Even though disease, Narcolepsy can be identified positively through physical observation, physicians are still misdiagnosing patients. Misdiagnosis happens especially when dealing with those that have psychological problems. Clinical evidence suggest that tests on a patient’s cerebrospinal fluids (CSF) can nearly confirm Narcolepsy, as 90% of Narcoleptics tested in studies have shown to have no hypocretin-1 in their CSF.
Often doctors will rely on symptom reporting by patients, questionnaires, testing sleep latencies in patients, and monitoring a patient as he/she sleeps and may not test the patient’s CSF before starting therapy. Doctors can however be firm in their diagnosis by observing the presence of nearly all Narcolepsy symptoms together in a patient. The confirmation of cataplexy, for example confirms a patient has Narcolepsy, as it is unique to Narcolepsy.
Diagnosis and treatment of Narcolepsy is somewhat standardized but methods and drugs vary from patient to patient most of the time. Upon diagnosis doctors usually choose to prescribe two frontline medications (modafinil, sodium oxybate). Both of these drugs are habit forming and sodium oxybate can be very dangerous. For this reason the process of diagnosis may take some time because the doctor wants to be sure of his diagnosis before prescribing it.
Most patients do not receive their Narcolepsy diagnosis until ten to fifteen years after the first symptoms start appearing. For a doctor to make a correct narcolepsy diagnosis they must take into consideration the patient’s family and medical history. This includes the medications the patient is taking and any even what the person eats regularly. Diagnosing narcolepsy becomes easy when the patient exhibits all major narcolepsy symptoms listed below:
Excessive daytime sleepiness (EDS) and an urge to take frequent naps during the day. These daytime naps must happen every day for six months at least in order for it to be considered as solid basis for narcolepsy diagnosis. Diagnosing narcolepsy is common in young adults and adolescents; bringing the problem to their attention when they suddenly fall asleep at school or at work. Sometimes, patients also experience insomnia but the majority of time a narcoleptic will have no issue falling asleep and entering almost directly into REM sleep.
Cataplexy or sudden muscle weakness and loss of muscle control and tone, causing the patient to stop motor activity.
Visual or auditory hypnagogic hallucinations that occur right before falling asleep.
The inability to move upon awakening, or sleep paralysis.
However, narcolepsy diagnosis that’s based solely on symptoms can be problematic for several reasons. One reason is that some patients that receive a Narcolepsy diagnosis often seek medical advice for just one symptom (frequently hypnagogic hallucinations or sleep paralysis) which could be caused by other similar disorders; epilepsy in particular. Another reason for the difficulty in the diagnosis of narcolepsy is that the symptoms do not always become apparent to anyone for several years. This is true for the patient himself and even to a skilled observer. In certain cases, a patient is required to consult specialists in the field, or get treated and monitored at a sleep disorder clinic for a more effective treatment for Narcolepsy and to confirm that a patient does indeed have Narcolepsy.
Questionnaires for Diagnosing Narcolepsy
The Epworth Sleepiness Scale is one of the questionnaires for sleeping habits that a doctor can administer to get a more reliable narcolepsy diagnosis. The ESS makes use of simple questions in measuring excessive sleepiness; differentiating it from the normal sleepiness we usually feel in the daytime. See figure 02-01a for the test.
Figure 02-01a: The Epworth Sleepiness Scale
*Note this test varies slightly with different results analysis.
|Chance of Dozing0-none1-slight chance2-moderate chance3-high chance|
|Sitting and reading||Indicate score (0-3)|
|Sitting inactively in public places||Indicate score (0-3)|
|As a car passenger for one whole hour without any breaks||Indicate score (0-3)|
|Watching television||Indicate score (0-3)|
|Sitting and talking to someone||Indicate score (0-3)|
|Sitting quietly after lunch (without alcohol)||Indicate score (0-3)|
|In a car stuck for a few minutes in traffic||Indicate score (0-3)|
|Lying down for an afternoon rest when circumstances allow||Indicate score (0-3)|
|Show Results||1 – 6: Getting enough sleep7 – 8: Tends to be sleepy but is average9 – 15: Very sleepy and must seek medical adviceOver 16: Dangerously sleepy|
Multiple Sleep Latency Tests
MSLT or multiple sleep latency tests can also help in making an accurate Narcolepsy diagnosis. The MSLT makes use of a device that can measure the time a patient takes to fall completely asleep during the day while lying inside a quiet room. Patients are asked to take 4-5 scheduled naps that are 2 hours apart. People with healthy sleeping habits usually fall asleep in 10-20 minutes. However, patients with a diagnosis of Narcolepsy show a significantly shorter time duration; approximately less than eight minutes, when moving from wakefulness to sleep. At least two of these naps are REM sleeps; the sleep state associated with dreaming. Still, the test has its limitations. There is no clear definition which abnormal results are proven to be basis for diagnosing narcolepsy. The Epworth Sleepiness Scale might be more precise in identifying narcolepsy from regular daytime sleepiness.
Polysomnography is a study of an overnight sleep that can prove valuable in determining the major cause of sleepiness. A patient, without changing any of his daily habits, goes to the sleep centre two hours before bedtime. Various devices are used to monitor the patient while he sleeps:
- The ECG or electrocardiogram monitors the patient’s heart
- The EEG or electroencephalogram monitors the brain’s electrical activity
- The Electrooculogram monitors the eye movements
- The Electromyogram monitors muscle movements
With these instruments, doctors can record a patient’s condition, and monitor activity as their patients pass, or fail passing, through the stages of sleep. Neuroimaging methods can also be used in studying or confirming physiological sleep theories and discovering new relevant information about neurobiological aspects of the human sleep, memory and dreams. A few studies in neuroimaging focus on subjects suffering from narcolepsy and other sleep disorders.
Narcolepsy Diagnosis and Narcolepsy Treatments are carefully adapting with new findings. Newer drugs are replacing older ones and doctors are diagnosing patients with better confidence. With proper diagnosis Narcolepsy symptoms can be treated quickly and nearly all signs and symptoms of the neurological disorder can be substantially reduced.