Spatiotemporal Dynamics in the Burden of Lip and Oral Cavity Cancer and Attributable Risk Factors in Asia (1990-2021).

Lip and oral cavity cancer (LOC) remains a critical public health challenge in Asia. This study evaluated spatiotemporal trends and risk factor contributions to LOC-related disability-adjusted life years (DALYs) from 1990 to 2021 to inform evidence-based healthcare policies. Using Global Burden of Disease (GBD) 2021 data, we analyzed LOC DALYs stratified by age, gender, risk factors (smoking, alcohol use, tobacco chewing), and subregions in Asia. Temporal trends were quantified via estimated annual percentage change (EAPC) across five geographic regions and sociodemographic index (SDI) categories. Age-period-cohort (APC) modeling was used to assess age-specific risk distributions. From 1990 to 2021, Asia's age-standardized DALY rate (ASDR) for LOC marginally increased (EAPC: 0.0883, 95% CI: 0.0802-0.0963). The alcohol-related ASDR increased sharply (EAPC: 1.033, 95% CI: 1.00-1.06), whereas decreases were detected in the smoking- and tobacco chewing-attributable ASDRs. Pronounced upward trends were observed in South Asia and low/low-middle-SDI regions. Tobacco chewing was the primary risk factor for women and for the populations in South Asia and lower-SDI regions, whereas smoking dominated among men and those in other geographic regions and in higher-SDI areas. APC analysis revealed age-driven increases in ASDR, with alcohol use and tobacco chewing risk increased with age. Notably, the steepest ASDR increase occurred in individuals aged 20-25 years. The LOC burden in Asia reflects divergent risk factor dynamics. Policy strategies must prioritize geographic and demographic targeting: alcohol control in rapidly developing areas and intensified tobacco cessation programs in endemic zones. Early prevention efforts focusing on adolescents and tailored to subregional risk profiles are essential to mitigate future disease burden.