Hypersomnia in the Paediatric Population

Inclusion Criteria: * For all participants : * Be aged between 6 and 17 (\< 18 years old). * Be able to express consent to participate. * Have at least one legal guardian. * Speak and understand French. * Obtain consent from the person(s) with parental authority (or from one parent if the patient is accompanied by only one parent, in accordance with Article 1122-2 of the Public Health Code) or from the child's legal guardian. * Be affiliated with a Social Security scheme or be covered by such a scheme For patients with CHD : \- Patients with a clinical diagnosis of NT1 according to international criteria (32) with symptom onset (sleepiness and/or cataplexy) dating back no more than two years. The ICSD-3-TR criteria are: SDE lasting at least 3 months, and the presence of one or two of the following: 1. Well-defined cataplexy, with either: * Mean sleep latency of 8 minutes or less on TILEs, and at least 2 episodes of REM sleep onset polysomnography (SOREMP), Or * One episode of SOREMP within 15 minutes of falling asleep during the night of recording. 2. A hypocretin level in the CSF of less than or equal to 110 pg/mL. OR * Patients with a clinical diagnosis of NT2 according to international criteria (30) with onset of sleepiness dating back no more than two years. The ICSD-3 criteria are: SDE evolving for at least 3 years, absence of cataplexy and average sleep latency less than or equal to 8 minutes on TILEs, and at least 2 SOREMPs (one SOREMP the previous night can replace one SOREMP on the TILE). The hypocretin level in the CSF must be greater than 110 pg/mL. In addition, the symptoms and TILE results must not be better explained by other causes (e.g., sleep deprivation, CRD, OSA). * OR * Patients with a clinical diagnosis of IH according to the ICSD-3-TR international criteria, which are as follows: EDS occurring daily for at least 3 months, absence of cataplexy, PSG and MSLT results must not be compatible with narcolepsy (NT1 or NT2): there must be fewer than 2 SOREMPs in total on MSLTs or no SOREMPs if the REM sleep latency on PSG was ≤15 minutes. Also, the presence of at least one of the following two criteria: <!-- --> 1. Mean sleep latency (TILE) ≤ 8 minutes, 2. Total sleep time over 24 hours ≥ 12 hours (or over 32 hours ≥ 19 hours) or measured by continuous 24-hour PSG after ensuring that the patient is not sleep deprived (by actigraphy + sleep diary over at least 7 days of unrestricted sleep). 3. the symptoms of RLS and TILE results must not be better explained by another sleep disorder, medical disorder, psychiatric disorder, or the use of sedative substances or medications. For patients with CRD : -Patients diagnosed with circadian rhythm sleep disorder (CRD) according to ICSD-3-TR, followed up in secondary/tertiary care, with symptoms present for ≥3 months. ICSD-3-TR criteria: Sleeping and waking times consistently delayed by ≥2 hours relative to social schedules (e.g., late bedtime with late wake-up time). \- Symptoms have been present for at least three months. \- When patients are allowed to choose their schedule ad libitum, they show an improvement in sleep quality and duration for their age and maintain a delayed phase of the 24-hour sleep-wake pattern. * Confirmation by sleep diaries or actigraphy over ≥7 days. * Absence of comorbidities that primarily alter the circadian rhythm (e.g., narcolepsy, unstable psychiatric disorders, substance use). For patients with OSA : \- Patients diagnosed with OSA according to ICSD-3-TR, based on polysomnography at a university hospital or specialized center, with at least: * Apnea + hypopnea index ≥ 1 event/hour in patients under 18 years of age, * Plus an associated symptom (snoring, breathing difficulties, daytime sleepiness, or behavioral disorders), * Diagnosis confirmed by a second examination if the first is inconclusive or in the event of comorbidity (obesity, craniofacial malformations). For patients with Non REM parasomnia : \- Children/adolescents diagnosed according to ICSD-3-TR with NREM parasomnias (sleepwalking or night terrors): \- Recurrent episodes (≥2 in 6 months) typically occurring during N3 sleep, with no memory or dream content, \- Confusion/reduced responsiveness during the episode, \- Possible confirmation by video PSG or parental history combined with a sleep diary. For patients with ASD : \- Patients diagnosed with ASD according to DSM-5, confirmed by a multidisciplinary assessment (ADI-R, ADOS-2, ENT-AM) and monitored by a specialized team. Patients must present with phase delay, prolonged insomnia, or severe sleep fragmentation (WASO \> 60 min, latency \> 30 min) as confirmed by actimetry. For patients with ADHD : \- Children/adolescents diagnosed with ADHD according to DSM-5, made by an experienced clinician and confirmed by standardized scales (Conners, ADHD-RS). Must present with sleep disturbances (difficulty falling asleep, WASO \> 30 min, phase delays, etc.), assessed by actimetry or sleep diary, with symptoms established for ≥ 6 months. For patients with obesity : -Children/adolescents with obesity, defined as a body mass index (BMI) above the 97th percentile for age and gender, according to reference curves. The diagnosis is made by an experienced clinician based on standardized anthropometric measurements (weight, height, BMI calculation). They may present with associated sleep disorders (fragmentation, snoring, EDS), as determined by actimetry, polysomnography, or standardized questionnaires. Exclusion Criteria: -Retrait du consentement. * Souhait du mineur d'interrompre l'étude. * Maladie ou condition intercurrente qui interfère avec la poursuite de la participation du sujet à l'étude. * Lors de la visite 2 : si traitement médicamenteux qui agit sur la somnolence ou la vigilance, ou qui n'a pas été stoppé suffisamment tôt. * Décision de l'investigateur.