Some readers will have seen the 1991 film My Own Private Idaho in which River Phoenix plays a narcoleptic street hustler. Narcolepsy is defined by the Collins English Dictionary as a rare condition characterised by sudden and uncontrollable episodes of deep sleep. The term narcolepsy is derived from the Greek, meaning "seized by somnolence". A succinct account of the condition is given in Medicine Weekly February 10th, 1999. The All-Ireland Narcolepsy Support Group welcomed a new drug called Provigil to Ireland to treat narcolepsy.
Sleep is an essential part of life, but the majority of us who have normal sleep patterns take it for granted. However, when occasionally some worry deprives us of a good sleep for a couple of nights in a row, the consequent feelings of irritability and lack of day-time concentration graphically illustrate the importance of sleep. It is therefore easy to appreciate the devastating effect that grossly abnormal sleep patterns can have on quality of life. Narcolepsy results from a malfunction of the brain's sleep/wake regulation system. The principal symptoms of the illness are excessive daytime sleepiness (EDS), cataplexy, and sleep paralysis. One does not have to express all the symptoms to suffer from narcolepsy, but EDS is present in all cases. The severity of the symptoms can vary from person to person.
EDS is the main symptom of narcolepsy and presents as uncontrollable and recurrent attacks of sleep throughout the day. It is the most disabling symptom and the most difficult to treat. The impulse to sleep is overpowering and attacks of sleep last up to 30 minutes.
EDS is different to ordinary sleepiness in that the individual can experience an attack of sleep at any time and during almost any circumstance. People with EDS can fall asleep in unusual circumstances, such as eating, holding a conversation, or walking. Obviously, this is extremely inconvenient, and also possibly dangerous. Up to 80 per cent of people with narcolepsy experience fluctuations in alertness lasting from a few seconds to several minutes, during which time they can perform irrational and potentially dangerous tasks, such as putting the electric iron in the refrigerator. They have no recollection of these tasks after the event.
About 70 per cent of people with narcolepsy develop cataplexy, sometimes many years after the onset of EDS symptoms. Cataplectic attacks involve a sudden decrease or loss of muscle tone affecting either the whole body or just certain muscles. Attacks may last from seconds up to 20 minutes. Sufferers experience a range of symptoms such as drooping arms, sagging jaw, and slurring or loss of speech. In extreme cases the individual may collapse. The attacks are triggered by strong emotion - excitement, anger, fear, and, most commonly, laughter. Sometimes the attack can be triggered by the anticipation of emotion, e.g., anticipation of the punch-line to a joke. Somewhere between a quarter and two-thirds of people with narcolepsy experience periods of sleep paralysis. This is inability to speak or move during the transition between sleeping and wakefulness. Also, 30 to 60 per cent of people with narcolepsy experience intense dreamlike imagery or sounds that are not real while falling asleep or awakening from sleep. These hallucinations differ from dreams because they occur when the sufferer is not fully asleep. Narcolepsy can affect anyone and can develop at any age, but it is common for symptoms to develop during adolescence. Six per cent of people with narcolepsy develop symptoms before the age of 10. The syndrome affects both men and women equally. About 150 people in Ireland have been diagnosed with narcolepsy, but it is estimated that many more people with narcolepsy (at least 1,500) are currently undiagnosed. The basic cause of narcolepsy is still unknown. Genetic predisposition may lead to the development of the condition and the immediate family of people with narcolepsy are considered to be at a slightly increased risk. Narcolepsy is not an epileptic or psychiatric disorder, but it may be misinterpreted as one.
Narcolepsy often has severe psychological consequences for sufferers. The extent of the disabling effects of the condition has been compared to those of epilepsy. Normal activities are disrupted by the inability to stay awake during daylight hours, causing problems at school, work, and in personal relationships. Many young people with narcolepsy suffer extreme embarrassment, have low self-esteem and a poor self-image. Many career options may have to be ruled out because of the condition.
Narcolepsy can lead to problems in interpersonal relationships. Sexual problems can also occur. Narcolepsy causes problems in social situations as sufferers fear the embarrassment of falling asleep in public. Sufferers are also more likely than average to develop depression and chronic anxiety. Many people with narcolepsy help themselves by adapting their lifestyle to cope with the condition. Altering eating patterns may help to ease symptoms and people with narcolepsy are advised to adopt a regular sleeping pattern at night. Scheduling naps during the day especially the afternoon, is often helpful. The All-Ireland Narcolepsy Support Group provides information and support to people with narcolepsy and their carers. Ms Sheila Farrell, who runs the group, can be contacted at 01-2895356.
Narcolepsy has been treated with drugs, principally amphetamines, however, there are unwanted side effects and patients can become dependent on these drugs. (William Reville is a Senior Lecturer in Biochemistry and Director of Microscopy at UCC.)