Restless Legs Syndrome Found a Problem for Children, Too

URBANA, Ill., Aug. 24 -- About 2% of children and adolescents in the U.S. and United Kingdom have restless legs syndrome, estimated an international team on the basis of a large survey.

In the survey of more than 10,000 families in the two nations. 1.9% of those ages eight through 11 and 2% of those ages 12 through 17 had "definite" RLS, Daniel Picchietti, M.D., of the University of Illinois, and colleagues, reported in the August issue of Pediatrics.

Of those, about a quarter to a half reported moderately or severely distressing symptoms that occurred at least twice a week, the researchers found.

Dr. Picchietti said the condition appears to occur more frequently than diabetes and epilepsy, at less than 1% and about 0.05%, respectively.

In adults, the syndrome defined by four characteristics, the researchers noted:

• An urge to move, usually accompanied by unpleasant sensations.
• And symptoms that are worse at rest, relieved by movement, and most severe at night.

There are two pediatric definitions for definite RLS, both more restrictive than the adult definition.

Both require all four adult characteristics and either a description in the child's own words consistent with leg discomfort or two of the following: disturbed sleep, a parent with RLS, or a periodic limb movements of sleep index of five or greater on polysomnography.

Using those definitions, the researcher constructed a survey questionnaire designed to identify RLS children, while discounting such common pains as sore muscles and positional discomfort.

From a large market-research pool in the two nations, they enrolled 11,582 families who had a child in the target range and were initially unaware of the nature of the questions.

Of those, 10,523 completed the survey, including 4,325 with a child ages eight through 11 and 6,198 with a child ages 12 though 17.

Analysis of the results suggested that 81 of the younger group (1.9%) met the criteria for definite RLS, as did 125 of the adolescents (2%), the researchers said.

There were no significant differences on the basis of the sex of the children, the researchers found - a surprise, because in adults the syndrome is usually skewed two-to-one toward females.

Sleep disturbance was reported by 69.4% of the children and adolescents with RLS, compared with 39.6% of those without symptoms, a difference that was significant at P