P0312 Sarcopenia as a feature of musculoskeletal manifestations of paediatric Crohn’s disease
Authors: Daichendt L , Kalia V , Ross I , Ali A , Sawicka J , Miller M , Wells S , Rashmikant Suthar N , Berard R , Crowley E 
Published: January 2025

Abstract

Background
Musculoskeletal (MSK) manifestations are the most common extraintestinal manifestation (EIM) of Crohn’s disease (CD). Features include arthralgias, axial/peripheral arthritis, enthesitis, tenosynovitis and dactylitis. CD is associated with impaired nutritional status which can lead to unintentional loss of skeletal muscle mass, known as sarcopenia. Few studies report on sarcopenia in paediatric CD, but it is estimated to affect up to one-third of patients and may be associated with more treatment refractory disease and poorer quality of life.1 This study aims to investigate the prevalence of sarcopenia in paediatric CD, in paediatric CD with MSK EIM and to assess the impact of sarcopenia on CD related clinical outcomes.

Methods
In this single centre, retrospective cohort study, data were collected from 139 newly diagnosed (&lt; 1 year) paediatric CD patients who had undergone magnetic resonance enterography (MRE) at the Children’s Hospital, London Health Sciences Center (Ontario, Canada) over four years (2019 – 2023). Bowel disease activity was assessed by weighted paediatric Crohn’s disease activity index (wPCDAI) scores. Sarcopenia was assessed, by an MSK-trained radiologist, by measuring total psoas muscle area (tPMA) from MRE images and comparing to age and sex matched reference values.2 Sarcopenia was defined as a tPMA z-score less than – 2.0. Univariate descriptive statistics were used.

Results
139 patients with CD were included (mean age 13.1 ± 3.1 years, 59% male). Sarcopenia was found in 22 patients (15.8%). Children with sarcopenia had lower body surface area (BSA) (p=0.020), higher wPCDAI scores (p=0.033), higher ESR (p=0.035), lower hemoglobin (Hb) (p&lt;0.001) and a higher number of hospital admissions (p=0.041) compared to children without sarcopenia. Of these, 52 children (37.4%) had MSK EIM. Among the 52 patients with CD-MSK EIM, 7 had sarcopenia (13.5%) [Table 1]. No statistically significant difference was found in the prevalence of sarcopenia in patients with CD-MSK EIM compared to CD-alone (17.2%) (p=0.555). Only 15.8% (22/139) of the total cohort and 40% (21/52) of the MSK-EIM group had seen a rheumatologist.

Conclusion
Initial findings demonstrate that 15.8% of paediatric patients with CD have sarcopenia. Of those with CD-MSK EIM, 13.5% have sarcopenia. At baseline, patients with CD related sarcopenia did demonstrate higher bowel disease activity, increased admissions to hospital and more systemic inflammation (higher ESR, lower Hb). Limitations of this study include the lack of systematic rheumatology assessment of CD patients for MSK EIM, resulting in potential under-reporting of MSK-EIM. Further analyses are planned to evaluate the impact of sarcopenia on bowel disease outcomes over time in both groups.

References
1.Atlan L, Cohen S, Shiran S, Sira LB, Pratt LT, Yerushalmy-Feler A. Sarcopenia is a Predictor for Adverse Clinical Outcome in Pediatric Inflammatory Bowel Disease. J Pediatr Gastroenterol Nutr. 2021;72(6):883-888. doi:10.1097/MPG.0000000000003091
2.Lurz E, Patel H, Lebovic G, et al. Paediatric reference values for total psoas muscle area. J Cachexia Sarcopenia Muscle. 2020;11(2):405-414. doi:10.1002/jcsm.12514