Home Sleep Studies in Australia: How Sleep Apnoea Is Diagnosed, and Whether CPAP Is Enough

Snoring, waking unrefreshed, or falling asleep in front of the television? Here is how a sleep study actually works in Australia, and an honest look at what CPAP does and does not fix.

Most people who suspect they have sleep apnoea put off doing anything about it, usually because they imagine a night in hospital covered in wires. In Australia that is no longer how it typically works. Most diagnoses now come from a study you do at home, in your own bed, and your GP can often refer you directly.

What obstructive sleep apnoea actually is

During sleep, the muscles that hold your upper airway open relax. In obstructive sleep apnoea, the airway narrows or closes completely for short periods. Oxygen levels dip, and your brain briefly rouses you to restore breathing. You will not remember any of it, but it can happen hundreds of times a night, which is why people with apnoea often feel exhausted despite spending eight hours in bed.

Severity is measured by the apnoea-hypopnoea index (AHI), the average number of breathing interruptions per hour of sleep. Broadly, 5 to 15 is mild, 15 to 30 is moderate, and above 30 is severe.

Signs it is worth investigating

•      Loud snoring, particularly with pauses or gasping that a partner notices

•      Waking unrefreshed no matter how long you slept

•      Daytime sleepiness, especially falling asleep watching television or feeling drowsy while driving (this last one is a BIG red flag).

•      Morning headaches, a dry mouth, or night-time reflux

•      Blood pressure that is difficult to control

•      Waking suddenly with a choking or gasping sensation

A partner noticing that you stop breathing is the single most useful piece of information you can bring to a GP appointment.

How sleep apnoea is diagnosed in Australia

Under Medicare there are two routes to a diagnostic sleep study. A sleep or respiratory physician can assess you directly and arrange one. Alternatively, and more commonly, your GP can refer you straight for a study once they have screened you with an approved questionnaire.

For that direct GP referral, you need to meet a specific threshold: a STOP-BANG score of 4 or more, an OSA-50 score of 5 or more, or a high-risk result on the Berlin Questionnaire, combined with an Epworth Sleepiness Scale score of 8 or more.¹ These are short questionnaires covering snoring, tiredness, observed pauses, blood pressure, neck circumference and how likely you are to doze off in everyday situations. Your GP can run through them in a standard appointment.

It is worth knowing that the Medicare item exists to confirm a diagnosis. Once you have been diagnosed, you are not eligible for a further diagnostic study, so it is worth having the first one done properly.

What a home sleep study involves

A home-based study is formally called an unattended or Level 2 study. You collect a small recording device from the clinic, or it is posted to you, and someone shows you how to fit the sensors. Typically, that means a band around the chest, a small clip or probe on a finger to measure oxygen, and a soft tube under the nose to record airflow.

You then sleep at home as normally as you can manage. The device records overnight, you return it, and a sleep physician reports the results. Compared with a laboratory study, it is considerably more comfortable, and you are sleeping in your usual environment rather than an unfamiliar bed. For straightforward suspected apnoea it gives the information needed to make a diagnosis.

Laboratory studies still have a place. They are used where the clinical picture is more complicated, where other sleep disorders are suspected, or where a home study has been inconclusive.

Does CPAP work?

CPAP, or continuous positive airway pressure, delivers gently pressurised air through a mask to hold the airway open. Mechanically it is very effective. In the largest trial conducted to date, CPAP reduced breathing interruptions from 29 per hour to fewer than 4.² For people who are sleepy during the day, the difference in how they feel can be substantial, and often shows up within a week or two.

The machines are not what they used to be

If your mental image is a noisy grey box the size of a briefcase, that image is around twenty years out of date. Current machines are roughly the size of a shoebox, and run at about 27 to 30 decibels, which is quieter than a whisper and generally quieter than the snoring they replace. Masks have shrunk considerably: alongside full-face masks there are nasal masks and nasal pillow designs that sit under the nose and leave most of your face clear. Most machines include a heated humidifier to stop your nose and throat drying out, ramp settings that start at a low pressure while you fall asleep, and an app that reports how well the therapy is working.

People who tried CPAP a decade ago and gave up are often surprised by current equipment. If that is you, it is worth another conversation with your sleep physician.

Why CPAP is still a band-aid

CPAP holds the airway open while you wear it. It does not change why the airway collapses in the first place, and the apnoea returns the first night you stop using it. That distinction matters more than it might sound.

In that same large trial, CPAP did not reduce heart attacks or strokes compared with usual care, despite clearly controlling the apnoea itself. Average use was 3.3 hours a night.² No treatment can work during the hours it is not worn, and part of the explanation for that result is simply that people were not using the machines for most of the night.

None of this is an argument against CPAP. If it has been prescribed for you, use it, and use it for as much of the night as you can manage. It is an argument for treating what sits underneath as well:

•      Weight, where it is a relevant factor

•      Alcohol and sedatives close to bedtime, both of which relax the airway

•      Nasal congestion, allergies or structural blockage, which make mask therapy harder to tolerate

•      Sleeping position, since apnoea is often worse on the back

•      Mandibular advancement splints, fitted by a dentist, which suit some people with mild to moderate apnoea

•      Surgical options, in selected cases

If the mask is uncomfortable or you are pulling it off in your sleep, tell your sleep physician rather than quietly giving up. Fit and pressure problems are usually solvable, and a machine used properly for six hours is worth far more than one used reluctantly for two.

Where osteopathy fits, and where it does not

Osteopathy does not treat sleep apnoea. We want to be clear about that, because there is no shortage of manual therapy marketing that implies otherwise. Apnoea is a medical condition that needs medical diagnosis and management.

What we do see is the overlap. People with apnoea often also have neck and shoulder pain, jaw clenching, or headaches, and poor sleep makes all of those harder to settle. If pain is part of what is disturbing your nights, that is something we can help with, and it sits alongside your medical care rather than replacing it. We have written separately about pain that wakes you at night and how to sleep better.

Where to start

Book a longer appointment with your GP and mention snoring, pauses in breathing, and daytime sleepiness specifically. Take your partner if they are the one who has noticed. Ask about a home sleep study.

Pain or stiffness disturbing your sleep? Our osteopaths at Grassroots Healthcare in Canungra can help. Book an assessment online or call 0422 071 200.

References

1. Australian Government Department of Health, MBS Online. Changes to diagnostic services for sleep disorders (fact sheet). https://www.mbsonline.gov.au/internet/mbsonline/publishing.nsf/Content/Factsheet-SleepDisorders

2. McEvoy RD, Antic NA, Heeley E, et al. CPAP for prevention of cardiovascular events in obstructive sleep apnea. N Engl J Med. 2016;375(10):919–931. https://doi.org/10.1056/NEJMoa1606599