NREM sleep instability is reduced in children with attention-deficit/hyperactivity disorder.
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.
Miano
Silvia
S
Department of Pediatric, Sleep Disease Centre, University of Rome La Sapienza-S Andrea Hospital, Rome, Italy. silvia.miano@tiscali.it
Donfrancesco
Renato
R
Bruni
Oliviero
O
Ferri
Raffaele
R
Galiffa
Serafina
S
Pagani
Jacopo
J
Montemitro
Enza
E
Kheirandish
Leila
L
Gozal
David
D
Pia Villa
Maria
M
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