Dead of the night

A serious sleep disorder could be lethal. Yet getting diagnosis and treatment can take years, JAN CORBETT finds.

Unlike most people who sleep alongside someone with sleep apnoea, Roy McKone's partner did not move into the next room when the loud snoring, snorting and gasping got too much, but insisted he see the specialists at Green Lane Hospital's sleep clinic.

Looking back, the computer company executive realised he had many of the typical apnoea symptoms - feeling tired during the day, trouble staying awake through company presentations, loss of short-term memory and poor concentration.

Stanford University Professor William Dement describes sleep apnoea as the "most undiagnosed deadly problem in medicine."

He believes that each year an estimated 38,000 fatal heart attacks and strokes in the United States are caused by sleep apnoea, and he urges anyone with high blood pressure to ask themselves if they feel tired in the daytime.

The terrible thing for apnoea sufferers is that they believe they are getting a good night's sleep when in fact they are barely sleeping at all. Instead, their airway is constantly collapsing, preventing them from breathing. Their oxygen-deprived and panicked brain fights to snap them back into consciousness so that breathing can resume. This pattern can be repeated hundreds of times each night.

Snoring in itself is not necessarily a problem, although the research debate is whether snoring is the beginning of a sleep apnoea problem.

New Zealanders with high blood pressure who feel tired during the day may have trouble finding out if they indeed suffer from apnoea and then having it treated. Auckland has two sleep clinics to make the diagnosis - a private one at Mercy Hospital and a public one at Green Lane.

The Green Lane clinic is funded to see only 350 of the 1000 people referred to it each year with suspected sleep apnoea. The waiting list is up to seven years, so unless your case is so bad you are falling asleep at the wheel, you may never be properly diagnosed or treated.

Clinic head Dr Ken Whyte says men are more susceptible to apnoea than women and testosterone is thought to play a role. All of us probably stop breathing in our sleep at some time, especially if we've been drinking alcohol.

But there are other factors, too, such as a small jaw and throat, having suffered a nasal obstruction like tonsilitis in childhood and being older, because an old throat collapses more readily.

Weight and thickness of neck are also risk factors showing up particularly in this country, where Maori and Pacific Island men dominate the numbers attending sleep clinics and are highly represented in those dying from heart attack, stroke and car crash - the side-effects of sleep apnoea.

Which is part of the reason a study on the incidence of apnoea is being run out of the Wellington School of Medicine in conjunction with the Eru Pomare Maori Health Research Centre.

The 400 participants are monitored in their homes with equipment that measures heart rate, snoring levels, blood oxygen and body position while they're sleeping to indicate if they have apnoea.

The question is whether Maori have other particular features making them vulnerable to sleep disorders and whether they are having the condition recognised and treated early enough.

A specialist sleep researcher at the Wellington School of Medicine, Dr Philippa Gander, says that at the end of the project they hope to be able to provide doctors with better information about the incidence of sleep disorders among New Zealanders and to improve the availability of treatment to people who need it.

The standard treatment for apnoea is to sleep with a continuous air- pressure machine (CPAP) that forces air down the windpipe. In this country you have to stop breathing 20 times every hour to qualify for publicly funded CPAP treatment.

Roy McKone did not take well to CPAP, so he was referred to an ear, nose the throat specialist who recommended an operation to prevent the airway collapsing during sleep.

"It has helped enormously," says McKone. "Since the operation the symptoms have gone."

Apnoea is only one of a growing list of sleep disorders which now number more than 80. Arguably more common, affecting about 10 per cent of the population, is a condition known as periodic limb movement.

It means your legs thrash around so violently when you are asleep that it rouses but never fully wakens you. It will be accompanied by restless leg syndrome - an uncontrollable urge to move your limbs while you are awake.

Wellington sleep specialist Dr Alister Neill says periodic limb movement can be caused by anything from neurological disorders, renal failure, anaemia or antidepressants. He says it is easily treatable. Sometimes all that is required is reassurance that there is nothing seriously wrong.

Then there is narcolepsy which, according to Dr Neill, is woefully underdiagnosed in our community. It affects .06 per cent of us, making it twice as common as multiple sclerosis.

People with narcolepsy suffer from extreme daytime tiredness and muscle collapse, or cataplexy. They have extremely vivid dreams, or hallucinations, and tend to wake up feeling paralysed.

The cause is unknown but Dr Neill says research suggests there may be a genetic predisposition. The most important thing with narcolepsy, he says, is to have it diagnosed. It can be treated by planning to get adequate sleep, using stimulants or drugs to suppress REM sleep.

NEXT WEEK: How to get a decent night's sleep.

If you have a serious sleep problem, tell us your story.

E-mail: Jan Corbett

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