Electronic Cigarette Use Research Articles

Qualitative study of the use of electronic cigarettes in university students

Objective: The purpose of this research was to determine the level of knowledge, beliefs, perception, and practices associated with consuming electronic cigarettes among university students. Materials and methods: A qualitative study of phenomenological type and from primary sources was carried out in the period of May-August of the year 2019 at the private university Pontificia Universidad Católica Madre y Maestra (PUCMM) and the public university Universidad Autónoma de Santo Domingo (UASD), Santiago campus, Dominican Republic. The data collection method was done through interviews, which the interviewers recorded. Each student interviewed signed an informed consent certifying that they answered voluntarily each question asked by the interviewer. The sample consisted of 53 interviews, 48 individuals, and five focus groups. Interviews were done until reaching the saturation point of each question, which is when all the answers became repetitive. Results: University students’ knowledge regarding electronic cigarettes (EC) is poor. Knowledge regarding its mechanism, parts, substances, and possible complications to one’s health, is scarce both in PUCMM and the UASD, but this is more notable at the public university. Additionally, many perceive EC as an alternative to tobacco use, the former, as per our study population, having a variety of flavors, a pleasant smell, being attractive, practical, and capable of offering relaxation. Regarding the attitude towards the device, PUCMM exhibits a higher level of rejection regarding its use. It is essential to mention that most interviewees were once users of EC. However, they do not recommend it to a great extent since they assume that it can cause harm and be addictive, although to a lesser extent than conventional cigarettes. The population most susceptible to its use are young people, including minors and the male gender, although females have been significantly increasing its use. Similarly, it was possible to appreciate the influences that greatly evoke the younger population’s consumption, including social networks, family, friends, and the surrounding environment. Conclusion: We concluded that university students have insufficient knowledge regarding electronic cigarettes, both in their mechanism, substances, and health complications. Most see electronic cigarettes as smoking devices with a pleasant smell, which can be very attractive to users. It was possible to observe the critical role played by social influences on the use of the device, promoted by social networks and close relationships. Another problem in current society is the use of CE in minors. According to the results, there is a great need for intervention and education, mainly among the younger generation.

An Evaluation of the Contextual Factors Associated With the Use of Either Tobacco or Electronic Cigarettes in Individuals Who Dual Use.

Little is known about patterns of dual use of tobacco and electronic cigarettes (e-cigarettes), especially regarding the factors that lead people to choose either product in particular situations. Identifying contextual factors that are associated with product use would enhance understanding of the maintenance of dual product use. Individuals who dual use (N = 102) completed ecological momentary assessment surveys via text message regarding the recent use of tobacco and e-cigarettes for 2 weeks. Product legality, availability, craving, the presence of other people who smoke/vape, and social disapproval were assessed. Data were analyzed using hierarchical logistic regression to identify factors associated with the likelihood of tobacco versus e-cigarette use. Contexts associated with increased likelihood of using tobacco rather than e-cigarettes included being in the presence of other people who smoke (odds ratio [OR] = 3.50, p < .0001) and experiencing elevated tobacco cigarette craving (OR = 3.51, p < .0001). Decreased likelihood of tobacco over e-cigarette use was associated with smoking restrictions (OR = 0.26, p = .003), the presence of other people who vape (OR = 0.38, p < .001), and experiencing elevated e-cigarette craving (OR = 0.23, p < .0001). The legality of e-cigarettes, social disapproval, and the availability of the alternative product were not significantly associated with the use of one product over the other. An individual difference score of relative tobacco (vs. e-cigarette) use pattern did not significantly moderate these effects. This study provided essential information regarding behavioral patterns of dual use, which informs our understanding of people who dual use. Contexts such as smoking restrictions, craving, and social context significantly differentiated between the use of tobacco and e-cigarettes. This suggests product-specific motivations for dual use of tobacco and e-cigarettes in people who use both. This study assessed the relationship between momentary contextual factors and dual use in a nationally recruited sample of people who dual use. Assessments of dual use in daily life provided novel information regarding patterns of dual use as well as differential use-motivations for each product. This information will be essential to build a theoretical framework of dual use of tobacco and e-cigarettes.

Prevalence and factors associated with adolescents’ use of electronic cigarettes and hookahs in Pamplona: Emtamplona Study

ABSTRACT Background Electronic cigarettes, hookahs, or water pipes are new forms of tobacco consumption, these alternatives are becoming popular in the adolescent and young adult population. Objective To determine the prevalence and factors associated with the usage of electronic cigarettes and hookahs in Colombian adolescents. Materials and Methods Secondary analysis of data from one study aimed to determine the prevalence of traditional cigarette use (Emtamplona Study). The adolescents were considered consumers if he/she claimed to have consumed at least one cigarette or used a hookah and/or electronic cigarette during the last 30 days. A self-administered and anonymous questionnaire was answered by 812 adolescents aged 14 ± 2 years (438 women). Results The prevalence of electronic cigarette and hookah use was 1.8% (95%CI 0.9%–2.7%) and 2.8% (95%CI 1.8%–4.1%), respectively. A logistic regression analysis showed that traditional cigarette consumption was associated (OR 10.46, 95%CI 3.64–30.97) with electronic cigarette use. On the other hand, being in sixth-seventh grade (OR 5.19 95%CI 1.08–25.01) and belonging to a private school (OR 10.54 95%CI 3.95–28.13), smoking (OR 15.38 95%CI 3.45–68.62) was associated with hookah use. Conclusions Electronic cigarette and hookah use among these adolescents is low; however, public health strategies are important to control tobacco consumption.

Ovarian toxicity of e-cigarette liquids: Effects of components and high and low nicotine concentration e-cigarette liquid in vitro.

Electronic cigarette use has become increasingly popular, with potential consequences for reproductive health. We aimed to investigate the effects of different components of e-liquid on the ovary and compare the impact of low nicotine concentration e-liquids (LN e-liquids) and high nicotine concentration e-liquids (HN e-liquids) on ovarian toxicity. A total of 378 rat ovaries were divided into seven groups, including control (no intervention), nicotine (0.05 mg/mL), flavoring (0.25 μL/mL), propylene glycol (PG) (2.5 μL/mL), vegetable glycerin (VG) (2.0 μL/mL), LN e-liquid (0.05 mg nicotine + 0.25 μL flavoring + 2.5 μL PG + 2.0 μL VG + 0.25 μL distilled water/mL medium) and HN e-liquid groups (0.05 mg nicotine + 0.05 μL flavoring + 0.5 μL PG + 0.4 μL VG + 0.05 μL distilled water/mL medium). After three hours of in vitro culture, ovarian morphology, oxidation levels [superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA)], and apoptosis levels [factor related apoptosis (Fas), Cyt-c, Caspase-9, Caspase-3] were analyzed. Our findings indicate that nicotine has limited impact on the ovary, while flavoring, PG, and VG all cause ovarian damage including morphological damage, disruption of oxidative balance and promotion of apoptosis, with VG having the most significant effect. Moreover, LN e-liquids may lead to more severe ovarian damage than HN e-liquids at an equal intake of total nicotine. Our study highlights that in e-liquid formula, nicotine has a limited effect on the ovaries, but flavoring, PG, and VG all cause damage to the ovaries, with VG the most damaging. At a consistent level of total nicotine intake, e-liquids with low nicotine concentrations cause more damage to the ovaries than those with high nicotine concentrations. These findings contribute to a better understanding of the impact of e-liquids on ovarian health and have important implications for public health policy.

Brief report: Characterization of electronic cigarette use among patients of a comprehensive cancer center.

We provide an initial characterization of e-cigarette use among adult cancer patients. Data were collected between November 2020 and August 2022 at a comprehensive cancer center. Relatively few (4.59%) of the assessed patients (n = 47,117) reported ever using e-cigarettes. Over one-third of current e-cigarette users reported being current combustible cigarette users. These data suggest that e-cigarette use is uncommon but associated with other tobacco use among adult cancer patients. This is among the first comprehensive surveys of adult cancer patient e-cigarette use that details the types of e-cigarette and other tobacco products used by this population.

Influencing factors for electronic cigarette use among Chinese adolescent students: a Meta-analysis

Objective: To explore the influencing factors of electronic cigarette use among adolescent students in China. Methods: We searched CNKI, Database of Chinese sci-tech periodicals (VIP), Wan-fang database, PubMed, Web of Science and ScienceDirect for potentially relevant articles published from the inception to March 20th, 2023. The Metagen package in R was used for Meta-analysis. Results: A total of 19 publications with a sample size of 5 336 017 were identified. The results showed that electronic cigarette use among Chinese adolescent students was associated with gender (OR=2.41, 95%CI: 2.03-2.86), close friends smoking (OR=3.02, 95%CI: 2.08-4.39), current smoking (OR=11.26, 95%CI: 4.35-29.18), friends using electronic cigarettes (OR=5.19, 95%CI: 2.01-13.38), thinking smoking makes young people look more attractive (OR=2.00, 95%CI: 1.35-2.97), type of school (OR=2.10, 95%CI: 1.59-2.78), thinking smoking makes people feel more comfortable in social situations (OR=3.58, 95%CI: 2.99-4.28), other tobacco use (OR=5.53, 95%CI: 3.33-9.20), and ever experimented with cigarette use (OR=9.32, 95%CI: 4.38-19.80). Conclusion: The influencing factors for electronic cigarette use among adolescent students in China include gender, close friends smoking, current smoking, friends using electronic cigarettes, thinking smoking makes young people look more attractive, type of school, thinking smoking makes people feel more comfortable in social situations, other tobacco use, and ever experimented with cigarette use.

What Substances Are Adolescents Vaping? Estimating Nicotine-Specific and Cannabis-Specific Vaping from US National Youth Surveys

Background Youth use of electronic cigarettes (“e-cigarettes”) is an ongoing concern. Vaping is usually assumed to be of nicotine, but survey responses may also include vaping of non-nicotine substances (particularly cannabis), which can impose different risks. The current study quantifies the proportions of nicotine-specific and cannabis-specific vaping among adolescents. Methods Data from the Monitoring the Future (MTF) 2021 survey were analyzed with respect to the substance vaped: nicotine, cannabis, or flavoring only. Past-30-day (P30D) nicotine-specific vaping (exclusively, or also having vaped other substances) and cannabis-specific vaping were calculated. Results were also broken down by grade level, cigarette smoking history (current, former, or never), and frequency of e-cigarette use (<20 vs. 20+ days in P30D). Results Among 4706 P30D e-cigarette users, 84.2% vaped nicotine; the remaining 15.8% reported not vaping any nicotine in P30D. Cannabis vaping was reported by 48.4% of P30D vapers. Vaping both nicotine and cannabis in P30D was more common in current and former smokers than in never-smokers, and in frequent vapers (of any substance). Conversely, never-smokers were more commonly vaping cannabis but not nicotine, compared to current and former smokers. Supplementary NYTS 2022 analyses were consistent with these findings. Conclusions A notable proportion of self-reported P30D vapers reported not vaping nicotine; nearly half vaped cannabis. Capturing the variety of substances used in vaping devices is imperative for accurate public health surveillance of both nicotine and cannabis vaping among US adolescents, considering their different respective harms and regulatory frameworks.

Vaping among young people-Our best defence is self-defence.

Use of electronic cigarettes (e-cigarettes or 'vapes') has risen rapidly among young Australians in recent years. To combat this, on 2 May 2023, the Albanese Government announced a suite of reforms to reduce the desirability and accessibility of e-cigarettes to young people-including a ban on disposable e-cigarettes, restricting flavours, colours and nicotine content and requiring pharmaceutical-like packaging. While many have welcomed this announcement, the efficacy of such reforms in reducing the availability of e-cigarettes to young people remain to be seen, particularly given the current prescription-only model has done little to curb youth vaping. We argue that, in an uncertain landscape where e-cigarettes will likely remain accessible and desirable to young people, it is critical that we also upskill, empower and arm our young people with the skills, resilience, resources and knowledge to make informed and positive health decisions so that: (i) fewer young people opt to take up vaping (primary prevention); and (ii) among those who already do vape, more seek help earlier on to reduce or cease their use before dependency develops (secondary prevention). Schools are an ideal setting for the delivery of these programs, where they can be delivered en masse, integrated into existing alcohol and other drug programs and aligned with school curricula. Skills-based school prevention programs have demonstrated significant and sustained reductions in drug-related harms up to 7 years post-intervention. For as long as vapes remain widely available, desirable and purposefully marketed towards young people, we believe our best defence is self-defence.

Biomarkers of exposure in urine of active smokers, non-smokers, and vapers

The exposure to smoking related products has been evaluated through urine illness risk marker determination through the analysis of urine samples of smokers and vapers. Biomarkers and their metabolites such as N-acetyl-S-(2-cyanoethyl)-L-cysteine (CEMA), N-acetyl-S-(3,4-dihydroxybutyl)-L-cysteine (DHBMA), N-acetyl-S-[1-(hydroxymethyl)-2-propen-1-yl)-L-cysteine (MHBMA), N-acetyl-S-(3-hydroxypropyl)-L-cysteine (3HPMA), 2R-N-acetyl-S-(4-hydroxybutan-2-yl)-L-cysteine (HMPMA), and N-acetyl-S-(3-carboxy-2-propyl)-L-cysteine (CMEMA) together with nicotine and cotinine were identified and quantified by LC-HRMS and LC-MS/MS, and data found normalized to the creatinine level. One hundred two urine samples were collected from smokers, non-smokers, and vapers, spanning an age range from 16 to 79 years. Results obtained showed that CEMA was only detected in urine samples from smokers and MHBMA was in the same order of magnitude in all the urine samples analyzed. HMPMA was found in the urine of vapers at the same order of concentration as in non-smokers. 3HPMA in vapers was lower than in the urine of smokers, presenting an intermediate situation between smokers and non-smokers. On the other hand, DHBMA in vapers can reach similar values to those found for smokers, while CMEMA shows concentrations in the urine of vapers higher than in the case of non-smokers and traditional smokers, requiring new research to link this metabolite to the use of electronic cigarettes and possible alternative metabolomic routes. In general, this study seems to verify that traditional smoking practice constitutes a major source of carcinogenic chemicals compared with substitutive practices, although those practices are not free of potential harm.Graphical abstract

Electronic cigarette use and cigarette smoking associated with inadequate sleep duration among U.S. young adults

ObjectiveNicotine use can influence inadequate sleep, but less is known about the associations of exclusive and dual use of electronic cigarettes (e-cigarettes) with combustible cigarettes in U.S. young adults. This study assessed the associations between current exclusive e-cigarette use, exclusive cigarette smoking, and dual e-cigarette and combustible cigarette use and inadequate sleep duration among U.S. young adults. MethodsWe performed a secondary analysis of 2020 Behavioral Risk Factor Surveillance System (BRFSS) data including 13,978 U.S. young adults ages 18–24 years. Inadequate sleep duration was assessed categorically using the National Sleep Foundation's age-specific recommendations that define <7 h as inadequate sleep. Weighted logistic regression models were performed while adjusting for participants' sex, race/ethnicity, education level, annual household income level, body mass index, current physical activity, mental health status, disability status, current alcohol use, and current smokeless tobacco use. ResultsConcerning use patterns, 11.8% of young adults were exclusive e-cigarette users, 4.7% were exclusive cigarette smokers, and 3.8% were dual e-cigarette and combustible cigarette users. Exclusive e-cigarette users (adjusted odds ratio [AOR] = 1.41, 95% confidence interval [CI] = 1.16–1.72), exclusive cigarette smokers (AOR = 1.63, 95%CI = 1.22–2.18), and dual product users (AOR = 2.03, 95%CI = 1.44–2.86) were at increased odds of having inadequate sleep duration compared to non-users, while adjusting for the covariates. Additionally, dual product users were at increased odds (AOR = 1.52, 95%CI = 1.06–2.19) of reporting inadequate sleep duration compared to exclusive e-cigarette users, while adjusting for the covariates. ConclusionsCurrent e-cigarette and cigarette use may influence inadequate sleep among U.S. young adults. Tobacco cessation efforts may encourage increased sleep health.

Electronic Cigarette Harms: Aggregate Evidence Shows Damage to Biological Systems.

Evidence of the harms of e-cigarettes has been unfolding slowly and has been documented in many reviews and reports worldwide. A narrative review of new evidence is presented since, as research has continued, newly aggregated evidence of the dangers of electronic cigarettes on the brain, heart, and lungs is vital to inform decisions on restricting the use of e-cigarettes. Several biomedical research databases were searched for electronic cigarette health effects, emphasizing reviews, systematic reviews, and meta-analyses. Over 50 review studies, primarily in 2022 and 2023, illustrate some of the latest information on e-cigarette harms. Results show studies of respiratory, neurological, and cardiovascular effects. Researchers call for expanding studies through new methods to elaborate on initial findings of multiple harms emerging in clinical investigations. Since the use of electronic cigarettes for adult cessation is not sanctioned in most countries, it is clear that health authorities see significant costs to the health of the general population if the promotion and use of electronic cigarettes occur worldwide. Regulatory action to control electronic cigarettes should consider the substantial evidence of electronic cigarette harm.

Nicotine flux as a powerful tool for regulating nicotine delivery from e-cigarettes: Protocol of two complimentary randomized crossover clinical trials.

Electronic cigarette (EC) use has increased rapidly in the last decade, especially among youth. Regulating nicotine delivery from ECs could help curb youth uptake and leverage EC use in harm reduction yet is complicated by varying device and liquid variables that affect nicotine delivery. Nicotine flux, the nicotine emission rate, is a parameter that incorporates these variables and focuses on the performance rather than the design of an EC. Nicotine flux therefore could be a powerful regulatory tool if it is shown empirically to predict nicotine delivery and subjective effects related to dependence. This project consists of two complementary clinical trials. In Trial I, we will examine the relationship between nicotine flux and the rate and dose of nicotine delivery from ECs, hence, impacting abuse liability. It will also examine the extent to which this relationship is mediated by nicotine form (i.e., freebase versus protonated). At Yale School of Medicine (YSM), study participants will puff EC devices under conditions that differ by flux and form, while arterial blood is sampled in high time resolution. In Trial II, we will assess the relationship between nicotine flux, form, and subjective effects. At the American University of Beirut (AUB), participants will use EC devices with varying nicotine fluxes and forms, while dependency measures, such as the urge to use ECs, nicotine craving, and withdrawal symptoms, will be assessed. We will also monitor puffing intensity and real-time exposure to toxicants. The protocol of Trial I and Trial II was approved by YSM and AUB IRBs, respectively. We will disseminate study results through peer-reviewed publications and conference presentations. NCT05706701 for Trial I and NCT05430334 for Trial II.

How young people in Aotearoa perceive vaping and the associated oral health risks.

The use of electronic cigarettes (EC) among young people has escalated in Aotearoa and in other jurisdictions where they are available commercially. The rise in vaping among young people for lifestyle reasons rather than for smoking cessation is of concern, given the growing evidence of the harmful effects of vaping. Specifically, there is little known about how young people in Aotearoa perceive the effect of vaping on their oral health. This study aims to explore how young people in Aotearoa perceive risks of vaping on oral health. A cross-sectional online survey (n=237) was conducted to explore young people's (16-24 years) perceptions, current practices and attitudes regarding vaping and oral health. Although most participants understood that vaping posed risks to their general health, they reported lower levels of perceived risk of vaping on oral health. Current vapers held significantly lower perceptions of both the addictiveness and harms associated with vaping. Participants reported that oral health professionals seldom asked them about their vaping status. Most participants were open to discussing with oral health professionals the effects of vaping on their oral health, suggesting that they would be less likely to vape if they knew it was bad for their oral health. The findings indicate that there is a need for improved information for young people communicating the potential oral health risks of vaping and that oral health professionals are a way to disseminate this information.

A Cross-Sectional Survey on Oral Nicotine Pouches: Characterizing Use-Motives, Topography, Dependence Levels, and Adverse Events.

Oral nicotine pouches (ONPs) contain a crystalized nicotine powder instead of tobacco leaves. ONPs come in a variety of flavors and are often marketed as "tobacco-free," but research on ONP use-motivations and related experiences is limited. This cross-sectional web-based survey collected self-report data on ONP use-characteristics (eg, frequency), brands and flavors used, use-motivations, dependence (Fagerström Test for Nicotine Dependence-Smokeless Tobacco [FTND-ST]), and ONP-related adverse events (AEs) experienced. The sample included 118 adults who reported current (past 30-day) ONP use. On average (SD), participants reported ONP use on 13 (6) days during the past month. Most participants (% of the sample) also reported the use of tobacco cigarettes (74%) and/or electronic cigarettes (53%) during the past month. Zyn (27%) and Lucy (19%) were the most currently used ONP brands with mint (23%) and tobacco (16%) as the most currently used flavors. The availability of preferred flavors was the most frequently reported (31%) ONP use-motivation. The sample demonstrated significant dependence levels (FTND-ST = 7, SD = 2). Reported AEs included mouth lesions (48%), upset stomach (39%), sore mouth (37%), sore throat (21%), and nausea (9%). Results should be interpreted in the context of study limitations, including using a relatively small and homogeneous online convenience sample. Acknowledging the limitations, this sample was deemed appropriate to include considering the novelty of the findings, the dearth of related research, and the necessity of examining foundational ONP use-characteristics (eg, topography, AEs); however, future research should consider recruiting larger and more generalizable samples. The availability of preferred flavors was a key ONP use-motivation in this sample. Mint and tobacco were the most currently used flavors, with Zyn and Lucy being the most currently used ONP brands. Participants reported dependence and a substantial number of ONP-related AEs. Nationally representative surveys should investigate ONP use along with outcomes included in the current study (eg, AEs) to inform ONP surveillance and policy development efforts. This study is among the first to assess reasons for initiating/maintaining ONP use as well as other relevant use-experiences (eg, AEs, dependence). These results highlight the role of flavors and nicotine dependence in ONP use, which are important considerations for informing ONP regulations.

Association of dual use of cigarettes with obstructive sleep apnea assessed by the STOP-Bang score.

Although previous studies have addressed the association between smoking and obstructive sleep apnea (OSA), there are few studies on the association between electronic cigarette use and OSA. Thus, we aimed to evaluate the association between the dual use of electronic and conventional cigarettes and OSA. Data from 7350 participants of the 2019-2021 Korean National Health and Nutrition Examination Survey were analyzed in this population-based study. The STOP-Bang score was calculated using eight items: snoring, tiredness, observed apnea, high blood pressure, body mass index, age, neck circumference, and sex. The main independent variable was smoking behavior. A multiple logistic regression analysis was performed. Subgroup analysis was conducted to analyze the association between smoking behavior in detail and OSA, and stratified analyses were additionally performed. Of the 7350 participants, 417 (5.7%) had a high risk of OSA, according to the STOP-Bang score. Compared to the non-smoker group, the dual user group had a 2.46-fold increase in the odds of OSA (adjusted odds ratio, AOR = 2.45; 95% CI: 1.04-5.79). Current non-smokers who were dual users in the past had increased odds of having OSA (AOR=3.61; 95% CI: 1.32-9.92). In the stratified analyses, dual cigarette use was significantly associated with OSA in females and those with a low physical activity level. Dual users and cigarette-only users had an increased probability of developing OSA. Even if they are not currently smoking or vaping, individuals who were dual users in the past were associated with a higher risk of OSA. The association between dual cigarette use and OSA was more pronounced in females and those with a low physical activity level. While intervening for obstructive sleep apnea or investigating risk factors, new smoking methods such as vaping and dual use should be considered along with conventional smoking.

Electronic cigarette exposure disrupts airway epithelial barrier function and exacerbates viral infection.

The use of electronic cigarettes (e-cigs), especially among teenagers, has reached alarming and epidemic levels, posing a significant threat to public health. However, the short- and long-term effects of vaping on the airway epithelial barrier are unclear. Airway epithelial cells are the forefront protectors from viruses and pathogens. They contain apical junctional complexes (AJCs), which include tight junctions (TJs) and adherens junctions (AJs) formed between adjacent cells. Previously, we reported respiratory syncytial virus (RSV) infection, the leading cause of acute lower respiratory infection-related hospitalization in children and high-risk adults, induces a "leaky airway" by disrupting the epithelial AJC structure and function. We hypothesized chemical components of e-cigs disrupt airway epithelial barrier and exacerbate RSV-induced airway barrier dysfunction. Using confluent human bronchial epithelial (16HBE) cells and well-differentiated normal human bronchial epithelial (NHBE) cells, we found that exposure to extract and aerosol e-cig nicotine caused a significant decrease in transepithelial electrical resistance (TEER) and the structure of the AJC even at noncytotoxic concentrations. Western blot analysis of 16HBE cells exposed to e-cig nicotine extract did not reveal significant changes in AJC proteins. Exposure to aerosolized e-cig cinnamon or menthol flavors also induced barrier disruption and aggravated nicotine-induced airway barrier dysfunction. Moreover, preexposure to nicotine aerosol increased RSV infection and the severity of RSV-induced airway barrier disruption. Our findings demonstrate that e-cig exposure disrupts the airway epithelial barrier and exacerbates RSV-induced damage. Knowledge gained from this study will provide awareness of adverse e-cig respiratory effects and positively impact the mitigation of e-cig epidemic.NEW & NOTEWORTHY Electronic cigarette (e-cig) use, especially in teens, is alarming and at epidemic proportions, threatening public health. Our study shows that e-cig nicotine exposure disrupts airway epithelial tight junctions and increases RSV-induced barrier dysfunction. Furthermore, exposure to aerosolized flavors exaggerates e-cig nicotine-induced airway barrier dysfunction. Our study confirms that individual and combined components of e-cigs deleteriously impact the airway barrier and that e-cig exposure increases susceptibility to viral infection.

Sex-specific lung inflammation and mitochondrial damage in a model of electronic cigarette exposure in asthma.

The prevalence of electronic cigarette (EC) use among adult with asthma has continued to increase over time, in part due to the belief of being less harmful than smoking. However, the extent of their toxicity and the involved mechanisms contributing to the deleterious impact of EC exposure on patients with preexisting asthma have not been delineated. In the present project, we tested the hypothesis that EC use contributes to respiratory damage and worsening inflammation in the lungs of patients with asthma. To define the consequences of EC exposure in established asthma, we used a mouse model with/without preexisting asthma for short-term exposure to EC aerosols. C57/BL6J mice were sensitized and challenged with a DRA (dust mite, ragweed, Aspergillus fumigates, 200 µg/mL) mixture and exposed daily to EC with nicotine (2% nicotine in 30:70 propylene glycol: vegetable glycerin) or filtered air for 2 wk. The mice were evaluated at 24 h after the final EC exposure. After EC exposure in asthmatic mice, lung inflammatory cell infiltration and goblet cell hyperplasia were increased, whereas EC alone did not cause airway inflammation. Our data also show that mitochondrial DNA (mtDNA) content and a key mtDNA regulator, mitochondrial transcription factor A (TFAM), are reduced in asthmatic EC-exposed mice in a sex-dependent manner. Together, these results indicate that TFAM loss in lung epithelium following EC contributes to male-predominant sex pathological differences, including mitochondrial damage, inflammation, and remodeling in asthmatic airways.NEW & NOTEWORTHY Respiratory immunity is dysregulated in preexisting asthma, and further perturbations by EC use could exacerbate asthma severity. However, the extent of their toxicity and the involved mechanisms contributing to the deleterious impact of EC exposure on patients with preexisting asthma have not been delineated. We found that EC has unique biological impacts in lungs and potential sex differences with loss of TFAM, a key mtDNA regulator, in lung epithelial region from our animal EC study.

Use of Electronic Cigarettes among Secondary School Students and their Association with Depressive Symptoms: Findings from a National Secondary School Survey in Thailand

Objective: to describe: 1) the prevalence of electronic cigarette use among Thai secondary school students, stratified by grade levels and sex; 2) the extent that depressive symptoms were associated with former and current use of electronic cigarette.Material and Methods: We conducted a cross-sectional study from secondary school students in Thailand in years 7, 9, and 11 of the 12-years educational system. We randomly sampled 113 schools in 21 provinces and Bangkok, randomly sampled classrooms in the school, and invited all students present in the sampled classrooms to participate in the study. All data were collected using self-administered questionnaires. We measured depressive symptoms using the Patient Health Questionnaire-2 (PHQ-2) instrument, and measured electronic cigarette use with adapted versions of existing instruments. Data analyses included descriptive statistics and logistic regression analyses with adjustment for sampling weights.Results: A total of 23,659 students responded and provided adequately completed questionnaires. Approximately 12.3% of the participants reported a lifetime history of using electronic cigarette. Electronic cigarette use was more common among males and older students. There seemed to be a threshold in the association between the level of depressive symptoms and ever vs. never use of electronic cigarette, and the association was strongest at a PHQ-2 score of 6 vs. 0 (adjusted odd ratio (OR)=1.72; 95% confidence interval (CI)=0.98, 3.03). A similar association was found between current vs. former or never use of electronic cigarette and having a PHQ-2 score of 6 vs. 0 (adjusted OR=1.84; 95% CI=0.96, 3.52).Conclusion: We found associations between depressive symptoms and electronic cigarette use. However, limitations with regard to the lack of temporality, measurement issues, and lack of generalizability should be considered as caveats in the interpretation of the study findings.

E-cigarette vapor renders neutrophils dysfunctional due to filamentous actin accumulation

Electronic cigarette (e-cigarette) use continues to rise despite concerns of long-term effects, especially the risk of developing lung diseases such as chronic obstructive pulmonary disease. Neutrophils are central to the pathogenesis of chronic obstructive pulmonary disease, with changes in phenotype and function implicated in tissue damage. We sought to measure the impact of direct exposure to nicotine-containing and nicotine-free e-cigarette vapor on human neutrophil function and phenotype. Neutrophils were isolated from the whole blood of self-reported nonsmoking, nonvaping healthy volunteers. Neutrophils were exposed to 40 puffs of e-cigarette vapor generated from e-cigarette devices using flavorless e-cigarette liquids with and without nicotine before functions, deformability, and phenotype were assessed. Neutrophil surface marker expression was altered, with CD62L and CXCR2 expression significantly reduced in neutrophils treated with e-cigarette vapor containing nicotine. Neutrophil migration to IL-8, phagocytosis of Escherichia coli and Staphylococcus aureus pHrodo bioparticles, oxidative burst response, and phorbol 12-myristate 13-acetate-stimulated neutrophil extracellular trap formation were all significantly reduced by e-cigarette vapor treatments, independent of nicotine content. E-cigarette vapor induced increased levels of baseline polymerized filamentous actin levels in the cytoplasm, compared with untreated controls. The significant reduction in effector neutrophil functions after exposure to high-power e-cigarette devices, even in the absence of nicotine, is associated with excessive filamentous actin polymerization. This highlights the potentially damaging impact of vaping on respiratory health and reinforces the urgency of research to uncover the long-term health implications of e-cigarettes.

Chronic Electronic Cigarette Use and Atherosclerosis Risk in Young People: A Cross-Sectional Study-Brief Report.

Little is known whether electronic cigarettes (ECIG) increase vulnerability to future atherosclerotic cardiovascular disease. We determined, using an ex vivo mechanistic atherogenesis assay, whether proatherogenic changes including monocyte transendothelial migration and monocyte-derived foam cell formation are increased in people who use ECIGs. In a cross-sectional single-center study using plasma and peripheral blood mononuclear cells from healthy participants who are nonsmokers or with exclusive use of ECIGs or tobacco cigarettes (TCIGs), autologous peripheral blood mononuclear cells with patient plasma and pooled peripheral blood mononuclear cells from healthy nonsmokers with patient plasma were utilized to dissect patient-specific ex vivo proatherogenic circulating factors present in plasma and cellular factors present in monocytes. Our main outcomes were monocyte transendothelial migration (% of blood monocyte cells that undergo transendothelial migration through a collagen gel) and monocyte-derived foam cell formation as determined by flow cytometry and the median fluorescence intensity of the lipid-staining fluorochrome BODIPY in monocytes of participants in the setting of an ex vivo model of atherogenesis. Study participants (N=60) had median age of 24.0 years (interquartile range [IQR], 22.0-25.0 years), and 31 were females. Monocyte transendothelial migration was increased in people who exclusively used TCIGs (n=18; median [IQR], 2.30 [ 1.29-2.82]; P<0.001) and in people who exclusively used ECIGs (n=21; median [IQR], 1.42 [ 0.96-1.91]; P<0.01) compared with nonsmoking controls (n=21; median [IQR], 1.05 [0.66-1.24]). Monocyte-derived foam cell formation was increased in people who exclusively used TCIGs (median [IQR], 2.01 [ 1.59-2.49]; P<0.001) and in people who exclusively used ECIGs (median [IQR], 1.54 [ 1.10-1.86]; P<0.001) compared with nonsmoker controls (median [IQR], 0.97 [0.86-1.22]). Both monocyte transendothelial migration and monocyte-derived foam cell formation were higher in TCIG smokers compared with ECIG users and in ECIG users who were former smokers versus ECIG users who were never smokers (P<0.05 for all comparisons). The finding of alterations in proatherogenic properties of blood monocytes and plasma in TCIG smokers compared with nonsmokers validates this assay as a strong ex vivo mechanistic tool with which to measure proatherogenic changes in people who use ECIGs. Similar yet significantly less severe alterations in proatherogenic properties of monocytes and plasma were detected in the blood from ECIG users. Future studies are necessary to determine whether these findings are attributable to a residual effect of prior smoking or are a direct effect of current ECIG use.