Global, regional, and national burden of exposure to chewing tobacco, 1990-2023: a systematic analysis of the Global Burden of Disease Study 2023.

BACKGROUND: Exposure to chewing tobacco is a known health risk factor but has received less attention than smoking in global tobacco control efforts. As the evidence base linking chewing tobacco use to poor health grows, it is essential to closely track the changing use of chewing tobacco distinct from other forms of smokeless tobacco, as well as the estimated burden associated with its use. These data are essential to inform policy makers who seek to identify and avert the health burden associated with these dangerous products.

METHODS: We estimated the prevalence of chewing tobacco use and attributable health burden for individuals aged 15 years and older across 204 countries and territories by age and sex to produce temporal estimates from 1990 to 2023 as part of the Global Burden of Diseases, Injuries, and Risk Factors Study 2023. We leveraged self-reported survey data on use of any smokeless tobacco products spanning 188 countries globally to inform estimates of chewing tobacco use. Further, we undertook a systematic review and meta-analysis using the burden of proof methodology to generate associated relative risks. Together, these estimates served as inputs to generate cause-specific, location-specific, age-specific, sex-specific, and year-specific population-attributable fractions and the resulting attributable measures of health burden.

FINDINGS: In 2023, we estimate 241 million (95% uncertainty interval [UI] 165-355) users of chewing tobacco globally, a prevalence of 3·9% (95% UI 2·7-5·8) among individuals aged 15 years and older. Consumption was concentrated in south Asia, where India had 64·3% (56·1-71·8) of all male chewing tobacco users and 54·8% (47·1-62·4) of all female users. Bangladesh followed with 7·6% (6·0-9·6) and 19·0% (14·5-24·6) of all male and female chewing tobacco users, respectively. Globally, use peaked in older ages, with a prevalence of 5·1% (3·2-8·0) among people aged 60-64 years. Chewing tobacco use was linked to 251 thousand deaths (149-389) in 2023, 152 thousand (96·2-235) of which occurred in males and 99·7 thousand (53·2-164) in females. When adding years of life lost to disability, the total burden attributed to chewing tobacco use was 6·48 million (3·96-9·91) disability-adjusted life-years (DALYs) in 2023. This burden corresponds to 133·5 (85·8-201·8) DALYs per 100 000 males and 66·9 (35·6-109·9) DALYs per 100 000 females. The burden attributable to chewing tobacco was linked to six outcomes, the largest of which was stroke (55·9 [29·0-92·9] DALYs per 100 000 individuals attributable to chewing tobacco) followed by lip and oral cavity cancer (17·4 [11·3-24·3] DALYs per 100 000). However, the underlying epidemiological evidence ranges from moderate to weak.

INTERPRETATION: We observed little change over time in the prevalence of chewing tobacco use, accompanied by a growing burden of associated death and disability. This burden of stroke and head and neck cancers is seen most heavily in south Asia. Chewing tobacco remains an understudied risk factor of public health concern and requires signatories of the WHO Framework Convention on Tobacco Control to increase efforts to reduce exposure alongside those made to mitigate the harms of other tobacco products.

FUNDING: Bloomberg Philanthropies and Gates Foundation.