Hypersomnia: 'My doctor thought I was on drugs'

People think I'm joking when I say that I can sleep through multiple alarm clocks blaring at top volume for two hours or more, or they ask why don't I just set my alarm for the time I plan to get up. But it's not that simple. Waking up and getting out of bed is the most difficult thing I do each day. I am 27, but I rely on my mother calling me every morning. By the time I become aware of what is going on around me, she may have rung 10 times or more. Sometimes, in a state of what's known as sleep drunkenness, I answer and mumble nonsense into the receiver before hanging up.

I realised that I might be suffering from a sleep disorder in 2002. I was 21 and living in university halls. I had dozed off around 3pm and, when I awoke an hour or so later, the building was deserted. I later discovered everyone had been evacuated due to a fire alert. When I asked my friends why they hadn't woken me, they told me they had banged on the door for ages: "We thought you couldn't possibly be in. There's no way anybody could have slept through all of that noise." But I had.

After that, people started asking me if I had narcolepsy. I looked it up and recognised many of the symptoms, from excessive daytime sleepiness and extremely vivid dreams to poor short-term memory. But the doctor I initially visited lectured me on the dangers of illegal drugs, ignoring my protests that I didn't take them, and handed me a prescription for tranquillisers, which I ripped up as soon as I left the surgery.

I slept deeply as a child. Chronic drowsiness hit when I reached adolescence – I had trouble waking up, was often late for school and sometimes fell asleep during lessons. My concentration levels were poor and I had no energy. My GP diagnosed clinical depression when I was in my late teens and, when I mentioned that I slept for up to 17 hours at a time, entered "hypersomnia" in my medical records, simply meaning I slept a lot. It was assumed my constant tiredness was caused by depression, but I now believe it was the other way around.

I am now freelance but when I was employed full-time I found stuffy offices torturous, kept a desk fan on permanently to keep me awake and sometimes had to call in sick, simply because I was too tired to go to work. I gave up learning to drive after dozing at the wheel, dropped off during social gatherings and on one occasion had valuable items stolen while sleeping on a bus. I was always tired, I rarely woke up naturally and I never felt refreshed from sleep. My fiancé became exasperated at having to wake me up every morning, and I believe my sleep problems were a significant factor in the breakdown of our seven-year relationship. He had become my personal alarm clock, while I was frequently too tired to have sex.

I saw several different doctors, all of whom were reluctant to refer me to a specialist. I was repeatedly told I must have poor "sleep hygiene" (or habits), and needed to try harder to get up. Without the confidence or energy to argue, I was unable to convince them otherwise. There was a glimmer of hope when one doctor referred me to a sleep clinic, but when I arrived, I was asked: "So, you think you have sleep apnoea?" When I explained that I thought I had narcolepsy, they said they couldn't help and sent me away.

After that, I tried to manage my symptoms with copious amounts of caffeine. Sometimes the pressure of trying to stay awake all day, every day would catch up with me and I would crash at 7pm. I was worried about the future. What if I wanted to have children? Would I be able to cope?

Earlier this year, I visited one more doctor's surgery and begged for help. The nurse practitioner I saw agreed that I had symptoms of narcolepsy or a related disorder and, following routine blood tests to eliminate any other possible causes, referred me to a specialist sleep unit. I was asked to fill in a sleep diary and an Epworth Sleepiness Scale, a questionnaire that measures daytime sleepiness (I scored 21 out of a possible 24). I was then given a pulse oximeter to wear on my finger during the night, to determine whether I might be suffering from sleep apnoea. When the oximeter results came back normal, my file was marked "narcolepsy?" and I was booked in for the standard diagnostic tests: a polysomnogram and Multiple Sleep Latency Test.

For the polysomnogram, I stayed in a special bedroom in the sleep unit and was observed from an adjoining room throughout the night. Electrodes were glued to my head, face and body to record brainwaves, muscle activity and eye movements, and a microphone and camera monitored exactly what happened while I slept.

The Multiple Sleep Latency Test, which consists of a series of scheduled naps, was performed the next day. After staying awake for two hours I was asked to get into bed and given a 20-minute period in which to go to sleep. This process was repeated every two hours throughout the day. While the same measurements taken during the polysomnogram were recorded, another purpose was to time how long it took me to fall asleep. I thought it would be difficult to keep falling asleep in a strange place with people observing, but instead found it almost impossible to stay awake.

In my follow-up appointment, the consultant physician explained that I had not experienced excessive Rapid Eye Movement (REM) sleep during the night, and I had not gone into REM during any of the short daytime naps, "which means you don't have true narcolepsy, but there is hard medical evidence that you have a sleep disorder". He explained that I had fallen asleep within five minutes during each of my daytime naps, which should not have been possible after a full night's sleep, and diagnosed idiopathic hypersomnia (which means excessive sleepiness without a known cause).

I have been prescribed Modafinil, a stimulant that assists with daytime wakefulness that is also used to treat narcolepsy, but it could be a long time before I find the exact treatment plan that works. And if I ever want to have children, I will need to stop taking my medication.

I believe that I am fortunate, though. My symptoms are at least manageable – some sufferers I have made contact with through online support groups can't function normally or hold down jobs without medication. I just hope that waking up naturally will eventually become the norm instead of a novelty, and that the time will come when I no longer feel that I am sleeping my life away.

Hypersomnia– the facts

Idiopathic hypersomnia is believed to affect one in 20,000 otherwise healthy adults. Some studies estimate this figure at one in 25,000.

It has also been referred to as essential hypersomnolence, idiopathic central nervous system hypersomnia or non-REM narcolepsy.

"There are diseases causing sleepiness that we recognise and can define, and there are sleepy people left over," says Dr Andrew Cummin, director of the Imperial College Healthcare Sleep Centre. "Idiopathic hypersomnia is a diagnosis of exclusion. It is an ill-defined and ill-understood disorder."

Symptoms include excessive daytime sleepiness over a period of more than three months, laborious wakening and prolonged grogginess, and unrefreshing naps.

Idiopathic hypersomnia is incurable but can be managed with stimulant drugs.

"There is no apparent cause," says Professor Jim Horne, of the Sleep Research Centre at Loughborough University. "It usually begins in early adulthood and is long-lasting, although about 25 per cent can eventually improve. It can be hereditary and remains a medical mystery."

Additional sources: NHS Direct, Journal of Sleep and Sleep Disorders Research, Clinicians' Guide to Sleep Medicine

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