Vaping and Smoking Withdrawal Project

The proposed research, which will systematically and comprehensively characterize the withdrawal among daily vapers compared to daily smokers of combustible cigarettes, filling critical gaps in the understanding of electronic nicotine delivery systems (ENDS) dependence/abuse liability and contributing to the development of therapies for tobacco/nicotine use, the leading preventable cause of death in the US.

Withdrawal is a key, multi-faceted component of tobacco/nicotine dependence. Because withdrawal symptoms are theorized to drive relapse, facets of withdrawal (e.g., craving, negative affect) are the targets of most current and emerging treatments. Despite the central importance of withdrawal, and a voluminous literature on withdrawal from combustible cigarette smoking, little is known about withdrawal from electronic nicotine delivery systems (ENDS). To overcome critical barriers to progress in the field, the first-ever prospective, controlled comparison of abstinence-induced withdrawal between ENDS vapers and cigarette smokers is proposed. Participants will be 160 established daily vapers (including former smokers and dual users who smoke occasionally), 160 established daily smokers (including former vapers and dual users who vape occasionally), and (for exploratory comparisons) 50 established daily dual users, who smoke and vape daily. Participants will complete two 4-hour lab visits; the order of the ad lib use visit and the abstinent visit (which follows 24 hours of abstinence) will be randomized across participants. To advance knowledge of ENDS withdrawal, state-of-the-science, multi-measure, multi-method assessments of key withdrawal facets (negative affect, craving, difficulty concentrating, restlessness, sleep, and appetite, as well as anhedonia/positive affect and somatic effects) will be employed. For each facet, the hypothesis that withdrawal magnitude is lower among vapers compared to smokers will be tested. To inform theory and intervention development, the behavioral significance of ENDS withdrawal will also be evaluated, testing the hypotheses that abstinence will increase the motivation to vape/smoke and this group difference will be accounted for (mediated) by vaper/smoker differences in one or more withdrawal facets. Exploratory analyses will examine whether group differences in withdrawal are accounted for (mediate) by differential nicotine exposure, explore the role of individual differences (e.g., sex, rate of nicotine metabolism, expectancies), and examine differences among sub-groups of vapers. The impact of this much-needed, detailed characterization of withdrawal from ENDS is enhanced by the inclusion of a comparator of great public health significance, cigarette smoking. In addition, by characterizing the specific withdrawal facets that drive motivation to vape/smoke, the proposed work will identify promising intervention targets for subsequent treatment development efforts.

Eligibility Criteria:
Inclusion Criteria:

* 6+ months of daily/near-daily nicotine vaping and/or cigarette smoking (to yield 160 vapers, 160 smokers, 50 dual users)
* 200+ ng/mL cotinine on a commercially-available quick screen

Current Exclusion Criteria:

* intention to quit daily/near-daily vaping/smoking in the next month
* current (2+ days out of the past 7) use of pipe tobacco, hookah/shisha, smokeless tobacco, dissolvable tobacco, nicotine pouches. For vaping group only, current (2+ days out of past 7) use of cigars, cigarillos, or filtered cigars that are filled with tobacco or a mix of tobacco and marijuana
* current use of any smoking cessation medication
* current severe substance dependence other than tobacco/nicotine (including cannabis; NIDA Modified ASSIST of 27+)
* current (past 2 weeks) suicidal ideation with intent and/or plan
* current antipsychotic medications or lifetime history of schizophrenia or bipolar disorder
* pregnancy (intake urine screen)

Original Exclusion Criteria that have been modified or eliminated:

* \>1 use in past month of tobacco/nicotine products other than ENDS and combustible cigarettes (modified 5/19/25 - see current exclusion criteria)
* alcohol: AUDIT \> 15 for males and \>13 for females (eliminated 7/25/23)
* current major depression (PHQ-9\>11) (eliminated 7/25/23)
* suicide risk (answer to question #9 on PHQ-9 is anything other than "Not at all") (modified 11/17/23 - see current exclusion criteria)