Prenatal Versus Postnatal Tobacco Smoke Exposure and Intensive Care Use in Children Hospitalized With Bronchiolitis

[The impact of maternal smoking during pregnancy on respiratory disease in children]

Among the causes of abnormal fetal lung development, active and environmental maternal smoking represents a major potential target in preventive medicine. Prevalence of smoking among women, particularly during pregnancy, varies across the different regions of the world. We reviewed the literature on the repercussions of maternal smoking on the lungs of the fetus and the neonate. One of the main consequences is prematurity, leading to pulmonary bronchodysplasia followed by respiratory infections, which particularly affect young children. In the medium- and long-term, smoking in utero leads to asthma and allergies, and is suspected to be associated with impaired respiratory function in children and teenagers. We also report on the potential effects of e-cigarettes, which represent an emerging threat to children's respiratory health.

Assessment of the Relationship Between Smoking and Depression in Pregnant Women

Smoking during pregnancy has negative effects on both maternal and fetal health. One of these negative maternal effects is the potential for depression. A high rate of cigarette smoking in pregnancy is an important public health issue since it affects not only the pregnant woman but also the newborn and its healthy development. The aim of this study is to investigate the relationship between smoking, influencing factors, and depression prevalence in pregnant Syrian refugees and pregnant citizens of the Republic of Turkey (TR). Pregnant citizens in the TR and pregnant Syrian refugees who were registered at health centers between 15.04.2017 and 15.10.2017 in the border city of Ceylanpınar in the Province of Şanlıurfa in Syria were visited in their living areas in the district center and at a tent village, respectively. A total of 414 pregnant women agreed to participate in the study and were included in the survey. To collect data for the cross-sectional study, a sociodemographic and pregnancy characteristics questionnaire was used, in addition to the Fageström Test for Nicotine Dependence (FTND) and the Beck Depression Inventory (BDI). The rate of smoking in all pregnant women was determined to be 49.3% (n = 204) before pregnancy and 37.9% (n = 157) during pregnancy. A statistically significant difference was found between age groups and educational status in relation to smoking status (p = 0.005, p = 0.001). There was also a statistically significant difference between the smoking status of pregnant women and that of their partners and family members (p = 0.001, p = 0.002). The percentage of pregnant women who were passive smokers was 80.2% (n = 332), and a statistically significant difference was found between passive smoking and smoking status (Fisher; 0.000). The presence of risk for depression was detected in 49.8% (n = 206) of all pregnant women surveyed; the rate of depression risk was 50.5% (n = 104) in pregnant TR citizens and 49.5% (n = 102) in pregnant refugees, with no significant difference between the two groups. There was a statistically significant difference between smoking status in pregnancy and the presence of depression risk (p = 0.001). 32.5% of pregnant women were highly nicotine dependent. A moderate positive correlation was determined between the FTND and BDI scores of pregnant women (r = 0.346; p = 0.001). It was found that one-third of all pregnant women smoked and that one of every two showed a risk for depression. A statistically significant correlation was found between smoking status and risk for depression. No statistically significant difference was determined between the two groups, despite high levels of smoking, nicotine dependence, and depression in both. These data suggest the need to develop new preventive strategies in regard to smoking among pregnant women.

Severity of bronchiolitis in infants is associated with their parents' tobacco habit

The aim of this study was to investigate the effect of tobacco smoke exposure among severely pediatric ICU patients. A prospective epidemiological observational study was conducted among children with bronchiolitis younger than 2 years of age admitted to the Pediatric Intensive Care Unit of Children's University Hospital La Paz during the October 2017 to March 2018 outbreak. On admission, parents were asked whether they smoked. In children who required invasive mechanical ventilation, endotracheal aspirate was collected at the time of intubation. A total of 102 patients with bronchiolitis were studied. Among these, 14 (47%) of 30 infants whose parents smoked required invasive mechanical ventilation vs. 14 (19%) of 72 whose parents were nonsmokers (p = 0.007). Among patients on invasive mechanical ventilation, 10 (71%) of 14 infants with secondhand smoke exposure presented pulmonary bacterial superinfection vs. 3 (21%) of 14 in the unexposed (p = 0.012).Conclusion: Secondhand smoke exposure is an additional high risk for pulmonary bacterial superinfection and invasive mechanical ventilation in infants with severe acute bronchiolitis What is known: •Environmental tobacco smoke exposure is known to be an important risk factor for childhood lower respiratory tract infections. •Tobacco smoke makes structural changes in the respiratory tract and reduces the immune response. What in new: •Secondhand smoke exposure showed to be associated with the increased need and duration of invasive mechanical ventilation, and pediatric intensive care length of stay. •Tobacco smoke exposure is an additional risk factor for the presence of bacteria in the endotracheal aspirate.

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.

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.

Respiratory Symptoms and Urinary Cotinine Levels in Pre-school Children Exposed to Environmental Tobacco Smoke

Objective: Preschool children exposed to environmental tobacco smoke (ETS) are at risk of developing adverse respiratory health effects. The present study aimed to investigate the relationship between the effects of cigarette-smoking caregivers on respiratory symptoms and urinary cotinine (UC) levels in children. Methods: A cross-sectional study consisting of 543 children (aged between 5 and 6 years) from 5 kindergartens in central China was conducted using a structured questionnaire. We also analyzed UC levels to investigate the relationship between respiratory symptoms and ETS exposure. We further performed logistic regression analyses to establish the relationship between respiratory symptoms (coughing, rhinorrhea, and sneezing) and UC levels. Results: A total of 71 (13.08%) children had a history of hospital admission with respiratory illnesses including bronchitis and pneumonia over the last 6 months. In addition, 102 (18.78%) children presented coughing symptoms, 114 (20.99%) experienced rhinorrhea and 79 (14.55%) presented sneezing symptoms over the last 6 months. After adjusting the confounders, odds ratio (OR) indicated that the number of cigarettes smoked by a caregiver was associated with coughing (OR = 11.02; 95% CI, 3.72-33.66), rhinorrhea (OR = 41.83; 95% CI, 5.58-313.05) and sneezing (OR = 4.71; 95% CI, 1.33-16.48). Furthermore, UC levels in children with coughing, rhinorrhea and sneezing were significantly higher than in children without respiratory symptoms (P = 0.002, P < 0.001, P < 0.001, respectively). Conclusions: This study reveals that children exposed to ETS have higher levels of UC. Compared with caregiver who non-smoked live with children, smoked cigarettes were highly risk of developing respiratory illnesses in children. Notably, the higher the UC levels the greater the respiratory risk. Our results also signify that UC can be used as an indicator of ETS exposure to inform caregivers of the associated risks, and inform efforts to reduce related effects.

Respiratory syncytial virus infection: why does disease severity vary among individuals?

Introduction: Respiratory syncytial virus (RSV) is the most common cause of acute lower respiratory tract infections in infancy. While many infants are infected with RSV, the nature and severity of the disease vary among individuals. RSV causes bronchiolitis, pneumonia, and asthma exacerbation. However, most children infected with RSV have only mild upper airways disease and may be asymptomatic.Areas covered: Despite efforts to elucidate mechanisms for the various clinical responses to RSV infection, they remain largely unknown, suggesting that susceptibility and disease are influenced by multiple intrinsic and extrinsic factors. This article reviews the available literature on the field of RSV disease severity and discusses important factors associated to susceptibility and different disease outcome.Expert opinion: The severity of RSV-induced illness is a phenomenon that depends on a variety of graded mechanisms of interaction between the host, virus, and environment. This may lead to differences in the intensity of immune response in the lung and different courses of the disease. By characterizing, classifying, and grading the affecting factors in high-risk patients versus those who do not fall ill by RSV, we may find therapies or point to disease-limiting medications.

In utero tobacco smoke exposure alters lung inflammation, viral clearance, and CD8+T-cell responses in neonatal mice infected with respiratory syncytial virus

Maternal smoking during pregnancy and exposure of infants to cigarette smoke are strongly associated with adverse health effects in childhood including higher susceptibility to respiratory viral infections. Human respiratory syncytial virus (HRSV) is the most important cause of lower respiratory tract infection among young infants. Exacerbation of respiratory disease, including HRSV bronchiolitis and higher susceptibility to HRSV infection, is well correlated with previous smoke exposure. The mechanisms of recurrence and susceptibility to viral pathogens after passive smoke exposure are multifactorial and include alteration of the structural and immunologic host defenses. In this work, we used a well-established mouse model of in utero smoke exposure to investigate the effect of in utero smoke exposure in HRSV-induced pathogenesis. Sample analysis indicated that in utero exposure led to increased lung inflammation characterized by an increased influx of neutrophils to the airways of the infected mice and a delayed viral clearance. On the other hand, decreased HRSV-specific CD8+T-cell response was observed. These findings indicate that cigarette smoke exposure during pregnancy alters HRSV-induced disease as well as several aspects of the neonatal immune responses.

Black Race Is Associated with a Lower Risk of Bronchopulmonary Dysplasia

OBJECTIVE

To use a large current prospective cohort of infants <29 weeks to compare bronchopulmonary dysplasia (BPD) rates in black and white infants.

STUDY DESIGN

The Prematurity and Respiratory Outcome Program (PROP) enrolled 835 infants born in 2011-2013 at <29 weeks of gestation; 728 black or white infants survived to 36 weeks postmenstrual age (PMA). Logistic regression was used to compare BPD outcomes (defined as supplemental oxygen requirement at 36 weeks PMA) between the races, adjusted for gestational age (GA), antenatal steroid use, intubation at birth, and surfactant use at birth.

RESULTS

Of 707 black or white infants with available BPD outcomes, BPD was lower in black infants (38% vs 45%), even though they were of significantly lower GA. At every GA, BPD was more common in white infants. The aOR for BPD was 0.60 (95% CI, 0.42-0.85; P = .004) for black infants compared with white infants after adjusting for GA. Despite the lower rate of BPD, black infants had a higher rate of first-year post-prematurity respiratory disease (black, 79%; white, 63%).

CONCLUSIONS

In this large cohort of recently born preterm infants at <29 weeks GA, compared with white infants, black infants had a lower risk of BPD but an increased risk of persistent respiratory morbidity.

Predictors of Critical Care and Mortality in Bronchiolitis after Emergency Department Discharge

OBJECTIVES

To identify the epidemiologic predictors and stratify the risk of critical care unit (CCU) admission or death in bronchiolitis following emergency department discharge. This information has not yet been explored.

STUDY DESIGN

A population-based cohort study using Ontario-wide demographic and healthcare databases linked at the individual level. We assessed all infants with bronchiolitis discharged home from all emergency departments in Ontario, Canada, 2003-2014. Targeted information included plausible demographic and clinical predictors of CCU admission/death within 14 days of emergency department discharge. Using multivariable logistic regression analyses, we identified independent predictors of this outcome and stratified the outcome risk by the type of multivariable predictor.

RESULTS

Of 34 270 study infants, 102 (0.3%) were admitted to CCU or died after discharge. Predictors of CCU admission/death were: comorbidities (OR 5.33; 95% CI 2.82-10.10), younger age [months] (OR 1.47; 95%CI 1.33-1.61), low income (OR 1.53; 95% CI 1.01-2.34), younger gestational age [weeks] (OR 1.14; 95%CI 1.06-1.22), and emergent presentation (Canadian Triage and Acuity Scale 2) at the index visit (OR 1.55, 95% CI 1.03-2.33). The absolute event risk of CCU admission/death in infants with versus without comorbidities were 1.5% versus 0.26%, respectively (P < .001). The odds of these outcomes in infants with comorbidities plus ≥2 other predictors were 25 times higher than in infants without predictors (OR 25.1, 95% CI 11.4-55.3).

CONCLUSIONS

Infants with comorbidities plus other predictors discharged from the emergency department with bronchiolitis are at considerable risk of subsequent CCU admission and death. These risk factors should augment current clinical and social considerations determining patient disposition.

Prenatal and postnatal tobacco smoke exposure and risk of severe bronchiolitis during infancy

BACKGROUND

Maternal prenatal smoking has adverse effects on the growing fetus including those of respiratory nature. Although postnatal smoke exposure is a risk factor for respiratory infections, the effects of prenatal smoking independent of postnatal smoke exposure are less established. We hypothesized that both maternal prenatal smoking, and postnatal smoke exposure are risk factors for severe bronchiolitis during infancy.

METHODS

We performed a case-control study of 1353 children born between 1996 and 2011 at a single teaching hospital. Cases were admitted to the same hospital for bronchiolitis during infancy. Maternal prenatal smoking was collected from birth records. Postnatal smoke exposure was collected from review of electronic health records. Multivariable logistic regression was used to evaluate the independent associations of the two smoking variables with severe bronchiolitis.

RESULTS

6% of cases were exposed to maternal prenatal smoking, compared with 4% of controls (P = 0.10). Postnatal smoke exposure was present in the households of 17% of cases compared with 3% of controls (P < 0.001). In a multivariable model with both smoking variables and adjustment for 10 covariates, maternal prenatal smoking was not a significant risk factor for severe bronchiolitis (adjusted OR = 1.02, 95%CI 0.56-1.84). By contrast, postnatal smoke exposure was associated with >300% increased odds (adjusted OR 4.19, 95%CI 2.51-6.98).

CONCLUSIONS

Although maternal prenatal smoking has many known adverse effects, it was not associated with increased odds of severe bronchiolitis in either unadjusted or multivariable analyses. Postnatal smoke exposure was a consistently strong risk factor. Our findings support ongoing efforts to decrease infant exposure to ambient smoke.

Risk factors for asthma after infant bronchiolitis

BACKGROUND

Five studies carried out after bronchiolitis at less than 24 months of age, with a follow-up of more than 10 years, reported that atopic dermatitis, family asthma, early-life exposure to tobacco smoke and rhinovirus aetiology were early-life risk factors for later asthma. This study evaluated the long-term outcome at 11-13 years of age of children who were hospitalized for bronchiolitis in early infancy.

METHODS

We previously prospectively followed 166 children hospitalized for bronchiolitis at less than 6 months of age until 5-7 years of age. The current study included a structured questionnaire, parental interviews, clinical examinations and bronchodilation test of 138 of those children at 11-13 years of age.

RESULTS

Respiratory syncytial virus caused 66% of the bronchiolitis cases, and nearly half of the patients were exposed to tobacco smoke in early life. Doctor-diagnosed asthma was present in 13% of the former bronchiolitis patients at 11-13 years of age. Maternal asthma was the only independently significant risk factor in early life (adjusted OR 3.45, 95% CI 1.07-11.74), as was allergic rhinitis at 5-7 years of age (adjusted OR 4.06, 95% CI 1.35-12.25).

CONCLUSIONS

After bronchiolitis at less than 6 months of age, the risk of doctor-diagnosed asthma at 11-13 years was about twice that of the general Finnish population. Maternal asthma was the only independently significant early-life risk factor for current asthma at 11-13 years of age.

Factors Affecting the Immunity to Respiratory Syncytial Virus: From Epigenetics to Microbiome

Respiratory syncytial virus (RSV) is a common pathogen that infects virtually all children by 2 years of age and is the leading cause of hospitalization of infants worldwide. While most children experience mild symptoms, some children progress to severe lower respiratory tract infection. Those children with severe disease have a much higher risk of developing childhood wheezing later in life. Many risk factors are known to result in exacerbated disease, including premature birth and early age of RSV infection, when the immune system is relatively immature. The development of the immune system before and after birth may be altered by several extrinsic and intrinsic factors that could lead to severe disease predisposition in children who do not exhibit any currently known risk factors. Recently, the role of the microbiome and the resulting metabolite profile has been an area of intense study in the development of lung disease, including viral infection and asthma. This review explores both known risk factors that can lead to severe RSV-induced disease as well as emerging topics in the development of immunity to RSV and the long-term consequences of severe infection.

Secondhand smoke exposure, illness severity, and resource utilization in pediatric emergency department patients with respiratory illnesses

OBJECTIVE

Hospital-based data reveal that children who have secondhand smoke exposure (SHSe) experience severe respiratory illnesses and greater resource utilization. Our objective was to assess the relationship between SHSe and illness severity/resource utilization among children presenting to the pediatric emergency department (PED) with three common respiratory conditions-asthma, bronchiolitis, and pneumonia.

METHODS

A retrospective review of a yearlong consecutive sample of PED patients with SHSe status documentation and asthma, bronchiolitis, or pneumonia diagnoses was performed. PED illness severity/resource utilization variables included triage categorization, initial oxygen saturation, evaluation/testing (influenza A & B, respiratory syncytial virus, chest X-ray), procedures/interventions performed (supplemental oxygen, suctioning, intubation), medications administered, and disposition. Logistic and linear regression models were conducted to determine differences in each diagnosis group while controlling for sociodemographics, medical history, seasonality, and insurance type.

RESULTS

There were 3,229 children with documentation of SHSe status and an asthma (41%), bronchiolitis (36%), or pneumonia (23%) diagnosis. Across diagnosis groups, approximately 1/4 had positive documentation of SHSe. Asthmatic children with SHSe were more likely to receive corticosteroids (odds ratio (OR) = 1.71, 95% confidence interval (CI) = 1.19, 2.44) and/or magnesium sulfate (OR = 1.66, 95% CI = 1.14, 2.40). Children with SHSe and bronchiolitis were more likely to receive racemic epinephrine (OR = 2.48, 95% CI = 1.21, 5.08), have a chest X-ray (OR = 1.36, 95% CI = 1.00, 1.85), and/or be admitted (OR = 1.46, 95% CI = 1.09, 1.95). No differences in illness severity/resource utilization were identified for children with pneumonia.

CONCLUSIONS

SHS-exposed children with asthma or bronchiolitis have greater illness severity/resource utilization. Our findings highlight the importance of SHSe assessment, cessation, and research efforts in the PED setting.

The association between environmental tobacco smoke exposure and childhood respiratory disease: a review

INTRODUCTION

Childhood respiratory illness is a major cause of morbidity and mortality particularly in low and middle-income countries. Environmental tobacco smoke (ETS) exposure is a recognised risk factor for both acute and chronic respiratory illness. Areas covered: The aim of this paper was to review the epidemiology of ETS exposure and impact on respiratory health in children. We conducted a search of 3 electronic databases of publications on ETS and childhood respiratory illness from 1990-2015. Key findings were that up to 70% of children are exposed to ETS globally, but under-reporting may mask the true prevalence. Maternal smoking and ETS exposure influence infant lung development and are associated with childhood upper and lower respiratory tract infection, wheezing or asthma. Further, exposure to ETS is associated with more severe respiratory disease. ETS exposure reduces lung function early in life, establishing an increased lifelong risk of poor lung health. Expert commentary: Urgent and effective strategies are needed to decrease ETS exposure in young children to improve child and long-term lung health in adults especially in low and middle income countries where ETS exposure is increasing.

Prevention and Treatment of Smoking and Tobacco Use During Pregnancy in Selected Indigenous Communities in High-Income Countries of the United States, Canada, Australia, and New Zealand: An Evidence-Based Review

Tobacco smoking during pregnancy is the most important modifiable risk factor for adverse pregnancy outcomes and long-term health complications for mother and baby. Tobacco use during pregnancy has decreased in high-income countries but not in Indigenous women in Australia, New Zealand, the United States, and Canada. This evidence-based review focuses on tobacco use among Indigenous pregnant women in high-income countries that share a history of European colonization. Indigenous women are more likely to use tobacco because of socioeconomic disadvantage, social norms, and poor access to culturally appropriate tobacco cessation support. Complications arising from tobacco smoking during pregnancy, such as low birth weight, prematurity, perinatal death, and sudden infant death syndrome, are much higher in Indigenous populations. Effective approaches to cessation in pregnant nonindigenous women involves behavioral counseling, with or without nicotine replacement therapy (NRT). Higher nicotine metabolism during pregnancy and poor adherence may affect therapeutic levels of NRT. Only two randomized trials were conducted among Indigenous women: neither found a statistically significant difference in cessation rates between the treatment and comparison arms. Considerations should be given to (1) whole life course approaches to reduce tobacco use in Indigenous women, (2) prohibiting tobacco promotion and reducing access to alcohol for minors to prevent smoking initiation in Indigenous youth, and (3) training health-care professionals in culturally appropriate smoking cessation care to improve access to services. It is critical to ensure acceptability and feasibility of study designs, consult with the relevant Indigenous communities, and preempt implementation challenges. Research is needed into the effect of reducing or stopping smoking during pregnancy when using NRT on subsequent maternal and infant outcomes.

A Preliminary Assessment of the Role of Ambient Nitric Oxide Exposure in Hospitalization with Respiratory Syncytial Virus Bronchiolitis

Some in vitro studies have indicated a possible link between respiratory syncytial virus (RSV) infection and exposure to Nitric Oxide (NO). However, these studies used much higher NO concentrations than normally found in the ambient environment. This preliminary study explored whether an association was present with short-term exposure to NO in the environment. RSV-related admission data between November 2011 and February 2012 were obtained from Sheffield Children's Hospital. The dates of admission were linked to contemporaneous ambient NO derived from sentinel air monitors. The case-crossover design was used to study the relationship between daily RSV admissions and NO, controlling for temperature and relative humidity. We found little evidence of association between daily RSV admission rates and exposure to ambient NO at different lags or average exposure across several lags. The findings should, however, be viewed with caution due to the low number of events observed during the time frame. It is possible that the apparent lack of association may be accounted for by the timing of the seasonal RSV epidemic in relation to peaks in NO concentrations. A larger study incorporating a wider range of RSV and NO peaks would determine whether said peaks enhanced the number of RSV hospitalizations in children.