diagnosing narcolepsy

Visit your local doctor

In order to make a determination of narcolepsy, your doctor will ask you for a complete medical and family history and may refer you to a sleep center for evaluation. You should keep a sleep diary as well as a record of your symptoms and their severity for at least a week or two. Bring this information with you when you visit your doctor. The important things to note in your sleep diary are how fast you fall asleep generally (obviously, you will need someone to help you with this!). However, if you fall asleep the minute to lie down, you will be aware of this yourself. For example, if you can’t get past the first paragraph in the book you are reading….. ALL THE TIME… etc. Note also how many times you doze off during the day and during what activities. A person with narcolepsy is capable of falling asleep while eating, in conversation, watching TV, travelling on a bus, train or driving! Your sleep episodes may only last a few seconds or can be longer. This information is invaluable as it is this often odd and bizarre sleep habits that set you apart from just being tired, overworked etc.

 Get a referral to visit a sleep consultant
In your sleep diary, describe your nighttime sleep. Do you dream a lot? Do you have nightmares or hallucinations? All of this information will help your doctor and don’t be afraid to insist that you would like to be referred to a sleep consultant. A huge obstacle in getting diagnosed and starting on a treatment plan for many people with narcolepsy is because of a lack of awareness of the condition by the medical profession and people being subsequently misdiagnosed.

The sleep study tests
If it is recommended by your consultant, that you should be tested the sleep study involves an overnight in hospital (The Mater Private) . Two tests in particular are considered essential in confirming a diagnosis of narcolepsy: the polysomnogram (PSG) and the multiple sleep latency test (MSLT). The PSG is an overnight test that takes continuous multiple measurements while a patient is asleep to document abnormalities in the sleep cycle. It records heart and respiratory rates, electrical activity in the brain through electroencephalography (EEG), and nerve activity in muscles through electromyography (EMG). A PSG can help reveal whether REM sleep occurs at abnormal times in the sleep cycle and can eliminate the possibility that an individual’s symptoms result from another condition.

The MSLT is performed during the day to measure a person’s tendency to fall asleep and to determine whether isolated elements of REM sleep intrude at inappropriate times during the waking hours. As part of the test, an individual is asked to take four or five short naps usually scheduled 2 hours apart over the course of a day. As the name suggests, the sleep latency test measures the amount of time it takes for a person to fall asleep. Because sleep latency periods are normally 10 minutes or longer, a latency period of 5 minutes or less is considered suggestive of narcolepsy. The MSLT also measures heart and respiratory rates, records nerve activity in muscles, and pinpoints the occurrence of abnormally timed REM episodes through EEG recordings. If a person enters REM sleep either at the beginning or within a few minutes of sleep onset during at least two of the scheduled naps, this is also considered a positive indication of narcolepsy.

It does seem that every case is different. Some people can have narcolepsy with cataplexy and others have just narcolepsy. People vary greatly in levels of symptoms, that being one of the reasons it is difficult to identify by GP’s. Following a review of the results of your sleep study your consultant will discuss treatment options with you. There is no cure, but with the correct medication, diet and lifestyle changes the condition can be managed.