Closing the youth access gap: the projected health benefits and cost savings of a national policy to raise the legal smoking age to 21 in the United States.

Current youth access laws, even if strictly enforced, do not prevent teenagers from obtaining cigarettes through social sources. To reduce the number of legal buyers a typical teenager routinely encounters, and to lessen ambiguity for vendors determining if a teen is of legal purchasing age, legislation raising the minimum legal purchase age (MLPA) for cigarettes to 21 has been discussed in several states. To estimate how a national law raising the smoking age to 21 would impact smoking prevalence, net costs (in terms of compliance enforcement, ID checking, and medical care) and health benefits (in terms of life years and QALYs) to the population over time, a dynamic computer simulation model was developed using publicly available secondary data. The model simulations were carried out for several scenarios assuming varying impacts of the policy change on smoking initiation probability over a 50-year period. One scenario assumes that smoking initiation probabilities for individuals under 21 shift by 3 years so a 18-year old in the simulation, for example, is as likely to initiate smoking as an 15-year old in the status quo. Under this assumption, raising the smoking age would reduce smoking prevalence for adults (age 18+) from the status quo level of 22.1-15.4% after 50 years. Prevalence would drop from 20 to 6.6% for 14-17-year olds, from 26.9 to 12.2% for 18-20-year olds, and from 21.8 to 15.5% for the 21+ group. The policy would produce a net cumulative savings to society of 212 billion US dollars (driven by reduced medical costs), and the accumulation of nearly 13 million additional QALYs over the period.