E-Cigarettes: Biomarkers of Exposure and the Development and Validation of a Research Toolkit

Electronic nicotine delivery systems (ENDS) have gained worldwide popularity. Even so, there is limited research on the potential effects of regular ENDS use on health. Moreover, little is known about ENDS dependence and studies are often limited by a lack of validated research tools. Current measures of ENDS dependence are adapted from cigarette dependence questionnaires and do not consider concepts unique to ENDS vaping. Similarly, there are currently no validated ENDS-related stimuli for use in the research of drug reward and addictive behaviors. This thesis therefore directly compared the urinary cotinine levels, a biomarker of nicotine exposure, in individuals who use ENDS exclusively, use ENDS in conjunction with smoking tobacco cigarettes (dual users), and smoke cigarettes exclusively. We found no significant differences in cotinine levels between genders [F(2,84)=0.46, p=0.636], and between participant groups [F(2,84)=0.12, p=0.892]. In exclusive ENDS users, individuals with higher levels of cotinine also reported shorter times before vaping after waking [r(21)=-0.46, p=0.028]. Additionally, this thesis developed and validated a questionnaire to assess ENDS dependence and a database of 120 ENDS-related image cues. Exploratory factors analysis reduced an initial pool of 28 ENDS dependence items to 15 that were included in the final ENDS Nicotine Dependence Questionnaire (ENDS-DQ). Further analyses found that the ENDS DQ has high internal consistency (Cronbach α=0.84), external validity, and test-retest reliability (ICC=0.87). Regarding the development of an ENDS-related cue database, findings from our preliminary and follow-up validation studies were consistent with one another and with literature. Desire-to-vape ratings of ENDS-related images were correlated with valence (r=0.55, p

Department dc:contributor.department

Pharmacology

Year dc:date.issued

2021

Author dc:creator

• Ng, Ginnie Wing Yan

Advisor dc:contributor.advisor

• Zawertailo, Laurie

• biomarkers
• dependence
• e-cigarette
• nicotine
• questionnaire
• stimuli

Statement dc:rights

• Attribution-NoDerivatives 4.0 International

Licence dc:rights.uri

• http://creativecommons.org/licenses/by-nd/4.0/

Handle dc:identifier.uri

http://hdl.handle.net/1807/106458

OAI identifier oai:identifier

oai:utoronto.scholaris.ca:1807/106458