It might feel like sleeping all the time, but narcoleptics do not sleep more than people with healthy sleep cycles. The nighttime sleep cycle is interrupted from insomnia, sleep apnea or another sleep disorder. The result is the need to make up for it during daytime hours.
Clinical features
The diagnosis of narcolepsy depends on the existence of several symptoms. Narcoleptics suffer from EDS, seventy percent also suffer from cataplexy and a smaller portion has regular episodes of sleep paralysis with or without hallucinations. It is exceedingly rare for any one patient with narcolepsy to suffer from all of these symptoms. Often, one or more are present.
- EDS
The defining symptom of narcolepsy is Excessive Daytime Sleepiness (EDS) it is just what it sounds like. The feeling is of being very sleepy during the day, followed by sleep attacks. It is not exhaustion. It is not just tired. The desire to sleep is so strong it becomes need, uncontrollable need to sleep. The narcoleptic does not fall asleep all the time because he or she is lazy, but because it is unstoppable.
- Cataplexy
The diagnosis of narcolepsy with cataplexy is separate from narcolepsy without cataplexy. Narcolepsy with cataplexy has its own biomarker. There is a noticeable deficiency in the protein hypocretin-1 in the hypothalamus in most patients with narcolepsy with cataplexy. This deficiency brings the possibility of an autoimmune dysfunction as the cause of this symptom. This is good news as it gives scientists another angle from which to search for treatments.
Patients with narcolepsy with cataplexy condition, suffer from falling asleep all the time like patients without cataplexy, but they also have episodes where their muscles lose tone and they lose the ability to control them. The experience can be as slight as the drooping of an eyelid and as extreme as total collapse and can last from a few seconds to over an hour. Unlike narcolepsy, with this symptom, the patient is completely alert and awake.
Narcolepsy symptoms like the loss of muscle control experienced in cataplexy may only leave you with your hands falling asleep all the time.
- Sleep Paralysis
Sleep paralysis is experienced by a large portion of the population once or twice in a lifetime. Narcoleptics that have sleep paralysis have these episodes frequently. The sensation is a lot like cataplexy in that the patient is alert but has no control over their body. It does not however, depend on the deficiency of hypocretin. Instead, sleep paralysis is experienced in the twilight between wake and sleep. This symptom is often accompanied by hallucinations.
- Hallucinations
In normal REM sleep, the body loses tone and dreams. Narcolepsy patients sometimes experience this while waking or falling asleep.
Hallucinations experienced when a patient is falling asleep are called hypnogogic hallucinations. When hallucinations are experienced between the REM cycles and coming fully awake it is called hypnopompic hallucinations.
These hallucinations are often surreal and dark and they can sometimes be mistaken for something supernatural like an out of body experience or possession.
Misdiagnosis
There are several diseases that share overlapping symptoms with narcolepsy. As a result, getting the correct diagnosis and treatment can be a tricky task. Many psychiatric illnesses can look like narcolepsy. Patients with major depressive disorder (MDD), bipolar disorder, and psychotic disorders often display narcolepsy like symptoms. . Mood disorders are often accompanied by insomnia. When a Patient’s in the depressed phase of bipolar disorder or has MMD, they could have EDS on top of the fatigue that is common to the disease.
The easiest psychiatric disorder to mistake for narcolepsy is schizophrenia. The commonalities between the two make it very easy to misdiagnose. Both narcolepsy and schizophrenia usually start during adolescence or early adulthood. Schizophrenia patients can have insomnia and hallucinations are found in both cases. Misdiagnosing these two diseases means that the patient is getting inappropriate treatments. Narcolepsy patients would find the sedative effects of many antipsychotics only worsen their EDS a. Schizophrenics would likewise find that stimulants have adverse effects on their disorder.
On top of the psychiatric diseases that can lead to misdiagnosis, there are several neurology based disorders that can initially look like narcolepsy. The cataplexy and sleep attacks can have the appearance of a seizure. Two more neurological disorders that share commonalities with narcolepsy are Parkinson’s disease and Alzheimer’s disease.
Diagnostic Tools
There are no sure ways to test for narcolepsy. There is no known genetic testing and no blood tests that show the presence of the disease. Diagnosis of narcolepsy is dependent on observation and detailed histories. In the absence of a physical test, the Multiple Sleep Latency Test or MSLT is the accepted standard of testing for testing sleep drive and excessive sleepiness. The doctor will probably order a nocturnal Polysomnogram where the patient will be hooked up to an electroencephalogram (EEG) the night before the MSLT to collect data on breathing, heart rate, waking and sleep activity as well as snoring, apnea, sleep talking or other physical activities while sleeping that may explain the presence of EDS.
The test is preformed the next day in the same clinical setting during the rest of the day. There are 5 scheduled naps that last for 20 minutes, every 2 hours. The room where the patient is to nap is made as comfortable and sleep inducing as possible. Stimulation is avoided, the temperature and noise level is kept at a perfect setting and then the patient is left to try to sleep.
The purpose of the MSLT is to determine the presence or absence of REM sleep during the first 15 minutes of the nap. Taking an average of 8 minutes or less to fall asleep over the total 5 naps and experiencing REM sleep during at least 2 of them, is the current criteria for a diagnosis of narcolepsy.
If you find yourself thinking “I fall asleep all time” then you should talk to your doctor. A local sleep clinic can provide you with literature and advise you which specialists are available.