Maternal smoking during pregnancy and postnatal exposure to environmental tobacco smoke as predisposition factors to acute respiratory infections

Alarming Trend in Under-Five Indian Children's Exposure to Indoor Tobacco Smoke

BACKGROUND AND AIM

Children who are exposed to tobacco smoke (ETS) are at risk for a variety of health issues. There are enough legislative provisions in Indian law to safeguard children from ETS in outdoor settings, but no such specific rules exist to shield them from exposure indoors. This study aimed to examine the trend in under-five children's exposure to indoor tobacco smoke over the course of a decade (from 2005 to 2016) in India.

MATERIALS AND METHODS

Data from the National Family and Health Survey (NFHS) for the years 2005-2006 (NFHS-3) and 2015-2016 (NFHS-4) on under-five children have been taken into consideration in cross-sectional analyses of the Demographic and Health Survey on India. Based on different sociodemographic factors, the propensity of indoor ETS among Indian children has been estimated and compared using both bivariate and multivariate logistic regression models.

RESULTS

The prevalence of indoor ETS among Indian children under the age of five has greatly risen over the past decade, rising from 4.12% to 52.70%. According to the findings, there has been a noticeable increase in every group of kids, regardless of their age, place of residence, geographic location, socioeconomic status, and literacy level of their mothers.

CONCLUSION

In India, the incidence of indoor ETS among children under five has risen by 13 times in the last 10 years, endangering the country. As a result, the Indian government must prepare to take legislative action to safeguard children by passing laws that forbid smoking inside.

Modeling the effects of cigarette smoke extract on influenza B virus infections in mice

Influenza B virus (IBV) is a major respiratory viral pathogen. Due to a lack of pandemic potential for IBV, there is a lag in research on IBV pathology and immunological responses compared to IAV. Therefore, the impact of various lifestyle and environmental factors on IBV infections, such as cigarette smoking (CS), remains elusive. Despite the increased risk and severity of IAV infections with CS, limited information exists on the impact of CS on IBV infections due to the absence of suitable animal models. To this end, we developed an animal model system by pre-treating mice for two weeks with cigarette smoke extract (CSE), then infected them with IBV and monitored the resulting pathological, immunological, and virological effects. Our results reveal that the CSE treatment decreased IBV specific IgG levels yet did not change viral replication in the upper airway/the lung, and weight recovery post infection. However, higher concentrations of CSE did result in higher mortality post infection. Together, this suggests that CS induced inflammation coupled with IBV infection resulted in exacerbated disease outcome.

Interactions of genetic variants and prenatal stress in relation to the risk for recurrent respiratory infections in children

Genetic variants may predispose children to recurrent respiratory infections (RRIs) but studies on genotype-environment interaction are rare. We hypothesized that the risk for RRIs is elevated in children with innate immune gene variants, and that prenatal exposure to maternal psychological distress further increases the risk. In a birth cohort, children with RRIs (n = 96) were identified by the age of 24 months and compared with the remaining cohort children (n = 894). The risk for RRIs in children with preselected genetic variants and the interaction between maternal distress during pregnancy and child genotype were assessed with logistic regression. The IL6 minor allele G was associated with elevated risk for RRIs (OR 1.55; 95% CI 1.14-2.12). Overall, there was no interaction between maternal psychological distress and child genotype. Exploratory analyses showed that, the association between the variant type of IL6 and the risk for RRIs was dependent on prenatal exposure to maternal psychological distress in males (OR 1.96; 95% CI 1.04-3.67). Our study didn't find genotype-environment interaction between prenatal maternal distress and child genotype. Exploratory analyses suggest sex differences in gene-environment interaction related to susceptibility to RRIs.

Effects of parental smoking and indoor tobacco smoke exposure on respiratory outcomes in children

The extensive literature has reported adverse effects on environmental tobacco smoke (ETS) on children's health. We aim to analyze associations of ETS with dry night cough, croup, pneumonia, and frequent common cold and to disentangle the effects of prenatal, infancy and childhood exposure by multilevel logistic regression. A cross-sectional study was conducted among 41,176 children aged 3-8 years in 8 major cities of China during 2010-2011, and obtained demographic information, smoke exposure information, and respiratory outcomes. Parents' smoking habit and indoor tobacco smoke odor were considered as two indicators of ETS. The prevalences of respiratory outcomes were 6.0% for croup, 9.5% for frequency common cold, 17.1% for dry night cough and 32.3% for pneumonia respectively in the study. The associations between respiratory outcomes and parental smoking were not obvious, while indoor tobacco smoke odor was clearly and strongly associated with most respiratory outcomes, with adjusted odds ratios ranging from 1.06 to 1.95. Both infancy and childhood exposure to tobacco smoke odor were independent risk factors, but infancy exposure had a higher risk. The results explore that ETS increased the risk of respiratory outcomes in children, highlighting the need for raising awareness about the detrimental effects of tobacco smoke exposure.

Prenatal Maternal Psychological Distress and Offspring Risk for Recurrent Respiratory Infections

OBJECTIVE

To assess the relation between maternal prenatal psychological distress, comprising depression and anxiety symptoms and relationship quality, and the risk of recurrent respiratory infections (RRIs) in children up to 2 years of age. Children with RRIs frequently use health care services and antibiotics. Prenatal maternal psychological distress can be one, previously unidentified risk factor for RRIs.

STUDY DESIGN

The study population was drawn from a population-based pregnancy cohort in Finland (www.finnbrain.fi). Children with RRIs (n = 204) and a comparison group (n = 1014) were identified by maternal reports at the child age of 12 or 24 months. The Edinburgh Postnatal Depression Scale, Symptom Checklist-90 anxiety subscale, the Pregnancy-Related Anxiety Questionnaire-Revised 2, and the Revised Dyadic Adjustment Scale were used to assess maternal symptoms and parental relationship quality at 34 weeks of gestation. Adjustment for maternal postnatal depressive and anxiety symptoms was performed.

RESULTS

Maternal prenatal Edinburgh Postnatal Depression Scale (OR, 1.24; 95% CI, 1.08-1.44), Symptom Checklist-90/Anxiety (OR, 1.40; 95% CI, 1.01-1.76), Pregnancy-Related Anxiety Questionnaire-Revised 2 (OR, 1.28; 95% CI, 1.11-1.47), and Revised Dyadic Adjustment Scale (OR, 1.32; 95% CI, 1.01-1.58) total sum scores were associated with child RRIs by the age of 24 months. Greater number of siblings, shorter duration of breastfeeding, and the level of maternal education were also identified as risk factors for child RRIs.

CONCLUSIONS

Maternal prenatal psychological distress is linked with a higher risk for child RRIs.

Passive smoking induces pediatric asthma by affecting the balance of Treg/Th17 cells

BACKGROUND

We aimed to explore the effects of passive smoking on the severity of pediatric asthma and associated molecular mechanisms.

METHODS

A total of 378 children with asthma were assigned into four groups according to asthma severity (from grades I to IV). Univariate and multivariate regression analyses were used to analyze possible factors associated with asthma severity in children. Environmental tobacco smoke (ETS) exposure was measured via cotinine concentration in urine. Serum levels of immunoglobulin E (IgE) and cytokines were measured using allergen diagnostic and ELISA (enzyme-linked immunosorbent assay) kits. The percentage of T-regulatory (Treg) and T-helper type 17 (Th17) cells in peripheral blood mononuclear cells (PMBCs) were measured by flow cytometry. Treg- and Th17-associated transcription factors from PMBCs were measured by using ELISA kits.

RESULTS

The levels of ETS and serum IgE, and the duration and amounts of passive smoking were closely associated with asthma severity. Passive smoking significantly reduced the levels of FoxP3 (Forkhead/winged helix transcription factor) and tumor growth factor-β, which were associated with Treg cells, and increased the levels of interleukin-17A and interleukin-23, which were associated with Th17 cells. Meanwhile, passive smoking significantly reduced the ratio of Treg/Th17 cells (P < 0.05).

CONCLUSIONS

Passive smoking was closely associated with the severity of childhood asthma by affecting the balance of Treg/Th17 cells.

Secondhand Smoke Induces Inflammation and Impairs Immunity to Respiratory Infections

Despite advocacy to reduce smoking-related diseases, >1 billion people worldwide continue to smoke. Smoking is immunosuppressive and an important etiological factor in the development of several human disorders including respiratory diseases like chronic obstructive pulmonary disease. However, there is a critical gap in the knowledge of the role of secondhand smoke (SHS) in inflammation and immunity. We therefore studied the influence of SHS on pulmonary inflammation and immune responses to respiratory infection by nontypeable Haemophilus influenzae (NTHI) recurrently found in chronic obstructive pulmonary disease patients. Chronic SHS-exposed mice were chronically infected with NTHI and pulmonary inflammation was evaluated by histology. Immune cell numbers and cytokines were measured by flow cytometry and ELISA, respectively. Chronic SHS exposure impaired NTHI P6 Ag-specific B and T cell responses following chronic NTHI infection as measured by ELISPOT assays, reduced the production of Abs in serum and bronchoalveolar lavage, and enhanced albumin leak into the bronchoalveolar lavage as determined by ELISA. Histopathological examination of lungs revealed lymphocytic accumulation surrounding airways and bronchovasculature following chronic SHS exposure and chronic infection. Chronic SHS exposure enhanced the levels of inflammatory cytokines IL-17A, IL-6, IL-1β, and TNF-α in the lungs, and impaired the generation of adaptive immunity following either chronic infection or P6 vaccination. Chronic SHS exposure diminished bacterial clearance from the lungs after acute NTHI challenge, whereas P6 vaccination improved clearance equivalent to the level seen in air-exposed, non-vaccinated mice. Our study provides unequivocal evidence that SHS exposure has long-term detrimental effects on the pulmonary inflammatory microenvironment and immunity to infection and vaccination.

Early-life Exposure to Widespread Environmental Toxicants and Health Risk: A Focus on the Immune and Respiratory Systems

Evidence has accumulated that exposure to widespread environmental toxicants, such as heavy metals, persistent organic pollutants, and tobacco smoke adversely affect fetal development and organ maturation, even after birth. The developing immune and respiratory systems are more sensitive to environmental toxicants due to their long-term physical development, starting from the early embryonic stage and persisting into early postnatal life, which requires complex signaling pathways that control proliferation and differentiation of highly heterogeneous cell types. In this review, we summarize the effect of early-life exposure to several widespread environmental toxicants on immune and lung development before and after birth, including the effects on immune cell counts, baseline characteristics of cell-mediated and humoral immunity, and alteration of lung structure and function in offspring. We also review evidence supporting the association between early-life exposure to environmental toxicants and risk for immune-related diseases and lung dysfunction in offspring in later life.

Understanding the Association of Human Rhinovirus with Asthma

Human rhinoviruses are ubiquitous seasonal pathogens. They have known associations with first onset of wheezing illnesses in children and with asthma exacerbations in patients of all ages. It is not yet certain whether human rhinoviruses play a direct role in the pathogenesis of asthma by activating deleterious inflammatory responses or if they only serve as a catalyst to accelerate the disease in genetically predisposed individuals. There have been previously demonstrated reductions in the development of the asthmatic phenotype with passive immunization against respiratory syncytial virus; however, in the case of rhinovirus, there are barriers to effective vaccine development, such as the lack of a common antigenic target due to alterations of surface markers among subtypes. It remains to be determined whether certain subtypes of human rhinovirus are more asthmagenic and therefore worthy of greater attention as vaccine candidates, but several studies have suggested that RV-C and certain RV-A strains may be more strongly linked with asthma.

Toward primary prevention of asthma. Reviewing the evidence for early-life respiratory viral infections as modifiable risk factors to prevent childhood asthma

A first step in primary disease prevention is identifying common, modifiable risk factors that contribute to a significant proportion of disease development. Infant respiratory viral infection and childhood asthma are the most common acute and chronic diseases of childhood, respectively. Common clinical features and links between these diseases have long been recognized, with early-life respiratory syncytial virus (RSV) and rhinovirus (RV) lower respiratory tract infections (LRTIs) being strongly associated with increased asthma risk. However, there has long been debate over the role of these respiratory viruses in asthma inception. In this article, we systematically review the evidence linking early-life RSV and RV LRTIs with asthma inception and whether they could therefore be targets for primary prevention efforts.

Nicotine exaggerates LPS-induced airway hyperreactivity via JNK-mediated up-regulation of Toll-like receptor 4

Tobacco smokers often display increased airway hyperreactivity (AHR) when faced with bacterial infections. The present study uses a murine organ-culture model to dissect the mechanisms involved in this exaggerated smooth muscle response. Nicotine simulates the effects of smoking, and LPS represents bacterial infection. Contractile responses of isolated murine tracheal segments were analyzed in myographs after organ culture with increasing concentrations of LPS and/or nicotine for 4 days with or without specific MAPK inhibitors. Nicotine's effect on the expression of cell surface Toll-like receptors (TLRs), MCP-1, COX-2, and TNF-α were examined by real-time PCR. Increased protein expression was verified by immunohistochemistry. LPS concentration-dependently increased contractile responses to bradykinin and des-Arg(9)-bradykinin. A combination of nicotine and low-dose LPS caused powerful synergistic contractions along with increased kinin receptor expression. Specific kinin B1 and B2 receptor inhibitors blocked this reaction. Nicotine increased mRNA and protein expression of TLR4 and -6 in the epithelium and smooth muscle layer, with MCP-1 and COX-2 mRNA increasing in parallel. Specific inhibition of JNK attenuated nicotine's effects. In conclusion, long-term exposure to nicotine up-regulated the expression of TLR4 and -6 via a JNK-related pathway, causing an exaggeration of the LPS-induced local airway inflammation and increased AHR. This might offer a mechanistic explanation to the increased AHR seen in tobacco smokers confronted with bacterial infections.

Triple tobacco screen: opportunity to help families become smokefree

BACKGROUND

American Academy of Pediatrics policy recommends that pediatricians document environmental tobacco smoke (ETS) exposure of a child at every visit. The extent to which pediatricians adhere to this policy, however, is unknown.

PURPOSE

The goal of the study was to examine the extent to which pediatricians screen parents for tobacco use and home- and car-related smoking rules. Further, the potential association between factors associated with pediatrician inquiry into parental tobacco use and rules is examined.

METHODS

Post-visit exit interviews were conducted in ten pediatric practices between June 2009 and March 2011 with parents whose children had been seen by a healthcare provider. Parents were considered to have been given the "triple tobacco screen" if they reported being asked by a pediatric healthcare provider about their smoking behavior, smokefree home rules, and smokefree car rules. Bivariate analysis and multivariable logistic regression was done to explore factors associated with parents being given any component of the triple tobacco screening. Data were analyzed between March 2012 and February 2013.

RESULTS

Of 9145 parents interviewed, 20% of the parents reported being asked at least one question from the triple tobacco screen, and only 9% reported being asked all three questions. Overall, 17% of parents reported being asked about their smoking status, 16% about smokefree home rules, and 11% about smokefree car rules. Few smoking parents (23%) and fewer nonsmoking parents (19%) were screened about their tobacco use and behavior.

CONCLUSIONS

Pediatricians infrequently addressed ETS exposure of children among parents who do and do not smoke. Substantial missed opportunities may exist to counsel smokers and reduce ETS exposure of children in the most common exposure locations-the home and car.

Pathways linking socioeconomic status and postpartum smoking relapse

BACKGROUND

Low socioeconomic status (SES) exacerbates the high rate of smoking relapse in women following childbirth.

PURPOSE

This study examined multiple models of potential mechanisms linking SES and postpartum smoking relapse among women who quit smoking due to pregnancy.

METHODS

Participants were 251 women enrolled in a randomized clinical trial of a new postpartum smoking relapse prevention intervention. Four models of the prepartum mechanisms linking SES and postpartum smoking relapse were evaluated using a latent variable modeling approach.

RESULTS

Each of the hypothesized models were a good fit for the data. As hypothesized, SES indirectly influenced postpartum smoking relapse through increased prepartum negative affect/stress, reduced sense of agency, and increased craving for cigarettes. However, the model that included craving as the sole final pathway between SES and relapse demonstrated superior fit when compared with all other models.

CONCLUSIONS

Findings have implications for future interventions that aim to reduce postpartum relapse.

Prenatal exposure to substance of abuse: a worldwide problem

Substance abuse during pregnancy is an important public health issue affecting the mother and the growing infant. Preterm labor, miscarriage, abruption and postpartum hemorrhage are obstetric complications which have been associated with women who are dependent on abused substances. Moreover, women are also at an increased risk of medical problems such as poor nutrition, anemia, urinary tract infections as well as sexually transmitted infections, hepatitis, HIV and problems related to infection. Intrauterine growth restriction, prematurity, stillbirth, neonatal abstinence syndrome, and Sudden Infant Death Syndrome represent only some of fetal effects. Later on, during childhood, it has been shown that in utero exposure to substances of abuse is associated with increased rates of respiratory infections, asthma, ear and sinus infections. Moreover, these children are more irritable, have difficulty focusing their attention, and have more behavioral problems. Therefore, the assessment of in utero exposure to abused substance is extremely necessary and is relevant for the care of the mother and the offspring. In this sense, several approaches are possible; however, recently the evaluation of in utero exposure to abused drugs has been achieved by testing biological specimens coming from fetus or newborn, pregnant or nursing mother, or from both the fetus and the mother. Maternal and neonatal biological materials reflect exposure in a specific time period and each of them has different advantages and disadvantages in terms of accuracy, time window of exposure and cost/benefit ratio. The methodology for identification and determination of abused substances in biological materials are of great importance. Consequently, sensitive and specific bioanalytical methods are necessary to accurately measure biomarkers. Different immunoassays methods are used as screening methods for drug testing in the above reported specimens, however, the results from immunoassays should be carefully interpreted and confirmed by a more specific and sensitive chromatographic methods such as GC-MS or LC-MS. The interest in the development and optimization of analytical techniques to detect abused substances in different specimens is explained by the several possibilities and information that they can provide.

Parents smoking in their cars with children present

OBJECTIVE

To determine prevalence and factors associated with strictly enforced smoke-free car policies among smoking parents.

METHODS

As part of a cluster, randomized controlled trial addressing parental smoking, exit interviews were conducted with parents whose children were seen in 10 control pediatric practices. Parents who smoked were asked about smoking behaviors in their car and receipt of smoke-free car advice at the visit. Parents were considered to have a "strictly enforced smoke-free car policy" if they reported having a smoke-free car policy and nobody had smoked in their car within the past 3 months.

RESULTS

Of 981 smoking parents, 817 (83%) had a car; of these, 795 parents answered questions about their car smoking policy. Of these 795 parents, 29% reported having a smoke-free car policy, and 24% had a strictly enforced smoke-free car policy. Of the 562 parents without a smoke-free car policy, 48% reported that smoking occurred with children present. Few parents who smoke (12%) were advised to have a smoke-free car. Multivariable logistic regression controlling for parent age, gender, education, and race showed that having a younger child and smoking ≤10 cigarettes per day were associated with having a strictly enforced smoke-free car policy.

CONCLUSIONS

The majority of smoking parents exposed their children to tobacco smoke in cars. Coupled with the finding of low rates of pediatricians addressing smoking in cars, this study highlights the need for improved pediatric interventions, public health campaigns, and policies regarding smoke-free car laws to protect children from tobacco smoke.

The prevalence and effects of environmental tobacco smoke exposure among inner-city children: lessons for pediatric residents

PURPOSE

To determine the prevalence of environmental tobacco smoke (ETS) exposure, to explore the relationship between ETS exposure and the use of health services, and to examine the degree to which pediatric residents document ETS exposure status and counsel parents.

METHOD

In 2006, the authors recruited dyads of children (0-12 years old) and their mothers from an inner-city pediatric group practice clinic. Mothers completed a survey, and the authors searched the children's medical charts. The authors compared ETS-exposed children with nonexposed children using chi-square, t test, and ANOVA analyses. They also ran logistic regression analyses to examine the relationship between the use of health services and selected child and maternal variables.

RESULTS

More than 60% (142/232) of children were exposed to ETS, and more than 69% (99/142) of those children had a mother who smoked. ETS exposure significantly predicted the overall number of sick visits, even after controlling for sociodemographic confounders (odds ratio = 7.44; 95% confidence internal = 1.21-44.55). About 80% (187/232) of mothers reported that their child's pediatrician had counseled them on the dangers of ETS exposure. Less than half (105/232) of the children's charts included their ETS exposure status.

CONCLUSIONS

Although pediatric residents often counsel parents on the dangers of ETS exposure, educators should teach residents to regard ETS exposure status as a fifth vital sign. By screening for and documenting ETS exposure status, residents can identify at-risk children and parents, who could benefit from counseling.

[The Fetal Tobacco Syndrome - A statement of the Austrian Societies for General- and Family Medicine (ÖGAM), Gynecology and Obstetrics (ÖGGG), Hygiene, Microbiology and Preventive Medicine (ÖGHMP), Pediatrics and Adolescence Medicine (ÖGKJ) as well as Pneumology (ÖGP)]

Over more than 50 years, the nocuous effects of smoking in pregnancy on the fetus are well known. In the first years of science the focus was primarily on restricted fetal growth while in more recent years over 10.000 studies investigated the incomparably big sum of detrimental effects for the unborn's health. In this statement we want to present the recent scientific findings on this topic. The statement is aimed to show all doctors who treat pregnant women the present situation and evidence. In the beginning we give a short overview about the epidemiological situation in Europe. Then we present step by step the health effects with regards to pathophysiology and clinics. Furthermore the reader will learn about possibilities for smoking cessation in pregnancy. The problem of passive-smoking in pregnancy will be dealt with in a separate chapter. At present there is strong evidence that pregnant smoking has a detrimental effect on birth-weight, placenta-associated disease, stillbirth, sudden infant death syndrome (SIDS), childhood overweight, clefts, lung function, asthma, cardiovascular diseases and mental developmental disorders. These factors can be summarized by the term Fetal Tobacco Syndrome. There is supply for more studies for less investigated health effects. Pregnancy is a chance to stop smoking as most women show a high motivation in this period. Hence doctors of all disciplines should inform pregnant women about the detrimental effects of smoking on their unborn child and show them possibilities for smoking cessation.

Selection of rhinovirus 1A variants adapted for growth in mouse lung epithelial cells

Rhinoviruses (RVs) are picornaviruses that are causative agents of the majority of upper respiratory tract infections, or "common colds," in humans. RVs infect both the upper and lower respiratory tract, and in addition to the common cold may also cause pneumonia, complications in patients with chronic lung diseases such as cystic fibrosis, and asthma exacerbations. Convenient animal models are not available to study the pathogenesis of rhinovirus-induced illness. Rhinovirus RV1A replicates poorly in mouse cells; variants with improved replication were selected by serial passage through mouse embryonic fibroblasts and mouse lung epithelial cells. Adaptation for improved growth in mouse cells was mediated by amino acid changes in the RV1a non-structural protein 3A. Mouse cell-adapted RV1A was capable of productively infecting mice in which the airway was subjected to chemical permeabilization. A mouse model for RV infection will permit studies of RV pathogenesis and may identify targets for therapeutic intervention.

Effect of smoke-free home and workplace policies on second-hand smoke exposure levels in children: an evidence summary

Second-hand smoke (SHS) is a major avoidable cause of developmental and respiratory disease and premature death among children worldwide. SHS is a ‘Class A’ carcinogen, and there is no safe level of SHS exposure. Almost 700 million children worldwide are exposed daily to SHS at home. This article reviews and summarizes evidence based on available studies that report on ‘voluntary’ home smoking restrictions and their effects on SHS exposure levels in children aged 0–17 years. All potentially relevant publications within a 10-year period (January 2000–April 2010) were identified (n = 19 full-text articles) through comprehensive database searches. In general, voluntary household smoking restrictions reported a significant reduction in childhood SHS exposure ranging between 20–50% reductions, using both self-reported and biological measures. Mandated comprehensive workplace and enclosed public smoke-free policies also suggested an apparent benefit in some specific pediatric health encounters, namely, decreased preterm birth risks and reduced emergency hospital visits owing to asthma.

Prenatal allergen and diesel exhaust exposure and their effects on allergy in adult offspring mice

Background

Multiple studies have suggested that prenatal exposure to either allergens or air pollution may increase the risk for the development of allergic immune responses in young offspring. However, the effects of prenatal environmental exposures on adult offspring have not been well-studied. We hypothesized that combined prenatal exposure to Aspergillus fumigatus (A. fumigatus) allergen and diesel exhaust particles will be associated with altered IgE production, airway inflammation, airway hyperreactivity (AHR), and airway remodeling of adult offspring.

Methods

Following sensitization via the airway route to A. fumigatus and mating, pregnant BALB/c mice were exposed to additional A. fumigatus and/or diesel exhaust particles. At age 9-10 weeks, their offspring were sensitized and challenged with A. fumigatus.

Results

We found that adult offspring from mice that were exposed to A. fumigatus or diesel exhaust particles during pregnancy experienced decreases in IgE production. Adult offspring of mice that were exposed to both A. fumigatus and diesel exhaust particles during pregnancy experienced decreases in airway eosinophilia.

Conclusion

These results suggest that, in this model, allergen and/or diesel administration during pregnancy may be associated with protection from developing systemic and airway allergic immune responses in the adult offspring.

[Perinatal exposure to tobacco and respiratory and allergy symptoms in first years of life]

BACKGROUND AND OBJECTIVES

To analyse the relationship between prenatal and postnatal tobacco exposure and the development of respiratory and allergy symptoms during the first 4 years of life.

PATIENTS AND METHODS

Prospective and multicentred cohort study that included the subjects belonging to AMICS (Asthma Multicentred Infant Cohort Study) located in Ashford (England), Barcelona and Minorca (Spain). We recruited 1611 children, followed from the pregnancy to the 4th year of life, whose parents annually answered a questionnaire on their tobacco consumption and their children's respiratory and allergy health. In the Barcelona cohort (n=487) a tobacco exposure biomarker (cotinine) was analysed on several matrices.

RESULTS

Prenatal tobacco exposure is associated with a greater risk of hospitalisation due to respiratory infection, particularly in the second year of life, whereas postnatal tobacco exposure is associated more strongly with the presence of late wheezing presence and increases in the chance of being diagnosed with asthma at 4 years of age. The children prenatally and postnatally exposed had more persistent wheezing, persistent rhoncus, early cough, a higher number of upper respiratory infections per year and a greater number were diagnosed with asthma. The higher the levels of cotinine measured, the higher was the risk for wheezing. No relationship was seen between tobacco exposure and atopic symptoms.

CONCLUSIONS

Passive smoke exposure during pregnancy and childhood has very distinct clinical respiratory effects in children. Therefore, smoking cessation of childbearing age women must be a priority of preventive medicine.

Is environmental tobacco smoke exposure a risk factor for acute gastroenteritis in young children?

Because passive smoke exposure has not been previously linked to diarrhea diseases in children, it was hypothesized that very young children exposed to environmental tobacco smoke (ETS) exposure at home would also be more likely to develop infectious gastroenteritis (GE) than their unexposed counterparts. During 1-year period, 260 children 36 months and younger were prospectively followed up in a private pediatric practice in a southern community in the United States. Multiple logistic regression analysis showed that ETS was strongly predictive of acute GE in the univariate analysis (P = .003). Even after controlling for the various confounders, ETS exposure was still significantly associated with acute GE (relative risk = 2.55; 95% CI = 1.26-5.18). It is speculated that, similar to acute respiratory infections, the same mechanisms may explain why ETS may also be associated with acute infectious GE.

Environmental tobacco smoke (ETS) and respiratory health in children

Environmental tobacco smoke (ETS) is a major risk factor for poor lung health in children. Although parental smoking is the commonest source of ETS exposure to children, they are also exposed to ETS in schools, restaurants, public places and public transport vehicles. Apart from containing thousands of chemicals, the particle size in the ETS is much smaller than the main stream smoke, and therefore has a greater penetrability in the airways of children. Exposure to ETS has been shown to be associated with increased prevalence of upper respiratory tract infections, wheeze, asthma and lower respiratory tract infections. Even developing fetuses are exposed to ETS via the umbilical cord blood if the mother is exposed to tobacco smoke. The placenta also does not offer any barrier to the penetration of ETS into the fetus. The immune system in these babies is more deviated toward the allergic and asthmatic inflammatory phenotype and therefore makes them more prone to develop asthma later in life. An increased awareness of the harmful effects of ETS on children's health is warranted.

Effects of early cigarette smoke exposure on early immune development and respiratory disease

Exposure to tobacco constituents during early development remains a common but avoidable toxic exposure, which has been clearly linked with decreased lung growth and subsequent wheezing illness. There is also now emerging evidence that tobacco smoke can influence early immune function. This includes alterations in cytokine production by the fetoplacental unit, as detected ex vivo in cord blood, as well as in patterns of fetal mononuclear cell responses in vitro. Recent studies also suggest that the newborns of smoking mothers have altered signalling through Toll-like receptors (TLRs) that are essential for innate microbial responses. This may be implicated in the increased predisposition to infection in exposed infants. TLR-mediated innate response pathways are also believed to be important in promoting regulatory pathways that inhibit allergic immune responses. However, although a number of studies have documented associations between early cigarette smoke exposure and subsequent allergic disease, this remains controversial. This review explores the consequences of smoking on these important aspects of early development, including potential mechanisms, interactions with predisposing asthma genes and a potential role in epigenetic regulation. Although parental smoking may not be the primary factor in the changing prevalence of asthma and respiratory disease, we propose that it is an important contributor, with significant potential to interact with other genetic factors and environmental risk factors to influence disease propensity.

Indoor air quality and the risk of lower respiratory tract infections in young Canadian Inuit children

BACKGROUND

Inuit infants have the highest reported rate of hospital admissions because of lower respiratory tract infections in the world. We evaluated the prevalence of reduced ventilation in houses in Nunavut, Canada, and whether this was associated with an increased risk of these infections among young Inuit children.

METHODS

We measured ventilation in 49 homes of Inuit children less than 5 years of age in Qikiqtaaluk (Baffin) Region, Nunavut. We identified the occurrence of lower respiratory tract infections using a standardized questionnaire. Associations between ventilation measures and lower respiratory tract infection were evaluated using multiple logistic regression models.

RESULTS

The mean number of occupants per house was 6.1 people. The mean ventilation rate per person was 5.6 L/s (standard deviation [SD] 3.7); 80% (37/46) of the houses had ventilation rates below the recommended rate of 7.5 L/s per person. The mean indoor carbon dioxide (CO2) concentration of 1358 (SD 531) ppm was higher than the recommended target level of 1000 ppm. Smokers were present in 46 homes (94%). Of the 49 children, 27 (55%) had a reported history of lower respiratory tract infection. Reported respiratory infection was significantly associated with mean CO2 levels (odds ratio [OR] 2.85 per 500-ppm increase in mean indoor CO2, 95% confidence interval [CI] 1.23-6.59) and occupancy (OR 1.81 for each additional occupant, 95% CI 1.14-2.86).

INTERPRETATION

Reduced ventilation and crowding may contribute to the observed excess of lower respiratory tract infection among young Inuit children. The benefits of measures to reduce indoor smoking and occupancy rates and to increase ventilation should be studied.

Parental smoking and children's respiratory health: independent effects of prenatal and postnatal exposure

OBJECTIVES

Adverse effects have been reported of prenatal and/or postnatal passive exposure to smoking on children's health. Uncertainties remain about the relative importance of smoking at different periods in the child's life. We investigate this in a pooled analysis, on 53,879 children from 12 cross-sectional studies--components of the PATY study (Pollution And The Young).

METHODS

Effects were estimated, within each study, of three exposures: mother smoked during pregnancy, parental smoking in the first two years, current parental smoking. Outcomes were: wheeze, asthma, "woken by wheeze", bronchitis, nocturnal cough, morning cough, "sensitivity to inhaled allergens" and hay fever. Logistic regressions were used, controlling for individual risk factors and study area. Heterogeneity between study-specific results, and mean effects (allowing for heterogeneity) were estimated using meta-analytical tools.

RESULTS

There was strong evidence linking parental smoking to wheeze, asthma, bronchitis and nocturnal cough, with mean odds ratios all around 1.15, with independent effects of prenatal and postnatal exposures for most associations.

CONCLUSIONS

Adverse effects of both pre- and postnatal parental smoking on children's respiratory health were confirmed. Asthma was most strongly associated with maternal smoking during pregnancy, but postnatal exposure showed independent associations with a range of other respiratory symptoms. All tobacco smoke exposure has serious consequences for children's respiratory health and needs to be reduced urgently.

Maternal smoking in pregnancy: do the effects on innate (toll-like receptor) function have implications for subsequent allergic disease?

Subtle increases in immaturity of immune function in early infancy have been implicated in the rising susceptibility to allergic disease, particularly relative impairment of type 1 interferon (IFN)-γ responses in the neonatal period. Although genetic predisposition is a clear risk factor, the escalating rates of allergic disease in infancy suggest that environmental factors are also implicated. We previously showed that maternal smoking in pregnancy may impair neonatal IFN-γ responses. Our more recent studies now indicate that this common avoidable toxic exposure is also associated with attenuation of innate immune function, with attenuated Toll-like receptor (TLR)-mediated microbial responses (including TLR-2, -3, -4, and -9 responses). Most notably, the effects were more marked if the mothers were also allergic. In this review, we discuss the significance of these observations in the context of the emerging hypothesis that variations in TLR function in early life may be implicated in allergic propensity. There is now growing evidence that many of the key pathways involved in subsequent T-cell programming and regulation (namely, antigen-presenting cells and regulatory T cells) rely heavily on microbe-driven TLR activation for maturation and function. Factors that influence the function and activity of these innate pathways in early life may contribute to the increasing predisposition for allergic disease. Although "cleaner" environments have been implicated, here we explore the possibility that other common environmental exposures (such as maternal smoking) could also play a role.

Association of maternal smoking with increased infant oxidative stress at 3 months of age

BACKGROUND

Cigarette smoke is a major source of free radicals and oxidative stress. With a significant proportion of women still smoking during pregnancy, this common and avoidable exposure has the potential to influence infant oxidative status, which is implicated in the increased propensity for airway inflammation and asthma. The aim of this study was to examine the effects of maternal smoking on markers of infant oxidative stress.

METHODS

The level of oxidative stress (using urinary F2-isoprostanes as a marker of lipid peroxidation) was compared in infants of smokers (n = 33) and non-smokers (n = 54) at 3 months of age. These groups were balanced for maternal atopy and socioeconomic status. Infant urinary cotinine levels were also measured as an indicator of early postnatal cigarette smoke exposure.

RESULTS

Maternal smoking was associated with significantly higher infant cotinine levels, despite the fact that most smoking mothers (83.8%) claimed not to smoke near their baby. Maternal smoking was associated with significantly higher markers of oxidative stress (F2-isoprostane) at 3 months of age. There was also a positive correlation between urinary F2-isoprostanes and infant urinary cotinine levels.

CONCLUSIONS

Although this study does not separate the prenatal and postnatal effects of smoking, these findings indicate that environmental tobacco smoke in the early postnatal period adversely affects pro-oxidative/antioxidative status within weeks of life in very early infancy.

The effects of maternal smoking on early mucosal immunity and sensitization at 12 months of age

With the dramatic rise in asthma and respiratory disease, there is an urgent need to determine the effects of common environmental exposures on early immune development. In this study, we examined the effects of maternal smoking as a major adverse exposure in early life, on mucosal immune function and allergen sensitization in the first year of life. A cohort of 60 smokers and 62 non-smokers was recruited in pregnancy, and followed prospectively at 3 and 12 months of age for saliva collection [for immunoglobulin (Ig) A measurements], urine collection (for cotinine levels) and clinical assessments (for allergy and infection history). Allergen skin-prick tests were also performed at 12 months of age. Specific IgA to common colonizing bacteria was measured on saliva samples, including pneumococcal polysaccharide (PS) serotype 14 and non-typeable Haemophilus influenza (NTHI) outer membrane protein 6 (OMP6). Eighty-two mothers and their infants completed the 12-month follow-up period--56 in the maternal non-smoking group and 26 in the maternal smoking group. Maternal smoking was associated with significantly higher total infant salivary IgA at 12 months of age (p = 0.026), and more chronic upper respiratory tract symptoms (p = 0.012). However, there were no differences in the level of specific IgA antibodies to common colonizing bacteria (pneumococcal PS serotype 14 and NTHI OMP6). In general, the IgA levels at 12 months were higher in children who had more chest infections in the first year (Kendall's tau b, 0.282; p = 0.003). There was also a trend of lower respiratory tract symptoms (wheeze) (p = 0.142) in infants of smokers. There were no effects of maternal smoking on the rates of allergen sensitization, atopic dermatitis and food allergy at 12 months of age. In conclusion, maternal smoking did not inhibit the production of anti-microbial IgA, suggesting that other factors are responsible for the increased susceptibility to infection in these infants. The increased mucosal inflammation in these children was not associated with effects on early allergy propensity.

Measuring air quality to protect children from secondhand smoke in cars

BACKGROUND

Secondhand tobacco smoke (SHS) is a major, preventable contributor to acute and chronic adverse health outcomes that affect children disproportionately. The predominant source of SHS among children is domestic exposure, and while up to two thirds of U.S. households have car smoking bans, an unacceptable number of children remain vulnerable. To help promote more effective protection through legislation, health communication strategies, or behavioral interventions, data demonstrating the adverse effect of SHS on air quality in cars are needed.

METHODS

Secondhand tobacco smoke in a motor vehicle under actual driving conditions was monitored by measuring respirable suspended particles (RSPs) of less than 2.5 microns in diameter, and carbon monoxide. Forty-five driving trials were conducted, using teams of volunteer drivers and smokers recruited from the general community. Three smoking conditions (nonsmoking baseline, active smoking, and immediate post-smoking period, each 5 minutes) were crossed with two ventilation conditions (windows open, closed) in a 3 x 2 within-sessions factorial design.

RESULTS

The highest mean observed RSP level was 271 mug/m(3), which is unsafe, particularly for children. Peak RSP levels were considerably higher. RSPs and carbon monoxide increased significantly from baseline after smoking, and these increases were greatest during the closed ventilation condition, compared with open ventilation.

CONCLUSIONS

Private passenger cars are a domestic environment with the potential to yield unsafe levels of SHS contaminants. These data may assist policymakers and health advocates to promote protective strategies to ensure smoke-free domestic environments for children.

The effects of smoking cessation counseling by midwives on Dutch pregnant women and their partners

OBJECTIVE

Smoking during pregnancy is an important problem in the Netherlands. We tested the effectiveness of a health counseling method by midwives using a RCT.

METHODS

Four provinces with 42 practices including 118 midwives were randomly assigned to the experimental or control condition. Midwives in the experimental group provided brief health counseling, self-help materials on smoking cessation during pregnancy and early postpartum, and a partner booklet. Controls received routine care. The main outcome measures were 7-day abstinence, continuous abstinence, and partner smoking at 6 weeks post-intervention (T1) and 6 weeks postpartum (T2).

RESULTS

Multi-level analysis revealed significant differences between both conditions at T1 and T2 using intention-to-treat analysis. Nineteen percent of the experimental group reported 7-day abstinence compared to 7% of the control group at T1, and 21 and 12%, respectively, at T2. For continuous abstinence these percentages were 12% in the experimental group and 3% in the control group. The partner intervention was not successful.

CONCLUSION

The intervention resulted in significant effects on smoking behavior for pregnant women, but not for partner smoking.

PRACTICE IMPLICATIONS

The program realized short-term effects. An important precondition is that midwives need a proper training.

Environmental tobacco smoke exposure: prevalence and mechanisms of causation of infections in children

BACKGROUND AND OBJECTIVES

Environmental tobacco smoke (ETS) exposure is probably one of the most important public health hazards in our community. Our aim with this article is to (1) review the prevalence of ETS exposure in the United States and how this prevalence is often measured in practice and (2) summarize current thinking concerning the mechanism by which this exposure may cause infections in young children.

METHODS

We conducted a Medline search to obtain data published mainly in peer-reviewed journals.

RESULTS

There is still a very high prevalence of ETS exposure among US children ranging from 35% to 80% depending on the method of measurement used and the population studied. The mechanism by which ETS may be related to these infections is not entirely clear but may be through suppression or modulation of the immune system, enhancement of bacterial adherence factors, or impairment of the mucociliary apparatus of the respiratory tract, or possibly through enhancement of toxicity of low levels of certain toxins that are not easily detected by conventional means.

CONCLUSIONS

The prevalence of ETS exposure in the United States is still very high, and its role in causing infections in children is no longer in doubt even if still poorly understood. Research, therefore, should continue to focus on the various mechanisms of causation of these infections and how to best reduce the exposure levels.

Fetal and postnatal exposure to tobacco smoke and respiratory health in children

The aim of this paper was to find out whether fetal exposure to environmental tobacco smoke (ETS), as compared to postnatal ETS exposure, is an independent risk factor for respiratory symptoms and diseases in younger schoolchildren. The cross-sectional epidemiological study comprised population of 1,561 Polish schoolchildren, aged 9-11 years. Information on the exposure to tobacco smoke and other sources of indoor air pollution at home, respiratory and allergic health status, and socio-economic status of the family was obtained by questionnaire survey. The respiratory health status was described by presence of wheezing, attacks of dyspnoea (noted during the last year or ever), bronchitis, wheezy bronchitis and asthma, ever diagnosed by a physician. Multivariate logistic regression analysis with adjustment for age, sex, area of residence, household density, damp and mould stains found at home, use of coal-fired stove, co-habitant pets, mother's education and paternal current and past smoking habit was used to assess the effect of fetal and postnatal exposures on respiratory health outcomes. The results of the multivariate analyses revealed statistically significant associations between fetal exposure to ETS and wheezing ever: log OR = 1.4 (95% CI: 1.0-2.0), attacks of dyspnoea ever: log OR = 1.8 (95% CI: 1.1-2.9), bronchitis: log OR = 2.1 (95% CI: 1.5-2.9), and wheezy bronchitis: log OR = 1.8 (95% CI: 1.1-2.9). The effect of postnatal ETS was statistically significant only for bronchitis: log OR = 1.4 (95% CI: 1.1-1.9). The results of our study showed that fetal exposure to tobacco smoke is an independent risk factor for symptoms of wheeze and wheezy bronchitis in schoolchildren when compared to postnatal ETS exposure.

Air quality, tobacco smoke, urban crowding and day care: modern menaces and their effects on health

BACKGROUND

The known adverse health effects of outdoor air pollution were reduced in the last century by effective legislation and pollution control. Although combustion of biomass fuels in the indoor environment remains a major hazard in developing countries, there has been a change in the nature of the traffic-generated air pollutants in outdoor air in developed countries. The role of day care and siblings in increasing the risk of infection early in life contrasts with protection from allergic disease later.

METHODS

The mechanisms of how these pollutants exert their effects are poorly understood, but there is emerging evidence that the toxic effects may be related to infection. This synopsis discusses the epidemiologic relationship of the menaces of modern living, including air pollution, urban crowding and infection, and will explore some of the mechanisms of how they act synergistically to cause exacerbations of illnesses in individuals with preexisting respiratory conditions, such as asthma. It will also discuss the roles of day care and siblings in relation to respiratory disease risk.

RESULTS

Current evidence suggests that much of the morbidity and mortality related to sources of both indoor and outdoor pollution occur by causing or interacting with respiratory infection and other acute or chronic health conditions, such as asthma.

CONCLUSION

Improvements in air quality through efforts to tackle environmental problems such as pollution and tobacco smoke will help achieve better health. Day care and siblings increase infectious disease early in life but are associated with protection against development of allergic disease later.

Prenatal alcohol and drug exposures in adoption

Prenatal alcohol and drug exposures are a significant concern in many domestic and international adoptions. This article addresses the following substance exposures for children: alcohol, opiates, tobacco, marijuana, cocaine, and methamphetamines. For each substance, we review the teratogenicity of the exposure and identify the spectrum of neurodevelopmental issues that can present in children exposed to this substance. Diagnosis of the spectrum of fetal alcohol outcomes is also discussed. When possible, we provide country-specific statistics on exposure risks for adopted children.

TNF-308 modifies the effect of second-hand smoke on respiratory illness-related school absences

RATIONALE

Exposure to second-hand smoke (SHS) has been associated with increased risk of respiratory illness in children including respiratory illness-related school absences. The role of genetic susceptibility in risk for adverse effects from SHS has not been extensively investigated in children.

OBJECTIVE

To determine whether the tumor necrosis factor (TNF) G-308A genotype influences the risk for respiratory illness-related school absences associated with SHS exposure.

METHODS

Incident school absences were collected, using an active surveillance system, between January and June 1996, as part of the Air Pollution and Absence Study, a prospective cohort study nested in the Children's Health Study. Buccal cells and absence reports were collected on 1,351 students from 27 elementary schools in California.

MEASUREMENTS AND MAIN RESULTS

Illness-related school absences were classified as nonrespiratory and respiratory illness-related, which were further categorized into upper or lower respiratory illness-related absences based on symptoms. The effect of SHS exposure on respiratory illness-related absences differed by TNF genotype (p interaction, 0.02). In children possessing at least one copy of the TNF-308 A variant, exposure to two or more household smokers was associated with a twofold risk of a school absence due to respiratory illness (relative risk, 2.13; 95% confidence interval, 1.34, 3.40) and a fourfold risk of lower respiratory illness-related school absence (relative risk, 4.15; 95% confidence interval, 2.57, 6.71) compared with unexposed children homozygous for the common TNF-308 G allele.

CONCLUSIONS

These results indicate that a subgroup of genetically susceptible children are at substantially greater risk of respiratory illness if exposed to SHS.

Treating nicotine dependence during pregnancy and postpartum: understanding clinician knowledge and performance

This study investigated the relationship of clinicians' knowledge of treatments for nicotine dependence during pregnancy and postpartum and explored what provider characteristics are associated with knowledge levels. Survey data from community health center (CHC)-based prenatal, pediatric (PED), and WIC program (Special Supplemental Nutrition Program for Women, Infants, and Children) providers participating in a randomized clinical study were used. Providers reported low awareness of the health risks of smoking to the developing fetus/child of pregnant and postpartum women and of the effectiveness of nicotine replacement therapy (NRT) for doubling quit rates. Obstetric (OB) and WIC providers were more aware than PED providers that provider-delivered interventions are effective. Confidence in using counseling steps was significantly associated with general and NRT-related knowledge. NRT-related knowledge, but not general knowledge, was associated with higher performance of intervention steps. Educational programs targeting OB, WIC, and PED providers' knowledge about effective smoking cessation counseling strategies and their confidence in being effective with patients are needed.

Spontaneous cessation of smoking and alcohol use among low-income pregnant women

BACKGROUND

Despite the strong evidence of harmful effects, tobacco and alcohol use during pregnancy continue to be major public health challenges. Some women, however, do stop spontaneously when they learn of their pregnancy. No study has investigated spontaneous cessation of both behaviors in a low-income predominantly unmarried U.S. population.

OBJECTIVE

To describe the prevalence of spontaneous cessation of cigarette and alcohol use alone and in combination and associated factors among low-income pregnant women.

METHODS

Subjects (N=601) were currently smoking or smoking when they became pregnant and participating in Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) programs in the greater Boston, Massachusetts, area. Baseline interviews assessed the factors being studied and the spontaneous cessation of cigarette and alcohol use with pregnancy. Saliva cotinine verified self-reported smoking status.

RESULTS

Spontaneous cessation of smoking and alcohol use was reported by 28% and 80% of the women, respectively; 25% spontaneously quit both, and 15% stopped neither. Multivariable analyses indicated that smoking cessation was less likely in women who had previous births, had a husband or partner who smoked, were born in the United States, were black (non-Hispanic, non-Portuguese), had less than a high school education, were highly addicted, reported lower perceived risk to the fetus, and reported "too many other problems in life to stop." Hispanic ethnicity, younger age, and more social support to quit smoking were related to spontaneous alcohol abstinence.

CONCLUSIONS

Targeted multiple strategies, including those aimed at increasing participation of partners, are needed for low-income pregnant smokers.

Cigarette smoke-induced airway hyperresponsiveness is not dependent on elevated immunoglobulin and eosinophilic inflammation in a mouse model of allergic airway disease

Epidemiologic studies suggest that children raised in homes of cigarette smokers have a higher incidence of asthma than children who are raised in homes of nonsmokers. We sought to develop an experimental model to understand the mechanisms involved. Female BALB/c mice were paired with male DO11.10 ovalbumin (OVA)-T cell receptor hemizygous (+/-) mice such that the offspring were either transgene positive (+/-) or negative (-/-). Mice were exposed to either air or mainstream cigarette smoke (100 mg/m(3) total particulate matter, 6 hours/day, 7 days/week) during pregnancy. Immediately after birth, newborn mice were exposed for 4 weeks to either air or sidestream cigarette smoke (SS; 5 mg/m(3) total particulate matter, 6 hours/day, 5 days/week) and then exposed for the following 6 weeks to either air, SS, OVA (5 mg/m(3), 6 hours/day, 5 days/week) or a combination of OVA-SS. DO11.10 +/- offspring exposed to OVA had increased airway hyperresponsiveness (AHR) to methacholine challenge, total IgE, OVA-specific IgE and IgG(1), lymphocytes, and neutrophils in bronchoalveolar lavage and perivascular and peribronchiolar inflammation. Exposure to SS alone caused a significant increase in AHR in both +/- and -/- mice. Transgene -/- mice did not exhibit AHR after OVA exposure unless it was delivered in combination with SS. When compared with OVA-only exposure, OVA-SS exposure decreased total IgE, OVA-specific IgE, and IgG(1) amounts in +/- mice. These results indicate that exposure to SS after birth enhanced AHR in offspring that are both predisposed (+/-) and nonpredisposed (-/-) to develop an allergic response to OVA, but this AHR was not associated with elevated lung eosinophilia or OVA-specific Ig amounts.

Parental smoking and respiratory tract infections in children

The adverse health consequences of exposing children to tobacco smoke have been well documented. Re-calculation of the data available from cohort and cross-sectional studies worldwide shows that between 500-2500 excess hospitalisations and between 1000 to 5000 excess diagnoses per 100 000 young children as result from respiratory infections can be directly attributed to parental smoking. Results of published meta-analyses support these figures, which are probably under-estimated because of the effects of non-differential misclassification bias. These excess infections are a source of preventable morbidity and have a high cost to the community. They also have important long-term consequences because children who have respiratory infections in early life are at an increased risk of developing asthma in later childhood. More effective strategies that prevent smoking in young people before they become parents have the potential to lead to reductions in these high rates of unnecessary morbidity in the next generation of children.

Selected secondhand smoke research: summary and comment

Secondhand smoke is one of the more controversial public health issues. It is controversial because laws regulating secondhand smoke create conflict between the rights of smokers and non-smokers. The results of secondhand smoke research frequently focus on risk factors in four areas: heart disease, cancer, respiratory disorders, and middle ear discase. While many studies have found hazards in each of these four areas, there is some disagreement regarding the degree and extent of the threat posed by these hazards. Future research should discover more risks associated with secondhand smoke and suggest appropriate educational, medical, legal, and environmental remedies for this problem. Then society can establish prevention programs and enact laws which protect non-smokers, but at the same time infringe as little as possible on the rights of others.

Epidemiologic basis for an occupational and environmental policy on environmental tobacco smoke

ETS contains numerous toxins. Robust epidemiologic evidence implicates ETS as a cause of lung cancer and as a primary cause and source of exacerbation of excess respiratory disease. There is also increasing evidence that ETS may be associated with other outcomes, including heart disease. There is currently little doubt that ETS is an important and avoidable health hazard. Unfortunately, ETS is frequently encountered in the workplace--where it is no safer than in other environments and where it presents hazards to exposed workers and to others. A unique aspect of workplace ETS is that exposure is rarely an outcome of essential manufacturing, extraction, or service delivery processes. Moreover, ETS exposure, with its growing list of known hazards, is preventable by engineering or policy means. Implementation of policies to prevent workplace ETS can be highly effective while entailing low costs and yielding primary and secondary benefits to employers and employees. ACOEM strongly supports an increase in the scope and effectiveness of policies and efforts that protect against exposure to ETS in the workplace and elsewhere. To that end, ACOEM supports voluntary, regulatory, and legislative initiatives to eliminate ETS from the workplace, including public spaces such as bars, casinos, restaurants, schools, day-care centers, and public transportation. ACOEM also encourages employers to provide employee training concerning the health hazards of ETS and voluntary personal smoking-cessation programs.

Smoking cessation counseling with pregnant and postpartum women: a survey of community health center providers

OBJECTIVES

This study assessed providers' performance of smoking cessation counseling steps with low-income pregnant and postpartum women receiving care at community health centers.

METHODS

WIC (Special Supplemental Nutrition Program for Women, Infants, and Children) program staff, obstetric clinicians, and pediatric clinicians at 6 community health centers were asked to complete surveys. Smoking intervention practices (performance), knowledge and attitudes, and organizational facilitators were measured. Factors associated with performance were explored with analysis of variance and regression analysis.

RESULTS

Performance scores differed significantly by clinic and provider type. Providers in obstetric clinics had the highest scores and those in pediatric clinics had the lowest scores. Nurse practitioners and nutritionists had higher scores than other providers. Clinic type, greater smoking-related knowledge, older age, and perception of smoking cessation as a priority were independently related to better counseling performance.

CONCLUSIONS

Mean performance scores demonstrated room for improvement in all groups. Low scores for performance of steps beyond assessment and advice indicate a need for emphasis on the assistance and follow-up steps of national guidelines. Providers' own commitment to helping mothers stop smoking was important.

Epidemiology of respiratory infectious diseases

Respiratory infections are a frequent burden to health despite the fact that cost-effective methods for their prevention and cure are available. Acute respiratory infections in children under 5 years of age are the most frequent cause of death from lung disease globally, causing more than 4 million deaths annually. Tuberculosis is the most frequent cause of death from a single pathogen in persons aged 15 to 49 years (a total of 2 million to 3 million deaths annually). Respiratory infections are the most frequent complications of immune deficiency (whether due to HIV infection or induced by chemotherapy). Where a "carrier state" occurs (as with many bacterial pathogens), the level of immune function is the key determinant in appearance of disease. Where there is no carrier state (as with many viruses), exposure is the key determinant. Characteristics of the pathogen, including virulence and bacterial load where there is a carrier state, also determine the probability of respiratory infections. Modifiers of these determinants include allergy and toxic exposures including tobacco smoke and ambient pollution.