title: Periodic limb movement disorder of sleep in children.
abstract: To characterize periodic limb movement disorder (PLMD) in a cohort of prepubertal children we examined sleep-related identifiable differences between children with PLMD and attention-deficit/hyperactivity disorder (ADHD), PLMD alone, and age-matched controls. Children were selected from a chart review of all children referred to a pediatric sleep medicine center and from a community survey of 5-7-year-old-children. Polysomnography (PSG) and parental report data from all children identified as having periodic limb movement index (PLMI) >5 were reviewed and compared with a cohort of age-matched controls. A total of 8.4% of children in the clinic-referred sample, and 11.9% of the children recruited from the community had PLMI >5. Of those, 44.4% were identified as having ADHD. Children with PLMD had significantly lower percentage of rapid eye movement (REM) than control children (P < 0.001). Children in the PLMD/ADHD group had a significantly greater number of arousals associated with PLM (PLMa) than children with PLMD only (P < 0.05). While a relationship between ADHD and PLMD was observed, it was weaker than previous reports (Chervin, R. D. et al. Sleep, 2002; 25: 213; Chervin, R. D. and Archbold, K. H. Sleep, 2001; 24: 313; Picchietti et al. J. Child Neurol., 1999; 13: 588; Picchietti et al. Mov. Disord., 1999; 14: 1000; Picchietti and Walters Sleep, 1999; 22: 297). Children in the PLMD/ADHD group were more likely to have PLMas than were children with PLMD only. We postulate that rather than a direct relationship between ADHD and PLMD, this link may be mediated by the presence of reduced REM sleep and more importantly by the sleep fragmentation associated with PLM-induced arousals.
authors.affiliation: Kosair Children's Hospital Research Institute, Division of Pediatric Sleep Medicine, Department of Pediatrics, University of Louisville School of Medicine, 571 S. Preston Street, Louisville, KY 40202, USA.
authors.forename: Valerie McLaughlin
authors.initials: VM
authors.lastname: Crabtree
authors.forename: Anna
authors.initials: A
authors.lastname: Ivanenko
authors.forename: Louise Margaret
authors.initials: LM
authors.lastname: O'Brien
authors.forename: David
authors.initials: D
authors.lastname: Gozal
mesh_terms: D001289:Attention Deficit Disorder with Hyperactivity / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D020189:Nocturnal Myoclonus Syndrome / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology; D017286:Polysomnography / Q000379:methods; D012720:Severity of Illness Index; D012892:Sleep Deprivation / Q000175:diagnosis / Q000209:etiology; D012895:Sleep, REM / Q000502:physiology; D011795:Surveys and Questionnaires