Trends and disparities in diabetes-associated cancer mortality in the United States, 1999–2020.

11190 Background: Diabetes mellitus (DM) is increasingly recognized as an important contributor to cancer mortality, yet long-term population-level trends and sociodemographic disparities in diabetes-associated cancer deaths in the United States remain insufficiently characterized. Methods: We analyzed U.S. Multiple Cause of Death data from the CDC WONDER database for 1999–2020. Deaths with neoplasia as the underlying cause of death and diabetes mellitus listed as a contributing cause were included. Annual deaths and crude mortality rates were examined across year, Census region, state, 2013 urbanization level, 10-year age groups, sex, race, and Hispanic origin. Temporal trends were quantified using average annual percent change (AAPC) derived from log-linear regression models over the 1999–2020 period. Results: From 1999–2020, diabetes-related neoplasia deaths totaled 588,693 (mean 26,759/year), with annual deaths rising 77.9% (20,427 in 1999 to 36,343 in 2020) and crude mortality increasing 50.7% (7.3 to 11.0 per 100,000), corresponding to an overall AAPC +1.24%/year. By sex, trends increased faster in males (AAPC +1.75%) than females (AAPC +0.55%). By Census region, AAPC was highest in the West (+2.00%) and South (+1.98%), followed by the Midwest (+0.65%), while the Northeast declined (−0.30%). By 2013 urbanization, the steepest rises occurred in Noncore nonmetro (+2.43%) and Micropolitan nonmetro (+1.61%), exceeding Medium metro (+1.54%), Small metro (+1.22%), Large central metro (+0.97%), and Large fringe metro (+0.80%). By race, AAPC was highest for American Indian/Alaska Native (+2.38%) and Asian/Pacific Islander (+2.30%), followed by White (+1.45%) and Black (+0.30%). By Hispanic origin, AAPC was higher in Hispanic/Latino (+2.42%) than Not Hispanic/Latino (+1.33%) (Not stated: insufficient rate series for AAPC). By age, increases were greatest at 35–44 years (+1.45%) and 25–34 years (+1.18%), with smaller increases at 45–54 (+0.62%) and ≥85 (+0.62%), while older mid-life groups declined (65–74: −0.61%, 55–64: −0.27%, 75–84: −0.04%). State-level AAPC ranged from Kentucky (+6.55%), Arizona (+5.07%), Oklahoma (+4.81%), Colorado (+4.66%), and Arkansas (+4.61%) to District of Columbia (−3.44%), Connecticut (−2.91%), Massachusetts (−1.88%), Illinois (−1.38%), and Delaware (−1.24%). Conclusions: Diabetes-associated cancer mortality increased substantially in the United States from 1999–2020, with widening disparities by geography, urbanization, race/ethnicity, sex, and age. The disproportionate rise in rural areas, younger adults, and select racial and ethnic groups underscores the need for integrated cancer–diabetes prevention strategies and targeted public health interventions to mitigate future mortality burden.