Let’s face it, restless legs syndrome (also known as RLS or Willis-Ekbom disease) is not exactly a household word in most American families. And the notion that children and teens may have symptoms of this condition is even less appreciated. But let’s take a closer look at what is actually a pretty common sleep disorder and an oft overlooked reason kids have difficulty falling asleep.
RLS is a chronic neurological disorder characterized by a nearly irresistible urge to move, mostly the legs, often accompanied by uncomfortable or unpleasant feelings. These feelings are often described as “creepy-crawly”, “ants crawling on my legs”, “pins and needles.”
The urge (and sensations if present) occur only at rest or are worst at rest/ in the evening. Symptoms are temporarily relieved by movements such as jiggling or jerking the legs, walking around, or rubbing the legs.
It’s not hard to imagine that these symptoms would interfere with falling asleep. And to make matters worse, individuals with restless legs also frequently have what are called “periodic limb movements,” or PLMs, during sleep. These are characterized by sudden flexing of the legs (sometimes described as “kicking”) of which the sleeper is unaware, but which nevertheless can significantly disrupt sleep, leaving the sufferer feeling tired and irritable in the morning. Unlike RLS, which can be diagnosed by patient history, PLMs can only be reliably diagnosed with a sleep study.
So why should parents be informed about the symptoms of RLS?
For one thing, RLS is pretty common in adults and children; best estimates suggest that 10% of adults and about 2% of children age 8-17 years in the United States have symptoms at least once a month (that’s almost 980,000 children!).
RLS is under-diagnosed in general, but especially under-diagnosed in children. This is partly because children may have difficulty verbalizing their symptoms (and partly because no one thought to ask why they have trouble falling asleep!). RLS is also a highly inherited disorder; close relatives of RLS patients have an estimated 6-7 fold increased risk of also having RLS.
Children with RLS suffer daytime consequences as well as sleep disturbance. In particular, RLS symptoms are much more common in children with ADHD (and vice versa). But most importantly, RLS is very treatable.
One of the major contributing factors to RLS is low iron levels, which interfere with the production of a brain chemical called dopamine, known to be reduced in patients with RLS). Another is a blood ferritin level less than 50. This has been shown to increase RLS symptoms, which explains why RLS is so common in pregnant women. However, raising the ferritin level with iron supplements, typically for three months, can greatly relieve discomfort.
Other medications are rarely needed in children. I suggest getting plenty of sleep; avoiding substances that can worsen symptoms such as caffeine, nicotine, alcohol and certain drugs like antihistamines; and trying out massage/applying a hot or cold washcloth to the legs.
If your child or teen has trouble falling asleep, seems uncomfortable or very restless at bedtime, complains of leg pain or discomfort in the evening (otherwise known as “growing pains,” which in some cases are associated with RLS and PLMs) during the night, or seems overly fidgety when sitting still or lying down, talk to your doctor and get your child on the path to a good night’s sleep!
About the blogger: Judith Owens, MD, MPH, is the director of the Center for Pediatric Sleep Disorders and an associate in Neurology. She is deeply committed to providing evidence-based information about the importance of sleep to health, safety and performance to a wide variety of audiences.
Learn more about the Sleep Center at Boston Children’s