Many children have difficulty sleeping. But a disproportionate number of children
with special needs have sleep problems.
Anywhere from 49 to 89% of children with autism spectrum disorders, 25
to 50% of children with ADHD, and 34 to 86% of children with cognitive
impairments are estimated to experience sleep difficulties. Additionally children with other syndromes,
such as Angelman or Down syndromes, are also reported to have sleep
difficulties. But what is not known is
if the learning problems cause the sleep problems, or if the sleep problems
cause the learning problems. Dr. Bonuck
and her associates from the Albert Einstein College of Medicine attempted
to answer this question in a prospective study just published in Pediatrics by looking for an association
between sleep difficulties in young children with a later need for special
education services.
Prospective studies follow a specific population (or cohort)
over time, identify certain risk factors, and see how these factors affect
outcomes over time. The Avon Longitudinal Study of Parents and Children (also
known as ‘the Children of the 90s’ study) is one such cohort that had enrolled approximately
85% of pregnant women in Avon, England in 1991-1992, allowing for a large
population-based study. The initial
cohort in the study, which was used by Dr. Bonuck and her associates for their
research, comprised more than 13,000 infants, but children with any known condition
that might lead to a disability or was associated with a disability were excluded.
Dr. Bonuck examined the effects of sleep disordered
breathing and behavioral sleep problems on children. Parents of the children in the study had reported
on their child’s sleep at 6, 18, 30, 42, and 57 months. Based on parent report, children were divided
into two groups. Those with sleep
disordered breathing (SDB) either snored, had apnea, or mouth breathed. Those children with behavioral sleep problems
(BSPs) refused to go to bed, had trouble settling, awoke during the night, or
had nightmares. For the SDB group, 11,049
children were identified; For the BSP group, 11,467 children were identified. Researchers found that children with sleep
disordered breathing had an approximately 40% increased risk of needing special
education services by age 8. The need
for special education services increased to 60% for those children in the worst
symptom cluster. For those children
with behavioral sleep problems, the risk of needing special education services
increased approximately 7% per year of reported symptoms.
The Avon Longitudinal Study cohort was also used in an
earlier study by Dr. Bonuck, which demonstrated that children with sleep
disordered breathing from 6 to 69 months had a 60% higher risk of behavioral problems, including hyperactivity, anxiety,
and depression, by ages 4 and 7. According to Dr. Bonuck, disordered
breathing, such as occurs in apnea or snoring, may mean that the brain is
getting too little oxygen or too much carbon dioxide, which may in turn affect areas
of the brain used for paying attention or regulating emotion.
These studies do not prove cause and effect; they merely
show an association. But in the eyes of
the researchers, children with these sleep issues may very much be at risk of development
of long-term disabilities due to their sleep difficulties. Thus, Dr. Bonuck argues that sleep disorders
must be considered neither routine nor normal, or in the case of children with
special needs, expected. Pediatricians
need to screen for and treat sleep problems, particularly in the child’s first
year of life, to avoid future difficulties for the child. Whereas many parents regard snoring as a sign
that their child is getting a good night’s sleep, in reality the snoring can be
indicative of obstructive sleep apnea or enlarged tonsils, which can be
treated. Of children with special
needs, only about half of children with sleep disorders are treated. Ultimately
a good night’s sleep will benefit everyone, not only the child, but also his or
her exhausted parents.