Endocrine Abstracts

Background: Bardet-Biedl syndrome (BBS) is a rare melanocortin-4 receptor (MC4R) pathway disease characterized by early-onset, severe obesity and hyperphagia associated with primary cilia dysfunction. Patients with rare MC4R pathway diseases of obesity and hyperphagia, including BBS, experience high disease burden, but the relationship between hyperphagia and body weight in patients with BBS is not fully understood. We assessed the correlation between hyperphagia score and obesity in children with BBS.

Methods: Data (2014-2021) from CRIBBS, an international registry of patients with BBS, were analyzed. For children who had ≥4 weight assessments, the degree of hyperphagia was derived from the Hyperphagia Questionnaire completed by the caregiver 4 years after CRIBBS recruitment. Hyperphagia Questionnaire scores range from 11 to 55, with higher values indicating more severe hyperphagia. Body weight was measured yearly. Average Hyperphagia Questionnaire scores by weight category (ie, obese, body mass index [BMI] >95th percentile; overweight, BMI ≥85th and <95th percentiles) and the correlation between Hyperphagia Questionnaire score and BMI percentile are reported.

Results: Of 107 eligible children, 39 had the Hyperphagia Questionnaire completed by their caregiver at Year 4 and were included in the analyses. At the time of the hyperphagia assessment, the mean age was 10.4 (range, 4 to 17) years, and 56.4% were male. The mean Hyperphagia Questionnaire score was 24.1 (median, 26.0; range, 11.0 to 39.0). The mean Hyperphagia Questionnaire score increased by weight category, from 13.0 [median, 12.0] among the 5 children (12.8%) with weight within the reference range/underweight to 22.8 [median, 24.0] among the 5 children (12.8%) with overweight and to 26.2 [median, 26.0] among the 29 children (74.4%) with obesity. The Hyperphagia Questionnaire score and BMI percentile were positively and significantly correlated (r=0.34; P=0.03).

Conclusions: Children with BBS experienced burden due to hyperphagia, which was correlated with obesity, suggesting that treatments impacting hyperphagia may result in weight loss and quality of life improvements in these children.