Narcolepsy Symptoms, Diagnosis and Treatment in Children

Excessive Sleepiness, Attention Problems May Suggest Sleep Disorder

Narcolepsy in children can cause daytime sleepiness, cataplexy, and hallucinations
Narcolepsy in children can cause daytime sleepiness, cataplexy, and hallucinations. Sean Gallup / Getty Images

A sleepy or inattentive child is reason for concern. The critical period of development that stretches from early childhood through adolescence sets the stage for a lifetime of success. This relies on a rested and receptive mind. Problems with attention such as occur in attention deficit hyperactivity disorder (ADHD) may be familiar, but there are other sleep problems that might similarly compromise your child’s ability to learn.

How does narcolepsy affect children? How is it diagnosed and what are the treatments available? Learn more about narcolepsy and how it might unexpectedly affect your child.

The Incidence of Narcolepsy in the Young

Although often considered among adults, narcolepsy actually has two peaks of incidence. Narcolepsy first appears in childhood and adolescence, becoming evident on average around the age of 14.7 years (and then later peaking again at age 35). In fact, more than half of people with narcolepsy report the onset of their symptoms before the age of 20 years.

The younger age of onset is linked to a family history of the disease. In addition, the symptoms that characterize the disease tend to be more severe in those who develop the disease earlier.

Even though the disease may develop at a relatively young age, there is often a delay in the diagnosis of narcolepsy. The symptoms may be overlooked or misinterpreted.

This may result in a delay in the appropriate recognition of the condition an average of 10.5 years after symptom onset.

Symptoms of Narcolepsy in Children

One of the earliest symptoms suggestive of narcolepsy in children is excessive daytime sleepiness, reported in 65.5 percent of cases as the first symptom.

This is somewhat unusual among the sleep disorders in children. Unlike adults who may seem sleepy, children may become hyperactive or irritable when their sleep is compromised. In the case of narcolepsy, however, excessive sleepiness (or hypersomnolence) may be problematic.

Aside from excessive sleepiness, there are other characteristic features of narcolepsy. One of them, cataplexy, is quite unique. People with narcolepsy often exhibit a sudden loss of muscle tone in response to emotional stimuli. For example, surprise might result in a buckling of the knees and sudden collapse. Though this symptom may occur in 60 percent of people with narcolepsy, children do not often present with cataplexy.

Some studies suggest that there may be problems with metabolism in children with narcolepsy. Metabolism is controlled by part of the brain called the hypothalamus, with dysfunction here also linked to narcolepsy. This may result in children who are overweight or obese with an increased body mass index (BMI).

Children may gain weight at the onset of their narcolepsy symptoms.

Children with narcolepsy may be improperly diagnosed with other behavioral or psychiatric problems. The excessive sleepiness may lead to problems with concentration, attention, and learning. This may lead to a diagnosis of ADHD. Children with narcolepsy may be perceived as being depressed, sleepy, or "lazy." They may even be thought to have an absence seizure disorder.

The Diagnosis of Narcolepsy in Children

A careful assessment by a pediatrician, especially one who is knowledgeable in sleep disorders, is the first step toward diagnosing narcolepsy. Additional sleep studies may also be used to diagnose the condition.

The standard sleep study is called a polysomnogram. When considering narcolepsy, it is often paired in children over age 8 with another study called multiple sleep latency testing (MSLT). These tests can be useful to rule out other sleep disorders, including sleep apnea or periodic limb movement syndrome. They may identify a change in the sleep architecture, revealing a lowered threshold for falling asleep and initiating rapid eye movement (REM) sleep.

There are a few other tests that can be used to identify children with narcolepsy. An examination of cerebrospinal fluid (CSF) typically reveals very low to undetectable levels of a chemical messenger, or neurotransmitter, called hypocretin-1. Testing for the human leukocyte antigen DQB1-0602 also may be performed (though this antigen is often present in those who do not have the disease, making it less useful).

Treatment Options for Narcolepsy in Children

As with adults who have narcolepsy, the treatment options in children with narcolepsy include stimulants to minimize daytime sleepiness as well as agents meant to disrupt REM sleep.

Prescription stimulants, including amphetamine-based medication such as modafinil (sold under the brand name Provigil), are used to relieve the excessive daytime sleepiness that characterizes narcolepsy in children.

In addition, it can be helpful to suppress REM sleep with medication, such as selective serotonin reuptake inhibitors (SSRIs) and tricyclic antidepressants (TCAs). As narcolepsy ultimately seems to be due to a problem regulating sleep states, which results in REM sleep inappropriately intruding upon wakefulness, these medicines are helpful. These medications are typically reserved for cases when the other features of narcolepsy are present, including: cataplexy, hallucinations, and sleep paralysis.

Finally, sodium oxybate (sold as Xyrem) has been found to be modestly effective in reducing both excessive daytime sleepiness as well as cataplexy in children.

If you are concerned that your child may have excessive daytime sleepiness and other associated problems suggestive of narcolepsy, you can start by speaking with your pediatrician about your concerns. Further testing can be arranged to determine whether narcolepsy may underlie your concerns, which might prevent a delay in diagnosis and help your child during this critical period of development.

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