Restless Legs Syndrome Disturbs Kids' Sleep

Jan. 3, 2005 -- More kids may have restless legs syndrome than previously thought. That could mean sleepless nights and daytime attention problems for children with the condition.

People with restless legs syndrome have a strong urge to move the legs, especially in the evening or at night. They also have a "creepy-crawly" feeling in their legs. The sensation can disrupt sleep, robbing patients of much-needed rest.

"Restless legs syndrome is underdiagnosed in kids," says Suresh Kotagal, MD, chair of Mayo Clinic pediatric neurology, and a sleep specialist, in a news release. "If you look at children with difficulty falling asleep, you'll see a fair number have restless legs."

Symptoms of restless legs syndrome often appear before age 20, but may go undetected in children.

Kotagal chairs the Mayo Clinic's pediatric neurology department. He teamed up with another Mayo Clinic sleep expert, Michael Silber, MD, to study restless legs syndrome in kids. Their study appears in the December issue of the Annals of Neurology.

The pair reviewed records for more than 500 children seen at the Mayo Clinic for sleep disorders. Nearly 6% had restless legs syndrome. The most common symptoms were trouble falling or staying asleep.

That may have affected the children's daytime behavior. Inattentiveness was seen in a quarter of the kids with restless legs syndrome.

"When we look at kids who have decreased attention span, more than one-third of them will have sleep apnea or restless legs syndrome," says Kotagal, in the release. Sleep apnea is a sleep condition in which the person stops breathing for 10 seconds or more during sleep.

Attention problems could have other explanations. Depression, anxiety, stress, and breathing problems are among the reasons why kids may have trouble concentrating.

The study spotlighted two restless legs risk factors: iron deficiency and family history of the syndrome.

Low iron levels were seen in 83% of the kids with restless legs syndrome. Other studies have linked restless legs and low iron levels. However, the connection isn't understood. It's also not clear if getting more iron in the diet or supplements helps tame symptoms.

The syndrome may also run in families. Nearly three-quarters of affected kids had a family history of restless legs syndrome. Mothers were especially vulnerable. They were three times as likely to have had restless legs syndrome than fathers.