Identifying "social smoking" U.S. young adults using an empirically-driven approach.

The phenomenon of "social smoking" emerged in the past decade as an important area of research, largely due to its high prevalence in young adults. The purpose of this study was to identify classes of young adult ever smokers based on measures of social and contextual influences on tobacco use. Latent class models were developed using social smoking measures, and not the frequency or quantity of tobacco use. Data come from a national sample of young adult ever smokers aged 18-24 (Truth Initiative Young Adult Cohort Study, N=1564). The optimal models identified three latent classes: Class 1 - nonsmokers (52%); Class 2 - social smokers (18%); and Class 3 - smokers (30%). Nearly 60% of the "social smoker" class self-identified as a social smoker, 30% as an ex-smoker/tried smoking, and 12% as a non-smoker. The "social smoker" class was most likely to report using tobacco mainly or only with others. Past 30-day cigarette use was highest in the "smoker" class. Hookah use was highest in the "social smoker" class. Other tobacco and e-cigarette use was similar in the "social smoker" and "smoker" classes. Past 30-day tobacco and e-cigarette use was present for all products in the "non-smoker" class. Young adult social smokers emerge empirically as a sizable, distinct class from other smokers, even without accounting for tobacco use frequency or intensity. The prevalence of hookah use in "social smokers" indicates a group for which the social aspect of tobacco use could drive experimentation and progression to regular use.