Dropping off to a disorder

By REBECCA WALSH health reporter

Falling asleep during university lectures as a teenager did not seem that unusual to Lisa Rollins.

But then she started falling asleep at work and while travelling on public transport. Her legs would give way whenever she told a particularly funny joke and every night she would suffer nightmares. Occasionally she would wake up unable to move.

The 32-year-old knew something was wrong.

"I would describe it to doctors without success. I was told I was experiencing an anxiety attack. I knew that wasn't the case, but I couldn't make my case to them."

While reading about a friend's diagnosis of sleep apnoea (when breathing stops briefly) on the internet, she discovered narcolepsy.

Narcolepsy is a sleep disorder where people fall asleep without wanting to.

Professor Clifford Saper, chairman of the neurology department at Beth Israel Deaconess Hospital and Harvard Medical School, told a sleep seminar in Auckland during the weekend that it tended to develop in a person's late teens or 20s, possibly as a result of an allergic response to a viral infection.

About two or three people for every 10,000 were thought to have it in varying degrees of severity.

Those with the condition would fall asleep without wanting to. Sometimes they would dream while still awake, almost like a hallucination, and many suffered from cataplexy.

"Someone might tell them a joke or they get angry and they literally become weak at the knees, lose all muscle strength and collapse like a little pile of jelly on the ground. It can last for about 10 minutes."

Professor Saper said it was believed that loss of a neurotransmitter in the brain, called orexin or hypocretin, caused the disorder. The neurotransmitter stabilised the "switching mechanisms" in the brain to keep people from falling asleep when they wanted to be awake.

Medication such as Ritalin, which is used to treat attention deficit hyperactivity disorder, helped control the symptoms.

Dr Ken Whyte, director Greenlane Hospital's Sleep Disordered Breathing Clinic, said narcolepsy was underdiagnosed - about 50 people in Auckland were being treated for it.

Narcolepsy could be difficult to diagnose as symptoms varied in severity and were often vague. If someone complained of constantly feeling tired GPs were often more likely to test for conditions such as anaemia.

People often had difficulty accessing services because of a lack of knowledge about the condition and resources, he said.

Ms Rollins moved to Wellington from America 4 1/2 years ago, and was diagnosed with narcolepsy at the Wellington Sleep Clinic.

She was reluctant to take medication but in February started using Modavigil, a new drug for narcolepsy. The result is less daytime sleepiness, better concentration, greater activity and more restful sleep.