Scenarios on years of life lost and life expectancy from 2022 to 2050: a systematic analysis for the Global Burden of Disease Study 2021

Smoking is the leading behavioral risk factor for mortality globally, accounting for more than 175 million deaths and nearly 4·30 billion years of life lost (YLLs) from 1990 to 2021. The pace of decline in smoking prevalence has slowed in recent years for many countries, and although strategies have recently been proposed to achieve tobacco-free generations, none have been implemented to date. Global age-standardized smoking prevalence was estimated to be 28·5% among males and 5·96% among females in 2022. In the reference scenario, smoking prevalence declined by 25·9% among males, and 30·0% among females from 2022 to 2050. Under this scenario, we forecast a cumulative 29·3 billion overall YLLs among males and 22·2 billion YLLs among females over this period. Life expectancy at birth under this scenario would increase from 73·6 years in 2022 to 78·3 years in 2050. Under our Elimination-2023 scenario, we forecast 2·04 billion fewer cumulative YLLs by 2050 compared with the reference scenario, and life expectancy at birth would increase to 77·6 years among males and 81·0 years among females. Under our Elimination-2050 scenario, we forecast 735 million and 141 million cumulative YLLs would be avoided among males and females, respectively. Life expectancy in 2050 would increase to 77·1 years among males and 80·8 years among females. Existing tobacco policies must be maintained if smoking prevalence is to continue to decline as forecast by the reference scenario. In addition, substantial smoking-attributable burden can be avoided by accelerating the pace of smoking elimination. Implementation of new tobacco control policies are crucial in avoiding additional smoking-attributable burden in the coming decades and to ensure that the gains won over the past three decades are not lost.