Electronic Cigarette Use

The overarching goal of this research is to determine the most effective approach for helping dual users of cigarettes and electronic nicotine delivery systems (ENDS) quit smoking. 500 participants will be enrolled and can expect to be on study for 12 months.

Gender and sexual minority adults in Bangladesh experience high levels of stigma-related stress. Acute stress can trigger strong, affect-driven urges to smoke, vape, or engage in stress-attributed eating. These urges can rise and fall within minutes to hours, operating outside the reach of conventional clinic-based interventions delivered days or weeks later. This pilot micro-randomized trial (MRT) evaluates whether delivering a brief, culturally adapted support message via smartphone during moments of high self-reported stress reduces the intensity of the urge for the participant's pre-specified target behaviour, relative to no message. Over a 24-day period, 115 participants will be scheduled for up to 5 ecological momentary assessments (EMA) per day. Whenever a participant reports an acute stress level of 5 or higher (0 to 10 scale) and satisfies pre-specified privacy, safety, behavioural, and spacing criteria, the app randomizes with probability 0.5 to deliver either a brief support message or no message. By contributing multiple randomized decision points over time, each participant serves as their own micro-control. The primary outcome is the intensity of the urge for the participant's pre-specified target behaviour, measured 45 to 60 minutes after randomization. An exploratory urge assessment is also collected 10 minutes after randomization; comparing the two time points will help establish whether the support message's effect is immediate, delayed, or both, and will inform the choice of follow-up window for a future, fully powered trial. Prior to trial launch, all EMA items, message content, notification logic, and digital safety protocols will be developed and tested with community members, reviewed by a Community Advisory Board, and locked. As a pilot optimization trial, its objectives are to estimate the short-term causal effect of the prompt, to identify the contexts in which that effect is larger or smaller, and to establish whether momentary assessment and just-in-time intervention research can be delivered safely, privately, and acceptably in this high-stigma setting. The study does not evaluate long-term behavioural maintenance and does not claim to address the underlying structural stigma and discrimination that produce minority stress.

In this project, after systematically developing electronic nicotine delivery systems (ENDS) pictorial health warning labels (HWLs), a proven clinical lab model will be used to examine and test their effect when these are placed on the ENDS device on a variety of subjective (e.g. satisfaction, harm perception, nicotine dependence, intention to quit) and objective outcomes (e.g. plasma nicotine, puff topography) in young adults.

The purpose of this study is to determine the impact of tetrahydrocannabinol (THC) administration on motivational, subjective, and physiological effects of electronic cigarettes. The study's goals are to test demand for e-cigarettes, tobacco craving, affect, heart rate, blood pressure, expired breath carbon monoxide, and cognitive performance. Researchers will compare multiple doses of THC and a placebo in participants who smoke e-cigarettes and either smoke or vape THC in the laboratory.

The use of electronic nicotine delivery systems (ENDS; e-cigarettes) has reached epidemic levels among young people in the United States (US). ENDS heat and vaporize a nicotine-containing liquid to produce an inhalable aerosol mist. While generally considered less harmful than combustible cigarettes, ENDS use exposes users to dependence-producing nicotine and respiratory and cardiovascular toxicants such as aldehydes. Flavor is a major factor in getting young people to use ENDS, thus limiting flavors to menthol and tobacco for prefilled cartridge ENDS "pod mods" was the first major action taken by the FDA to reduce the spread of ENDS among young people. Menthol flavor, however, can present a potential risk given its increasing popularity among young people in the US, and its puffing and nicotine-enhancing properties. Yet, the extent of menthol's ability to affect users' experience and puffing patterns, and how these affect dependence, exposure to toxicants, and clinical outcomes continue to be understudied. Such evidence will be critical to the FDA's ability to set further regulatory standards to reduce ENDS potential harm. The investigators will conduct a 2x2 (pre-post x menthol vs. tobacco flavor) crossover clinical lab study. The investigator will recruit current/past month ENDS users (n=250, 21-35 yrs), who will attend two sessions and use their ENDS once with menthol and once with tobacco flavors. The proposed studies will answer two key regulatory questions consistent with FDA's focus on the role of flavor in tobacco products' addiction and toxicity; 1) compared to tobacco flavor, does menthol carry additional risk by enhancing puffing, abuse liability, and toxicant exposure in ENDS users, and; 2) is this effect more pronounced among high dependence compared to other users. Other outcomes such as harm perception, satisfaction, clinical responses, intention to use or quit, and group comparisons such as according to race, and sex will allow the FDA a comprehensive assessment of the pros and cons of regulating mentholated ENDS for different segments of the society. Such evidence will help advance FDA regulatory policies with the potential to reduce ENDS harm.

Electronic nicotine delivery systems (ENDS) are used by millions of Americans, however their long-term health effects are unknown. This research proposal will quantify the effects of long-term ENDS use on validated and novel biomarkers of cardiovascular and pulmonary disease and how they are influenced by use heaviness, age, body weight, and co-use of other products. This study will produce the most informative evidence to date on how long-term ENDS use affects cardiovascular and pulmonary health.

The use of electronic nicotine delivery systems, or e-cigarettes - colloquially referred to as "vaping" - in the United States has increased exponentially since their introduction to the US market in 2007. Prevalence of ever and current e-cigarette use is highest among teenagers and young adults with 16-28% of this population having reported vaping. While the majority of e-cigarette users are current tobacco smokers, 32.5% of current e-cigarette users are never- or former-smokers, representing a growing population of young adults who exclusively vape. While e-cigarettes have been marketed as a safer alternative to tobacco cigarettes, clinical studies examining these claims are limited. Cardiovascular disease (CVD) is the primary cause of premature death among tobacco cigarette smokers and reductions in vascular endothelial function, a significant predictor of future CVD, are detectible in otherwise healthy young adults who smoke. Despite the explosion in e-cigarette use among young adults, the health effects - especially the effects on mechanisms of vascular function - of these devices remain relatively unexplored. The purpose of this study is to directly asses the mechanistic role of inflammation in this dysfunction.

This prospective study assesses the pulmonary and cardiovascular effets of vaping in adult electronic cigarette users with biannual visits and a 5-year follow-up.