A study by a University at Buffalo pediatric
researcher investigating the causes of weight gain in
children after they have their tonsils and adenoids removed
to treat sleep-disordered breathing has shown that removing
these tissues results in less fidgeting and other non-exercise
This reduction in motor activity left an excess of calories,
findings showed, resulting in an average 13 percent increase
in excess weight based on participants' age, sex and height.
Results of the study appear in the February 2006 issue
of the journal Pediatrics.
"To our knowledge, the current study is the first to
demonstrate a significant reduction in sleep, waking and
total daily motor activity in children with obstructed
sleep-disordered breathing after removing the tonsils
and adenoids, and the association of reductions in total
daily motor activity with increases in the percent overweight
in children, said James N. Roemmich, M.D., first author
on the study.
Roemmich is an assistant professor in the Department
of Pediatrics, UB School of Medicine and Biomedical Sciences
and in the Department of Exercise and Nutrition Sciences,
UB School of Public Health and Health Professions.
All children in the study underwent the surgery because
they had enlarged adenoids, which can cause obstructive
sleep-disordered breathing (OSDB).
In these young participants, weight gain as a result
of removing the adenoids and tonsils to relieve breathing
problems could create a vicious cycle.
"Weight gain in these children is a concern," said Roemmich.
"Obesity may be a primary cause of OSDB, so additional
weight gain may lead to a reoccurrence of obstructed breathing
during sleep in spite of the surgery."
The study involved 54 children between the ages of 6
and 12 who were admitted to the University of Virginia's
General Clinical Research Center, with which Roemmich
was affiliated at the time.
The participants were assessed before surgery and at
an average of 12.6 months post-surgery. Height, weight,
body-mass index and percent overweight were determined.
During an overnight stay at the clinic, a number of
measurements were taken to determine each child's behavior
during sleep. Parents completed questionnaires on their
child's snoring frequency and the amount of hyperactivity.
A subset of children wore a small motion monitor to log
total amount of activity on their wrists for seven days
Roemmich said there may be several reasons for the children's
reduction in energy expenditure and their subsequent weight
"OSDB causes children to awake many times throughout
the night, resulting in poor sleep quality," said Roemmich.
"There is evidence that inadequate or poor sleep is related
to hyperactivity in youth. Perhaps sleepy kids are more
agitated and have a difficult time attending to tasks.
Improved sleep may reduce hyperactivity, which in turn
would result in less energy expenditure during the day.
"In addition, sleep energy expenditure in children with
obstructed breathing has been reported to decrease by
5 calories per kilogram of body weight after tonsils and
adenoids are removed as a result of the decreased work
of breathing," said Roemmich. "So the reduction in fidgeting
over the entire 24-hours could shift energy balance enough
to cause excessive weight gain."
Further studies on activity and weight changes after
removal of the tonsils and adenoids may provide a basis
for developing diets and exercise plans for these children,
Additional contributors to the study were Jacob E. Barkley,
UB doctoral student in exercise and nutrition sciences;
Lynn D'Andrea, M.D., Margarita Nikova, M.D., Alan D. Rogol,
M.D., and Paul M. Suratt, M.D., from the University of
Virginia School of Medicine, and Mary A. Carskadon, Ph.D.,
from Brown Medical School, Brown University.