P0395Waist-to-height ratio: a novel predictor of disease course and metabolic comorbidities in inflammatory bowel disease

Abstract Background The impact of obesity on inflammatory bowel disease (IBD) prognosis remains controversial when based on body mass index (BMI). BMI does not reflect visceral adiposity, a major metabolic driver of inflammation. Waist-to-height ratio (WHtR) is a simple surrogate marker of visceral fat and cardiometabolic risk. We aimed to evaluate the association between WHtR and IBD course, and to compare the diagnostic performance of WHtR and BMI for detecting metabolic dysfunction–associated steatotic liver disease (MASLD), metabolic syndrome (MS), and significant liver fibrosis. Methods Ambispective multicentre cohort including IBD patients in clinical remission (University Hospitals of Zaragoza and Santander, 2018–2023). Anthropometric, biochemical, and hepatic assessments were recorded. MASLD was defined by controlled attenuation parameter ≥248 dB/m and ≥1 metabolic risk factor; significant fibrosis by liver stiffness measurement (LSM) 8 kPa. WHtR ≥0.5 indicated visceral adiposity. Disease relapse, steroid use, hospitalization, and treatment modifications were recorded during follow-up. Cox regression models assessed associations between anthropometric measures and clinical outcomes, adjusted for sex, smoking, metabolic comorbidities, Mediterranean diet adherence, disease duration, steroid dependence, and liver fibrosis. Results Among 1,357 patients (641 Crohn’s disease CD, 716 ulcerative colitis UC; median age 48 years, 52% overweight/obese, 74.6% with elevated WHtR), MASLD and MS were present in 39.4% and 19.9%, respectively. Elevated WHtR—but not BMI—was independently associated with IBD prognosis. In CD, high WHtR predicted higher risk of relapse (adjusted HR aHR 1.58; 95%CI 1.10–2.38), steroid use (aHR 1.96; 95%CI 1.12–3.45), and treatment modifications (aHR 1.53; 95%CI 1.10–2.29). Conversely, in UC, high WHtR was linked to lower relapse risk (aHR 0.67; 95%CI 0.49–0.90). WHtR outperformed BMI in identifying MS (sensitivity 99.2% vs 84.1%; p 0.001), MASLD (98.1% vs 83.7%; p 0.001), and significant fibrosis (84.2% vs 68.5%; p 0.001). Nearly half of normal-BMI patients had elevated WHtR (48.8%), revealing substantial metabolic risk in ostensibly lean individuals. Conclusion WHtR is a robust and easily applicable anthropometric marker outperforming BMI in predicting both IBD prognosis and metabolic complications. Elevated WHtR identifies CD patients at higher risk of relapse and therapeutic escalation, while serving as a powerful screening tool for MASLD, MS, and liver fibrosis. Integrating WHtR into routine IBD assessment may improve risk stratification and early intervention strategies. References: 1. Hass DJ, Brensinger CM, Lewis JD, Lichtenstein GR. The impact of increased body mass index on the clinical course of Crohn’s disease. Clin Gastroenterol Hepatol. 2006;4(4):482–8. 2. Dahiya DS, Kichloo A, Wani F, Singh J, Solanki D, Shaka H. A nationwide analysis on the influence of obesity in inflammatory bowel disease hospitalizations. Intest Res. 2022;20(3):342–9. 3. Busetto L, Dicker D, Frühbeck G, Halford JCG, Sbraccia P, Yumuk V, et al. A new framework for the diagnosis, staging and management of obesity in adults. Nat Med. 2024;30:2395–9. 4. Hu Q, Ren J, Li G, Wu X, Li J. Obesity in Inflammatory Bowel Disease: A Marker of Less Severe Disease. Dig Dis Sci. 2015;60(8):2436–45. 5. Nguyen NH, Ohno-Machado L, Sandborn WJ, Singh S. Obesity Is Independently Associated With Higher Annual Burden and Costs of Hospitalization in Patients With Inflammatory Bowel Diseases. Clinical Gastroenterology and Hepatology. 2019 Mar 1;17(4):709-718.e7. Conflict of interest: Mrs. Rivas, Coral: No conflict of interest García Mateo, Sandra: No conflict of interest Martínez-Domínguez, Samuel Jesús: No conflict of interest Alonso Fernández, Sara: No conflict of interest Echavarría, Victor José: No conflict of interest García-Mateo, Sergio: No conflict of interest Rivero Tirado, Montserrat: No conflict of interest Escuín, María: No conflict of interest García, María José: Other: MJ García has received financial support for travelling and educational activities from Janssen, Pfizer, Abbvie, Takeda and Ferring. Gallego, Beatriz: No conflict of interest Castro Senosiain, Beatriz: No conflict of interest Rodríguez-Duque, Juan Carlos: No conflict of interest Alfambra, Erika: No conflict of interest Gargallo-Puyuelo, Carla: No conflict of interest Pascual-Mato, Marta: No conflict of interest Sanchez Ojeda, Inmaculada: No conflict of interest Cobas Bravo, Álvaro: No conflict of interest Arias-Loste, María Teresa: No conflict of interest Gomollón Garcia, Fernando: Grant: MSD, Abbvie, Janssen Personal Fees: Janssen, Abbvie, Takeda Non-financial Support: Janssen, Takeda, Falk,Pfizer