Nutrition and Clinical Outcomes in IBD

The goal of this observational study is to demonstrate that nutritional status and body composition have an impact on clinical outcomes in inflammatory bowel disease (IBD). The main objectives are: 1. To compare the detection rates of undernutrition between a range of nutritional screening tools, physiological measures and assessment tools amongst patients with different IBD phenotypes 2. To correlate nutritional status, nutritional biomarkers and body composition with clinical outcomes in patients with IBD treated with advanced medical therapy or surgery 3. To determine a potential relationship between radiological muscle mass measurements and clinical outcomes in patients with IBD treated with advanced medical therapy or surgery Participants will undergo an assessment at pre-treatment baseline and then again at their scheduled follow-up. This is a non-interventional study and participants will not be required to have any invasive tests or hospital visits beyond that of standard clinical care.