Narcolepsy or excessive sleep disorder is a neurological disorder which directly affects the sleep cycle in individuals. ‘Narcolepsy is not that common in India. For every 20 cases of insomnia, we get about 1-2 cases of narcolepsy,’ says Dr Sudhir Kumar, senior consultant neurologist.
The exact cause narcolepsy is not identified but there are few studies proposing different reasons, all involving the sleep cycle. To understand how narcolepsy affects the brain you first need to understand the sleep cycle.
The sleep cycle consists of two main phases: Rapid Eye Movement (REM) stage and the Non-Rapid Eye Movement (NREM) phase. While you’re asleep, these two phases are repeated constantly at intervals.
Rapid Eye Movement (REM): This is a short phase that lasts for about 10 minutes. During this phase, your heart beat and breathing increases and your eyes move rapidly.
Non-Rapid Eye Movement (NREM): This is a longer phase that may even last for about 90 minutes. It consists of 4 different stages. .
Stage 1 is the where you have just entered the sleep cycle. In this phase you are prone to wake up easily.
Stage 2 is called the light sleep phase. In this phase, your heart rate starts slowing down and your body temperature also decreases. This is the phase where the body prepares you to enter the deep sleep phase.
Stages 3 and 4 are the phases of deep sleep where you may become disoriented for a while if awaken.
In narcolepsy, the sleep cycle starts with REM sleep and occurs involuntarily even during the waking hours. A person having narcolepsy may experience cataplexy (sudden loss of muscle tone or muscle weakness occurring mainly in the the knees, face and neck).
Since you tend to spend most of your time dreaming in REM, strong emotions like anger, fear or happiness are provoked. These strong emotions trigger muscle weakness. The episodes of muscle weakness last for a short while, about a few seconds or minutes.
The common symptoms of narcolepsy are -
- Excessive daytime sleepiness (EDS)
- Poor concentration
‘Patients are also prone to sleep paralysis, where hands and legs start moving during sleep and the patient may get paralyzed,’ says Dr Sudhir.
‘You should consult a doctor if you think you’re not getting adequate sleep or if you think that despite sleeping well the entire night you are feeling sleepy the next day morning,’ he adds. Initial diagnosis is based on your explanation of the problem. The doctor will suspect narcolepsy if your symptoms majorly involve unexplained excessive day time sleepiness.
Sleep latency test: This test analyses how long does it take for you to fall asleep. Your doctor will ask you to take short naps throughout the day. ‘A person with narcolepsy usually falls asleep within 1-2 minutes during this test,’ says Dr Sudhir.
Polysomnography: Further, your doctor may recommend a sleep study called polysomnography. ‘It basically assesses your sleeping pattern and your movement while you’re asleep,’ says Dr Sudhir. During the sleep study, electrodes will be wrapped on different parts of your body with the help of bands and different tests to monitor brain waves (electro-encephalography EEG), muscle tone (electromyography EMG), heart rate (electrocardiography (ECG) and breathing.
Nacrolepsy cannot be cured but the extent of day time sleepiness can be controlled with lifestyle changes and medication.
Medication: ‘Currently, the drug modafinil is the first-line of treatment for patients to reduce daytime sleepiness,’ says Dr Sudhir. Other drugs like antidepressants and gamma-hydroxybutyrate may be prescribed to patients to reduce cataplexy.
Lifestyle changes: ‘Lifestyle changes like reducing weight, exercising regularly and maintaining following a fitness regime can go a long way in helping narcolepsy patients to reduce symptoms,’ says Dr Sudhir. Here are some other lifestyle changes recommended for patients:
- Eat a balanced diet
- Avoid stress
- Try to stick to a sleep schedule
- Try to take naps at well spaced intervals
‘Undiagnosed and untreated narcolepsy increases the risk of accidents and injuries at work and while travelling and driving,’ says Dr Sudhir. Long-term narcolepsy can have serious impact on mental health, relationship and emotional health of the individual.