EP464 - ECE_2010 - Hyperphagia severity in adult patients with Bardet-Biedl Syndrome-a mixed-methods cross-sectional study in the United Kingdom

Abstract

Background Bardet-Biedl Syndrome (BBS) is a rare genetic disease frequently associated with hyperphagia, an insatiable feeling of hunger, persistent food-seeking behaviours and abnormal food intake. This can have behavioural, emotional, social and health consequences, and may lead to early-onset obesity. Quantifying the severity of hyperphagia in adult patients with BBS remains challenging due to the limited availability of assessment tools. Objective To assess the level of severity of hyperphagia in adult patients with BBS and obesity living in the UK using an exploratory mixed-method approach. Methods This sub-analysis of a non-interventional, cross-sectional study included 39 adult patients with BBS and obesity. Patients were excluded if they were currently prescribed or had previously taken setmelanotide or if they had a BMI <30 kg/m2. Patients were 41% male, 56% were aged 18-34 years and 82% were of white ethnicity. Patients had a mean (SD) age at diagnosis of BBS of 8.7 (8.1) years. Patients completed a 14-item hyperphagia questionnaire combining multiple-choice and open-ended questions; a subset (n = 13) participated in follow-up semi-structured interviews. Interview transcripts were systematically coded by a qualitative researcher and jointly reviewed with a BBS clinical expert to assign severity ratings. Interviews were designed to contextualise and overcome known limitations of self-reporting in this population, including the disability paradox, stigma, and cognitive difficulties. Results Based on the interviews, 69% (9/13) of patients were classified as having severe hyperphagia, 31% (4/13) as moderate, and none as mild. Questionnaire data classified 8% of patients as having severe hyperphagia, 51% as moderate, and 41% as mild. Notably, 92% (12/13) of patients were assigned a higher severity level via interviews than by questionnaire responses, while only 1 patient had the same severity classification across both methods. Conclusions This study reveals a high prevalence of severe hyperphagia in adult patients with BBS and obesity, and suggest substantial underreporting with self-reported questionnaires. The findings highlight the limitations of questionnaire-based assessments in estimating hyperphagia severity and support the incorporation of expert-led interviews as a more accurate mixed-method approach to better capture the true burden of hyperphagia in adult patients with BB