A large proportion of children with Trisomy 21 are at high risk of obstructive sleep apnea (OSA). These apnea are characterized by an excessive number of respiratory arrests during sleep, leading to under-oxygenized brain and impaired cognitive development. Trisomy 21 per se also impairs both neurocognitive and behavioural developments. The original idea of this prospective study was to analyse whether an early detection of OSA (before the age of 3) and subsequent treatment could improve the neurodevelopment of children with trisomy 21.

Following the clinical observations of Pr Brigitte Fauroux and Dr Aimé Ravel who observed an infant with trisomy 21 getting better after being incidentally diagnosed for OSA and subsequently treated in Pr Fauroux clinical service, the study was launched in 2017. The project recruited 40 children in a 1^st group, with early detection of OSA (starting at 6-months of age) and follow-up until 3 years of age, and in a 2^nd group, 40 children with standard of care protocol of OSA detection at 36-months of age. Children of the 1^st group underwent a first polysomnography (PSG) at 6-month-old followed by additional PSG every 6 months until 36 months of age. Neurocognitive and behavioural outcomes would be evaluated at 36 months of age for all the children, with a follow-up programmed 2 years later.  

Inclusion of children in the study lasted for 2 years and the results of the 3-year follow-up were just published in a Lancet Regional Health Europe journal.

The study was funded in full by the Fondation Jérôme Lejeune.