Sleep Disordered Breathing ….and beyond. A must-read!

The following is an article written by Dr. David McIntosh, a paediatric ENT  surgeon in Queensland, Australia. His passions for getting awareness of this subject into the hands of the general public and to medical/dental practitioners is HUGE and is matched only by his knowledge and research on the subject of peadiatric and adult airway issues.
Shared with his permission and encouragement!
Over to you Dr. McIntosh….
How long does it take for a child with sleep-disordered breathing start to have measurable changes reflective of the brain being affected? At what age do these changes first start to be evident?
These are two pertinent questions as there is a cohort of healthcare providers, including ENT surgeons, that advocate a wait and see approach. The philosophy behind this approach is that the main cause of sleep disordered breathing is large tonsils and/or adenoids, and that these both get smaller over time.
Now the first premise is correct- the tonsils and adenoids are the leading cause of upper airway obstruction in children. But they are not the only ones. There are others.
The second premise is based on research from the 1920-30’s by Scammon et al. (Scammon, R. E., The measurement of the body in childhood. In Harris, J, A., Jackson., C, M., Paterson, D, G. and Scammon, R, E. (Eds)．(1930). The Measurement of Man, Univ. of Minnesota Press, Minneapolis).
Now in this research they looked at growth curves of many body organs, including lymphoid tissue. This research was quoted over time and at some time point included the tonsils and adenoids within that description of lymphoid tissue. The problem is that Scammon et al did not look at tonsils or adenoids.
Further research has shown that the tonsils and adenoids do in fact follow the curve of lymphoid tissue provided there is no history of tonsillitis, adenoiditis, or hypertrophic changes of the tonsils or adenoids. (Orofacial Myology: International Perspectives
By Marvin L. Hanson, Robert M. Mason. Page 91.) In other words it is a normal curve for normal tissue. Children presenting with upper airway obstruction due to tonsil or adenoid problems do not have normal tissue. So it is inappropriate to apply the knowledge of Scammon curves to this population of patients.
So back to the original questions- how long does it take to cause a problem, and when does this start to be an issue?
The clues to answering these questions first became apparent in 2012, when this paper was published: https://www.ncbi.nlm.nih.gov/pubmed/22392181
In this study the watched over about 11,000 kids in the first 7 years of their life. All it took was 6 months of consistent sleep disordered breathing to make a difference to childhood development outcomes. I will quote just one part of this very comprehensive paper- “with peak symptoms before 18 months that resolve thereafter still predicted 40% to 50% increased odds of behavior problems at 7 years”. Yes that is right, even when the sleep disordered breathing was left alone, untreated, the children were functioning differently to other children. They did not outgrow the consequences of untreated airway obstruction.
Now when it comes to research, we like it to be repeated and validated. This is where the Canadian Healthy Infant Longitudinal Development (CHILD) research comes in to help. I will quote from the conclusion of this paper- https://www.ncbi.nlm.nih.gov/pubmed/29906629
“…both short sleep duration and SDB were associated with adverse neurodevelopment at two years of age. Children with short nighttime sleep duration had lowered cognitive and language scores and children with persistent SDB also had lower language scores.”
That research also led to this publication- https://www.ncbi.nlm.nih.gov/pubmed/29099980
Note the comment at the end- “Findings suggest that the age of onset and duration of parent-reported SDB symptoms prior to age 2 have adverse consequences for overall behavior problems.” They also did a sleep study along the way and it had no relationship between what is showed and what behavioural outcomes were being identified. This is probably because sleep studies will find sleep apnoea but miss other forms of sleep disordered breathing.
Now it is one thing to show that upper airway obstruction causes problems, it is another thing to show that intervention makes a difference. This is where the Childhood Adenotonsillectomy Trial (CHAT) helps us out. Take, for example, this paper- https://www.ncbi.nlm.nih.gov/pubmed/28199697.
Parents noticed improvements in their child’s behaviour after surgery was performed.
The other paper of note from the CHAT research is this one- https://www.ncbi.nlm.nih.gov/pubmed/23692173
Here they took older children with sleep apnoea (so a worse form of sleep disordered breathing) and either watched for a while or operated. Operating helped, doing nothing did not. There was not a complete resolution which could be related to the fact that they may have had their obstruction for quite a while their obstruction was worse, and/or that adenotonsillectomy was not enough to get the airway sorted as there may have been other issues causing obstruction than just the tonsils and adenoids.
So what does this all mean?
It shows that all children are vulnerable to neurobehavioural complications of sleep disordered breathing and that even young infants and children need help. The notion that “they will outgrow it” is not supported by the contemporary literature and no child should wait longer than 6 months from when parents are worried, to having the airway obstruction relieved. It also shows that no child is too young to be having their airway compromise addressed.