Periodic Limb Movement Disorder and Restless Legs Syndrome in Children With Attention-deficit Hyperactivity Disorder

Abstract

Sleep disruption can lead to symptoms of attention-deficit hyperactivity disorder (ADHD) in children. Since periodic limb movement disorder and/or restless legs syndrome can cause sleep disruption, we assessed whether these two specific sleep disorders are likely to occur in children with ADHD. We asked a series of 69 consecutive parents of children with ADHD questions about the symptoms of periodic limb movement disorder. Based on a positive response to these periodic limb movement disorder queries, 27 children underwent all-night polysomnography. Eighteen children (aged 2 to 15 years) of the 27 (26% of the 69 children with ADHD) had 5 or more periodic leg movements in sleep per hour of sleep and had complaints of sleep disruption, thus fulfilling the criteria for periodic limb movement disorder. A comparably age- and sex-matched group of children referred to a sleep laboratory for sleep complaints but without ADHD showed only a 5% prevalence (2 of 38 subjects) of periodic leg movements in sleep (P=.017). Eight of the 18 children with ADHD and periodic limb movement disorder and one of the two control patients with periodic limb movement disorder had both a personal and parental history of restless legs syndrome symptomatology. This study further documents the occurrence of periodic limb movement disorder and restless legs syndrome in children and is the first large-scale study establishing a possible comorbidity between ADHD and periodic limb movement disorder. We propose that the sleep disruption associated with periodic limb movement disorder and restless legs syndrome and the motor restlessness of restless legs syndrome while awake could contribute to the inattention and hyperactivity seen in a subgroup of ADHD-diagnosed children.

Development of Parasomnias From Childhood to Early Adolescence

“…The presence of leg restlessness at bedtime is highly suggestive of a diagnosis of the RLS, although there was no question in this survey about the worsening of symptoms at rest and the worsening of symptoms in the evening or during the night. However, it should be stressed that in a recent study, Picchietti and coworkers 56 noted that only a small proportion of children with RLS present the International RLS Study Group criteria 17 ; therefore, these criteria should not be considered mandatory for the diagnosis in this population. It may be surprising that in a large portion of children reporting leg restlessness, symptoms disappeared later on during the survey.…”

ADHD and Sleep Problems in Children

“…Picchietti and others looked at the occurrence of PLMD for children with or without ADHD symptoms. In their study, 26% of children with ADHD symptoms had PLMD, compared to 5% of children who did not have ADHD symptoms (Picchietti, 1998). In a study comparing children referred for clinically defined ADHD versus two other groups, those identified as at risk for ADHD from a community survey and children without ADHD, those with clinically determined ADHD had higher PLMs than the other groups suggesting a greater risk for more active and disrupted sleep (O'Brien, 2003).…”

“…Specific criteria for RLS were published in 2003 by NIH (Allen, 2003). While first observed in adults, RLS has been recognized in children for over fifteen years and is estimated to occur in about 2% of children (Walters, 1994;Picchietti, 1998;Pichietti, 2007;Garcia-Borreguero, 2006;Picchietti, 2008).…”

Current Treatment of Selected Pediatric Sleep Disorders

“…For patients with comorbid ADHD, stimulant medications have not been reported to increase RLS/ PLMD symptoms, so long as stimulant effect as worn off by evening [114,115].…”