SALT LAKE CITY – Restless legs syndrome is common, troublesome, and rarely diagnosed in children and teens, Dr. Daniel Picchietti reported at the annual meeting of the Associated Professional Sleep Societies.
Multiple case reports, practice-based study findings, and adult studies showing that more than a third of patients report symptom onset prior to age 20 have hinted at a relatively high prevalence in children. Findings from the Peds REST Study–a large population-based study–provide confirmation of that, said Dr. Picchietti of the University of Illinois, Urbana.
In that study of children from more than 10,500 families in the United States and United Kingdom, the prevalence of definite restless legs syndrome (RLS) by the National Institutes of Health consensus criteria definition was 1.9% in children aged 8–11 years, and 2.0% in those aged 12–17 years, suggesting RLS occurs more often than epilepsy or diabetes in this population, he said.
Restless legs syndrome is a neurologic disorder characterized by unpleasant sensations in the legs, and an uncontrollable urge to move them for relief. Some affected individuals describe the sensations as burning, tugging, or creeping, or like insects crawling inside the legs, according to the National Institute of Neurological Disorders and Stroke.
To meet the official diagnosis, patients must meet these NIH criteria:
▸ A strong urge to move the legs, which patients may not be able to resist.
▸ RLS symptoms start or become worse when resting.
▸ Symptoms improve when patients move their legs. The relief can be complete or only partial, but generally starts very soon after activity.
▸ Symptoms are worse in the evening, especially when patients are lying down.
In the study, moderately to severely distressing symptoms that occurred more than twice weekly were reported by 0.5% of those aged 8–11 years, and by 1.0% of those aged 12–17 years. Furthermore, sleep disturbance and growing pains were significantly more common in those with RLS than in controls, 50% of those with RLS reported the condition had a negative effect on mood, and several medical diagnoses were reported more commonly in RLS patients than would be expected in the general population.
In the U.S. population, for example, RLS patients were commonly diagnosed with ADHD (27%), anxiety disorder (11%), and depression (12%).
Data were collected randomly via Internet survey in April 2005 from a large volunteer research panel. Participants were initially blinded to the survey topic.
Responses were provided by the parents of those participants in the 8- to 11-year-old range, and by either parents or the adolescents themselves of those in the 12- to 17-year-old range. Only answers from biologically related parents and children were included in the analysis so the role of family history could be ascertained.
Descriptions of RLS symptoms that were provided by children in their own words were convincing in regard to whether they were truly affected by RLS.
“I really got the sense that this was restless legs syndrome–that we got exactly what we were measuring,” Dr. Picchietti said, explaining that there was concern about discerning RLS symptoms from other arthralgias and cramps of childhood.
The good news is that some of those with RLS were diagnosed, but the bad news is that even among those who were moderately to severely affected, fewer than one in six received a diagnosis. Also, treatment was very uncommon, he said.
In the present study RLS occurred equally in males and females in the pediatric population, while among adults, twice as many females as males are affected.
Another finding from Peds REST is that a family history of RLS (in at least one parent) is common in affected individuals. In one in six families with a child with RLS, both parents reported experiencing RLS symptoms, Dr. Picchietti noted.