MORE than half of patients with “clinically relevant” obstructive sleep apnoea (OSA) may miss out on further assessment under new Medicare criteria enabling GPs to directly refer patients for sleep studies, say researchers in this week’s MJA.

The researchers found that the combination of apnoea screening questionnaires – the Berlin (BQ), STOP-Bang and OSA-50 – with the Epworth sleepiness scale (ESS) was useful for identifying patients requiring further investigation for OSA, but missed more than half of those with “clinically relevant OSA”.

In November 2018, new Medicare criteria were introduced allowing GPs to directly refer eligible patients for sleep studies, if they had positive BQ results in at least two categories, an OSA-50 score of 5 or more, or a STOP-Bang score of at least 4, together with an ESS score of 8 or more.

The MJA authors evaluated 424 patients enrolled in the Tasmanian Longitudinal Health Study. They found that combining the screening questionnaires with the ESS resulted in high specificity (94–96%), but sensitivity was low at 36–51%.

Clinically relevant OSA was defined as moderate to severe OSA (15 or more oxygen desaturation events per hour) or mild OSA (5–14 desaturation events per hour) plus excessive daytime sleepiness.

The researchers said more work was needed to better identify patients with clinically relevant OSA who could benefit from treatment, and a STOP-Bang/ESS-based decision support tool, described in their article, may help GPs in identifying patients for assessment and referral.

But one expert said the researchers’ definition of “clinically relevant OSA” was casting the net too wide, contributing to their conclusion that approximately 50% of patients would be missed using the recently introduced MBS OSA screening guidelines.

Professor Doug McEvoy, a Practitioner Fellow of the National Health and Medical Research Council at the Adelaide Institute for Sleep Health at Flinders University, said there was a lot of debate about the patients with sleep apnoea who benefited from treatment.

“The evidence is very strong that people who are sleepy, and have associated quality of life or mood disturbance, benefit from continuous positive airway pressure (CPAP) therapy,” he said.

Also, patients with resistant hypertension have been shown to benefit from treatment, Professor McEvoy said.

But, he said, despite clinical guidelines recommending treatment to lower cardiovascular and metabolic risk in non-sleepy patients with more than 15 obstructive breathing events per hour, the evidence did not support this.

“If [people] are not sleepy, recent randomised controlled trials have cast considerable doubt on the commonly held belief they will benefit from CPAP [continuous positive airway pressure] treatment,” said Professor McEvoy, pointing to two recent articles he authored in European respiratory journals (here, and here).

Professor McEvoy was supportive of the current Medicare criteria.

“The new Medicare requirement says patients suspected of having OSA need to have at least moderate to severe sleepiness to warrant an investigation in the first place, and I would agree with that. I think that is where the benefit lies for treatment,” Professor McEvoy said.

However, Professor David Hillman, Clinical Professor at the University of Western Australia’s Centre for Sleep Science, said the Medicare referral criteria were not satisfactory at present and required further thought.

“They risk compounding underdiagnosis of an already significantly underdiagnosed problem.  However, if the astute GP remains concerned about the possibility of OSA despite the patient not reaching these thresholds for direct referral for sleep study, she or he can still refer the patient for a sleep specialist opinion,” Professor Hillman told InSight+.

He said questionnaire-based tools were inherently limited, although there may be “marginal benefit” in further tweaking them.

“Patients with highly suggestive, problematic symptoms need a diagnostic test – in this case, a sleep study – and simple, low-cost options should be available in this regard,” said Professor Hillman, who says funding level low-cost level 3 and 4 sleep studies would help.

Professor Danny Eckert, Director of the Adelaide Institute for Sleep Health, said the MJA findings highlighted the need to be cautious of negative screening results, particularly when common symptoms or comorbid disease were present.

“While the current study confirms that a positive screening result with the newly implemented tools for GPs to recommend people for sleep studies for people with suspected OSA performs quite well, the ability to rule out clinically significant OSA with a negative screening result using recommended cut-offs is inadequate,” he said.

“This is a problem, as untreated OSA can have a deleterious effect on health, wellbeing, productivity and safety not only for the individual but, as highlighted in the recent Parliamentary Inquiry into sleep health awareness, society more broadly.”

Professor Eckert said missing clinically important OSA in people with comorbid disease may be especially concerning because OSA may be an important treatable modifier of not only the consequences of OSA but potentially for the comorbid disease as well.

Professor Eckert said the MJA authors’ decision support tool could help to improve diagnostic accuracy.

“While this proposed approach requires further investigation and validation, it has considerable potential and should be pursued,” he said.

Professor Eckert said GPs could also tap into resources prepared by the Australasian Sleep Association.

5 thoughts on “Sleep apnoea: new Medicare criteria missing cases

  1. Anonymous says:

    Why can the medical profession not get over the fact that money and cost is not the “be all, end all” of diagnostics especially in the areas of O.S.A and Diabetes. these two medical icons go hand in hand with each other. Since this rotten government placed a charge of $500.00 plus for an overnight sleep study no wonder the patients are turning away from the safety aspect of a sleep study and the benefits that are derived from it.
    Can the medical profession not see that this costing affects the low to middle socio-economic people whose jobs may be long distance, statewide or local drivers also firies, nurses, doctors, teachers, police and all other industries that cover shift work or long working hours.
    Look overseas where the advances of sleep apnea and diabetes are well documented and far advanced to Australia’s struggling medical outputs. It is really time to catchup. There is a need to get out of our little corner and join the true professional medical breakthroughs that are happening in the global professional medical community.

  2. Professor John B Dixon says:

    None of the screening tests are reliable. Only symptomatic patients appear to NEED, or will patient continue with therapy. How did we sleep labs get funded in our major health service when the level of evidence for the efficacy therapy impacting hard outcomes was so low? But it seems they were essential!
    The evidence base for bariatric-metabolic surgery is excellent. Not only does it improve sleep quality dramatically (not related to OSA) but saves lives by substantially reducing obesity related complications, including diabetes, some cancer, and cardiovascular disease. Yet the 1.4 million Australians with clinically severe obesity (most of whom have OSA and poor sleep) have trivial accesses to effective surgical therapy.. And for those reliant on our public hospitals the level of care in negligent. Yet surgery is cost effective or dominant.

    It seems weight bias, stigma and discrimination sabotage logical health policy. Australians require effective health policy and access to effective care.

  3. Anonymous says:

    As a retired medical oncologist, I am dismayed by the lack of discussion on CENTRAL sleep apnoea which is a condition I have had for many years with significant disruption to my QOL. NOBODY talks about it. WHY? Are we too few to bother with?

  4. Anonymous says:

    It is annoying that Australians get so used to freebies. They want everything to be free without caring about who will fund it. It is alarming that people would sacrifice their health for a few dollars. I noticed that all the discussion revolving around who would fund the cost for screening, and the CPAP machines. Nobody has looked closely at comparing the cost of the treatment vs. benefits of better QOL, no loss of production, no injuries/road accidents due to lack of concentration on the road etc. Anyone with the condition knows very well that the benefits of the treatment far exceed its cost. Considering to spend over $1000 for the CPAP machine would bring one’s happiness, less likely to have an accident on the road to work and back home, and being awake most of the day, then one would choose to spend. I have seen a simple CPAP machine (without any technology to record, analyse patients’ sleeping patterns) cost under $1000 which lasts for more than 10 years and is still going. The treatment is for one’s benefit after all so please stop arguing around and pay for treatment yourself sooner rather than later?

  5. Matt says:

    here’s something on the cost for people from the recent Australian government enquiry:

    “The SHF stated that the annual cost of CPAP therapy is approximately $550 per person, but that if societal costs such as productivity are considered CPAP therapy ‘actually saves the country $440 per person treated.
    Associate Professor Mansfield provided a slightly higher figure for the benefit to society, stating that treating OSA with CPAP provides a ‘net cost saving to society of $857 per person treated.”

    Bit of a no brainer. If it saves the country money, improves peoples lives and health and reduces car accidents, then where are the objections

Leave a Reply

Your email address will not be published.