E-cigarette use among treatment-seeking smokers: Moderation of abstinence by use frequency.

INTRODUCTION: Emerging literature suggests that frequency of use of electronic cigarettes (e-cigarettes) may be an important moderating variable in the relationship between e-cigarette use and smoking cessation. However, few studies have focused specifically on treatment-seekers, a group that may differ in important ways from smokers in the general population. This study looks at the relationship between e-cigarette use frequency and abstinence among a sample of treatment-seeking tobacco users.

METHODS: Seven-month follow-up survey data from N=2760 treatment-seeking tobacco users who utilized statewide tobacco quitlines in three states were used to assess the relationship between 30-day point prevalence abstinence and e-cigarette use frequency at follow-up. E-cigarette use was examined in two ways. First, we looked at any use in the past 30days versus no use. Additionally, past 30-day e-cigarette use frequency was categorized into four groups: 0days, 1-5days - infrequent, 6-29days - intermediate, 30days - daily. Logistic regression models were constructed predicting 30-day point prevalence tobacco abstinence.

RESULTS: Both infrequent (AOR=0.35; CI=0.20-0.59) and intermediate (AOR=0.50; CI=0.32-0.80) past 30-day e-cigarette use were associated with lower rates of tobacco abstinence versus no past 30-day use. However, daily e-cigarette users (AOR=1.16; CI=0.71-1.70) had similar 30-day abstinence when compared to non-users.

CONCLUSIONS: Results from this study of treatment-seekers support findings from studies of general population tobacco users that suggest frequency of e-cigarette use is an important moderating variable in the relationship between e-cigarette use and tobacco cessation. Future studies should employ more refined measures of e-cigarette use.