A lot has been researched and written about one of the most precious physiological phenomenon—‘sleep’, meant for the ultimate physical and emotional regeneration of the body. It is believed that humans spend one-third of their lifespan sleeping. Having said that, almost everybody has experienced some trouble while falling asleep at some point in their lives.
While disturbed or fragmented sleep patterns can lead to overall fatigue of the body, there is also a lesser-known condition involving excessive sleep known as Narcolepsy. It is often mistaken by Hypersomnia, which also results in excessive sleeping. While patients dealing with Hypersomnia complain about not getting enough sleep resulting in lethargy, Narcolepsy is a chronic, neurological disorder that affects the control of sleep and wakefulness. With this condition, the urge to sleep comes calling without prior warning. Patients may even fall asleep while talking or driving. We attempt to spread awareness about this sleep disorder for an improved quality of life.
CAUSES The exact cause of Narcolepsy is still unknown, and it is usually regarded as an autoimmune disease leading to the deficiency of a neurochemical called Hypocretin that regulates signalling in the brain to stay awake. People with Type 1 Narcolepsy, have low levels of this hormone in their bodies.
SYMPTOMS One of the predominant symptoms of Narcolepsy is Excessive Daytime Sleepiness (EDS), which leads to a tendency of falling asleep at regular intervals spanning the day. This sleep pattern is also referred to as sleep attacks. EDS can further lead to decreased concentration, low energy, poor memory, fatigue and depression.
Patients may also experience additional symptoms like hypnagogic hallucinations, muscle weakness or cataplexy, sleep paralysis and automatic behaviours. While hallucinations can be extremely vivid, it can be also frightening that leads to sensory hallucinations. It could further involve abnormal Rapid Eye Movements (REM) which is usually caused in a state of wakefulness and dreaming.
Cataplexy or sudden muscle weakness affects the face, neck, and knees. Some people may experience only mild weakness, such as head or jaw drop, while others can collapse to the ground. These episodes are often triggered by strong emotions, such as surprise, laughter, or anger.
Sleep paralysis is a brief inability to move or speak while falling asleep or waking up. These episodes can last from a few seconds to several minutes. After the episode ends, people rapidly recover their full capacity to move and speak.
Automatic behaviours can also occur where people may fall asleep momentarily in the middle of any activity, such as driving. They tend to continue performing the activity in a subconscious state.
DIAGNOSIS Physicians usually begin the diagnosis procedure by asking for a detailed sleep history. As a part of the drill, the patient will be asked to fill out the Epworth Sleepiness Scale, which uses a series of short questions to gauge the degree of sleepiness. It is also mandatory to keep a tab on the sleep records which includes monitoring and recording sleep patterns for a week or two. It helps the doctor to compare how the patient’s sleep pattern and alertness are related. Often, in addition to this sleep log, the doctor advises wearing a wristwatch-like a device called actigraph which measures periods of activity and rest.
Along with sleep logs, there are two types of tests recommended by the doctors—Polysomnography and Multiple Sleep Latency Test. Polysomnography makes use of electrodes placed on the patient's scalp to measure a variety of signals during sleep. This test is conducted at medical facilities where the patient is required to spend one night. It measures the electrical activity of the brain (electroencephalogram), heart (electrocardiogram), the movement of muscles (electromyogram), eyes (electrooculogram), and breathing.
Multiple Sleep Latency Test measures how long it takes the patient to fall asleep during the day. Doctors observe sleep patterns. Patients suffering from Narcolepsy fall asleep easily and enter into REM sleep quickly.
TREATMENT There is no permanent cure for Narcolepsy but medication and lifestyle adjustments can help in managing the symptoms. Treatments involve both non-pharmacologic and pharmacologic components. While sleep hygiene is of utmost importance, doctors also stress upon physical exercise and a healthy diet. Patients usually improve if they maintain a regular sleep schedule of seven to eight hours per night along with naps during the day time. Pharmacologic treatment of Narcolepsy involves the use of central nervous system (CNS) stimulants such as methylphenidate, modafinil, dextroamphetamine sulfate, solriamfetol, to name a few. These medications are known to reduce daytime sleepiness and improve the symptoms in 65 to 85 per cent of patients.