For almost two decades, Philip Skeates woke up dog tired, even though he had just spent a good 12 hours in bed. He would get up for breakfast, then stagger back to bed until noon. By eight at night he was nodding off.

Eventually his wife persuaded him to seek medical help. Her husband, 39, was completely exhausted, and she was suffering too.

To the amazement of experts, he was diagnosed with one of the worst cases of sleep apnoea - a condition that causes the airways to close - that had ever been seen in Britain.

It meant that Skeates stopped breathing every 40 seconds or so during the night. He would briefly wake up, without properly regaining consciousness, and then fall back to sleep. And the process would begin over again.

Doctors estimated Skeates was only actually sleeping for a few seconds at a time, and for less than 15 minutes in total every night. "Every day I would get up feeling exhausted," he said. "I couldn't concentrate and I was ratty with my family. I couldn't understand it because I would fall asleep in my chair by 8pm and not get out of bed for 12 hours. But in fact I was hardly getting any sleep at all. It was miserable for me and it just wasn't fair on my family."

He finally visited his GP because his snoring - an effect of the condition - was so loud that his wife, Lisa, 40, a teaching assistant and their three children, were kept awake. She also became alarmed at how quiet and still her husband became in between the bouts of loud snoring.

Skeates was referred to the Great Western hospital near the family home in Swindon, Wiltshire, where his sleep was monitored and the results were startling.

Doctors found he stopped breathing 90 times an hour. "The doctors said it was one of the worst cases they had ever seen," he explained. "I was really only getting 14 minutes of sleep."

Happily, Skeates is now getting a good night's rest for the first time since the early nineties. The hospital arranged to have a continuous positive airway pressure machine installed at Skeates's home. It contains an oxygen mask and tube which he must wear while he sleeps. The equipment forces air into the lungs and keeps the airways clear.

His snoring stopped instantly and within weeks he was feeling refreshed after just seven hours of sleep. He has lost weight and is learning to love life again.

Skeates said: "This has changed my life. The very first night I had it I noticed a difference the next morning. Now I wake up in the morning feeling so much more refreshed."

Professor John Straddling, consultant chest physician at the Churchill hospital in Oxford, said there were around 300,000 sufferers of sleep apnoea in Britain though only about one in five is diagnosed.

He said: "Many GPs and primary care trusts are unwilling to diagnose sleep apnoea although it has a horrendous impact on these patients' lives. This affects us all. Undiagnosed patients cost the NHS a lot of money as they get older, and the condition affects us all in the form of road accidents."

Lisa Skeates said the cure had "reawakened" their marriage. "It's been wonderful. Phil is so much more energetic and cheerful. For 17 years the snoring got worse and worse until it was like sleeping next to a pneumatic drill. It was horrendous.

"At most, I would get a couple of hours sleep, and I'm a teacher so it was terrible. The children sleep upstairs and they could hear it through the floorboards. I tried earplugs and sometimes, when it was really bad, I would go and sleep on the sofa just to get a bit of rest.

"Now we have a laugh together again and we're also able to do things as a family which we never did before because he was always so tired. I've also been able to have a good night's sleep for the first time in years."

FAQ: Sleep apnoea

What is sleep apnoea?
It's a relatively common condition that occurs when breathing stops or gets shallow during sleep, with pauses lasting for 10 to 20 seconds or more

Who gets it?
According to the British Snoring & Sleep Apnoea Association, it occurs in around 4% of men but is very rare in women

What are the symptoms?
People with apnoea often do not know they have problems breathing at night. They tend to snore loudly (though not everyone who snores has sleep apnoea) and not feel rested when they wake

Are there different types?
The most common form is obstructive sleep apnoea, where not enough air flows into the lungs, causing blood oxygen to fall. When normal breathing returns, it usually starts again with a loud snort or choking sound. Another form is central sleep apnoea, a neurological condition that stops all breathing during sleep. A person with this form is normally woken by an automatic breathing reflex, so ends up getting very little sleep

How dangerous is it?
Besides tiredness, if left untreated, sleep apnoea can increase the risk of high blood pressure, heart attacks or stroke

Can it be cured?
In most cases, it can be treated with a device that keeps a person's airways open during the night using a flow of pressurised air into the throat. There are also drugs that can help. Milder cases can be treated with a slight change in lifestyle: avoiding alcohol or muscle relaxants can help. Losing weight and quitting smoking is also suggested. Sleeping at a 30-degree angle also seems to work in some cases