Impairment of the production of delta sleep in anorectic adolescents.
OBJECTIVE
Total sleep time and slow-wave sleep (SWS) are frequently reported to be reduced in anorectics. A preliminary study showed that slow-wave activity (SWA, 0.5-4.5 Hz) is decreased in anorectic adolescents. The present study investigates whether this reduction is the result of the increased sleep fragmentation or is dependent on an intrinsic weakness of SWA-producing mechanisms.


METHODS
Statistical analysis of spectral electroencephalogram data recorded during sleep from a group of anorectics and a control group.


METHODS
Polysomnographic data were recorded in single rooms in the hospital for 1 night following an adaptation night.


METHODS
20 adolescent anorectic girls (13.9 +/- 2.0 years) and 12 age-matched control subjects.


METHODS
Refeeding and psychotherapy.


RESULTS
Anorectics had an increase of wakefulness after sleep onset, a higher number of arousals, and a reduction of SWS and SWA during total sleep time. No relationship between the reduction of SWA and duration of illness was found, while a relationship between SWA decrease and the level of emaciation (body mass index) was present. The analysis limited to the first non-rapid eye movement sleep cycle did not show any difference between the 2 groups in the number of awakenings and arousals. Nevertheless, anorectics showed a reduction of SWS and SWA.


CONCLUSIONS
Sleep of anorectic patients seems to be characterized by an impairment of SWA-producing mechanisms independent of the increased sleep fragmentation. This is probably related to the primary pathophysiologic characteristics of the illness but could also reflect secondary functional and anatomic alterations of the brain.
Nobili
Lino
L
Child Neuropsychiatry Department-University of Genoa, Gaslini Institute, Genoa, Italy.
Baglietto
Maria G
MG
Beelke
Manolo
M
De Carli
Fabrizio
F
Di Comite
Raffaella
R
Fiocchi
Isabella
I
Rizzo
Pierpaolo
P
Veneselli
Edvige
E
Savoini
Margherita
M
Zanotto
Elisabetta
E
Ferrillo
Franco
F
D000293:Adolescent; D000856:Anorexia Nervosa / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy; D015992:Body Mass Index; D001921:Brain / Q000033:anatomy & histology / Q000503:physiopathology; D002648:Child; D003700:Delta Rhythm; D004569:Electroencephalography; D005260:Female; D006801:Humans; D017286:Polysomnography; D012720:Severity of Illness Index; D012890:Sleep / Q000502:physiology*; D020178:Sleep Disorders, Circadian Rhythm / Q000175:diagnosis / Q000503:physiopathology*; D012895:Sleep, REM / Q000502:physiology; D014851:Wakefulness / Q000502:physiology