Global Burden of Lip and Oral Cavity Cancer Attributed to Different Tobacco Use From 1990 to 2021 and Projection to 2050

INTRODUCTION AND AIMS: Lip and oral cavity cancer (LOCC) remains a significant global health challenge, with tobacco use being its primary modifiable risk factor. However, a comprehensive understanding of the LOCC burden attributable to different forms of tobacco use is lacking. This study aims to systematically quantify the global, regional, and national burden of LOCC attributable to smoking and chewing tobacco from 1990 to 2021 and to project trends to 2050, providing evidence for targeted tobacco control policies. METHODS: Using data from the Global Burden of Disease (GBD) 2021 study, we extracted mortality and disability-adjusted life years (DALYs) for LOCC attributable to tobacco smoking and chewing tobacco. Age-standardized mortality rates (ASMR) and DALY rates (ASDR) were analysed by sex, region, and Socio-demographic Index (SDI). Cross-country inequality was assessed using the Slope Index and Concentration Index. A Bayesian age-period-cohort (BAPC) model was employed to forecast the burden to 2050. RESULTS: Globally, between 1990 and 2021, absolute tobacco-attributable LOCC deaths nearly doubled, while the ASMR declined (from 1.07 to 0.94 per 100,000). This decline was driven entirely by smoking, whereas the burden from chewing tobacco increased slightly. Striking disparities emerged: the burden in females remained stable, driven primarily by chewing tobacco, while males saw a decline driven by reduced smoking. Regionally, South Asia bore the highest burden. Inequality analysis revealed narrowing disparities for smoking-attributable LOCC but persistent, unaddressed inequality for chewing tobacco. BAPC projections to 2050 forecast a continued decline in smoking-attributable burden but no improvement for chewing tobacco-attributable burden. CONCLUSION: While global tobacco control efforts have successfully reduced the smoking-attributable LOCC burden, the persistent and, in some populations, increasing burden from chewing tobacco - particularly among females and in low-SDI regions - demands urgent attention. Projections indicate that without targeted intervention, chewing tobacco will remain an unmitigated cause of LOCC for decades. CLINICAL RELEVANCE: Targeted tobacco control is urgently needed for the reduction of LOCC burden in specified populations.