How E-cigarettes and vaping can affect asthma in children and adolescents

Impact of electronic cigarettes (e-cigs) and heat-not-burn/heated tobacco products (HnB/HTP) on asthma and chronic obstructive pulmonary disease: a viewpoint of the Italian Society of Internal Medicine

The association of cigarette smoking with several severe and very severe diseases (oncological, cardiovascular, respiratory) which have dramatic epidemiological, medical, and financial impact, is a well-known public threat. Asthma and chronic obstructive pulmonary disease (COPD) are highly prevalent diseases in Italy, posing significant public health challenges. Tobacco smoking, a primary risk factor for COPD and a common asthma trigger, remains a critical preventable public health issue. While universally acknowledged that quitting smoking drastically reduces the risk of smoking-related health issues, a significant portion of smokers and patients find quitting challenging or undesirable, hence a need for new ways to deal with it. A worth considering alternative might be the switch to electronic cigarettes (e-cig), and heat-not-burn/heated tobacco products (HnB/HTP). Emerging evidence suggests potential benefits in asthma and COPD management when transitioning from traditional smoking to e-cigs or HnB devices. However, the effectiveness of these products in facilitating smoking cessation is still debated, alongside concerns about their role in promoting smoking initiation among non-smokers. Internists are among the physicians who most frequently assist patients with smoking-related diseases, and in this perspective they cannot avoid paying attention to the progressive diffusion of smoking products alternative to the traditional cigarette, and to the controversies with respect to their use. In this context, the Italian Society of Internal Medicine, also recognizing a growing need for clarity for healthcare providers, has undertaken a comprehensive analysis of existing literature to offer an informed perspective on the health impact of e-cigs and HnB/HTP on asthma and COPD.

Current perspective on e-cigarette use and respiratory outcomes: mechanisms and messaging

INTRODUCTION

There has been an increasing amount of research on the consequences of e-cigarette use for respiratory outcomes, which is significant for public health and respiratory medicine. We discuss recent findings and lay out implications for prevention and treatment.

AREAS COVERED

Based on literature searches using several databases (PubMed, Web of Science, Google Scholar) for keywords, including synonyms, 'e-cigarettes,' with 'pulmonary function,' 'oxidative stress,' and 'inflammation,' we review studies on acute effects of e-cigarette use for measures of pulmonary function and discuss selected laboratory studies on mechanisms of effect, focusing on processes with known relation to respiratory disease; oxidative stress and inflammation. We discuss available studies that have tested the effectiveness of communication strategies for prevention of e-cigarette use oriented to different audiences, including nonsmoking adolescents and adult smokers.

EXPERT OPINION

We conclude that the evidence presents a mixed picture. Evidence is found for adverse consequences of e-cigarette use on measures of lung function and two disease-related biological processes, sometimes but not always less than for cigarette smoking. How to best communicate these results to a complex audience of users, from younger susceptible adolescents to long-term adult smokers interested in quitting, is a question of significant interest and empirically validated communication strategies are greatly needed.

A systematic review and meta-analysis of e-cigarette use among cancer survivors

PURPOSE

We conducted a systematic review and meta-analysis to determine the use of e-cigarettes among cancer survivors, factors associated with their use, and prevalence of e-cigarette use as a quit attempt.

METHODS

We searched five electronic databases until June 2022. Two authors independently selected studies, appraised their quality, and collected data.

RESULTS

Twenty-three publications from eight data sources (national surveys) met our eligibility criteria. The pooled rate of lifetime e-cigarette use among cancer survivors was 15% (95% CI 6-27%); current use was 3% (95% CI 0-8%). Among survivors who currently used traditional cigarettes, 63% (95% CI 57-69%) also used e-cigarettes. The reported rates of weighted lifetime e-cigarette use differed between age groups (18-44 years, up to 46.7%; 45-64, up to 27.2%; ≥65, up to 24.8%). Nine publications reported factors associated with lifetime e-cigarette use (i.e., active use of traditional cigarettes; heavy drinking; poor mental health; younger age; being male, non-Hispanic White, or single; having less than high school education or income ≤$25,000 USD; and living in the South regions of the US or urban areas). E-cigarettes were used as a quit resource by 75% of survivors reporting dual use of electronic and traditional cigarettes (95% CI 63%, 85%).

CONCLUSION

More than two-thirds of survivors currently using traditional cigarettes also use e-cigarettes. Higher use rates of e-cigarettes were reported among young cancer survivors compared to older survivors. Future studies are needed to assess the impact of e-cigarettes on long-term health and improve screening of smoking behaviors.

IMPLICATIONS FOR CANCER SURVIVORS

Our study provides an overview of the prevalence of e-cigarette use and sociodemographic risk factors associated with e-cigarette use among cancer survivors. The findings can assist providers in supporting attempts to quit among cancer survivors.

Nicotine affects mitochondrial structure and function in human airway smooth muscle cells

Exposure to cigarette smoke and e-cigarettes, with nicotine as the active constituent, contributes to increased health risks associated with asthma. Nicotine exerts its functional activity via nicotinic acetylcholine receptors (nAChRs), and the alpha7 subtype (α7nAChR) has recently been shown to adversely affect airway dynamics. The mechanisms of α7nAChR action in airways, particularly in the context of airway smooth muscle (ASM), a key cell type in asthma, are still under investigation. Mitochondria have garnered increasing interest for their role in regulating airway tone and adaptations to cellular stress. Here mitochondrial dynamics such as fusion versus fission, and mitochondrial Ca2+ ([Ca2+]m), play an important role in mitochondrial homeostasis. There is currently no information on effects and mechanisms by which nicotine regulates mitochondrial structure and function in ASM in the context of asthma. We hypothesized that nicotine disrupts mitochondrial morphology, fission-fusion balance, and [Ca2+]m regulation, with altered mitochondrial respiration and bioenergetics in the context of asthmatic ASM. Using human ASM (hASM) cells from nonasthmatics, asthmatics, and smokers, we examined the effects of nicotine on mitochondrial dynamics and [Ca2+]m. Fluorescence [Ca2+]m imaging of hASM cells with rhod-2 showed robust responses to 10 μM nicotine, particularly in asthmatics and smokers. In both asthmatics and smokers, nicotine increased the expression of fission proteins while decreasing fusion proteins. Seahorse analysis showed blunted oxidative phosphorylation parameters in response to nicotine in these groups. α7nAChR siRNA blunted nicotine effects, rescuing [Ca2+]m, changes in mitochondrial structural proteins, and mitochondrial dysfunction. These data highlight mitochondria as a target of nicotine effects on ASM, where mitochondrial disruption and impaired buffering could permit downstream effects of nicotine in the context of asthma.NEW & NOTEWORTHY Asthma is a major healthcare burden, which is further exacerbated by smoking. Recognizing the smoking risk of asthma, understanding the effects of nicotine on asthmatic airways becomes critical. Surprisingly, the mechanisms of nicotine action, even in normal and especially asthmatic airways, are understudied. Accordingly, the goal of this research is to investigate how nicotine influences asthmatic airways in terms of mitochondrial structure and function, via the a7nAChR.

Current Approaches in the Multimodal Management of Asthma in Adolescents-From Pharmacology to Personalized Therapy

Asthma and adolescence are two sensitive points and are difficult to manage when they coexist. The first is a chronic respiratory condition, with frequent onset in early childhood (between 3 and 5 years), which can improve or worsen with age. Adolescence is the period between childhood and adulthood (12-19 years), marked by various internal and external conflicts and a limited capacity to understand and accept any aspect that is delimited by the pattern of the social circle (of the entourage) frequented by the individual. Therefore, the clinician is faced with multiple attempts regarding the management of asthma encountered during the adolescent period, starting from the individualization of the therapy to the control of compliance (which depends equally on the adverse reactions, quality of life offered and support of the close circle) and the social integration of the subject, communication probably having a more important role in the monitoring and evolution of the condition than the preference for a certain therapeutic scheme. Current statistics draw attention to the increase in morbidity and mortality among children with bronchial asthma, an aspect demonstrated by the numerous hospitalizations recorded, due either to an escalation in the severity of this pathology or to faulty management. The purpose of this article is to review the delicate aspects in terms of controlling symptoms and maintaining a high quality of life among teenagers.

Functional α7 nicotinic receptors in human airway smooth muscle increase intracellular calcium concentration and contractility in asthmatics

Although nicotinic acetylcholine receptors (nAChRs) are commonly associated with neurons in the brain and periphery, recent data indicate that they are also expressed in non-neuronal tissues. We recently found the alpha7 (α7nAChR) subunit is highly expressed in human airway smooth muscle (hASM) with substantial increase in asthmatics, but their functionality remains unknown. We investigated the location and functional role of α7nAChRs in hASM cells from normal versus mild-moderate asthmatic patients. Immunostaining and protein analyses showed α7nAChR in the plasma membrane including in asthmatics. In asthmatic hASM, patch-clamp recordings revealed significantly higher functional homomeric α7nAChR channels. Real-time fluorescence imaging showed nicotine, via α7nAChR, increases intracellular Ca2+ ([Ca2+]i) independent of ACh effects, particularly in asthmatic hASM, while cellular traction force microscopy showed nicotine-induced contractility including in asthmatics. These results indicate functional homomeric and heteromeric nAChRs that are increased in asthmatic hASM, with pharmacology that likely differ owing to different subunit interfaces that form the orthosteric sites. nAChRs may represent a novel target in alleviating airway hyperresponsiveness in asthma.NEW & NOTEWORTHY Cigarette smoking and vaping exacerbate asthma. Understanding the mechanisms of nicotine effects in asthmatic airways is important. This study demonstrates that functional alpha7 nicotinic acetylcholine receptors (α7nAChRs) are expressed in human airway smooth muscle, including from asthmatics, and enhance intracellular calcium and contractility. Although a7nAChRs are associated with neuronal pathways, α7nAChR in smooth muscle suggests inhaled nicotine (e.g., vaping) can directly influence airway contractility. Targeting α7nAChR may represent a novel approach to alleviating airway hyperresponsiveness in asthma.

Tests for confounding with cigarette smoking in the association of E-cigarette use with respiratory disorder: 2020 National-Sample Data

Associations of e-cigarette use with respiratory disorder have been demonstrated but it has been unclear whether these are confounded by current or previous cigarette smoking. We address this question through studying different time frames for e-cigarette use and respiratory disorders in 2020 BRFSS data (N = 214,945). E-cigarette use and combustible cigarette smoking were classified into four categories: Participant never used either (Nonuse); used e-cigarettes/cigarettes but not in the past 30 days (Former Use), used in past 30 days on some days (Nondaily Use), or used past 30 days on all days (Daily Use). Contrasts for e-cigarette status and cigarette status (with nonuse as reference group) were entered with covariates in logistic regression with asthma or COPD as criterion. Stratified analyses of e-cigarette use were also performed for smokers and nonsmokers. In the total sample, results showed independent positive associations with both lifetime and current asthma for Former, Nondaily, and Daily e-cigarette use (mostly p < .0001) and the three cigarette indices. Significant positive associations with COPD were found for the three e-cigarette indices (p < .0001) and all the cigarette indices. Stratified analyses showed significant associations of e-cigarette use with respiratory disorder among nonsmokers as well as among smokers. We conclude that independent associations for former e-cigarette use (controlling for current/former smoking) and significant associations of e-cigarette use with respiratory disorder among nonsmokers indicate these associations are not confounded with cigarette smoking and suggest reverse causation is implausible. Findings for former use are discussed with reference to possible mechanisms including sensitization effects.