TBA (24W121)

Myopenia at induction is associated with non-response in patients with IBD commencing biologics.

Author(s)

McHale, C (1,2) McGettigan, N (1,2) O’Connor, C (2) McDonnell, E (2) Boland, K (1,2)

Department(s)/Institutions

1. Department of Gastroenterology & Hepatology, Beaumont Hospital, Dublin 2. School of Medicine, Royal College of Surgeons in Ireland

Introduction

Current data suggests a link between myopenia and loss of response (as well as non-response) to biologics. It is currently unclear whether this myopenia is a consequence of chronic inflammatory disease or if this is related to high levels of particular circulating cytokines in IBD, especially considering that this differential response has been reported predominantly with anti-TNF agents.

Aims/Background

We sought to examine the relationship between biologic response and muscle mass to identify patients who are less likely to respond to biologics and require closer monitoring.

Method

Patients with moderate-severe IBD were recruited prospectively as part of an ongoing RCT assessing a physician-led exercise programme in patients with IBD. Muscle mass was measured at baseline using previously validated tools, BIA (Seca-mBCA 525) and thigh ultrasound. Muscle function was measured using hand-grip strength. Mucosal response was defined as > 50% reduction in SES_CD score or fall in MAYO score of 1. Statistical analysis was completed using Minitab. Binary logistic regression models were adjusted for age, gender and diagnosis.

Results

Twenty-nine patients have outcome data available at this time. The mean age of this cohort was 44 years and the majority were males (65.5%). 15/29 had a diagnosis of UC and 12/29 had CD. The majority of patients commenced infliximab at time of recruitment (51.7%, n=15) and 44.8% (n=13) of patients were biologic naive. A binary logistic regression model indicated that higher appendicular skeletal muscle mass, indicating high skeletal muscle volume is associated with mucosal response or mucosal healing (p=0.038). While there was a numerical trend towards increase in mean waist circumference after biologic induction in mucosal responders (3 cm) vs non responders (1.8 cm), this was not statistically significant (p=0.08).

Conclusions

Whilst recruitment is still ongoing, this data provides a signal that myopenia or lower muscle mass may predict biologic failure and may be a useful tool in the assessment of patients with IBD at biologic induction to identify those at higher risk of non-response or surgery.