National trends and disparities in mortality involving bladder cancer and substance use disorders in the United States, 1999-2023.

Background: Although bladder cancer mortality has modestly declined in the United States, co-occurring substance use disorders (SUDs) may contribute to adverse outcomes and widening health disparities among affected individuals. This study evaluated temporal trends in mortality involving both bladder cancer and SUDs in the United States between 1999 and 2023. Methods: Mortality data related to patients aged ≥25 were obtained from the CDC WONDER Database. Deaths involving bladder cancer were identified using ICD-10 code C67 in combination with ICD-10 codes F10-F19 for substance use disorders listed among multiple causes of death. Age-adjusted mortality rates (AAMRs) per 100,000 population were calculated and Joinpoint regression was used to estimate annual percent changes (APCs) and average annual percent changes (AAPCs). Results: Between 1999 and 2023, 63,258 deaths involving both bladder cancer and SUDs were identified. Overall, the AAMR increased significantly at an annual average percentage change (AAPC) of 13.38% (95% CI: 10.69-16.14). Males had a substantially higher mortality burden than females (50,299 vs 12,959). White individuals and adults aged ≥85 were accounted for the largest mortality burden. Mortality rates were consistently higher in nonmetropolitan populations and increased across all U.S. census regions. Conclusion: Mortality involving bladder cancer and coexisting SUDs increased over time and mirrored broader national substance-related mortality trends. These findings support integrated oncology- and addiction-focused care approaches, as well as public health strategies aimed at improving access to cancer care, addiction treatment, and rural health services.