P0642Discordance between BMI and visceral adiposity identifies distinct inflammatory phenotypes in inflammatory bowel diseases

Abstract Background Inflammatory bowel disease (IBD) is a chronic immune-mediated disorder with distinct metabolic consequences, including altered adipose distribution. Body mass index (BMI) estimates body composition but poorly reflects adipose distribution. Visceral adipose tissue (VAT) may more accurately capture metabolic and inflammatory risk. Intestinal ultrasound (IUS) allows for bedside assessment of both bowel inflammation and VAT. We aimed to define VAT-BMI phenotypes and assess their relationship with intestinal disease activity and metabolic comorbidities. Methods Adult IBD patients undergoing IUS were stratified by BMI (25 vs ≥ 25 kg/m²) and sex-specific median VAT thickness, yielding four VAT-BMI phenotypes: lean (low BMI, low VAT), visceral-predominant (low BMI, high VAT), peripheral (high BMI, low VAT), and combined (high BMI, high VAT). Disease activity, metabolic comorbidities, and biomarkers were compared across phenotypes. Composite disease activity was defined as active inflammation on ≥ 1 of the following within 3 months: IUS (BWT 3mm and/or hyperemia), endoscopic activity, CRP 8mg/L, fecal calprotectin 250mcg/g, or symptomatic activity. Continuous variables were analyzed using one-way ANOVA with Tukey’s post-hoc test for multiple comparisons when overall significance was achieved, and categorical variables were analyzed using the Freeman-Halton (extended Fisher’s exact) test. Statistical significance was defined as p 0.05. Results Among 124 participants (75 Crohn’s disease, 49 ulcerative colitis; 59% male), the median VAT thickness was 33.7mm in males and 28.6mm in females. Phenotype distribution was: lean 34%, peripheral 17%, visceral-predominant 13%, and combined 36%. Composite disease activity differed across phenotypes at 1 month (p = 0.0336): lean 71%, peripheral 52%, visceral-predominant 38%, and combined 44%. Findings were consistent at 3 months (p = 0.0028): lean 81%, peripheral 67%, visceral-predominant 38%, and combined 49%. IUS activity also varied significantly (p = 0.0004), with highest activity in lean and lowest in combined/visceral-predominant phenotypes. Total cholesterol was higher in combined cases (p = 0.049). Diabetes and hypertension were more frequent in the combined and peripheral phenotypes, though not statistically significant (both p = 0.088), likely due to small sample size. Conclusion VAT-BMI discordance identifies distinct inflammatory and metabolic phenotypes in IBD. Lower visceral adiposity was associated with greater intestinal activity, suggesting a potential protective role of visceral fat. Incorporating VAT assessment may enhance disease phenotyping and risk stratification. Conflict of interest: Simkin, Georgia: Consultant for Pfizer, Abbvie, Eli Lilly and Pendopharm, and speaker for Takeda. Maracle, Brooke: No conflict of interest Hazra, Deepan: No conflict of interest Novak, Kerri L.: Research Grants: Helmsley Trust, Pfizer, Janssen Adboard, consulting fees: Abbvie, Janssen, Pfizer, Pendopharm, Takeda, Elli Lilly, Celltrion, Bristal Myers Non financial support (ultrasound machine) McKesson Pharmcy. Pfizer, Celltrion Lu, Cathy: Advisory board - Abbvie, JnJ, Takeda, Ferring, Merck, Celltrion, Pfizer Research Funding - Abbvie, JnJ Kaplan, Gilaad: Grant: Dr. Kaplan received grants for research from Ferring and for educational activities from AbbVie, Bristol Myers Squibb, Ferring, Fresenius-Kabi, Janssen, Pfizer, Takeda. Personal Fees: Dr. Kaplan has received honoraria for speaking or consultancy from AbbVie, Amgen, Janssen, Pfizer, and Takeda. Raman, Maitreyi: Abbvie Johnson & Johnson Celltrion LyfeMD Besney, Jonathan: No conflict of interest Reji, Rohita: None Aldarwish, Alia: No conflict of interest Seow, Cynthia: Advisory boards for Janssen, Abbvie, Takeda, Lilly, Ferring, Shire, Pfizer, Sandoz, Pharmascience, Fresenius Kabi, Amgen, Bristol Myers Squibb, and Celltrion and speaker for Janssen, Abbvie, Takeda, Lilly Ferring, Shire, Pfizer, Pharmascience, and Fresenius Kabi. Ingram, Richard James Michael: Consultancy fees: AbbVie, Amgen, CellTrion, Eli Lilly, J & J Innovative Medicine, Pfizer, Sanofi, Takeda Pharmaceuticals. Speakers’ honoraria: AbbVie, Amgen, BioJAMP, Eli Lilly, Pfizer, Takeda Pharmaceuticals. Stocks: AbbVie, Eli Lilly, Merck (discretionary managed). Ma, Christopher: Consulting fees: AbbVie, Alimentiv, Amgen, Anaptys Bio, AVIR Pharma Inc, Bristol Myers Squibb, Celltrion, Domain Therapeutics, Eupraxia, Eli Lilly, Ferring, Forte Biosciences, Fresenius Kabi, Gilead, Janssen, McKesson, Merck, Mirador Therapeutics, Pendopharm, Pfizer, Roche, Sanofi, Takeda, Tillotts Pharma Speaker’s fees: AbbVie, Amgen, AVIR Pharma Inc, Alimentiv, Bristol Myers Squibb, Eli Lilly, Ferring, Fresenius Kabi, Janssen, Merck, Organon, Pendopharm, Pfizer, Sanofi, Takeda, Tillotts Pharma Royalties: Springer Publishing Research Support: AbbVie, Eli Lilly, Ferring, Pfizer Panaccione, Remo: Grant: Abbvie, Janssen, Pfizer, Takeda Other: Consultant for: Abbott, AbbVie, Abbivax, Alimentiv (formerly Robarts), Amgen, AnaptysBio, Arena Pharmaceuticals, AstraZeneca, Biogen, Boehringer Ingelheim, Bristol-Myers Squibb, Celgene, Celltrion, Cosmos Pharmaceuticals, Eisai, Elan, Eli Lilly, Ferring, Galapagos, Fresenius Kabi, Genentech, Gilead Sciences, Glaxo-Smith Kline, JAMP Bio, Janssen, Merck, Mylan, Novartis, Oppilan Pharma, Organon, Pandion Pharma, Pendopharm, Pfizer, Progenity, Prometheus Biosciences, Protagonist Therapeutics, Roche, Sandoz, Satisfai Health, Shire, Sublimity Therapeutics, Spyre Therapeutics, Takeda Pharmaceuticals, Theravance Biopharma, Trellus, Union Biopharma, Viatris, Ventyx, UCB Speaker’s Fees for: AbbVie, Amgen, Arena Pharmaceuticals, Bristol-Myers Squibb, Celgene, Eli Lilly, Ferring, Fresenius Kabi, Gilead Sciences, Janssen, Merck, Organon, Pfizer, Roche, Sandoz, Shire, Takeda Pharmaceuticals Advisory Boards for: AbbVie, Alimentiv (formerly Robarts), Amgen, Arena Pharmaceuticals, AstraZeneca, Biogen, Boehringer Ingelheim, Bristol-Myers Squibb, Celgene, Eli Lilly, Ferring, Fresenius Kabi, Genentech, Gilead Sciences, Glaxo-Smith Kline, JAMP Bio, Janssen, Merck, Mylan, Novartis, Oppilan Pharma, Organon, Pandion Pharma, Pfizer, Progenity, Protagonist Therapeutics, Roche, SandozShire, Sublimity Therapeutics, Takeda Pharmaceuticals, Ventyx. Dr. St-Pierre, Joelle: Consultant for Pfizer, Abbvie, Eli Lilly and Pendopharm, and speaker for Takeda.