Title: Exploration of Tobacco Use Behaviors Amid Societal or Policy Changes and Emerging Tobacco Products in the United States 

Concentration: Epidemiology 

PhD Chair: Dr. Jidong Huang; Co-Chair: Dr. Scott Weaver 

Abstract: 

Over the past two decades, even with the significant tobacco control efforts undertaken in the United States, tobacco use remains the leading preventable cause of death. This three-paper dissertation contributes to the broader understanding of the complex tobacco use behaviors and the factors associated with them in consideration of the COVID-19 pandemic, cannabis legalization policies as well as the increasing popularity of e-cigarettes in the United States. The first paper reports results from quantitative survey data from a national probability online sample of 1460 US adults, and qualitative data from an online focus group study of 61 adults from Atlanta, GA, US. The study found significant differences in tobacco purchasing behaviors between exclusive and dual users of cigarettes and e-cigarettes as well as identified risk perceptions, rising prices of tobacco products and access to tobacco product as factors driving the changes in tobacco purchasing behaviors during COVID-19 pandemic. With the rapidly changing cannabis policies in the US, the second paper reports the findings from a systematic review to understand the impact of such policies on the tobacco use behaviors of adolescents and young adults. The findings suggest a lower likelihood of tobacco use in states with cannabis legalization as compared to states with no cannabis legalization. The review also highlights the limitations in the existing literature that may affect the accurate interpretation of the findings. Overall, this paper informs state, local, or federal policymakers regarding the relationship between state cannabis legalization and tobacco use among adolescents and young adults in the US and guides future research to develop robust findings. The third paper examines the transitions between cigarette and e-cigarette use behaviors over three months, among adult smokers following their past-month initiation or re-initiation of e-cigarettes. The study found a higher likelihood of continuing the same behavior, followed by the likelihood of transitioning towards exclusive cigarette use from predominant cigarette use and towards exclusive e-cigarette use from predominant e-cigarette use among dual users.  The findings from this paper informs policymakers and researchers to develop targeted and timely tobacco control policies and highlights importance of interventions for smoking cessation during early experimentation period of e-cigarette use.