Early Detection and Treatment of Obstructive Sleep Apnoea in Infants With Down Syndrome

Inclusion criteria : Down Syndrome Age 6 months or less for the Study Group Age 30 to 36 months for the Standard Care Group Living in Paris or Paris area (75, 77, 78, 92, 93, 94, 95) Parents or legal representative agreeing with the study requirements and able to understand, date and sign the informed consent form before study enrollment French language is native mother tongue Exclusion criteria : Gestationnel age \< 36 completed amenorrhoea weeks Patient who have or had acute CNS suffering signs Patients with Down Syndrome already had continuous positive airway pressure treatment for OSA Patients participating in another clinical study or for whom a participation to another biomedical research is expected before the end or their follow-up