Children with Asperger syndrome have a high prevalence of some sleep disorders

Nov 2 2007

The first known attempt to evaluate the sleep patterns of children with Asperper Syndrome (AS), taking into account sleep architecture and the cyclic alternating pattern (CAP), finds that children with AS have a high prevalence of some sleep disorders and mainly problems related to initiating sleep and sleep restlessness together with morning problems and daytime sleepiness, according to a study published in the November 1 issue of the journal SLEEP.

The study, authored by Oliviero Bruni, MD, of the Center for Pediatric Sleep Disorders at University La Sapienza in Rome, Italy, focused on eight children with AS, 10 children with autism and 12 healthy control children. The parents of the children with AS filled out the following materials:

• Sleep questionnaire.
• Pediatric Daytime Sleepiness Scale, which evaluates the relationship between daytime sleepiness and school-related outcomes.
• Autism Diagnostic Observation Schedule, a semi-structured, standardized assessment of communication, social interaction and play or imaginative use of materials for individuals who have been referred because of possible autism spectrum disorders.
• Child Behavior Checklist, a questionnaire used to examine daytime behavior in children.

In addition, the children took the Wechsler Intelligence Scale for Children, which measures verbal IQ, performance IQ and a full-scale IQ, and also underwent an overnight polysomnogram, or sleep study.

Several sleep parameters, such as time in bed, sleep period time, number of awakenings per hour, and sleep efficiency, were evaluated. CAP, a periodic EEG activity of non-REM sleep characterized by repeated spontaneous sequences of short-lived events (phase A) with the return to background activity identifying the interval that separates the repetitive elements (phase B), was also scored.

According to the results, 50 percent of the children with AS were reluctant to go to bed, while 75 percent felt a need for light or a television in the bedroom, 87 percent had difficulty getting to sleep at night and 75 percent fell asleep sweating. In addition, 50 percent felt unrefreshed when waking up in the morning, 87 percent had difficulty waking up in the morning and 87 percent felt sleepy during the day.

With respect to the CAP, in comparison to healthy controls, subjects with AS showed a lower total CAP rate in the first two sleep stages, but not in slow wave sleep. In addition, they showed an increased percentage of synchronized EEG patterns and a decreased percentage of desynchronized EEG patterns. Further, the duration of the A and B phases, and consequently the entire CAP cycle, was longer. Compared to the children with autism, AS subjects showed an increased CAP rate in slow wave sleep and a decrease in the second sleep stage. The duration of the A phases was longer, as well as the CAP cycle duration.

“This study showed peculiar CAP modifications in children with AS and represented an attempt to correlate the quantification of sleep EEG oscillations with the degree of mental ability or disability,” said Dr. Bruni.

AS is one of several autism spectrum disorders (ASDs) characterized by difficulties in social interaction and by restricted and stereotyped interests and activities. AS is distinguished from the other ASDs in having no general delay in language or cognitive development. Although it is not mentioned in standard diagnostic criteria, there are frequent reports of motor clumsiness and atypical use of language.

It is recommended that children in pre-school sleep between 11-13 hours a night, school-aged children between 10-11 hours of sleep a night, and adolescents about nine hours a night.

The American Academy of Sleep Medicine (AASM) offers some tips to help your child sleep better:

• Follow a consistent bedtime routine. Set aside 10 to 30 minutes to get your child ready to go to sleep each night.
• Establish a relaxing setting at bedtime.
• Interact with your child at bedtime. Don't let the TV, computer or video games take your place.
• Keep your children from TV programs, movies, and video games that are not right for their age.
• Do not let your child fall asleep while being held, rocked, fed a bottle, or while nursing.
• At bedtime, do not allow your child to have foods or drinks that contain caffeine. This includes chocolate and sodas. Try not to give him or her any medicine that has a stimulant at bedtime. This includes cough medicines and decongestants.

Children are encouraged to inform their parents of any sleep problems they may have. Parents who suspect that their child might be suffering from a sleep disorder are encouraged to consult with their child's pediatrician or a sleep specialist.