Endocrine Abstracts

JOINT1633

Introduction: Hyperphagia, overweight or obesity have been more frequently reported in people with intellectual disability (ID) and in rare neurodevelopmental disorders (NDDs. Amongst these conditions, people with Prader-Willi syndrome (PWS) display a characteristic nutritional trajectory ranging from anorexia to hyperphagia, leading to early severe obesity. From a pathophysiological perspective, PWS is the only identified genetic cause of obesity associated with hyperghrelinemia. The aim of our HOGRID study is to describe ghrelin levels and hyperphagia in patients followed by centers of the national rare NDDs network “Filière DéfiScience”.

Methods: HOGRID is a cross-sectional, non-interventional, national multicenter clinical study. Patients underwent a single study visit during their routine follow-up comprising fasting blood sampling to assess ghrelin levels, clinical examination and completion of a series of questionnaires notably to assess hyperphagia, using the Hyperphagia Questionnaire (HQ). Inclusion criteria were: patients between 3 and 50 years with a rare NDD such as classical syndromic obesity (Bardet-Biedl syndrome, Alström syndrome, Angelman syndrome, Smith-Magenis syndrome, X-Fragile syndrome) and other rare NDD associated with overweight/obesity and/or feeding troubles. In order to compare ghrelin levels we used three ”control groups“ from our previous published study “PWS” group (n = 153), “Obese” group (n = 49) and “Lean” group” (n = 31). In these groups ghrelin levels were assessed in the same laboratory as in the HOGRID study.

Results: We included 130 patients with a median age of 19.8 years (3 to 47 years), 43% were children (n = 56), 54% were boys, 27% were overweight, 59% obese and 14% lean. Total ghrelin levels of the HOGRID population were statistically lower than “PWS” (P < 0.001) and “Lean” (P < 0.001) groups and similar to those of the “Obese” group. In children, the mean total HQ score (P = 0.042) and the mean Hyperphagic Behavior susbscore (P = 0.008) were significantly higher in the HOGRID population than in the “PWS” group. In adults, compared with the “PWS” group, there was a trend for a lower total HQ score (P = 0.053), and a significantly lower Hyperphagic Behavior (P = 0.03) and Severity (P = 0.046) susbscores.

Conclusion: We did not find hyperghrelinemia in the HOGRID population, confirming that hyperghrelinemia is specific to the “PWS” group. Children in the HOGRID population seem to display higher hyperphagia than PWS children, which was not observed in adults. This suggests that possibly due to early diagnosis of PWS in the first month of life and early multidisciplinary care, hyperphagia in PWS may be more easily controlled in children than in adults.