title: NREM sleep instability is reduced in children with attention-deficit/hyperactivity disorder.
abstract: OBJECTIVE
  To evaluate non-rapid eye movement sleep instability (NREM), as measured by the cyclic alternating pattern (CAP), in a cohort of children with attention-deficit/hyperactivity disorder (ADHD) and normal controls.
  
  
  METHODS
  Prospective study.
  
  
  METHODS
  Sleep laboratory.
  
  
  METHODS
  Twenty consecutive outpatients with ADHD (18 boys and 2 girls; age range 6-13 years, mean age 9.3 years) and 20 normal children matched for age and socioeconomic status underwent polysomnographic recordings for 2 consecutive nights in a standard laboratory setting. Sleep was visually scored for sleep macrostructure and CAP, according to standard criteria.
  
  
  RESULTS
  Children with ADHD showed significantly reduced sleep duration and increased rate of stage shifts. All children with ADHD had an apnea-hypopnea index less than 1. Those with ADHD presented lower total CAP rates and lower CAP rates during sleep stage 2 than did normal controls. Moreover, in children with ADHD, we found a lower number of CAP sequences and a reduced total A1 index, mainly in light sleep (sleep stages 1 and 2). We did not find differences in A subtype percentages, but there was a longer duration of A1 subtypes in children with ADHD.
  
  
  CONCLUSIONS
  Children with ADHD showed a lower CAP rate and a lower number of CAP sequences; this supports the hypothesis of the existence of a hypoarousal state in these patients.
authors.affiliation: Department of Pediatric, Sleep Disease Centre, University of Rome La Sapienza-S Andrea Hospital, Rome, Italy. silvia.miano@tiscali.it
authors.forename: Silvia
authors.initials: S
authors.lastname: Miano
authors.forename: Renato
authors.initials: R
authors.lastname: Donfrancesco
authors.forename: Oliviero
authors.initials: O
authors.lastname: Bruni
authors.forename: Raffaele
authors.initials: R
authors.lastname: Ferri
authors.forename: Serafina
authors.initials: S
authors.lastname: Galiffa
authors.forename: Jacopo
authors.initials: J
authors.lastname: Pagani
authors.forename: Enza
authors.initials: E
authors.lastname: Montemitro
authors.forename: Leila
authors.initials: L
authors.lastname: Kheirandish
authors.forename: David
authors.initials: D
authors.lastname: Gozal
authors.forename: Maria
authors.initials: M
authors.lastname: Pia Villa
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000503:physiopathology*; D015992:Body Mass Index; D002648:Child; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008297:Male; D010507:Periodicity; D017286:Polysomnography; D011446:Prospective Studies; D012894:Sleep Stages / Q000502:physiology*; D012959:Socioeconomic Factors