Wednesday, September 20, 2017
Is Excessive Sleepiness Normal?
My 18 year old daughter sleeps all the time. She is very tiny. 5ft tall weight 90 lbs. No eating disorder -- she eats anything she wants. She doesn`t use drugs or alcohol and is happy when she is up and awake. She`s not depressed. She is deaf in one ear and has non verbal learning disorder. Most days she sleeps all but about 5 hours, and sleeps most of the night. She gets up to eat something in the middle of the night and goes back to sleep. I am worried. Is there any medical reasons she would sleep so much?
Excessive daytime sleeping is known as hypersomnia. While teenagers are known to require a lot of sleep (often 10-12 hours in a 24 hour period) and they may keep irregular hours, your daughter clearly has excessive sleepiness for her age.
There are large number of causes for hypersomnia in your daughter’s age group, including infections (mononucleosis, etc), metabolic (anemia, etc), endocrine (thyroid disorders, etc), central nervous system disorders (tumors, previous brain injury), psychiatric disorders (depression), and primary sleep disorders.
Of the sleep disorders that cause sleepiness, one to consider is called narcolepsy. This is a condition where a person may sleep through the night though often has very fragmented sleep. They generally feel refreshed when they wake up but become sleepy again a few hours later. Naps may help the person feel refreshed. There are other symptoms that may go with this condition such as sleep paralysis (person wakes up with a sensation that they can't move), hypnagogic hallucinations (seeing images from dreams as one is falling asleep) and cataplexy (muscle weakness or loss of muscle tone with extreme emotions - particularly laughter). Narcolepsy is diagnosed with a sleep study where you sleep overnight (PSG) and then stay for a series of naps the next day (multiple sleep latency test or MSLT).
Another sleep condition associated with long periods of sleep is called idiopathic hypersomnia. This is a condition where one sleeps all night but does not feel refreshed on awakening and dozes off during the day. Naps are typically not refreshing. This too needs to be diagnosed with a PSG and MSLT.
While the fact that she is happy when up and awake is reassuring, it is a little unusual that she gets up to eat something in the middle of the night.
I think she should be carefully evaluated for different systemic diseases with a good general medical evaluation by her family doctor or pediatrician initially. Then appropriate consultations with other specialists may be needed, depending on the findings or if no cause is found.
Mark Splaingard, MD
Clinical Professor of Pediatrics
College of Medicine
The Ohio State University