Trajectories of Cigarette Smoking From Teens to Young Adulthood: 2000 to 2013.

PURPOSE

To identify trajectories of smoking behaviors of a cohort of youth followed through young adulthood from 2000 to 2013.

DESIGN

The Minnesota Adolescent Community Cohort study, a population-based cohort study.

SETTING

Nationwide, originating in the Midwestern United States.

PARTICIPANTS

Cohort of youth surveyed for 14 years beginning at ages 12 to 16 (N = 4241 at baseline; 59% recruitment rate).

MEASURES

Main variable of interest was the number of days smoked in the past 30 days. Also included time-varying and time-invariant covariates.

ANALYSIS

We utilized growth mixture modeling to group individuals into trajectories over time.

RESULTS

We identified 5 distinct trajectories: nonsmokers (59.5%), early-onset regular smokers (14.2%), occasional smokers (11.5%), late-onset regular smokers (9.4%), and quitters (5.3%). Adjusted models showed that early- and late-onset regular smokers (compared to nonsmokers) had lower odds of attending or graduating from a 4-year college ( P < .05). Participants in all smoking classes compared to nonsmokers had greater odds of having more close friends who smoked ( P < .05).

CONCLUSION

Our results show that individuals in their teens through young adulthood can be classified into 5 smoking trajectories. More people in this age range remained abstainers than found in most previous studies; however, a sizable group was identified as regular smokers by the time they reached young adulthood. Interventions targeted at teens, including those that address social and environmental influences, are clearly still needed to prevent escalation of smoking as they move toward young adulthood.