an irresistible/compelling urge to move your legs due to an uncomfortable sensation. Typical descriptions of the sensation are an unpleasant tingling, or feeling like spiders are crawling up the limbs. In more severe cases, these sensations can also occur in the arms. RLS primarily occurs at rest, and therefore more likely at night-time leading up to sleep. Moving the legs will provide some immediate relief, but the sensation returns shortly after, and sufferers can have difficulty initiating and maintaining sleep as a result. People with RLS often experience limb twitches/jerks during sleep as well (Periodic Limb Movement Disorder) that can result in brief awakenings or arousals from sleep and lead to daytime fatigue.

How is RLS diagnosed?

If you are experiencing symptoms of RLS, or been told you jerk/twitch your legs frequently during the night, we suggest speaking to your GP about a referral to a sleep specialist for a proper assessment. RLS is typically diagnosed based on your clinical presentation, in addition to questionnaires like the one linked below. A sleep study may also be recommended to investigate periodic limb movement disorder, which could be occurring in addition to RLS.

You can click the link below to download a PDF of the Restless Legs Syndrome Rating Scale.

• Restless Legs Syndrome Rating Scale

How is RLS managed?

RLS may be occurring due to an underlying medical issue or certain medications. Your doctor will likely refer you for a blood test including an assessment of iron levels. Low iron can cause or exacerbate RLS, and treatment may be as simple as increasing your iron intake. Magnesium supplementation can also help relieve symptoms, while prescription medications may be required in more severe cases.

If the RLS is caused by something more complex, such as damage to the nerves in the hands or feet, or a spinal cord injury, more specialised advice would be required.

To make sure you get the correct advice and management plan for your condition, speaking to your GP about a referral to a sleep specialist is advised.

Periodic Limb Movement Disorder (PLMD) ⬎

Periodic Limb Movement Disorder (PLMD) is a neurological disorder characterised by periodic, repetitive twitching or jerking of the limbs, more common in the legs but can also occur in the arms. These movements can occur every 5-90 seconds, but more commonly every 20-40 seconds, for spans of up to an hour. These movements can increase sleep fragmentation/disturbance that can lead to increased daytime sleepiness, and sufferers may mistakenly believe they have insomnia.

PLMD may also be associated with RLS described in the section above.

How is PLMD diagnosed?

PLMD can be formally diagnosed based on an attended or home-based PSG sleep study. An attended laboratory sleep study is the preferred investigation, as video monitoring can assist in capturing the exact nature of the movements occurring.

How is PLMD managed?

Like restless legs syndrome, periodic limb movement disorder can be caused by another medical condition, or appear on its own. As a result, determining the cause is required before a treatment/management plan is implemented. If the cause is due to an underlying medical condition such as low iron, treating this may resolve the PLMD. Magnesium supplementation can help relieve symptoms and prescription medication may also be required, but should only be taken as prescribed by your doctor after a suitable risk assessment has been performed.

If you believe you are suffering from RLS or PLMD, we recommend speaking to your GP who may arrange a referral to a sleep specialist.

Parasomnias ⬎

Perhaps the most complex and fascinating group of sleep disorders, parasomnias are sleep disorders that involve unusual, and typically undesirable, events or experiences that occur during sleep. These may include abnormal movements, talking, expressing emotions, and sometimes more bizarre behaviours like eating or sexual displays. Parasomnias can be broken down into REM parasomnias (parasomnias that occur during rapid eye movement [REM] sleep), non-REM Parasomnias (parasomnias that occur during non-rapid eye movement sleep) and other parasomnias (parasomnias that may occur during sleep-wake transitions or aren't exclusive to either REM or NREM sleep).

Examples of non-REM parasomnias include:

• Sleep or night terrors
• Sleep walking (also known as somnambulism)
• Confusional arousals
• Sleep eating

Examples of REM parasomnias include:

• Nightmares
• Sleep paralysis
• REM behaviour disorder

Examples of other parasomnias include:

• Sleep hallucinations
• Sleep Enuresis (bed wetting)
• Sexomnias
• Exploding head syndrome (loud imaginary noise as you fall asleep)
• Catathrenia (sleep related groaning)

Depending on the frequency and how troubling the parasomnias are will determine whether any action or treatment is required.

How are parasomnias diagnosed?

Parasomnias can be diagnosed by a sleep physician after taking a proper medical history from the patient about their sleep behaviours. An attended laboratory based polysomnographic (PSG) sleep study with video monitoring may also be indicated.

How are parasomnias managed?

Correctly identifying and diagnosing the type of parasomnia being experienced will be the first step.

Parasomnias are typically triggered by something that briefly arouses or wakes the patient, putting them in the transitional state between sleep and wake. Fun fact: the occurrences of parasomnias reported by people living within earshot of Big Ben in London are abnormally high.

Sometimes treating or removing the underlying cause(s) of these arousals can reduce the incidences of parasomnias. Improving sleep hygiene can also play a role and medications may also be prescribed depending on the clinical presentation.

Given the complexity of parasomnias, speaking to your GP about a referral to a qualified sleep physician to ensure the accurate diagnoses and best management plan is strongly advised.