RESUMEN
OBJECTIVE: To investigate the association of state-level cigarette price and tobacco control expenditure with the large 2000-2019 decline in cigarette smoking among US 18-24 year-olds. METHODS: Smoking behaviour was assessed in the 24 most populous US states using the 1992-2019 Tobacco Use Supplements to the Current Population Survey; association with price and expenditure was tested using adjusted logistic regression. States were ranked by inflation-adjusted average price and tobacco control expenditure and grouped into tertiles. State-specific time trends were estimated, with slope changes in 2001/2002 and 2010/2011. RESULTS: Between 2000 and 2010, the odds of smoking among US young adults decreased by a third (adjusted OR, AOR 0.68, 95% CI 0.56 to 0.84). By 2019, these odds were one-quarter of their 2000 level (AOR 0.24, 95% CI 0.19 to 0.31). Among states in the lowest tertile of price/expenditure tobacco control activity, initially higher young adult smoking decreased by 13 percentage points from 2010 to 2018-2019, to a prevalence of 5.6% (95% CI 4.5% to 6.8%), equal to that in the highest tobacco-control tertile of states (6.5%, 95% CI 5.2% to 7.8%). Neither state tobacco control spending (AOR 1.0, 95% CI 0.999 to 1.002) nor cigarette price (AOR 0.96, 95% CI: 0.92 to 1.01) were associated with young adult smoking in statistical models. In 2019, seven states had prevalence over 3 SDs higher than the 24-state mean. CONCLUSION: National programmes may have filled a gap in state-level interventions, helping drive down the social acceptability of cigarette smoking among young adults across all states. Additional interventions are needed to assist high-prevalence states to further reduce smoking.