When Alan Bevan applied to be a driver for Transport Canberra, he considered himself a good sleeper.
He would be out like a light as the head hit the pillow; rarely woke up in the night and barely snored.
Mr Bevan was made to undergo a sleep study before he could get a heavy vehicle licence.
After being covered in nodes to measure his oxygen levels and sleep patterns, he was told he had obstructive sleep apnoea.
Sleep apnoea affects more than 1 million Australians, Professor Danny Eckert of Flinders University said.
In an episode, a person's airways closes or narrows enough to restrict oxygen until they wake up and start breathing again.
They typically do not notice they have woken up.
Dr Eckert said in severe cases an event would last 30 seconds on average, and could happen 100 or more times an hour.
"Not surprisingly [it] leaves people feeling pretty rotten the next day," he said.
"[Sleep apnoea] is associated with adverse effects for pretty much every organ in your body."
It is associated with heart disease, type 2 diabetes, stroke and car accidents.
Symptoms include morning headaches, tiredness and snoring.
It is more likely to affect men and older people. The gender gap tends to narrow when women hit perimenopause and menopause.
Men may be more impacted because of the anatomy of their throat, Dr Eckert said.
Sleep apnoea is also associated with excess weight.
"Men tend to store it on their belly and when they go off to sleep, that pushes down your abdomen [and] decreases lung volume," he said.
"Half the people that get sleep apnoea are not obese. Skinny people get this, too, but there's a good relationship between sleep apnoea severity and weight loss."
Continuous positive airway pressure (CPAP) is the first treatment option recommended for people with sleep apnoea, Dr Eckert said.
Mr Bevan, who has mild sleep apnoea, was initially sceptical about his diagnosis.
He eventually spoke to Taylaar Hart at CPAP Canberra Direct, hired a machine and tried a number of different masks.
Mr Bevan also saw Woden-based sleep physician Daniel Wang, who he said "explained so much to me and in such a way that I could understand it".
"I didn't feel I had a problem," Mr Bevan said.
"[But now] I've got a lot more energy than I did beforehand.
"I breathe better at night now, I'm not going to suffocate in my sleep like Taylaar was worried I might."
Sleep apnoea symptoms
- Poor quality sleep
- Daytime sleepiness and fatigue
- Dry mouth and headaches in the morning
- Poor concentration, poor memory, slow reaction times
- Irritability and mood changes
- Impotence and reduced sex drive
- Need to go to the toilet frequently at night
- Source: Victorian government
Ms Hart advises clients to hire a machine before buying one, admitting not everyone can tolerate it.
She has more than 30 types of masks.
"We try to push everyone onto rentals because not everyone can tolerate a machine. It's better that you waste a couple hundred than a couple of thousand," Ms Hart said.
"It is something foreign on your face and it is forcing you to breathe, it is a weird sensation."
Ms Hart said the worst case she had seen was a three-year-old boy with 142 episodes an hour, and oxygen levels as low as 67.
A normal oxygen level is 95 per cent or higher, according to the Royal Australian College of General Practitioners.
Ms Hart has clients ranging from two to 96. She said young children usually had pre-existing conditions which required a CPAP machine.
The ACT has stringent medical requirements for heavy vehicle drivers.
Mr Bevan's sleep apnoea episodes have reduced enough for him to be issued a heavy rigid vehicle licence.
He starts bus driver training next month.
"I'm ecstatic. I'm over the moon," Mr Bevan said.
"I'm really loving the fact that I can now get in a bus and I can drive, and even if I don't get a job, I can hire a bus and I can take my friends."