Temporal trends and disparities in substance use and diabetes mellitus-related mortality in the United States (1999-2022)

BACKGROUND: Substance use (SU) and diabetes mellitus (DM) are major public health concerns and leading causes of mortality in the United States. However, trends examining their combined impact remain limited. This study analyzed mortality trends related to SU and DM from 1999-2022, focusing on demographic disparities, geographic patterns, and substance-specific contributions using Centers for Disease Control and Prevention data. AIM: To examine trends in DM-related mortality involving SU in the United States from 1999-2022, focusing on demographic and geographic disparities and to identify high-risk groups to guide equitable public health interventions. METHODS: Mortality data were obtained from death certificate records. Age-adjusted mortality rates (AAMRs) per 1000000 and annual percentage changes (APCs) with 95% confidence intervals (CIs) were calculated. Temporal trends were assessed using the Joinpoint Regression Program. RESULTS: From the years 1999-2022 127659 adult deaths were disclosed with SU and DM as the primary cause. The overall AAMR rose with an APC of 4.4% (95%CI: 3.6-5.0) from 1999-2016, accelerating to 11.8 (95%CI: 10.2-14.5) from 2016-2022. Gender disparities showed males having higher AAMRs throughout the study period as compared with females. Among racial groups there was a significantly higher AAMR consistently for American Indian/Alaska Natives compared with other races. Geographic analysis showed the highest AAMR in the western states (32/1000000) and pronounced rural increases (APC: 17.6%, 95%CI: 13.2-20.5) after 2018. Alcohol use was the leading contributor (71861 deaths), followed by cocaine and stimulant use. CONCLUSION: This study revealed alarming increases in mortality linked to SU and DM, with widening demographic and geographic disparities. Targeted strategies addressing SU and DM within vulnerable populations are urgently needed to reduce preventable deaths and health inequities.