Abstract
Smoking globally kills over half of long-term smokers and causes about 7 million annual deaths. The World Health Organization Framework Convention for Tobacco Control (FCTC) is the main global policy strategy to combat smoking, but its effectiveness is uncertain. Our interrupted time series analyses compared before- and after-FCTC trends in the numbers and prevalence of smokers below the age of 25 years (when smoking initiation occurs and during which response to interventions is greatest) and on cessation at 45-59 years (when quitting probably occurs) in 170 countries, excluding China. Contrasting the 10 years after FCTC ratification with the income-specific before-FCTC trends, we observed cumulative decreases of 15.5% (95% confidence interval = -33.2 to -0.7) for the numbers of current smokers and decreases of -7.5% (95% CI = -10.6 to -4.5) for the prevalence of smoking below age 25 years. The quit ratio (comparing the numbers of former and ever smokers) at 45-59 years increased by 1.8% (1.2 to 2.3) 10 years after FCTC ratification. Countries raising taxes by at least 10 percentage points concurrent with ratification observed steeper decreases in all three outcomes than countries that did not. Over a decade across 170 countries, the FCTC was associated with 24 million fewer young smokers and 2 million more quitters.