Despite increased awareness of the respiratory-related condition, less than 10 per cent of sufferers have been diagnosed, writes Áine Kerr
Walking around like zombies and suffering excessive daytime sleepiness, irritability and lack of concentration characterise the daily routine of thousands of Irish people.
Falling asleep during the working day, suffering morning headaches and enduring increased heart rate, anxiety and depression are also symptomatic of obstructive sleep apnoea.
Some 5,000 people are known to suffer from this sleeping disorder in the Repulic, but as many as 100,000 could be suffering without diagnosis or treatment.
The respiratory-related condition, which occurs when the throat is sucked closed and narrowed during sleep, causes breathing to stop and the levels of oxygen in the blood to drop.
This may subsequently cause a reflex response which can force open the airway with a snort, gasping breaths or loud snoring.
Prof Walter McNicholas, director of respiratory, sleep and pulmonary function disorders at St Vincent's University Hospital, contends that sufferers repeatedly find sleep unrefreshing and experience varying levels of daytime sleepiness.
Sleep apnoea is considered "quite a large problem", as 4 per cent of adults are thought to suffer from the condition, equating to between 60,000 and 100,000 in Ireland. Fewer than one in 10 have been diagnosed and treated.
Despite increased awareness of the condition, sufficient resources are not available to specialists, according to Prof McNicholas.
"St Vincent's is the major referral centre. From the point of referral to diagnosis, there are waiting lists in excess of two years," he says. "It's extraordinary that we have such lengthy waiting lists and we are well behind international practice in this regard."
For an apnoea event to count as serious, it must last 10 seconds or more, while five or more episodes per hour are considered to be of clinical significance, according to Dan Smith, secretary of the Irish Sleep Apnoea Trust.
Smith was diagnosed with apnoea in 1994 and has since used a device called a continuous positive airway pressure (CPAP) machine to control the condition. This is a face mask that forces air into the nose and mouth and keeps the airway open.
Thousands of others however go through their lives unaware of their condition. Such undiagnosed apnoea sufferers have a greater risk of suffering stroke and are eight to 10 times more likely to be involved in road traffic accidents.
"I often wonder how many single vehicle crashes occur between 11pm and 4am due to sleep apnoea. In the UK, the traffic police have recorded that 20 per cent of all road traffic accidents are caused by sleepiness," says Smith.
In recognition of the seriousness of the condition, UK driving licence application forms require applicants to declare if they have a history of sleep apnoea.
Newly diagnosed licence holders must surrender their licence, which will usually be returned when a sleep consultant declares that the symptoms are under control.
Films such as My Own Private Idaho, in which the character played by River Phoenix suffers from narcolepsy and the fleeting urge to sleep, and the death of Reggie White, an American National Football League player who suffered from sleep apnoea, have succeeding in heightening awareness of sleeping disorders.
"Traditionally, the people diagnosed were the middle-aged and overweight type of person who were as such paying for the sins of the past.
"Now, you have skinny people and young people being diagnosed. Normally, people would be diagnosed from their 30s upwards. Now you have people being diagnosed at the age of 17," says Smith.
Most GPs will immediately refer a suspected sleep apnoea sufferer to a sleep consultant, who normally recommends a night in hospital undergoing a study known as a polysomnogram. However, Smith is critical of GPs who disregard the condition or prescribe sleeping tablets, which he says is "the worst thing that can be done".
He adds: "If you look at all the medicine courses which last for five years, [ the students] might get nothing or maybe an hour in total over the whole course on this sleep disorder. That is a fact."