Abstract
INTRODUCTION: It is important to understand the impact of vaping on biological processes such as sleep. To date this has only been examined using cross-sectional, retrospective surveys. This study addresses this knowledge gap by (1) investigating bidirectional relationships between sleep quality and nicotine vaping based on real-time and real-life data and (2) exploring how young adults think about sleep and vaping and their reactions to monitoring these constructs. METHODS: Thirty-five young adults (ages 18-25) daily e-cigarette users wore smartwatches 24/7 to assess sleep quality and completed ecological momentary assessments for 7 days. Linear mixed models examined (1) whether sleep quality in the prior night predicted vaping frequency, negative mood, and craving today and (2) whether today's vaping frequency predicted the quality of tonight's sleep. Thematic analysis was conducted on participants' open-ended responses to the follow-up survey to explore what they learned about their sleep and vaping through self-monitoring. RESULTS: A higher percentage of wake time after sleep onset predicted higher levels of negative mood (β = 3.9793, p = .0220) and craving for e-cigarettes (β = 3.0806, p = .0277). Greater vaping frequency predicted lower overall sleep quality (β = -0.2056, p = .0322) and more time in light sleep (β = -0.0011, p = .0296). The majority of participants reported that during the course of the study they learned that they had sleep problems and vaped more than they thought. CONCLUSIONS: The findings of this first real-time and real-life study support bidirectional relationships between sleep quality and nicotine vaping. Smartwatch and smartphone technology to track sleep and vaping influenced self-awareness and shows promise for future vaping cessation interventions. IMPLICATIONS: Limited research has been conducted looking at how vaping can influence sleep and how sleep can influence subsequent vaping among young adults. Data from real-time measures completed in real life showed that vaping interfered with sleep and that waking up more in the middle of the night increased negative affect and craving to vape the following day. Using the smartwatch and app to monitor sleep and vaping increased participants' awareness of these behaviors, which could be used to motivate vaping cessation.