Children with sleep apnea syndrome who have their tonsils and adenoids removed sleep better, are less restless and impulsive, and report a generally better quality of life, finds a new study funded by the National Institutes of Health. However, the study found cognitive abilities did not improve compared with children who did not have surgery, and researchers say the findings don’t mean surgery is an automatic first choice.

The findings of the Childhood Adenotonsillectomy Trial (CHAT) were presented May 21 at the American Thoracic Society 2013 meeting in Philadelphia. The study, which compared surgery to general supportive care and observation, or watchful waiting, is published online in the New England Journal of Medicine.

“This is the first rigorous, controlled evaluation of a commonly performed treatment for childhood sleep apnea, in terms of looking at functional outcomes,” said Susan Shurin, MD, a pediatrician and deputy director of the NIH’s National Heart, Lung, and Blood Institute (NHLBI). “This study provides additional data that can help parents and providers make more informed decisions about treating children with this disorder, and it identifies additional areas of research.”

CHAT enrolled 464 children ages 5-9 years with obstructive sleep apnea syndrome from seven sleep centers across the United States and randomly assigned them into two groups. One received adenoid and tonsil surgery within a month after enrollment, while the other received supportive medical care and careful monitoring, or watchful waiting. At enrollment, both groups of children were evaluated by psychometricians—people trained to administer and interpret psychological tests—on their cognition (primarily attention and organizational skills); they were also evaluated by caregivers and teachers on behavior and quality of life, and they had sleep studies to assess their breathing and sleep parameters. After seven months, the children were reevaluated.

The researchers found no differences in cognitive skills between the two groups, but the children who underwent surgery showed improved sleep quality, behavioral regulation, and quality of life measures like being more active and experiencing less daytime sleepiness. Beneficial effects were observed even among overweight children, in whom there has been particular uncertainty about the role of surgery for sleep apnea treatment.

Overall, 79% of children in the surgery group had resolution of their sleep apnea after seven months, compared to 46% in the watchful waiting group.