ESPE2024 Poster Category 1 Growth and Syndromes 1 (10 abstracts)
1CHU Toulouse, Toulouse, France. 2Université Paul Sabatier, INSERM U1043, Toulouse, France. 3Université Paul Sabatier, UMR1297, Toulouse, France
Purpose: Prader-Willi syndrome is a rare genetic neurodevelopmental condition characterized by cognitive disabilities, behavioural problems, hypothalamic dysfunction with obesity and sleep disorders. A few studies have reported autonomic nervous system dysfunction. Our aim was to investigate in details dysautonomia combining sleep studies and standard autonomic testing in children with Prader-Willi syndrome regularly followed.
Methods: In this retrospective study, heart rate variability was analysed during each sleep stage (polysomnography) using time and frequency domains in children with Prader-Willi syndrome (n = 37) compared with age-matched controls (n = 20). Cardiovascular autonomic testing (“Ewing tests”) and sweating assessment (electrochemical skin conductance) were also performed in patients over 6 years (n = 23).
Results: Autonomic testing: Heart rate changes with active standing and with deep breathing were impaired in 47% and 22% of the children respectively. Asymptomatic orthostatic hypotension was found in 26 %. Baroreflex sensitivity in supine position was relatively low (14.1 ± 6.7 ms/mmHg). Electrochemical skin conductance was normal. Sleep study: 46% of the children with Prader-Willi syndrome had obstructive sleep apnea and 24% central sleep apnea compared to none in the control group. Narcoleptic like phenotype was found in 47% of them and Mean R-R and time domain heart rate variability parameters were significantly lower compared to controls in N2 and REM.
Conclusion: Our study confirms a decreased vagal tone during both wakefulness and sleep in children with Prader-Willi syndrome suggesting a sympathetic dysfunction. These changes may contribute to the increased cardiovascular risk in Prader-Willi syndrome.