The impact of high body-mass index on cancer mortality in the United States: An emerging public health challenge.

10626 Background: Obesity prevalence has increased markedly in the United States, yet the contribution of high body-mass index (BMI) to age-standardized mortality rates (ASMR) across cancer types, sex, and age groups over three decades remains poorly defined. We evaluated temporal trends in BMI-associated ASMR to identify cancers and populations most affected and inform prevention and equity-focused strategies. Methods: Using Global Burden of Disease (GBD) 2023 data, we extracted U.S. mortality estimates attributable to high BMI for neoplasms overall and selected cancer types from 1990-2023. BMI-associated ASMRs were compared by cancer type and sex, alongside age-specific rates for adults aged 20–54 years and all-age estimates. Age-standardized rates were used to distinguish changes in risk from demographic aging, while age-specific analyses assessed early-onset burden. Results: Between 1990-2023, BMI-attributable cancer mortality among adults aged 20–54 years increased by 44% (1.79 to 2.58), indicating a shift in the population-level burden toward earlier life. Overall BMI-attributable ASMR increased from 7.28 to 7.87, while all-age mortality increased from 9.15 to 14.15. Among evaluated cancers, liver, pancreatic, and uterine cancers demonstrated the largest increases in BMI-attributable ASMR. Liver cancer ASMR increased from 0.29 to 1.02 (~250%), pancreatic cancer from 0.13 to 0.40 (~200%), and uterine cancer from 1.02 to 1.74 (~70%). Early-onset BMI-attributable mortality also increased for liver (0.11 to 0.33), pancreatic (0.04 to 0.12), and colon cancer (0.53 to 0.90). Male predominance was observed for liver, pancreatic, kidney, and colon cancers, whereas uterine cancer accounted for the highest BMI-attributable burden among women. Marked geographic heterogeneity was observed, with the highest-to-lowest state BMI-attributable ASMR ratio of approximately 2.36 in 1990 (District of Columbia vs Hawaii) and 1.75 in 2023 (West Virginia vs Hawaii), indicating persistent but shifting geographic disparities. These patterns suggest amplification of existing cancer inequities at the population level over time. Conclusions: High BMI represents an increasingly important population-level contributor to cancer mortality burden in the U.S., with rising BMI-attributable ASMRs for metabolically associated malignancies and emerging early-onset burden. These findings underscore the importance of obesity prevention and metabolic risk reduction earlier in life as potential strategies to mitigate future cancer mortality and reduce inequities. BMI-associated cancer mortality rates by age group and sex, United States, 1990–2023. Age group / Metric Sex 1990 2023 20-54 Both 1.79 2.58 Female 1.67 2.62 Male 1.91 2.54 All ages Both 9.15 14.15 Female 11.41 16.44 Male 6.77 11.82 Age-standardized Both 7.28 7.87 Female 8.00 8.43 Male 6.29 7.20