Shifts in waist-to-height ratio categories within tirzepatide groups: a post-hoc analysis of SURMOUNT-1.

“Shifts in waist-to-height ratio categories within tirzepatide groups: a post-hoc analysis of SURMOUNT-1. Sattar N(1), Tchang BG(2), Vincent RP(3)(4), Wang H(5), Murphy M(5), Dunn JP(5), Dimitriadis GK(5), Fraseur Brumm J(6). Author information: (1)School of Cardiovascular and Metabolic Health, University of Glasgow, Glasgow, UK. (2)Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, Comprehensive Weight Control Center, Weill Cornell Medicine, New York, USA. (3)King's College Hospital NHS Foundation Trust, London, UK. (4)Faculty of Life Sciences and Medicine, King's College London, London, UK. (5)Eli Lilly and Company, Indianapolis, IN, USA. (6)Eli Lilly and Company, Indianapolis, IN, USA. fraseur_julia@lilly.com. OBJECTIVE: To evaluate shifts in waist-to-height ratio (WHtR) categories among adults with obesity or overweight, with or without prediabetes, treated with tirzepatide in the SURMOUNT-1 study. METHODS: This post hoc analysis included 2,538 participants from the SURMOUNT-1 Phase 3, double-blind, randomized, placebo-controlled trial. Adults with BMI ≥ 30 or ≥ 27 kg/m² and at least one obesity-related complication (ORC), excluding diabetes, were randomized to receive once-weekly tirzepatide (5, 10, or 15 mg) or placebo, alongside a reduced-calorie diet and increased physical activity. Participants were grouped by baseline WHtR (≤ 0.49, > 0.49 to ≤ 0.59, > 0.59) according to the National Institute for Health and Care Excellence (NICE) framework. Participants with prediabetes at baseline had additional follow-up data beyond week 72, and shifts in their WHtR categories at week 176 were also included. Change from baseline in WHtR was analyzed using a mixed model for repeated measures (MMRM). Shift tables were used to summarize changes from baseline to post-baseline WHtR category levels. RESULTS: At baseline, 89.8% of participants had a WHtR > 0.59, 10.1% had > 0.49 to ≤ 0.59, and 0.1% had ≤ 0.49. After 72 weeks of tirzepatide (10/15 mg), 16.7% of participants achieved a WHtR ≤ 0.49, and 54.7% improved their baseline WHtR category compared to 9.6% with placebo. At 176 weeks, among participants with prediabetes, 12.2% achieved WHtR ≤ 0.49, and 46.4% improved their category with tirzepatide versus 9.3% with placebo. CONCLUSIONS: Tirzepatide treatment was associated with sustained improvements in WHtR categories, with a greater proportion of participants shifting to a better WHtR category compared to participants treated with placebo. Improved WHtR may be suggestive of lower future cardiometabolic risk. Further analyses of this nature will enhance the understanding and application of WHtR in obesity management across diverse populations. © 2026. The Author(s). Conflict of interest statement: Declarations. Conflict of interest: Naveed Sattar received grants, consulting fees and honoraria from Astra Zeneca, Boehringer Ingelheim, Novartis and Roche and consulting fees from AbbVie, Amgen, Carmot Therapeutics, Eli Lilly, Gan & Lee, GlaxoSmithKline, Hanmi Pharmaceuticals, Kailera, Mass Medicines, Menarini-Ricerche, Metsera, Novo Nordisk, Pfizer, Regeneron, and Verdiva Bio. He has also received honoraria from AbbVie, Amgen, Eli Lilly, Novo Nordisk, and UCB Pharma. He serves as the Chair of the HM Government Office for Life Sciences’ Obesity Healthcare Programme. Beverly G. Tchang received consulting fees from Kailera and participated on the advisory boards of Wake Forest DSMB, Johns Hopkins University DSMB, Novo Nordisk, Roman Health Ventures, Skye Bioscience, Amgen, Eli Lilly and Company, Boehringer Ingelheim, Pfizer, and Circadian Care. She serves as a board member of Tri-state Obesity Society and The Obesity Society and has received stock options from Roman Health Ventures. Royce P. Vincent has received grants from Recordati, Novo Nordisk and Novartis Pharma AG. Madhumita Murphy, Julia P. Dunn, Georgios K. Dimitriadis and Julia Fraseur Brumm are employees and shareholders of Eli Lilly and Company. Hui Wang was an employee of Eli Lilly and Company during the course of the study. Ethics approval and consent to participate: This study was conducted in accordance with the ethical principles of Good Clinical Practice and the Declaration of Helsinki and its guidelines. An independent ethics committee or institutional review board approved the SURMOUNT-1 protocol. The original SURMOUNT-1 participant consent covered the analyses in this study. Consent for publication: Not applicable.”