The Role of Nicotine in the Effects of Maternal Smoking during Pregnancy on Lung Development and Childhood Respiratory Disease. Implications for Dangers of E-Cigarettes

Perinatal nicotine vaping exposure induces pro-myofibroblastic phenotype in rat bone marrow-derived mesenchymal stem cells

Perinatal nicotine exposure via tobacco smoking results in increased proclivity to chronic lung disease (CLD); however, the underlying molecular mechanisms remain incompletely understood. We previously demonstrated that in addition to nicotine's direct effects on the developing lung, there are also adverse molecular alterations in bone marrow-derived mesenchymal stem cells (BMSCs), which are vital to lung injury repair. Whether perinatal nicotine exposure via electronic-cigarette (e-cig) vaping also adversely affects BMSCs is unknown. This is highly relevant due to marked increase in e-cig vaping including by pregnant women. Hypothesizing that perinatal nicotine exposure via e-cig vaping predisposes BMSCs to a pro-myofibroblastic phenotype, pregnant rat dams were exposed to fresh air (control), vehicle (e-cig without nicotine), or e-cig (e-cig with nicotine) daily during pregnancy and lactation. At postnatal day 21, offspring BMSCs were isolated and studied for cell proliferation, migration, wound healing response, and expression of key Wnt and PPARγ signaling intermediates (β-catenin, LEF-1, PPARγ, ADRP and C/EBPα) and myogenic markers (fibronectin, αSMA, calponin) proteins using immunoblotting. Compared to controls, perinatal e-cig exposure resulted in significant decrease in BMSC proliferation, migration, and wound healing response. The expression of key Wnt signaling intermediates (β-catenin, LEF-1) and myogenic markers (fibronectin, αSMA, calponin) increased significantly, while PPARγ signaling intermediates (PPARγ, ADRP, and C/EBPα) decreased significantly. Based on these data, we conclude that perinatally e-cig exposed BMSCs demonstrate pro-myofibroblastic phenotype and impaired injury-repair potential, indicating a potentially similar susceptibility to CLD following perinatal nicotine exposure via vaping as seen following parenteral perinatal nicotine exposure.

Epigenetic upregulation of carotid body angiotensin signaling increases blood pressure

Epigenetic changes can be shaped by a wide array of environmental cues as well as maternal health and behaviors. One of the most detrimental behaviors to the developing fetus is nicotine exposure. Perinatal nicotine exposure remains a significant risk factor for cardiovascular health and in particular, hypertension. Increased basal carotid body activity and excitation are significant contributors to hypertension. This study investigated the epigenetic changes to carotid body activity induced by perinatal nicotine exposure resulting in carotid body-mediated hypertension. Using a rodent model of perinatal nicotine exposure, we show that angiotensin II type 1 receptor is upregulated in the carotid bodies of nicotine-exposed offspring. These changes were attributed to an upregulation of genetic promotion as DNA methylation of angiotensin II type 1 receptor occurred within intron regions, exemplifying an upregulation of genetic transcription for these genes. Nicotine increased angiotensin signaling in vitro . Carotid body reactivity to angiotensin was increased in perinatal nicotine-exposed offspring compared to control offspring. Further, carotid body denervation reduced arterial pressure as a result of suppressed efferent sympathetic activity in perinatal nicotine-exposed offspring. Our data demonstrate that perinatal nicotine exposure adversely affects carotid body afferent sensing, which augments efferent sympathetic activity to increase vasoconstrictor signaling and induce hypertension. Targeting angiotensin signaling in the carotid bodies may provide a way to alleviate hypertension acquired by adverse maternal uterine environments in general and perinatal nicotine exposure in particular.

Maternal use of snus as smokeless tobacco in pregnancy and infant lung function

Background

Smoking in pregnancy has detrimental effects on infant respiratory health, while the effects of other nicotine-containing products on infant lung function are unclear. We aimed to explore if smokeless tobacco such as snus used in pregnancy increased the risk of lower lung function in infancy and if the associations differed by sex.

Methods

From the Scandinavian population-based Preventing Atopic Dermatitis and ALLergies in Children birth cohort, we included 1163 infants with available tidal flow-volume measurements at 3 months of age and maternal self-reported use of nicotine-containing products in pregnancy. The risk of a ratio of time to peak tidal expiratory flow to total expiratory time <25th percentile by any nicotine exposure, snus exclusively and cigarette smoking with or without other nicotine-containing products was explored by regression analyses adjusting for maternal age, education and asthma.

Results

Overall 120 out of 1163 (10.3%) infants were exposed to any nicotine in utero, 71 out of 120 by snus exclusively and 49 out of 120 by smoking, with six also exposed to snus. By pregnancy week 6, 85.8% of mothers reported stopping nicotine use. The risk of lower lung function was higher in children exposed in utero to nicotine-containing products with an odds ratio (OR) of 1.63 (95% confidence interval (CI) 1.02-2.59) with a similar tendency for snus exclusively (OR 1.55, 95% CI 0.88-2.71) and smoking (OR 1.79, 0.84-3.84). Effect estimates were similar after adjusting for covariates. No differences of the effect by sex were observed.

Conclusion

Our study suggests that in utero exposure to not only cigarettes, but also snus, may negatively affect infant lung function.

Use of cigarettes and heated tobacco products during pregnancy and maternal-fetal outcomes: a retrospective, monocentric study

PURPOSE

To compare the effects of using heated tobacco products (HTP) or traditional cigarettes (C) on maternal and neonatal outcomes.

METHODS

This is a retrospective, monocentric study conducted at San Marco Hospital from July 2021 to July 2022. We compared a cohort of pregnant patients who smoked HTP (HS), with pregnant women smoking cigarettes (CS), ex-smoker (ES) and non-smoker (NS) pregnant women. Biochemistry, ultrasound, and neonatal evaluations were performed.

RESULTS

In total, 642 women were enrolled, of which 270 were NS, 114 were ES, 120 were CS, and 138 were HS. CS had the greatest weight gain and had more difficulty getting pregnant. Smokers and ES experienced more frequently threats of preterm labor, miscarriages, temporary hypertensive spikes, and higher rates of cesarean sections. Preterm delivery was more associated with CS and HS groups. CS and HS had lower awareness of the risks to which the mother and the fetus are exposed. CS were more likely to be depressed and anxious. Biochemical parameters did not show significant differences between the groups. CS had the greatest difference in days between the gestational age calculated based on the last menstrual period and the one based on the actual ultrasound age. The average percentile newborn weight range of CS was lower, as well as the mean 1st minute and the 5th minute Apgar scores.

CONCLUSION

The comparison of the data obtained between CS and HS underlines the greater danger of C. Nevertheless, we do not recommend HTP because the maternal-fetal outcomes are not superimposable to the NS outcomes.

Nicotine or marijuana vaping exposure during pregnancy and altered immune responses in offspring

Electronic nicotine delivery systems (ENDS) - which include electronic cigarettes or e-cigarettes, or simply e-cigs, and marijuana vaping have become increasingly popular. ENDS devices have been established as one of the tobacco quit methods and promoted to be safer compared to traditional tobacco cigarettes. Emerging evidence demonstrates that e-cigarette and marijuana vape use can be harmful, with potential associations with cancer. Herein, we summarize the level of evidence to date for altered immune response, with a focus on cancer risks in the offspring after maternal use of, or aerosol exposures from, ENDS or marijuana vape during pregnancy. From 27 published articles retrieved from PubMed, we sought to find out identified carcinogens in ENDS aerosols and marijuana vapor, which cross the placental barrier and can increase cancer risk in the offspring. Carcinogens in vaping aerosols include aldehydes, metals, tobacco-specific nitrosamines, tobacco alkaloids, polycyclic aromatic hydrocarbons, and volatile organic compounds. Additionally, there was only one passive vaping exposure case study on a human fetus, which noted that glycerol, aluminum, chromium, nickel, copper, zinc, selenium, and lead crossed from the mother to the offspring's cord blood. The carcinogens (metals) in that study were at lower concentrations compared to the mother's biological matrices. Lastly, we observed that in utero exposures to ENDS-associated chemicals can occur in vital organs such as the lungs, kidneys, brain, bladder, and heart. Any resulting DNA damage increases the risk of tumorigenesis. Future epidemiological studies are needed to examine the effects of passive aerosol exposures from existing and emerging electronic nicotine and marijuana products on developing offspring to cancer.

Association of Fetal Lung Development Disorders with Adult Diseases: A Comprehensive Review

Fetal lung development is a crucial and complex process that lays the groundwork for postnatal respiratory health. However, disruptions in this delicate developmental journey can lead to fetal lung development disorders, impacting neonatal outcomes and potentially influencing health outcomes well into adulthood. Recent research has shed light on the intriguing association between fetal lung development disorders and the development of adult diseases. Understanding these links can provide valuable insights into the developmental origins of health and disease, paving the way for targeted preventive measures and clinical interventions. This review article aims to comprehensively explore the association of fetal lung development disorders with adult diseases. We delve into the stages of fetal lung development, examining key factors influencing fetal lung maturation. Subsequently, we investigate specific fetal lung development disorders, such as respiratory distress syndrome (RDS), bronchopulmonary dysplasia (BPD), congenital diaphragmatic hernia (CDH), and other abnormalities. Furthermore, we explore the potential mechanisms underlying these associations, considering the role of epigenetic modifications, transgenerational effects, and intrauterine environmental factors. Additionally, we examine the epidemiological evidence and clinical findings linking fetal lung development disorders to adult respiratory diseases, including asthma, chronic obstructive pulmonary disease (COPD), and other respiratory ailments. This review provides valuable insights for healthcare professionals and researchers, guiding future investigations and shaping strategies for preventive interventions and long-term care.

Why and how should children be protected from the deluge of vaping related media and marketing overexposure?

E-cigarettes are products delivering nicotine via inhalation and are devised to mimic tobacco smoking. While they were initially introduced as a device putatively to aid with smoking cessation, their use is now far broader than that. Use by children is significantly increasing. There is growing evidence of the potential harms of vaping. E-liquids used for e-cigarettes contain a wide range of harmful substances, and the clinical consequences of this are now being increasingly demonstrated, such as the rise in cases of e-cigarette- or vaping-associated lung injury. In addition, early use may result in long-term nicotine addiction. Vaping companies utilise marketing methods that distinctly target young people, and weak legislation in the UK allows them free rein to expose children to vaping. In this review we demonstrate why children must be protected from vaping. We must have stringent legislation to prevent easy access to e-cigarettes, including banning the convenience and affordability disposable vapes provide, and prevent marketing that does not warn about the potential health effects. The Australia approach of prescription or pharmacy only access for smoking cessation should be considered to limit exposure of children and minimise use by nonsmokers.

An Evaluation of the Impact of Air Pollution on the Lung Functions of High School Students Living in a Ceramic Industrial Park Zone

Santa Gertrudes (SG) and Rio Claro (RC), Sao Paulo, Brazil, are located in a ceramic industrial park zone, and their particulate matter with an aerodynamic diameter of less than 10 µm (PM10) concentration levels has been among the highest in recently monitored cities in Brazil. Local PM10 was mostly composed of silica. A cross-sectional study was designed to evaluate the lung functions of public high school students in SG, RC, and São Pedro (SP) (control location), Brazil, in 2018. The prevalence of asthma, mean PM10, FVC (forced vital capacity), and FEV1 (forced expiratory volume in the first second) were compared between the locations, and regression analyses were performed. A total of 450 students were included (SG: 158, RC: 153, and SP: 139). The mean FVC% (SG: 95.0% ± 11.8%, RC: 98.8% ± 12.9%, SP: 102.4% ± 13.8%, p < 0.05), the mean FEV1% (SG: 95.7% ± 10.4%, RC: 99.7% ± 12.0%, SP: 103.2% ± 12.0%, p < 0.05) and the mean PM10 (SG: 77.75 ± 38.08 µg/m3, RC: 42.59 ± 23.46 µg/m3, SP: 29.52 ± 9.87 µg/m3, p < 0.01) differed between locations. In regression models, each increase in PM10 by 10 µg/m3 was associated with a decrease in FVC% by 1.10% (95% CI 0.55%-1.65%) and a decrease in FEV1% by 1.27% (95% CI 0.75%-1.79%). Exposure to high levels of silica-rich environmental PM10 was found to be associated with lower FVC and FEV1.

Nicotine Use During Pregnancy: Cessation and Treatment Strategies

Abstract

The use of tobacco and nicotine products during pregnancy is known to increase the risk of adverse effects on the fetus. Increased education and research have resulted in greater rates of smoking cessation during pregnancy, with a decline from 13.2% of pregnant individuals smoking in 2006 to 7.2% in 2016. However, smoking while pregnant still proves to be a prevalent issue that is associated with numerous adverse outcomes, including low birth weight, preterm birth, and developmental delays. Smoking cessation before or during pregnancy can help mitigate these effects, but the appropriate treatment can be challenging to ascertain. Accordingly, clinicians should look to provide individualized care composed of behavioral counseling in conjunction with pharmacotherapies when indicated, combined with ongoing support and education.

Prenatal nicotine exposure during pregnancy results in adverse neurodevelopmental alterations and neurobehavioral deficits

Maternal tobacco use and nicotine exposure during pregnancy have been associated with adverse birth outcomes in infants and can lead to preventable pregnancy complications. Exposure to nicotine and other compounds in tobacco and electronic cigarettes (e-cigarettes) has been shown to increases the risk of miscarriage, prematurity, stillbirth, low birth weight, perinatal morbidity, and sudden infant death syndrome (SIDS). Additionally, recent data provided by clinical and pre-clinical research demonstrates that nicotine exposure during pregnancy may heighten the risk for adverse neurodevelopmental disorders such as Attention-Deficit Hyperactivity (ADHD), anxiety, and depression along with altering the infants underlying brain circuitry, response to neurotransmitters, and brain volume. In the United States, one in 14 women (7.2%) reported to have smoked cigarettes during their pregnancy with the global prevalence of smoking during pregnancy estimated to be 1.7%. Approximately 1.1% of women in the United States also reported to have used e-cigarettes during the last 3 months of pregnancy. Due to the large percentage of women utilizing nicotine products during pregnancy in the United States and globally, this review seeks to centralize pre-clinical and clinical studies focused on the neurobehavioral and neurodevelopmental complications associated with prenatal nicotine exposure (PNE) such as alterations to the hypothalamic-pituitary-adrenal (HPA) axis and brain regions such as the prefrontal cortex (PFC), ventral tegmental area (VTA), nucleus accumbens (NA), hippocampus, and caudate as well as changes to nAChR and cholinergic receptor signaling, long-term drug seeking behavior following PNE, and other related developmental disorders. Current literature analyzing the association between PNE and the risk for offspring developing schizophrenia, attention-deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD), anxiety, and obesity will also be discussed.

Preterm Birth, Developmental Smoke/Nicotine Exposure, and Life-Long Pulmonary Sequelae

This review delineates the main pulmonary issues related to preterm birth, perinatal tobacco/nicotine exposure, and its effects on offspring, focusing on respiratory health and its possible transmission to subsequent generations. We review the extent of the problem of preterm birth, prematurity-related pulmonary effects, and the associated increased risk of asthma later in life. We then review the impact of developmental tobacco/nicotine exposure on offspring asthma and the significance of transgenerational pulmonary effects following perinatal tobacco/nicotine exposure, possibly via its effects on germline epigenetics.

Comparative study of e-cigarette aerosol and cigarette smoke effect on ex vivo embryonic chick lung explants

Electronic cigarette usage has significantly expanded among young people and pregnant women in the last decade. Although there are already some data regarding the short- and long-term consequences of e-cigarettes on human health, their effect on embryo and lung development still needs to be fully disclosed. In this sense, this study describes, for the first time, the impact of electronic cigarette aerosol on early lung development. For this purpose, ex vivo chick (Gallus gallus) embryonic lungs were cultured in vitro for 48 h in e-cigarette aerosol exposed-medium or unexposed medium. Chick lung explants were also cultured in a cigarette smoke-exposed medium for comparison purposes. Lung explants were morphologically analyzed to assess the impact on lung growth. Additionally, TNF-α levels were determined in the supernatant as a marker of pro-inflammatory response. The results suggest that electronic cigarette aerosol impairs lung growth and promotes lung inflammation. However, its impact on early lung growth seems less detrimental than conventional cigarette smoke. This work provides significant data regarding the impact of e-cig aerosol, adding to the efforts to fully understand its effect on embryo development. The validation of these effects may eventually lead to new tobacco control recommendations for pregnant women.

The Role of Lung Function in Determining Which Children Develop Asthma

Longitudinal studies have demonstrated that altered indices of airway function, assessed shortly after birth, are a risk factor for the subsequent development of wheezing illnesses and asthma, and that these indices predict airway size and airway wall thickness in adult life. Pre- and postnatal factors that directly alter early airway function, such as extreme prematurity and cigarette smoke, may continue to affect airway function and, hence, the risks for wheeze and asthma. Early airway function and an associated asthma risk may also be indirectly influenced by immune system responses, respiratory viruses, the airway microbiome, genetics, and epigenetics, especially if they affect airway epithelial dysfunction. Few if any interventions, apart from smoking avoidance, have been proven to alter the risks of developing asthma, but vitamin C supplementation to pregnant smokers may help decrease the effects of in utero smoke on offspring lung function. We conclude that airway size and the factors influencing this play an important role in determining the risk for asthma across the lifetime. Progress in asthma prevention is long overdue and this may benefit from carefully designed interventions in well-phenotyped longitudinal birth cohorts with early airway function assessments monitored through to adulthood.

Adverse Maternal and Infant Outcomes of Women Who Differ in Smoking Status: E-Cigarette and Tobacco Cigarette Users

The electronic cigarette (e-cigarette) became commercially available around 2004, yet the characteristics of pregnant women who use these devices and their effects on maternal and infant health remain largely unknown. This study aimed to investigate maternal characteristics and pregnancy outcomes according to maternal smoking status. We conducted a cross-sectional study of Dutch women with reported pregnancies between February 2019 and May 2022, using an online questionnaire to collect data on smoking status and demographic, lifestyle, pregnancy, and infant characteristics. Smoking status is compared among non-smokers, tobacco cigarette users, e-cigarette users, and dual users (tobacco and e-cigarette). We report descriptive statistics and calculate differences in smoking status between women with the chi-square or Fisher (Freeman-Halton) test. Of the 1937 included women, 88.1% were non-smokers, 10.8% were tobacco cigarette users, 0.5% were e-cigarette users, and 0.6% were dual users. Compared with tobacco users, e-cigarette users more often reported higher education, having a partner, primiparity, and miscarriages. Notably, women who used e-cigarettes more often had small infants for gestational age. Despite including few women in the e-cigarette subgroup, these exploratory results indicate the need for more research to examine the impact of e-cigarettes on pregnancy outcomes.

The causal association between maternal smoking around birth on childhood asthma: A Mendelian randomization study

To explore the causal relationship between maternal smoking around birth and childhood asthma using Mendelian randomization (MR). Using the data from large-scale genome-wide association studies, we selected independent genetic loci closely related to maternal smoking around birth and maternal diseases as instrumental variables and used MR methods. In this study, we considered the inverse variance weighted method (MR-IVW), weighted median method, and MR-Egger regression. We investigated the causal relationship between maternal smoking around birth and maternal diseases in childhood asthma using the odds ratio (OR) as an evaluation index. Multivariable MR (MVMR) included maternal history of Alzheimer's disease, illnesses of the mother: high blood pressure and illnesses of the mother: heart diseaseas covariates to address potential confounding. Sensitivity analyses were evaluated for weak instrument bias and pleiotropic effects. It was shown with the MR-IVW results that maternal smoking around birth increased the risk of childhood asthma by 1.5% (OR = 1.0150, 95% CI: 1.0018-1.0283). After the multivariable MR method was used to correct for relevant covariates, the association effect between maternal smoking around birth and childhood asthma was still statistically significant (P < 0.05). Maternal smoking around birth increases the risk of childhood asthma.

Nicotine Exposure during Rodent Pregnancy Alters the Composition of Maternal Gut Microbiota and Abundance of Maternal and Amniotic Short Chain Fatty Acids

Tobacco smoking is the leading cause of preventable death. Numerous reports link smoking in pregnancy with serious adverse outcomes, such as miscarriage, stillbirth, prematurity, low birth weight, perinatal morbidity, and infant mortality. Corollaries of consuming nicotine in pregnancy, separate from smoking, are less explored, and the mechanisms of nicotine action on maternal–fetal communication are poorly understood. This study examined alterations in the maternal gut microbiome in response to nicotine exposure during pregnancy. We report that changes in the maternal gut microbiota milieu are an important intermediary that may mediate the prenatal nicotine exposure effects, affect gene expression, and alter fetal exposure to circulating short-chain fatty acids (SCFAs) and leptin during in utero development.

Tobacco use during pregnancy

The use of tobacco during pregnancy is the leading preventable cause of pregnancy complications and adverse birth outcomes. In high-income countries, around one in 10 pregnant women smokes tobacco, while smokeless tobacco is the primary form of tobacco used in many low- and middle-income countries. Although the risk of tobacco-related harms can be reduced substantially if mothers cease smoking in the first trimester of pregnancy, the proportion of women who successfully quit smoking during pregnancy remains modest. Psychosocial interventions are first-line treatment, with some high-quality evidence showing that counselling is effective in promoting smoking cessation among pregnant women. There is insufficient evidence regarding the efficacy and safety of smoking cessation pharmacotherapies when used during pregnancy, although in some countries nicotine replacement therapy is recommended for pregnant women who have been unable to quit without pharmacological assistance. E-cigarettes are increasingly being used as a smoking cessation aid in the general population of smokers, but more research is needed to determine if e-cigarettes are a safe and effective treatment option for pregnant women.

Alterations of Mitochondrial Network by Cigarette Smoking and E-Cigarette Vaping

Toxins present in cigarette and e-cigarette smoke constitute a significant cause of illnesses and are known to have fatal health impacts. Specific mechanisms by which toxins present in smoke impair cell repair are still being researched and are of prime interest for developing more effective treatments. Current literature suggests toxins present in cigarette smoke and aerosolized e-vapor trigger abnormal intercellular responses, damage mitochondrial function, and consequently disrupt the homeostasis of the organelle's biochemical processes by increasing reactive oxidative species. Increased oxidative stress sets off a cascade of molecular events, disrupting optimal mitochondrial morphology and homeostasis. Furthermore, smoking-induced oxidative stress may also amalgamate with other health factors to contribute to various pathophysiological processes. An increasing number of studies show that toxins may affect mitochondria even through exposure to secondhand or thirdhand smoke. This review assesses the impact of toxins present in tobacco smoke and e-vapor on mitochondrial health, networking, and critical structural processes, including mitochondria fission, fusion, hyper-fusion, fragmentation, and mitophagy. The efforts are focused on discussing current evidence linking toxins present in first, second, and thirdhand smoke to mitochondrial dysfunction.

Patterns and Trends in Use of Electronic Nicotine Delivery Systems Before and During Pregnancy: Pregnancy Risk Assessment Monitoring System, United States, 2016-2019

INTRODUCTION

This study used 2016-2019 Pregnancy Risk Assessment Monitoring System data to estimate prevalence of electronic nicotine delivery system (ENDS) use around pregnancy, changes in ENDS use and cigarette smoking from before to during pregnancy, and trends in these behaviors over time.

METHODS

ENDS and cigarette use during the 3 months before and the last three months of pregnancy were measured. Weighted prevalence estimates and 95% confidence intervals were estimated for outcomes overall and ENDS use by maternal characteristic for 2016-2019; logistic regression tested for differences in ENDS use by maternal characteristic and for linear trends in ENDS and cigarette use before and during pregnancy. Analyses were completed in 2021.

RESULTS

In 2019, 4.3% (N = 98,050) of women used ENDS before and 1.3% (N = 28,811) used ENDS during pregnancy. Most exclusive ENDS users (82.2%) and exclusive cigarette smokers (55.0%) stopped use during pregnancy. Among dual users, 46.3% stopped use during pregnancy while 20.2% continued dual use and 24.9% smoked cigarettes exclusively. Few dual users (8.6%) and exclusive cigarette smokers (0.5%) reported using ENDS exclusively during pregnancy. From 2016-2019, exclusive ENDS use increased and exclusive cigarette smoking decreased both before and during pregnancy.

CONCLUSIONS

ENDS use during pregnancy is low but increased since 2016. Less than one-half of dual ENDS and cigarettes users quit during pregnancy; few dual users or exclusive cigarette smokers switched to exclusive ENDS use during pregnancy. Continued surveillance of ENDS and other tobacco use during pregnancy is critical to inform public health activities that protect maternal and child health.

In utero exposure to electronic-cigarette aerosols decreases lung fibrillar collagen content, increases Newtonian resistance and induces sex-specific molecular signatures in neonatal mice

Approximately 7% of pregnant women in the United States use electronic-cigarette (e-cig) devices during pregnancy. There is, however, no scientific evidence to support e-cig use as being 'safe' during pregnancy. Little is known about the effects of fetal exposures to e-cig aerosols on lung alveologenesis. In the present study, we tested the hypothesis that in utero exposure to e-cig aerosol impairs lung alveologenesis and pulmonary function in neonates. Pregnant BALB/c mice were exposed 2 h a day for 20 consecutive days during gestation to either filtered air or cinnamon-flavored e-cig aerosol (36 mg/mL of nicotine). Lung tissue was collected in offspring during lung alveologenesis on postnatal day (PND) 5 and PND11. Lung function was measured at PND11. Exposure to e-cig aerosol in utero led to a significant decrease in body weights at birth which was sustained through PND5. At PND5, in utero e-cig exposures dysregulated genes related to Wnt signaling and epigenetic modifications in both females (~ 120 genes) and males (40 genes). These alterations were accompanied by reduced lung fibrillar collagen content at PND5-a time point when collagen content is close to its peak to support alveoli formation. In utero exposure to e-cig aerosol also increased the Newtonian resistance of offspring at PND11, suggesting a narrowing of the conducting airways. At PND11, in females, transcriptomic dysregulation associated with epigenetic alterations was sustained (17 genes), while WNT signaling dysregulation was largely resolved (10 genes). In males, at PND11, the expression of only 4 genes associated with epigenetics was dysregulated, while 16 Wnt related-genes were altered. These data demonstrate that in utero exposures to cinnamon-flavored e-cig aerosols alter lung structure and function and induce sex-specific molecular signatures during lung alveologenesis in neonatal mice. This may reflect epigenetic programming affecting lung disease development later in life.

Harmful Effect of Intrauterine Smoke Exposure on Neuronal Control of "Fetal Breathing System" in Stillbirths

This article is aimed to contribute to the current knowledge on the role of toxic substances such as nicotine on sudden intrauterine unexplained deaths’ (SIUDS’) pathogenetic mechanisms. The in-depth histopathological examination of the autonomic nervous system in wide groups of victims of SIUDS (47 cases) and controls (20 cases), with both smoking and no-smoking mothers, highlighted the frequent presence of the hypodevelopment of brainstem structures checking the vital functions. In particular, the hypoplasia of the pontine parafacial nucleus together with hypoplastic lungs for gestational age were observed in SIUDS cases with mothers who smoked cigarettes, including electronic ones. The results allow us to assume that the products of cigarette smoke during pregnancy can easily cross the placental barrier, thus entering the fetal circulation and damaging the most sensitive organs, such as lungs and brain. In a non-negligible percentage of SIUDS, the mothers did not smoke. Furthermore, based on previous and ongoing studies conducted through analytical procedures and the use of scanning electron microscopy, the authors envisage the involvement of toxic nanoparticles (such as agricultural pesticides and nanomaterials increasingly used in biomedicine, bioscience and biotechnology) in the death pathogenesis, with similar mechanisms to those of nicotine.

Adverse early-life environmental exposures and their repercussions on adult respiratory health

OBJECTIVE

To review in the literature the environmental problems in early life that impact the respiratory health of adults.

SOURCES

Non-systematic review including articles in English. Search filters were not used in relation to the publication date, but the authors selected mainly publications from the last five years.

SUMMARY OF THE FINDINGS

In this review, the authors present the exposure pathways and how the damage occurs depending on the child's stage of development; the authors describe the main environmental pollutants - tobacco smoke, particulate matter, air pollution associated with traffic, adverse childhood experiences and socioeconomic status; the authors present studies that evaluated the repercussions on the respiratory system of adults resulting from exposure to adverse environmental factors in childhood, such as increased incidence of Chronic Obstructive Pulmonary Disease (COPD), asthma and allergies; and, a decline in lung function. The authors emphasize that evidence demonstrates that adult respiratory diseases almost always have their origins in early life. Finally, the authors emphasize that health professionals must know, diagnose, monitor, and prevent toxic exposure among children and women.

CONCLUSION

The authors conclude that it is necessary to recognize risk factors and intervene in the period of greatest vulnerability to the occurrence of harmful effects of environmental exposures, to prevent, delay the onset or modify the progression of lung disease throughout life and into adulthood.

A group-sequential randomized trial design utilizing supplemental trial data

Definitive clinical trials are resource intensive, often requiring a large number of participants over several years. One approach to improve the efficiency of clinical trials is to incorporate historical information into the primary trial analysis. This approach has tremendous potential in the areas of pediatric or rare disease trials, where achieving reasonable power is difficult. In this article, we introduce a novel Bayesian group-sequential trial design based on Multisource Exchangeability Models, which allows for dynamic borrowing of historical information at the interim analyses. Our approach achieves synergy between group sequential and adaptive borrowing methodology to attain improved power and reduced sample size. We explore the frequentist operating characteristics of our design through simulation and compare our method to a traditional group-sequential design. Our method achieves earlier stopping of the primary study while increasing power under the alternative hypothesis but has a potential for type I error inflation under some null scenarios. We discuss the issues of decision boundary determination, power and sample size calculations, and the issue of information accrual. We present our method for a continuous and binary outcome, as well as in a linear regression setting.

Nicotine replacement therapy and e-cigarettes in pregnancy and infant respiratory outcomes

BACKGROUND

Nicotine replacement therapy (NRT) and e-cigarettes are recommended to pregnant women who wish to stop smoking. Albeit eliminating other harmful components of cigarettes, those alternatives still expose the developing fetus to nicotine. The lungs may be particularly vulnerable to damage by nicotine as there is widespread nicotinic-acetylcholine receptor expression in the lungs. There is, however, a paucity of information about the effect of NRT and e-cigarette use in pregnancy on infant respiratory outcomes.

AIMS

To explore the effect of NRT and e-cigarettes on the developing lung.

STUDY DESIGN

A literature search was undertaken to examine the use and safety of nicotine-replacement strategies in pregnancy, with a focus on infant respiratory outcomes. This included experimental studies investigating the effect of isolated "gestational" nicotine on the developing lung.

OUTCOME MEASURES

Respiratory outcomes in animal studies and infants.

RESULTS

Animal studies investigating the effect of gestational nicotine exposure on fetal lung development demonstrated abnormal lung growth; including abnormal airway branching and alveolar development. Consequently, offspring display altered pulmonary mechanics, including both increased respiratory rate and airway resistance. These findings mirror respiratory pathology observed in infants born to smoking mothers. Human trials of NRT and e-cigarette use in pregnancy have not identified adverse perinatal outcomes regarding reduced birthweight or prematurity, but have not considered infant and childhood respiratory outcomes.

CONCLUSIONS

Nicotine can impair fetal lung development, leading to concerns regarding the safety of NRT and e-cigarettes in pregnancy. Studies have yet to explore the impact of these nicotine-containing products on infant respiratory outcomes.

Tobacco use disorder and the lungs

This narrative review provides a summary of the impact of tobacco smoking on the respiratory system and the benefits of smoking cessation. Tobacco smoking is one of the leading preventable causes of death world-wide and a major risk factor for lung cancer and chronic obstructive pulmonary disease. Smoking is also associated with an increased risk of respiratory infections and appears to be related to poorer outcomes among those with COVID-19. Non-smokers with second-hand smoke exposure also experience significant adverse respiratory effects. Smoking imposes enormous health- and non-health-related costs to societies. The benefits of smoking cessation, in both prevention and management of respiratory disease, have been known for decades and, to this day, cessation support remains one of the most important cost-effective interventions that health professionals can provide to people who smoke. Cessation at any age confers substantial health benefits, even in smokers with established morbidities. As other treatments for chronic respiratory disease advance and survival rates increase, smoking cessation treatment will become even more relevant. While smoking cessation interventions are available, the offer of these by clinicians and uptake by patients remain limited.

Electronic Nicotine Delivery Systems (ENDS) Use and Pregnancy II: Perinatal Outcomes Following ENDS Use During Pregnancy

Purpose of Review

This review examines the risk of adverse perinatal outcomes following electronic nicotine delivery system (ENDS) use during pregnancy, and considers whether there are sufficient data to support ENDS as a harm reduction approach during pregnancy.

Recent Findings

Seven papers assessed perinatal outcomes following ENDS use during pregnancy. There was evidence that ENDS use was associated with increased risk for some adverse perinatal outcomes (e.g., small for gestational age). However, the repeated use of data sets, insufficient data (e.g., timing of ENDS use, type of ENDS products used), and limited samples size, contributed to mixed findings on the degree to which ENDS use (alone or in combination with combustible cigarettes (CC)) impacts the risk of adverse perinatal outcomes relative to CC smoking alone.

Summary

The current data are still insufficient to support ENDS as a harm reduction approach, though findings do warrant concern and more detailed investigation of ENDS use during pregnancy. Future research directions, as well as implications for clinical recommendations and tobacco regulatory science are discussed.

The First 1000 Days: Impact of Prenatal Tobacco Smoke Exposure on Hospitalization Due to Preschool Wheezing

Preschool wheezing and related hospitalization rates are increasing. Prenatal tobacco smoke exposure (PTSE) increases the risk of wheezing, yet >20% of French women smoke during pregnancy. In this observational retrospective monocentric study, we assessed the link between PTSE and hospital admissions. We included infants <2 years of age admitted for acute wheezing. A phone interview with mothers was completed by electronic records. The primary endpoint was the ratio of cumulative duration of the hospitalization stays (days)/age (months). 129 children were included (36.4% exposed to PTSE vs. 63.6% unexposed). There was a significant difference in the duration of hospitalization/age: 0.9 days/month (exposed) vs. 0.58 days/month (unexposed) (p = 0.008). Smoking one cigarette/day during pregnancy was associated with an increase in hospitalization duration of 0.055 days/month (r = 0.238, p = 0.006). In the multi-variable analysis, this positive association persisted (β = 0.04, p = 0.04; standardized β = 0.27, p = 0.03). There was a trend towards a dose-effect relationship between PTSE and other important parameters associated with hospital admissions. We have demonstrated a dose-effect relationship, without a threshold effect, between PTSE and duration of hospitalization for wheezing in non-premature infants during the first 2 years of life. Prevention campaigns for future mothers should be enforced.

Prevalence and Distribution of Electronic Cigarette Use Before and During Pregnancy Among Women in 38 States of the United States

INTRODUCTION

To examine the prevalence and the changing pattern of e-cigarette use from preconception to pregnancy.

AIMS AND METHODS

This is a cross-sectional study using data from the multi-site Pregnancy Risk Assessment Monitoring System in the United States, 2016-2017. All participating mothers with information on e-cigarette use before and during pregnancy were included. Self-reported information about e-cigarette use were assessed using questionnaires. Weighted prevalences of e-cigarette use before and during pregnancy were calculated. Multivariable logistic regressions were used to examine the association between various demographic characteristics and e-cigarette use before or during pregnancy.

RESULTS

This study included 69 508 pregnant women from 38 states in the United States. The weighted prevalence of e-cigarette use before pregnancy and during the last 3 months of pregnancy was 3.6% (95% confidence interval [CI] 3.4%-3.9%) and 1.1% (0.9%-1.2%), respectively. The prevalence varied across states, ranging from 1.3% to 8.3% for e-cigarette use before pregnancy and from 0.1% to 3.4% for e-cigarette use during the last 3 months of pregnancy. Among women who used e-cigarettes before pregnancy, 24.4% (21.7%-27.1%) continued to use e-cigarettes during pregnancy. Among women who used e-cigarettes during pregnancy, 62.3% (56.5%-68.0%) were dual users. In multivariable analyses, cigarette smoking was most strongly associated with e-cigarette use. The adjusted odds ratio comparing smokers with nonsmokers before pregnancy was 11.10 (95% CI 9.34-13.20) for e-cigarette use before pregnancy and 6.72 (95% CI 4.38-10.31) for e-cigarette use during pregnancy.

CONCLUSIONS

Using data from 38 states in the United States, we showed geographical variations in the prevalence of e-cigarette use before and during pregnancy. Among women who used e-cigarettes before pregnancy, a quarter of them continued to use e-cigarettes during pregnancy. Conventional cigarette use is a strong risk factor for e-cigarette use before and during pregnancy. The prevalence of e-cigarette use needs to be monitored continuously.

IMPLICATIONS

This study provides important information to understand the status and changing patterns of e-cigarette use in pregnant women in the United States. Among pregnant women in 38 states in the United States, 3.6% of them used e-cigarettes during the 3 months before pregnancy and 1.1% used them during the last 3 months of pregnancy. The prevalence varied across states. A quarter of women who used e-cigarettes before pregnancy continued to use e-cigarettes during pregnancy. Cigarette smoking is the strongest predictor of e-cigarette use. Future research about health effects of e-cigarette use during pregnancy is in urgent need.

Electronic Cigarettes and Asthma: What Do We Know So Far?

Electronic cigarettes (EC) are a novel product, marketed as an alternative to tobacco cigarette. Its effects on human health have not been investigated widely yet, especially in specific populations such as patients with asthma. With this review, we use the existing literature in order to answer four crucial questions concerning: (1) ECs' role in the pathogenesis of asthma; (2) ECs' effects on lung function and airway inflammation in patients with asthma; (3) ECs' effects on asthma clinical characteristics in asthmatics who use it regularly; and (4) ECs' effectiveness as a smoking cessation tool in these patients. Evidence suggests that many EC compounds might contribute to the pathogenesis of asthma. Lung function seems to deteriorate by the use of EC in this population, while airway inflammation alters, with the aggravation of T-helper-type-2 (Th2) inflammation being the most prominent but not the exclusive effect. EC also seems to worsen asthma symptoms and the rate and severity of exacerbations in asthmatics who are current vapers, whilst evidence suggests that its effectiveness as a smoking cessation tool might be limited. Asthmatic patients should avoid using EC.

Passively inhaled tobacco smoke - pregnancy and neonatal outcomes in correlation with placental histopathology

INTRODUCTION

We aimed to investigate the effect of maternal passive smoking (MPS) during pregnancy-on placental pathology and pregnancy outcomes.

METHODS

A prospective case-control study. We recruited low-risk laboring women at 37+0-41 + 0 weeks between 9/2019-7/2020. MPS was defined as exposure to in-house spouse tobacco smoking of >20 cigarettes/day in the absence of maternal active-smoking. In attempt to "purify" the effect of MPS on placental pathology-we excluded cases with preeclampsia, diabetes, suspected fetal growth restriction (FGR), preterm labor, and illicit drug use. Maternal characteristics, pregnancy outcomes, and placental pathology were compared between the MPS group and a control group matched for gestational age, maternal age, and delivery date. Placental lesions were classified according to the "Amsterdam" criteria. The study was powered to detect a 33% difference in placental malperfusion lesions. Multivariable regression was performed to identify independent associations with placental malperfusion lesions.

RESULTS

In labor, the MPS group (n = 115) had higher rates of meconium stained amniotic fluid (MSAF, p < 0.001) and non-reassuring fetal heart-rate (NRFHR,p = 0.006), compared to controls (n = 115). Neonates in the MPS group had higher rates of undiagnosed FGR (p = 0.01) and NICU admissions (p = 0.004). The MPS group had higher rates of placental-hypoplasia (p = 0.02) and fetal vascular malperfusion (FVM) lesions (p = 0.04). In regression analysis MPS was associated with FVM lesions independent of background confounders (aOR = 1.24 95% CI 1.10-2.65).

DISCUSSION

In otherwise low-risk pregnancies, MPS was associated with higher rates of MSAF, NRFHR, undiagnosed FGR, and NICU admissions, probably mediated via placental FVM. These worrisome findings mandate patient counseling and further investigation in larger population-based studies.

Perinatal exposure to nicotine alters spermatozoal DNA methylation near genes controlling nicotine action

Perinatal smoke/nicotine exposure alters lung development and causes asthma in exposed offspring, transmitted transgenerationally. The mechanism underlying the transgenerational inheritance of perinatal smoke/nicotine-induced asthma remains unknown, but germline epigenetic modulations may play a role. Using a well-established rat model of perinatal nicotine-induced asthma, we determined the DNA methylation pattern of spermatozoa of F1 rats exposed perinatally to nicotine in F0 gestation. To identify differentially methylated regions (DMRs), reduced representation bisulfite sequencing was performed on spermatozoa of F1 litters. The top regulated gene body and promoter DMRs were tested for lung gene expression levels, and key proteins involved in lung development and repair were determined. The overall CpG methylation in F1 sperms across gene bodies, promoters, 5'-UTRs, exons, introns, and 3'-UTRs was not affected by nicotine exposure. However, the methylation levels were different between the different genomic regions. Eighty one CpG sites, 16 gene bodies, and 3 promoter regions were differentially methylated. Gene enrichment analysis of DMRs revealed pathways involved in oxidative stress, nicotine response, alveolar and brain development, and cellular signaling. Among the DMRs, Dio1 and Nmu were the most hypermethylated and hypomethylated genes, respectively. Gene expression analysis showed that the mRNA expression and DNA methylation were incongruous. Key proteins involved in lung development and repair were significantly different (FDR < 0.05) between the nicotine and placebo-treated groups. Our data show that DNA methylation is remodeled in offspring spermatozoa upon perinatal nicotine exposure. These epigenetic alterations may play a role in transgenerational inheritance of perinatal smoke/nicotine induced asthma.

Effect of prenatal and postnatal exposure to tobacco in the development of acute bronchiolitis in the first two years of life

INTRODUCTION

Environmental exposure to tobacco increases the risk of respiratory disease in infants. However, the impact of maternal smoking on the development of acute bronchiolitis has hardly been assessed. The aim of this study was to determine the incidence of acute bronchiolitis and to analyse the effect of prenatal and postnatal maternal smoking on the development of this disease.

PATIENTS AND METHODS

A prospective, observational study was performed on healthy newborns from a third level hospital born between October 2015 and February 2016. Questionnaires were completed by the mothers at discharge from maternity and followed-up for two years. These collected information about prenatal and postnatal smoking, lifestyle, family and personal history, and the development of bronchiolitis. A bivariate and multivariate logistic regression analysis was performed.

RESULTS

A total of 223 newborns were included, of whom 13.9% were exposed to tobacco smoking during gestation, 21.4% in the postnatal period, and 12.4% in both times. The incidence of bronchiolitis was 28.7% at one year of life, and 34.5% at two years. The multivariate analysis demonstrated that the prenatal and postnatal exposure to tobacco is an independent risk factor for the development of bronchiolitis (OR 4.38; 95% CI; 1.63-11.76), while prolonged breastfeeding is a protective factor (OR 0.13; 95% CI; 0.04-0.48). Other factors that were statistically significant were: atopic dermatitis (OR 2.91; 95% CI; 1.26-6.73), and gestational age (OR 1.42; 95% CI; 1.08-1.88).

CONCLUSIONS

Children exposed to prenatal and postnatal maternal smoking have a higher risk of suffering bronchiolitis. Reducing the smoking habit in women that intend to become pregnant must be a priority in preventive medicine.

The Shared Genetic Architectures Between Lung Cancer and Multiple Polygenic Phenotypes in Genome-Wide Association Studies

BACKGROUND

Prior genome-wide association studies have identified numerous lung cancer risk loci and reveal substantial etiologic heterogeneity across histologic subtypes. Analyzing the shared genetic architecture underlying variation in complex traits can elucidate common genetic etiologies across phenotypes. Exploring pairwise genetic correlations between lung cancer and other polygenic traits can reveal the common genetic etiology of correlated phenotypes.

METHODS

Using cross-trait linkage disequilibrium score regression, we estimated the pairwise genetic correlation and heritability between lung cancer and multiple traits using publicly available summary statistics. Identified genetic relationships were also examined after excluding genomic regions known to be associated with smoking behaviors, a major risk factor for lung cancer.

RESULTS

We observed several traits showing moderate single nucleotide polymorphism-based heritability and significant genetic correlations with lung cancer. We observed highly significant correlations between the genetic architectures of lung cancer and emphysema/chronic bronchitis across all histologic subtypes, as well as among lung cancer occurring among smokers. Our analyses revealed highly significant positive correlations between lung cancer and paternal history of lung cancer. We also observed a strong negative correlation with parental longevity. We observed consistent directions in genetic patterns after excluding genomic regions associated with smoking behaviors.

CONCLUSIONS

This study identifies numerous phenotypic traits that share genomic architecture with lung carcinogenesis and are not fully accounted for by known smoking-associated genomic loci.

IMPACT

These findings provide new insights into the etiology of lung cancer by identifying traits that are genetically correlated with increased risk of lung cancer.

Childhood Origins of Adult Lung Disease as Opportunities for Prevention

Prenatal and childhood exposures have been shown to impact lung development, lung function trajectory, and incidence and prevalence of respiratory disease. Early life may serve as a window of susceptibility to such exposures, with the potential to influence lifelong respiratory health. Risk factors encountered in early life with potentially durable impact on lung health include prematurity, respiratory viral illness, allergen sensitization and exposure, tobacco use and exposure, indoor and outdoor pollution, diet, and obesity. These exposures vary in the extent to which they are modifiable, and interventions aimed at reducing harmful exposures range from individual-level behavior modification to policy initiatives implemented to promote population health. For many exposures, including tobacco-related exposures, multilevel interventions are needed. Future research is needed to provide insight as to early-life interventions to promote optimal lung growth and prevent development of chronic respiratory disease. Clinicians should play an active role, assisting individual patients in avoiding known detrimental exposures including maternal smoking during pregnancy and initiation of active smoking. Clinicians can be empowered by evidence to support policies promoting reduction of population-level risk factors, such as restriction on electronic cigarette sales and legislation to uphold air quality standards, to encourage attainment of maximal lung function and reduce risk of chronic lung disease.

Factors and mechanisms contributing to the development of preschool wheezing disorders

INTRODUCTION

Half of all children will experience an episode of wheezing by their sixth birthday and acute episodes of wheezing in preschool children account for the majority of all childhood hospital admissions for wheeze. Recurrent preschool wheezing associates with early loss of lung function and a life-long impact on lung health.

AREAS COVERED

We reviewed the literature on PubMed from August 2010-2020 focussing on factors associated with wheeze inception and persistence, paying specific attention to mechanistic studies that have investigated the impact of early life exposures in shaping immune responses in children with underlying susceptibility to wheezing. In particular, the role of early allergen sensitization, respiratory infections, and the impact of the environment on shaping the airway microbiome and resulting immune responses are discussed.

EXPERT OPINION

There is an abundance of associative data showing the role of in utero and postnatal factors influencing wheeze onset and persistence. However, mechanistic and stratified, biomarker-based interventional studies that confirm these associations are now needed if we are to impact the significant healthcare burden resulting from preschool wheezing disorders.

Impaired Respiratory Health and Life Course Transitions From Health to Chronic Lung Disease

Primary prevention and interception of chronic lung disease are essential in the effort to reduce the morbidity and mortality caused by respiratory conditions. In this review, we apply a life course approach that examines exposures across the life span to identify risk factors that are associated with not only chronic lung disease but also an intermediate phenotype between ideal lung health and lung disease, termed "impaired respiratory health." Notably, risk factors such as exposure to tobacco smoke and air pollution, as well as obesity and physical fitness, affect respiratory health across the life course by being associated with both abnormal lung growth and lung function decline. We then discuss the importance of disease interception and identifying those at highest risk of developing chronic lung disease. This work begins with understanding and detecting impaired respiratory health, and we review several promising molecular biomarkers, predictive symptoms, and early imaging findings that may lead to a better understanding of this intermediate phenotype.

Sex dependent effect of maternal e-nicotine on F1 Drosophila development and airways

E-cigarettes are heavily advertised as healthier alternative to common tobacco cigarettes, leading more and more women to switch from regular cigarettes to ENDS (electronic nicotine delivery system) during pregnancy. While the noxious consequences of tobacco smoking during pregnancy on the offspring health are well-described, information on the long-term consequences due to maternal use of e-cigarettes do not exist so far. Therefore, we aimed to investigate how maternal e-nicotine influences offspring development from earliest life until adulthood. To this end, virgin female Drosophila melanogaster flies were exposed to nicotine vapor (8 µg nicotine) once per hour for a total of eight times. Following the last exposure, e-nicotine or sham exposed females were mated with non-exposed males. The F1-generation was then analyzed for viability, growth and airway structure. We demonstrate that maternal exposure to e-nicotine not only leads to reduced maternal fertility, but also negatively affects size and weight, as well as tracheal development of the F1-generation, lasting from embryonic stage until adulthood. These results not only underline the need for studies investigating the effects of maternal vaping on offspring health, but also propose our established model for analyzing molecular mechanisms and signaling pathways mediating these intergenerational changes.

Use of e-Cigarettes and Development of Respiratory Conditions in Women of Childbearing Age

OBJECTIVE

Women of childbearing age are encouraged not to smoke because of well-documented adverse health outcomes. This study examines the association between e-cigarette use and respiratory conditions (asthma and chronic obstructive pulmonary disease [COPD]) among women of childbearing age.

METHODS

The study used data from the Behavioral Risk Factor Surveillance System 2016-2017. The sample consisted of 131,965 women of childbearing age (18-44 years old). The main independent variable was smoking status and the primary outcomes were self-reported respiratory conditions such as asthma and COPD. Data were analyzed using descriptive statistics and multivariate logistic regression to assess the effects of e-cigarettes on asthma and COPD.

RESULTS

In this sample of childbearing-age women, 2.79% were current e-cigarettes users with or without a history of combustible cigarette smoking and 3.02% were current dual users. Compared with nonsmokers, current e-cigarette users without a history of combustible cigarette smoking were associated with 74% higher odds of having asthma (adjusted odds ratio [AOR] 1.74, 95% confidence interval [CI] 1.29-2.35), whereas results were not significant for COPD. The odds of having COPD, however, were 3 times higher (AOR 3.28, 95% CI 2.62-4.12) for current e-cigarette users with a history of cigarette smoking, whereas current dual users showed 5 times higher odds (AOR 5.07, 95% CI 3.91-6.56) of COPD compared with nonsmokers.

CONCLUSION

Policies related to e-cigarettes need to be reevaluated and clearly communicated to improve prevention efforts for women of childbearing age.

Study on E-Cigarettes and Pregnancy (STEP) - Results of a Mixed Methods Study on Risk Perception of E-Cigarette Use During Pregnancy

Introduction E-cigarette use during pregnancy is a risk factor for maternal and fetal health. Early studies on animals showed that in utero exposure to e-cigarettes can have negative health outcomes for the fetus. There has been only limited research into the risk perceptions of e-cigarette use during pregnancy. This study was conducted to comprehensively characterize the constructs of risk perceptions with regard to e-cigarette use during pregnancy using an I ntegrated H ealth B elief M odel (IHBM).

Methods Our ST udy on E -cigarettes and P regnancy (STEP) used a mixed methods approach, with the study divided into an initial qualitative part and a quantitative part. A netnographic approach was used for the first part, which consisted of the analysis of 1552 posts from 25 German-language online discussion threads on e-cigarette use during pregnancy. Using these qualitative results, a quantitative questionnaire was developed to explore risk perception constructs about e-cigarette use during pregnancy. This questionnaire was subsequently administered to pregnant women (n = 575) in one hospital in Hamburg, Germany. Descriptive and bivariate analysis was used to examine differences in risk perception according to participantsʼ tobacco and e-cigarette user status before and during pregnancy. While the study design, methods and sample have been extensively described in our recently published study protocol in the January 2020 issue of Geburtshilfe und Frauenheilkunde , this paper is devoted to a presentation of the results of our mixed methods study.

Results Themes related to perceived threats identified in the qualitative study part were nicotine-related health risks and potential health risks of additional ingredients . Perceived benefits were possibility and facilitation of smoking cessation and a presumed potential to reduce harm . The subsequent quantitative part showed that nearly all participants (99.3%) perceived e-cigarettes which contained nicotine as constituting a threat to the health of the unborn child. The most commonly perceived barrier was health-related (96.6%), while the most commonly perceived benefit was a reduction in the amount of tobacco cigarettes consumed (31.8%). We found that particularly perceived benefits varied depending on the participantʼs tobacco and e-cigarette user status.

Conclusion When considering future prevention strategies, the potential health risks and disputed effectiveness of e-cigarettes as a tool for smoking cessation need to be taken into account and critically discussed.

Risk perception of cigarette and e-cigarette use during pregnancy: A qualitative postpartum perspective

AIM

The aim of this exploratory qualitative analysis is to assess the perceptions of risks of cigarette and e-cigarette use during pregnancy.

BACKGROUND

An important public health aim is a reduction of smoking at time of delivery (SATOD) from 10.6% to less than 6% by 2022 in the United Kingdom (UK). In order to successfully meet this target, we need to have a better understanding of the perceived risks associated with cigarette smoking. Additionally, the use of e-cigarettes is increasing in the general population, with pregnant women being supported to use such products if it helps them remain smoke free. However, in contrast to cigarette smoking, there is little definitive research assessing the safety of e-cigarette use during pregnancy, with most information disregarding the health of the growing fetus. E-cigarettes are of special interest, given they are an unlicensed product for use during pregnancy, yet women are being supported to use them as a method of harm reduction. A better understanding of perceived risks is essential.

METHOD

Fourteen interviews were conducted one month postpartum with women who smoked during pregnancy and continued to smoke after the birth. Thematic analysis was conducted.

FINDINGS

Two themes emerged for cigarette smoking; health and justifications. Six themes were identified for e-cigarette use; the unknown, experience, comparison to cigarettes, the product, advice and healthier option. A range of subthemes are discussed.

CONCLUSION

Women provided a range of justifications for continuing to smoke during pregnancy. Women felt e-cigarettes were a riskier option than continuing to smoke.

Influence of microbiota and metabolites on the quality of tobacco during fermentation

BACKGROUND

To explore the optimum fermentation conditions for tobacco leaves and also screen the microbiota and metabolites that are beneficial for fermentation.

METHODS

Tobacco leaves were fermented at 25 °C, 35 °C, and 45 °C for 2, 4, and 6 weeks, respectively. For identification of the best fermentation temperature, physicochemical properties and sensory quality of fermented tobacco were investigated. Subsequently, based on the appropriate temperature, 16 s rRNA sequencing and metabolomics analysis of tobacco were performed to monitor the change of microbes and metabolites during fermentation process (from 2 to 6 weeks).

RESULTS

Sensory quality analysis indicated that fermentation at 45 °C for 6 weeks represented the optimum condition. Metabolomics analysis showed that a total of 415 metabolites were annotated. The increase of fermentation period led to significant changes of metabolites. Results revealed an increase in concentration of L-phenylalanine and sphingosine as well as decreased concentration of betaine and phytosphingosine with the prolongation of fermentation period (2 to 6 weeks). Distinct changes in the microbiota were also observed with prolongation of the fermentation time. Results revealed that Pseudomonas, Pantoea, and Burkholderia were dominant bacteria in fermentation at 45 °C for 6 weeks. With the extension of the fermentation time, the abundance of Pseudomonas increased, while that of Sphingomonas and Methylobacterium decreased. Furthermore, microbiota profiles were tightly relevant to the altered metabolites, especially compounds involved in the sphingolipid metabolism.

CONCLUSION

Suitable fermentation conditions were 45 °C for 6 weeks; phytosphingosine and sphingosine might affect tobacco fermentation via the sphingolipid metabolism pathway. This study provides a theoretical basis for guiding tobacco fermentation and gives insights into reducing harmful substances during tobacco fermentation.

Effect of prenatal cigarette smoke exposure on sevoflurane-induced respiratory suppression in neonatal rats and the protective role of hydrogen sulfide

Prenatal cigarette smoke (CS) exposure causes numerous respiratory health problems in infants. This study aimed to investigate the effect of prenatal CS exposure on sevoflurane-induced respiratory suppression in neonatal rats and the protective role of H₂S. We found that at baseline, minute ventilation (V'_E), respiratory frequency (f_R), and tidal volume (V_T) were similar among tested groups, whereas sigh frequency (f_S) was lower in CS group than in the Control group. During 3 % sevoflurane anesthesia, V'_E was decreased, f_R was slowed, V_T was increased, and f_S was reduced in all groups; however, the decline in f_R and increase in V_T was greater in CS group than in the Control group. During the recovery, f_S remained lower in CS group. The above changes of respiratory response caused by prenatal CS exposure were alleviated by NaHS pretreatment (a donor of H₂S, 56 μmol/kg/d, intraperitoneal injection). These results indicated that prenatal CS exposure alters the breathing into a much slower and deeper manner in neonatal rats during sevoflurane anesthesia, and H₂S mitigates this respiratory change.

Gestational Women's Perceptions About the Harms of Cigarette and E-Cigarette Use During Pregnancy

OBJECTIVES

The purpose of this study was to examine differences between perceived harm of cigarette and electronic cigarette (e-cigarette) use while pregnant and differences between healthcare providers' communication about these products during pregnancy.

METHODS

A convenience sample of gestational women (n = 218; ages 18-45) living in the US completed an online survey between May and December 2017. Participants reported perceived likelihood of adverse health outcomes (e.g., low birth weight, sudden infant death syndrome) among infants/children born to mothers who used cigarettes/e-cigarettes. T-tests and two-way ANOVAs examined differences between risk perceptions of using cigarettes/e-cigarettes while pregnant based on pregnancy status (previously pregnant, currently pregnant, future pregnant). Chi-square analyses examined differences between healthcare provider communication about cigarette/e-cigarette use during pregnancy.

RESULTS

Overall, participants believed adverse health outcomes were significantly more likely to be caused by maternal use of cigarettes than e-cigarettes. Participants who planned to be pregnant reported higher endorsement that smoking combustible cigarettes would cause a miscarriage (p < .05) or increased blood pressure (p < .05) for a child than currently pregnant participants. Participants reported healthcare providers asked about (p < .05), advised them not to use (p < .001), and talked to them about health effects of smoking combustible cigarettes while pregnant (p < .001) significantly more than e-cigarettes.

CONCLUSIONS FOR PRACTICE

Healthcare providers working with pregnant women should perform the 5As behavioral intervention method to provide pregnant women with tobacco cessation care. They should also discuss the absolute harm nicotine exposure (via cigarettes or e-cigarettes) can have on fetal health and development.

Early Life Exposure to Nicotine: Postnatal Metabolic, Neurobehavioral and Respiratory Outcomes and the Development of Childhood Cancers

Cigarette smoking during pregnancy is associated with numerous obstetrical, fetal, and developmental complications, as well as an increased risk of adverse health consequences in the adult offspring. Nicotine replacement therapy and electronic nicotine delivery systems (e-cigarettes) have been developed as a pharmacotherapy for smoking cessation and are considered safer alternatives for women to smoke during pregnancy. The safety of nicotine replacement therapy use during pregnancy has been evaluated in a limited number of short-term human trials, but there is currently no information on the long-term effects of developmental nicotine exposure in humans. However, animal studies suggest that nicotine alone may be a key chemical responsible for many of the long-term effects associated with maternal cigarette smoking on the offspring and increases the risk of adverse neurobehavioral outcomes, dysmetabolism, respiratory illness, and cancer. This review will examine the long-term effects of fetal and neonatal nicotine exposure on postnatal health.

Trajectories of Lung Function in Infants and Children: Setting a Course for Lifelong Lung Health

For healthy individuals, it is increasingly accepted that lung function follows along an individual percentile established early in life and that the level of maximal function reached as a young adult can affect the subsequent development of lung disease that occurs with the normal aging process. This emphasizes the need to maximize early lung function. The trajectories of lung function are at least partially established by perinatal factors, including prematurity and in utero exposures (tobacco exposure, nutrition, inflammation, etc), although they can also be affected by a variety of additional factors and exposures throughout the life span. Whether lung function trajectories can be impacted or reset if established under suboptimal conditions is an unanswered question, offering new avenues for research. In this review, we will summarize important articles outlining lung function trajectories and linking pediatric lung function tests to adult lung function tests decades later. We will focus on perinatal factors and outline progress and opportunities for further investigation into the potential ability to reset trajectories to impact long-term lung health.

Perceived harms of and exposure to tobacco use and current tobacco use among reproductive-aged women from the PATH study

Data for this study were obtained from reproductive-aged women (aged 18-44 years, at wave 1) from waves 1 (2013-2014) and 2 (2014-2015) of the Population Assessment of Tobacco and Health Study (n = 13,241). Bivariate and multinomial regression analyses were performed associating past 30-day use of cigarettes only, e-cigarettes only, and dual use with perceptions of harm, exposure to tobacco product use, and sociodemographic variables. Cross-sectional and longitudinal analyses were conducted. Of all reproductive-aged women included in the analyses, 75.5 percent reported no tobacco use, 16.9 percent reported cigarette use only, 1.5 percent reported e-cigarette use only, and 6.1 percent reported dual use within the past 30 days. Perceived harm, tobacco exposure, pregnancy status, age, race/ethnicity, income, education, and sexual orientation were associated with the past 30-day use, cross-sectionally at wave 1. Similar associations were found for longitudinal analyses using wave 2 data, except for income and education, which were no longer associated. The results of this study contribute to knowledge regarding the prevalence and correlates of tobacco use across exclusive cigarette, exclusive e-cigarette, and dual use among reproductive-aged women.

Changes in Multiple and Different Tobacco Product Use Behaviors in Women Before and During Pregnancy: An Analysis of Longitudinal Population Assessment of Tobacco and Health Data

INTRODUCTION

Changes in tobacco use behaviors among women with respect to pregnancy are expected to be significant and dynamic, with a strong desire for smoking cessation, diversification of tobacco products, and perceived relative safety on noncigarette tobacco products. This study aims to illustrate how multiple and different tobacco use behaviors change before and during pregnancy.

METHODS

Data were extracted from 864 pregnant, nationally representative U.S. women, who were prospectively followed with the Population Assessment of Tobacco and Health study between 2013 and 2017. Smoking statuses were defined on the basis of the number and type of 7 different tobacco products under current use. Differences in maternal characteristics were investigated in relation to tobacco cessation statuses during pregnancy. Weighted percentages and 95% CIs were calculated.

RESULTS

Only 50.4% of prepregnancy tobacco users achieved complete abstinence with varying rates of cessation, depending on the number and type of products used prepregnancy. The lowest cessation rates were observed among prepregnancy poly-tobacco users (23.3%) and conventional cigarette smokers (45.5%). During pregnancy, 11.3% and 2.8% of women reported smoking cigarettes and e-cigarettes, respectively. Persistent tobacco users during pregnancy were more likely to be white, be older, and have nonprivate or no medical insurance (all p<0.05).

CONCLUSIONS

This study demonstrates a widespread prenatal tobacco use and low rates of complete cessation in major subgroups of tobacco users. Current findings on the concurrent use of multiple products and noncigarette tobacco products highlight the urgent need for further research and comprehensive public health intervention for smoking cessation during pregnancy.