Swollen tonsils and adenoids are a major cause of sleep apnoea in children, and while removing them did not improve attention, memory or learning for these kids, it did help them with sleep, behaviour and quality of life, a new study finds.
Sleep apnoea is a condition that causes abnormal pauses in breathing during sleep.
"There was a greater improvement in sleep with the surgery, and those improvements were likely responsible for the improvement in daytime functioning, energy levels and behaviour," said lead researcher Dr Susan Redline, a professor of sleep medicine at Harvard Medical School.
Earlier studies have found that sleep apnoea is associated with mental problems, including attention-deficit/hyperactivity disorder (ADHD), Redline noted. Swollen tonsils and adenoids block a person's airways and restrict breathing, which is why they are the major cause of sleep apnoea in children, Redline explained.
Sleep apnoea may have a harmful effect on memory
Sleep apnoea causes a drop in oxygen levels, which some experts have thought may have a harmful effect on memory and learning, she said. "We thought that by opening the airway we might be able to see greater improvement in these areas," Redline explained.
Removing the tonsils and adenoids, in a procedure called an adenotonsillectomy, however, did not change memory and learning, she noted.
"There have been parents who are worried about their children snoring and sleep apnoea, and have felt nervous that if they didn't rapidly do the surgery they might be exposing their child to poor school performance," Redline said.
This study, however, suggests that if a parent wanted to choose a more conservative approach of watchful waiting, there is no mental decline, she stated.
"Children who are having behaviour problems, are feeling sleepy, are waking up un-refreshed in the morning and dragging during the day are much more likely to get a benefit from early surgery," Redline said.
The report was published online in the New England Journal of Medicine, to coincide with its planned presentation at the American Thoracic Society annual meeting in Philadelphia.
"This is another validation of adenotonsillectomy for the treatment of sleep apnoea in children," said Dr Sandeep Dave, an otolaryngologist at Miami Children's Hospital. "We advise and recommend surgery for sleep apnoea."
Sleep apnoea and mental function
As for whether mental function is harmed by sleep apnoea, "I think the verdict is still out whether or not there are changes in attention-deficit [ADHD]," Dave said.
For the study, 464 children aged 5 to 7 years were randomly assigned to have their tonsils and adenoids removed or to "watchful waiting with supportive care."
Almost half of the children in the study were obese or overweight, the researchers noted. Sleep apnea is more prevalent among obese or overweight kids.
To see whether the surgery improved learning and memory, the children were examined using a test called the Developmental Neuropsychological Assessment.
The researchers found no significant difference in these test results between the children who had surgery and those who didn't.
Children who had surgery, however, showed significant improvements in behavior, sleepiness, executive functioning and quality of life, compared with children in the watchful waiting group, the study authors noted.
Parents were asked to rate how well their child kept up with tasks, got along with other children and planned ahead, and whether they had angry outbursts or mood changes, worried frequently or had trouble sleeping.
These results were confirmed by the children's teachers as well, the researchers added.
Adenotonsillectomy is the primary treatment for sleep apnoea in children. Over half a million US children have the surgery each year, according to the researchers.
For more information on sleep apnea in children, visit the American Sleep Apnea Association.