What determines levels of passive smoking in children with asthma?

İdrar kotinin ve kotinin/kreatinin oranının çevresel tütün dumanı maruziyetinin bir biyolojik belirteci olarak kullanımı

Purpose: Exposure to Environmental Tobacco Smoke (ETS) remains a worldwide public health problem. The purpose of this study was to investigate the relationship between parents' smoking habits at home and children's exposure to environmental tobacco smoke by measuring urinary cotinine levels and urine cotinine/creatinine ratios in children. Materials and Methods: This case-control typed analytical study was conducted with 357 children in the 0-18 age group. The case group consisted of 180 children exposed to environmental cigarette smoke. As the control group, it consisted of 177 healthy children and non-smoking in their family. The levels of cotinine and creatinine in spot urinary were analyzed in both groups. Results: The urinary cotinine level of the children was found to be statistically higher in those whose parents were smokers, female gender, fathers with a low educational level, and those with 3 or fewer rooms in the house. The urinary cotinine/creatinine ratio of the children was found to be statistically higher in those whose parents were smokers (15.91 pg/mg (1.54-147.54) vs 7.90 pg/mg (1.29-68.52)), female gender (13.19 pg/mg (1.79-115.07) vs 10.45 pg/mg (1.29-147.54)). Urinary cotinine levels in the ETS exposed group were affected 1042 times more than in the ETS unexposed group [OR:1042,462, 95% CI (139.821.839-7772.246)]. Conclusion: In the present study, urinary cotinine levels were found to be higher in children exposed to tobacco smoke than in children not exposed to tobacco smoke. In the light of these results, urinary cotinine can be used as a biomarker to evaluate exposure to ETS in children. Educating parents is essential to raising their awareness of exposure to ETS and teaching the right behaviors to protect children's health, especially in the home environment.

Effects of second-hand smoking on lung functions in athlete and non-athlete school-aged children - observational study

Background

Second-hand smoking or environmental tobacco smoke is a critical health risk. Children are the most vulnerable to second-hand smoking because of their small bronchial ducts, less developed immunity, and low-physical activity.

Objectives

The purpose of this study was to ascertain the effects of second-hand smoking on lung functions in athlete and non-athlete school-aged children.

Methods

This observational study included forty-six school-aged children, their age was 8–15 years, assigned to three groups; 2 study groups and 1 control group (n=15). The study groups comprised of 16 football players, and of 15 cyclists. Lung functions were evaluated recording forced vital capacity, forced expiratory volume in 1 sec and peak expiratory flow using digital spirometer.

Results

All measures were recorded in definite values and the children were also classified into second-hand smoking (SH), or non-exposed to tobacco smoking (NE). The findings presented a significant increase (p<0.05) of the study groups in forced vital capacity, forced expiratory volume in 1 sec and peak expiratory flow solely for the non-exposed children. However, there were non-significant differences between the cyclists and football players or between the passive smoking children and non-exposed children in any of the two study groups (p>0.05).

Conclusion

The outcomes of this study suggest beneficial influences of the sports activity on the lung functions, without different influences of the cyclists and football players on the lung functions.

Exposure to environmental tobacco smoke by healthy children aged below five (Preliminary study)

AIM

Children are commonly affected by environmental tobacco smoke. The presence of exposure can be deduced from urinary urine kotinine/creatinine ratio and history. The aim of this study was to investigate passive smoking in healthy children between one-month and five year old, and to determine the adverse effects of passive smoking on child health.

MATERIAL AND METHODS

Children between one-month and five year old who were regularly monitored for health were included following informed consent given by their parents. The questionnaire method was used. Demographic variables, respiratory tract infections, recurrent infections were questioned. The levels of cotinine, creatinine were measured and the cotinine/creatinine ratios were calculated in urine specimens taken from the children. Growth status and infection frequency were determined using demographic data, cotinine/creatinine ratios in urine, exposure rate to second-hand tobacco smoke of the children.

RESULTS

The ratio of household smokers was 70.3%, the ratio of non-smokers was 29.7%. Fifty percent of the mothers were smokers. Urinary cotinine/creatinine ratios were found to be significantly higher in children of smokers compared with children of non-smokers (p=0.011). One third of the children was evaluated as passive smokers. The presence of a smoker at home and the increase in the number of cigarettes smoked during the day increased the frequency of acute respiratory infections (p=0.047).

CONCLUSION

In these regularly-monitored preschool children, we found frequent exposure to cigarette smoke. This study contributes to national data and will aid in increasing the awareness for the deleterious effects of passive smoking on child health.

Family and carer smoking control programmes for reducing children's exposure to environmental tobacco smoke

BACKGROUND

Children's exposure to other people's tobacco smoke (environmental tobacco smoke, or ETS) is associated with a range of adverse health outcomes for children. Parental smoking is a common source of children's exposure to ETS. Older children in child care or educational settings are also at risk of exposure to ETS. Preventing exposure to ETS during infancy and childhood has significant potential to improve children's health worldwide.

OBJECTIVES

To determine the effectiveness of interventions designed to reduce exposure of children to environmental tobacco smoke, or ETS.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group Specialised Register and conducted additional searches of the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PsycINFO, Embase, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), the Education Resource Information Center (ERIC), and the Social Science Citation Index & Science Citation Index (Web of Knowledge). We conducted the most recent search in February 2017.

SELECTION CRITERIA

We included controlled trials, with or without random allocation, that enrolled participants (parents and other family members, child care workers, and teachers) involved in the care and education of infants and young children (from birth to 12 years of age). All mechanisms for reducing children's ETS exposure were eligible, including smoking prevention, cessation, and control programmes. These include health promotion, social-behavioural therapies, technology, education, and clinical interventions.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies and extracted data. Due to heterogeneity of methods and outcome measures, we did not pool results but instead synthesised study findings narratively.

MAIN RESULTS

Seventy-eight studies met the inclusion criteria, and we assessed all evidence to be of low or very low quality based on GRADE assessment. We judged nine studies to be at low risk of bias, 35 to have unclear overall risk of bias, and 34 to have high risk of bias. Twenty-one interventions targeted populations or community settings, 27 studies were conducted in the well-child healthcare setting and 26 in the ill-child healthcare setting. Two further studies conducted in paediatric clinics did not make clear whether visits were made to well- or ill-children, and another included visits to both well- and ill-children. Forty-five studies were reported from North America, 22 from other high-income countries, and 11 from low- or middle-income countries. Only 26 of the 78 studies reported a beneficial intervention effect for reduction of child ETS exposure, 24 of which were statistically significant. Of these 24 studies, 13 used objective measures of children's ETS exposure. We were unable to pinpoint what made these programmes effective. Studies showing a significant effect used a range of interventions: nine used in-person counselling or motivational interviewing; another study used telephone counselling, and one used a combination of in-person and telephone counselling; three used multi-component counselling-based interventions; two used multi-component education-based interventions; one used a school-based strategy; four used educational interventions, including one that used picture books; one used a smoking cessation intervention; one used a brief intervention; and another did not describe the intervention. Of the 52 studies that did not show a significant reduction in child ETS exposure, 19 used more intensive counselling approaches, including motivational interviewing, education, coaching, and smoking cessation brief advice. Other interventions consisted of brief advice or counselling (10 studies), feedback of a biological measure of children's ETS exposure (six studies), nicotine replacement therapy (two studies), feedback of maternal cotinine (one study), computerised risk assessment (one study), telephone smoking cessation support (two studies), educational home visits (eight studies), group sessions (one study), educational materials (three studies), and school-based policy and health promotion (one study). Some studies employed more than one intervention. 35 of the 78 studies reported a reduction in ETS exposure for children, irrespective of assignment to intervention and comparison groups. One study did not aim to reduce children's tobacco smoke exposure but rather sought to reduce symptoms of asthma, and found a significant reduction in symptoms among the group exposed to motivational interviewing. We found little evidence of difference in effectiveness of interventions between the well infant, child respiratory illness, and other child illness settings as contexts for parental smoking cessation interventions.

AUTHORS' CONCLUSIONS

A minority of interventions have been shown to reduce children's exposure to environmental tobacco smoke and improve children's health, but the features that differentiate the effective interventions from those without clear evidence of effectiveness remain unclear. The evidence was judged to be of low or very low quality, as many of the trials are at a high risk of bias, are small and inadequately powered, with heterogeneous interventions and populations.

Does raising awareness in families reduce environmental tobacco smoke exposure in wheezy children?

Introduction

Environmental tobacco smoke (ETS) is thought to increase the severity and number of attacks in wheezy children. Objective assessments are needed to change the behavior of families to reduce the exposure of wheezy children to ETS.

Aim

To determine whether informing families about their children’s urinary cotinine levels curtailed the exposure of children to ETS.

Material and methods

A survey was used to determine the ETS exposure level, and the urinary cotinine level of each patient was tested. Children with positive urinary cotinine levels were included in the second part of the study. The families were randomly divided into two groups: an intervention group that was advised about urinary cotinine levels by telephone and a non-intervention group that was not so advised. The groups were followed-up 2 months later, and urinary cotinine levels were measured once again.

Results

The intervention group contained 65 children of average age of 24.4 ±8.9 months, of whom 46 (70.8%) were male. The non-intervention group contained 69 children of average age of 25.3 ±9.8 months (p > 0.05), of whom 52 (75.4%) were male. The urinary cotinine levels at the time of the second interview were lower in both groups. The number of cigarettes that fathers smoked at home decreased in the intervention group (p = 0.037).

Conclusions

Presenting objective evidence on ETS exposure to families draws attention to their smoking habits. Measurement of cotinine levels is cheap, practical, and noninvasive. Combined with education, creating awareness by measuring cotinine levels may be beneficial.

Cardiovascular Consequences of Childhood Secondhand Tobacco Smoke Exposure: Prevailing Evidence, Burden, and Racial and Socioeconomic Disparities: A Scientific Statement From the American Heart Association

BACKGROUND

Although public health programs have led to a substantial decrease in the prevalence of tobacco smoking, the adverse health effects of tobacco smoke exposure are by no means a thing of the past. In the United States, 4 of 10 school-aged children and 1 of 3 adolescents are involuntarily exposed to secondhand tobacco smoke (SHS), with children of minority ethnic backgrounds and those living in low-socioeconomic-status households being disproportionately affected (68% and 43%, respectively). Children are particularly vulnerable, with little control over home and social environment, and lack the understanding, agency, and ability to avoid SHS exposure on their own volition; they also have physiological or behavioral characteristics that render them especially susceptible to effects of SHS. Side-stream smoke (the smoke emanating from the burning end of the cigarette), a major component of SHS, contains a higher concentration of some toxins than mainstream smoke (inhaled by the smoker directly), making SHS potentially as dangerous as or even more dangerous than direct smoking. Compelling animal and human evidence shows that SHS exposure during childhood is detrimental to arterial function and structure, resulting in premature atherosclerosis and its cardiovascular consequences. Childhood SHS exposure is also related to impaired cardiac autonomic function and changes in heart rate variability. In addition, childhood SHS exposure is associated with clustering of cardiometabolic risk factors such as obesity, dyslipidemia, and insulin resistance. Individualized interventions to reduce childhood exposure to SHS are shown to be at least modestly effective, as are broader-based policy initiatives such as community smoking bans and increased taxation.

PURPOSE

The purpose of this statement is to summarize the available evidence on the cardiovascular health consequences of childhood SHS exposure; this will support ongoing efforts to further reduce and eliminate SHS exposure in this vulnerable population. This statement reviews relevant data from epidemiological studies, laboratory-based experiments, and controlled behavioral trials concerning SHS and cardiovascular disease risk in children. Information on the effects of SHS exposure on the cardiovascular system in animal and pediatric studies, including vascular disruption and platelet activation, oxidation and inflammation, endothelial dysfunction, increased vascular stiffness, changes in vascular structure, and autonomic dysfunction, is examined.

CONCLUSIONS

The epidemiological, observational, and experimental evidence accumulated to date demonstrates the detrimental cardiovascular consequences of SHS exposure in children.

IMPLICATIONS

Increased awareness of the adverse, lifetime cardiovascular consequences of childhood SHS may facilitate the development of innovative individual, family-centered, and community health interventions to reduce and ideally eliminate SHS exposure in the vulnerable pediatric population. This evidence calls for a robust public health policy that embraces zero tolerance of childhood SHS exposure.

Cost Analysis of Motivational Interviewing and Preschool Education for Secondhand Smoke Exposures

INTRODUCTION

This study determines if expenditures associated with implementing a combined motivational interviewing (MI) and Head Start-level education program (MI+Education), as compared to education alone, yield cost savings to society.

METHODS

Post hoc cost analyses were applied to a randomized controlled-trial of MI among predominantly African American, low-income caregivers of 330 Baltimore City Head Start students who reside with a smoker. The primary outcome was the cost savings of MI+Education from averted direct secondhand smoke exposure (SHSe)-related acute healthcare events and inferred indirect costs (work days lost, transportation and reduction in cigarettes smoked). The net direction of savings was defined by the sum of averted direct and indirect costs of the MI+Education intervention at 3, 6 and 12 months, benchmarked against the Education alone cohort at the equivalent time periods.

RESULTS

The costs saved by the MI+Education intervention, relative to Education alone, resulted in savings at solely the 12-month follow-up time point. Significant savings were appreciated from averted emergency department (ED) visits at 12 months ($4410; 95% simulation interval [SI]: $2241, $6626) for the MI+Education group. The total savings at 12 months ($2274; 95% SI: -3916, $8442) could not overcome additional program costs of implementing MI to Head Start-level education ($13 695; 95% SI: $11 250, $16 034).

CONCLUSIONS

This study is the first to examine the cost of either intervention on SHSe-attributed pediatric healthcare costs from a population level relevant for federal and community decision makers. Intervention costs could not be offset by short-term savings but a trend towards positive savings was appreciated 1 year after implementation.

IMPLICATIONS

Behavioral interventions are effective in reducing SHSe in children. However, many of these interventions are not implemented in community settings due to lack of resources and money. Behavioral strategies may be a cost-saving addition to the national initiatives to create smoke-free home environments. The long-term benefits of MI, as evidenced from cost savings from averted ED visits, appeared to show MI+Education to be a robust long-term strategy. The decrease of acute healthcare services at 12 months may be informative for policy decision makers seeking to allocate limited resources to reduce the usage of costly ED services and hospital readmissions.

Assessment of tobacco smoke exposure in the pediatric emergency department

OBJECTIVE

Tobacco smoke exposure causes significant childhood morbidity and is associated with a multitude of conditions. National organizations recommend tobacco smoke exposure screening at all pediatric clinical encounters. Data regarding tobacco smoke exposure screening in the pediatric emergency department is sparse, although children with tobacco smoke exposure-associated conditions commonly present to this setting. We aimed to determine the frequency and outcome of tobacco smoke exposure screening in the pediatric emergency department, and assess associated sociodemographic/clinical characteristics.

METHODS

This retrospective review included pediatric patients presenting to a large pediatric emergency department in Cincinnati, Ohio between 2012 and 2013. Variables extracted included: age, sex, race/ethnicity, insurance, child's tobacco smoke exposure status, triage acuity, diagnosis, and disposition. Regression analyses examined predictors of tobacco smoke exposure screening and tobacco smoke exposure status.

RESULTS

A total of 116,084 children were included in the analysis. Mean child age was 6.20years (SD±5.6); 52% were male. Nearly half of the children in the study did not undergo tobacco smoke screening; only 60% of children with tobacco smoke exposure-related illnesses were screened. Predictors of tobacco smoke exposure screening were: younger age, male, African American, non-commercial insurance, high acuity, tobacco smoke exposure-related diagnoses and non-intensive care admission. Of children screened for tobacco smoke exposure, 28% were positive. Children more likely to screen positive were non-Hispanic, had non-commercial insurance, and had tobacco smoke exposure-related diagnoses. NonAfrican American children triaged as low acuity were more likely to have tobacco smoke exposure, yet were less likely to be screened.

CONCLUSION

Despite national recommendations, current tobacco smoke exposure screening rates are low and fail to identify at-risk children. Pediatric emergency department visits for tobacco smoke exposure-associated conditions are common, thus further research is needed to develop and assess standardized tobacco smoke exposure screening tools/interventions in this setting.

Reduction of Secondhand Smoke Exposure in the Cars of Children With Cancer

This study examined whether an intervention designed to reduce secondhand smoke exposure (SHSe) among children being treated for cancer had effects in the specific setting of a motor vehicle. The parents or guardians (n = 71) of children being treated for cancer were randomized to either a behavioral secondhand smoke (SHS) reduction program or a standard care control group. Parental reports of SHSe were collected over the course of 12 months. Younger children were exposed at baseline more than their older counterparts. The greatest initial declines in car exposure were observed among children ≤5 years old in the intervention group compared with same-aged peers in the control group. After the 3-month time point, the control group showed greater reductions in car exposure in comparison with the intervention group. Interventions that teach parents strategies to manage their smoking while driving in their personal vehicles may produce even greater reductions in child exposure and should be developed. Based on the age-specific results reported here, future studies should account for effects of child age and use setting-specific measures of SHS.

Predictors of children's secondhand smoke exposure at home: a systematic review and narrative synthesis of the evidence

BACKGROUND

Children's exposure to secondhand smoke (SHS) has been causally linked to a number of childhood morbidities and mortalities. Over 50% of UK children whose parents are smokers are regularly exposed to SHS at home. No previous review has identified the factors associated with children's SHS exposure in the home.

AIM

To identify by systematic review, the factors which are associated with children's SHS exposure in the home, determined by parent or child reports and/or biochemically validated measures including cotinine, carbon monoxide or home air particulate matter.

METHODS

Electronic searches of MEDLINE, EMBASE, PsychINFO, CINAHL and Web of Knowledge to July 2014, and hand searches of reference lists from publications included in the review were conducted.

FINDINGS

Forty one studies were included in the review. Parental smoking, low socioeconomic status and being less educated were all frequently and consistently found to be independently associated with children's SHS exposure in the home. Children whose parents held more negative attitudes towards SHS were less likely to be exposed. Associations were strongest for parental cigarette smoking status; compared to children of non-smokers, those whose mothers or both parents smoked were between two and 13 times more likely to be exposed to SHS.

CONCLUSION

Multiple factors are associated with child SHS exposure in the home; the best way to reduce child SHS exposure in the home is for smoking parents to quit. If parents are unable or unwilling to stop smoking, they should instigate smoke-free homes. Interventions targeted towards the socially disadvantaged parents aiming to change attitudes to smoking in the presence of children and providing practical support to help parents smoke outside the home may be beneficial.

Active smoking, environmental tobacco smoke and bronchitic symptoms among adolescents in Taiwan: a prospective cohort study

OBJECTIVE

The study investigates the association between active smoking, exposure to environmental tobacco smoke (ETS) and the development of bronchitis and bronchitic symptoms among adolescents.

METHODS

A prospective cohort study was conducted with 4134 adolescents aged 12-14 from the Taiwan Children Health Study in 14 communities in Taiwan since 2007. Parents or guardians completed written questionnaires regarding demographic information, household ETS and respiratory symptoms at baseline. The adolescents themselves completed identical questionnaires on respiratory outcomes in the 2009 survey. Associations between active smoking, exposure to ETS and the 2-year incidence of respiratory outcomes were analyzed by multiple Poisson regression models, taking overdispersion into account.

RESULTS

Active smoking was associated with an increased risk of developing chronic cough and chronic phlegm. We found significant dose-response associations between the duration of smoking, the numbers of cigarettes and the onset of bronchitic symptoms. Exposure to ETS was a significant risk factor for the development of chronic cough. Among asthmatic adolescents, exposure to ETS was associated with an additional risk for the onset of chronic phlegm.

CONCLUSION

This study demonstrates that active smoking and exposure to ETS are associated with higher risks for developing bronchitic symptoms among adolescents.

Family and carer smoking control programmes for reducing children's exposure to environmental tobacco smoke

BACKGROUND

Children's exposure to other people's cigarette smoke (environmental tobacco smoke, or ETS) is associated with a range of adverse health outcomes for children. Parental smoking is a common source of children's exposure to ETS. Older children are also at risk of exposure to ETS in child care or educational settings. Preventing exposure to cigarette smoke in infancy and childhood has significant potential to improve children's health worldwide.

OBJECTIVES

To determine the effectiveness of interventions aiming to reduce exposure of children to ETS.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group Specialized Register and conducted additional searches of the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PsycINFO, EMBASE, CINAHL, ERIC, and The Social Science Citation Index & Science Citation Index (Web of Knowledge). Date of the most recent search: September 2013.

SELECTION CRITERIA

Controlled trials with or without random allocation. Interventions must have addressed participants (parents and other family members, child care workers and teachers) involved with the care and education of infants and young children (aged 0 to 12 years). All mechanisms for reduction of children's ETS exposure, and smoking prevention, cessation, and control programmes were included. These include health promotion, social-behavioural therapies, technology, education, and clinical interventions.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies and extracted data. Due to heterogeneity of methodologies and outcome measures, no summary measures were possible and results were synthesised narratively.

MAIN RESULTS

Fifty-seven studies met the inclusion criteria. Seven studies were judged to be at low risk of bias, 27 studies were judged to have unclear overall risk of bias and 23 studies were judged to have high risk of bias. Seven interventions were targeted at populations or community settings, 23 studies were conducted in the 'well child' healthcare setting and 24 in the 'ill child' healthcare setting. Two further studies conducted in paediatric clinics did not make clear whether the visits were to well or ill children, and another included both well and ill child visits. Thirty-six studies were from North America, 14 were in other high income countries and seven studies were from low- or middle-income countries. In only 14 of the 57 studies was there a statistically significant intervention effect for child ETS exposure reduction. Of these 14 studies, six used objective measures of children's ETS exposure. Eight of the studies had a high risk of bias, four had unclear risk of bias and two had a low risk of bias. The studies showing a significant effect used a range of interventions: seven used intensive counselling or motivational interviewing; a further study used telephone counselling; one used a school-based strategy; one used picture books; two used educational home visits; one used brief intervention and one study did not describe the intervention. Of the 42 studies that did not show a significant reduction in child ETS exposure, 14 used more intensive counselling or motivational interviewing, nine used brief advice or counselling, six used feedback of a biological measure of children's ETS exposure, one used feedback of maternal cotinine, two used telephone smoking cessation advice or support, eight used educational home visits, one used group sessions, one used an information kit and letter, one used a booklet and no smoking sign, and one used a school-based policy and health promotion. In 32 of the 57 studies, there was reduction of ETS exposure for children in the study irrespective of assignment to intervention and comparison groups. One study did not aim to reduce children's tobacco smoke exposure, but rather aimed to reduce symptoms of asthma, and found a significant reduction in symptoms in the group exposed to motivational interviewing. We found little evidence of difference in effectiveness of interventions between the well infant, child respiratory illness, and other child illness settings as contexts for parental smoking cessation interventions.

AUTHORS' CONCLUSIONS

While brief counselling interventions have been identified as successful for adults when delivered by physicians, this cannot be extrapolated to adults as parents in child health settings. Although several interventions, including parental education and counselling programmes, have been used to try to reduce children's tobacco smoke exposure, their effectiveness has not been clearly demonstrated. The review was unable to determine if any one intervention reduced parental smoking and child exposure more effectively than others, although seven studies were identified that reported motivational interviewing or intensive counselling provided in clinical settings was effective.

Interaction between glutathione S-transferase variants, maternal smoking and childhood wheezing changes with age

BACKGROUND

Maternal smoking increases the risk of respiratory symptoms in children. Glutathione S-transferases (GSTs) detoxify xenobiotics from tobacco smoke, and functional polymorphism in GST gene(s) could predispose children to the detrimental effects of maternal smoking. Our objective was to investigate interactions between GST variants and maternal smoking in relation to the development of wheezing during childhood and whether any such interaction changes with time.

METHODS

In a population-based birth cohort, we assessed maternal smoking and current wheeze at five time points during the first 11 yr of life. DNA was genotyped for GSTP1, GSTM1 and GSTT1 (n = 807). Longitudinal analyses were performed using generalized estimating equations.

RESULTS

During early childhood, children whose mothers smoked were more likely to wheeze, with the strongest association observed at age 3 yr (p = 0.006). In a longitudinal model, children with GSTP1 AA and AG genotypes had significantly higher risk of wheeze compared with GG homozygotes. We observed a significant interaction between GSTP1 and maternal smoking where the risk of infantile wheezing was significantly increased in AA homozygotes, but only if their mothers smoked (OR 2.59, [1.08-6.21], p(int) = 0.03). Furthermore, amongst AA carriers, there was a significant interaction between child's age and maternal smoking, with the effect of maternal smoking on the risk of wheeze significantly diminishing with age (p(int) = 0.05); no such findings were observed for GSTM1 and GSTT1.

CONCLUSIONS

Children with AA genotype for GSTP1 are at increased risk of early-life wheezing if their mothers smoke, but the effect of maternal smoking on wheezing diminishes with time.

CYP2A6 genotype but not age determines cotinine half-life in infants and children

The formation of cotinine, the main proximate metabolite and a biomarker of nicotine exposure, is mediated primarily by cytochrome P450 (CYP)2A6. Our aim was to determine whether higher cotinine levels in young children exposed to secondhand smoke (SHS) are a result of age-related differences in pharmacokinetics. Forty-nine participants, aged 2-84 months, received oral deuterium-labeled cotinine, with daily urine samples for up to 10 days for cotinine half-life measurement. DNA from saliva was used for CYP2A6 genotyping. The estimate of half-life using a mixed-effect model was 17.9 h (95% confidence interval: 16.5, 19.3), similar to that reported in adults. There was no statistically significant effect of sex, race, age, or weight. Children with normal-activity CYP2A6*1/*1 genotypes had a shorter half-life than those with one or two reduced-activity variant alleles. Our data suggest that higher cotinine levels in SHS-exposed young children as compared with adults are due to greater SHS exposure rather than to different cotinine pharmacokinetics.

Factors influencing exposure to secondhand smoke in preschool children living with smoking mothers

INTRODUCTION

The health effects on young children of exposure to secondhand smoke (SHS) are well described. Recent work suggests that over one quarter of school-aged children in Scotland are regularly exposed to SHS in the home. The study was designed to describe SHS exposure in preschool children whose mothers smoked and identify factors that influence exposure.

METHODS

Smoking mothers with at least one child aged 1-5 years were recruited to the Reducing Families' Exposure to Secondhand Smoke in the Home study. Concentrations of airborne particulate matter less than 2.5 μm in size (PM(2.5)) in the home were measured together with child's salivary cotinine. Demographics including age, accommodation type, socioeconomic status, and number of cigarettes smoked at home were recorded.

RESULTS

Data were collected from 54 homes. In 89% of the homes, concentrations of PM(2.5) exceeded health-based guidance values at some point of the day. Household PM(2.5) concentrations were highest during the evening hours of 6 p.m. to midnight. Younger children had higher salivary cotinine concentrations than older children, and the geometric mean of salivary cotinine was 2.36 ng/ml. Household smoking restrictions and maternal confidence in enforcing smoking restrictions in their own home were strongly associated with child's SHS exposure.

CONCLUSIONS

Preschool children's exposure to SHS in homes where the mother smokes is considerable. Interventions and policy development to increase parental awareness of the health effects of SHS and provide parents with the confidence to implement smoke-free households are required to reduce the SHS exposure of preschool age children.

Admission screening for secondhand tobacco smoke exposure

OBJECTIVES

Secondhand smoke (SHS) exposure is an important and preventable cause of mortality and morbidity among children; hospitalization represents a sentinel event that may offer opportunities for intervention. The goal of this study was to determine the frequency and validity of SHS exposure screenings by emergency department (ED) providers, residents, and nurses.

METHODS

A total of 140 inpatient pediatric families consented to a salivary cotinine measurement, in-person SHS exposure interview, and chart review to assess ED provider, pediatric resident, and nurse SHS exposure screenings and documentation validity.

RESULTS

ED providers documented screening for SHS exposure 46% of the time, pediatric residents 42% of the time, and nurses 79% of the time. ED providers, pediatric residents, and nurses reported 18%, 38%, and 12% of patients exposed to SHS, respectively, whereas 46% of patients were identified as smoke-exposed according to cotinine level and/or parent report. Those with SHS exposure outside the home were least likely to be identified as exposed.

CONCLUSIONS

The majority of smoke-exposed children were not identified as exposed based on documentation of admission screenings. Future research is important to identify accurate and efficient methods of screening for and identifying SHS exposure among children admitted to the hospital.

Provision of smoke-free homes and vehicles for kindergarten children: associated factors

Many children continue to be exposed to environmental tobacco smoke (ETS) each day. To describe the factors associated with providing a smoke-free home (PSFH) and vehicle (PSFV) for kindergarten children, a cross-sectional descriptive study was conducted in Manitoba, Canada, with 551 mothers and primary caregivers responding. A social-ecologic model of health behavior guided the study. In the bivariate analysis, being better educated, living with a partner, and having a higher income were associated with PSFH. In the multivariable logistic regression analysis, the variables most predictive for PSFH were living with a partner and the mother's self-efficacy, and for PSFV, the most predictive variables were the mother's self-efficacy and ETS knowledge. Smoking behaviors are complex and must be considered broadly within all levels of influence if nurses are to assist parents in protecting their children.

A methodology to establish a database to study gene environment interactions for childhood asthma

Background

Gene-environment interactions are likely to explain some of the heterogeneity in childhood asthma. Here, we describe the methodology and experiences in establishing a database for childhood asthma designed to study gene-environment interactions (PAGES - Paediatric Asthma Gene Environment Study).

Methods

Children with asthma and under the care of a respiratory paediatrician are being recruited from 15 hospitals between 2008 and 2011. An asthma questionnaire is completed and returned by post. At a routine clinic visit saliva is collected for DNA extraction. Detailed phenotyping in a proportion of children includes spirometry, bronchodilator response (BDR), skin prick reactivity, exhaled nitric oxide and salivary cotinine. Dietary and quality of life questionnaires are completed. Data are entered onto a purpose-built database.

Results

To date 1045 children have been invited to participate and data collected in 501 (48%). The mean age (SD) of participants is 8.6 (3.9) years, 57% male. DNA has been collected in 436 children. Spirometry has been obtained in 172 children, mean % predicted (SD) FEV₁ 97% (15) and median (IQR) BDR is 5% (2, 9). There were differences in age, socioeconomic status, severity and %FEV₁ between the different centres (p≤0.024). Reasons for non-participation included parents not having time to take part, children not attending clinics and, in a small proportion, refusal to take part.

Conclusions

It is feasible to establish a national database to study gene-environment interactions within an asthmatic paediatric population; there are barriers to participation and some different characteristics in individuals recruited from different centres. Recruitment to our study continues and is anticipated to extend current understanding of asthma heterogeneity.

Determinants of serum cotinine and hair cotinine as biomarkers of childhood secondhand smoke exposure

Understanding the determinants of childhood secondhand smoke (SHS) exposure is important in measuring and preventing exposure to this widespread environmental contaminant. We evaluated the ability of a broad set of factors to explain variability in serum cotinine, reflecting recent exposure, and hair cotinine, reflecting longer-term exposure. We included repeated measures from 223 elementary-school-age asthmatic children residing with a smoker. We used a manual model-building approach and likelihood ratio tests to select a model predicting each biomarker, and also compared the predictive ability of determinants using Akaike Information Criteria. Potential determinants included a comprehensive parent questionnaire, household nicotine, home ventilation characteristics, exposure in vehicles and others' homes, child demographics, and family social class. Variables in each of these categories remained in the final model for both serum (R(2) of 0.61) and hair cotinine (R(2) of 0.45). A comprehensive set of factors was required to best predict cotinine. Studies should use biomarkers for the best quantitative assessment of SHS exposure. Hair cotinine may be a problematic measure because it was highly influenced by racial differences that were unexplained by SHS exposure. When biospecimen collection is not possible, a household nicotine measurement is warranted. If only questionnaires are available, multiple questions are required to best characterize exposure, such as number of cigarettes, hours spent in a room with concurrent smoking, maternal smoking, and approximate home size.

Motivation to quit smoking among parents of urban children with asthma

OBJECTIVE

To identify factors associated with motivation to quit smoking among parents of urban children with asthma.

METHODS

We analyzed data from parents who smoke and had a child enrolled in the School-Based Asthma Therapy (SBAT) trial. We assessed asthma symptoms, children's cotinine, and parent smoking behaviors. Motivation to quit smoking was assessed by a 10-point continuous measure (1, not at all motivated; 10, very motivated).

RESULTS

209 parents smoked (39% of sample), and children's mean cotinine was 2.48 ng/ml. Motivation to quit was on average 6.9, and 47% of parents scored >or=8 on the scale. Parents who believed their child's asthma was not under good control, and parents who strongly agreed their child's asthma symptoms would decrease if they stop smoking had higher motivation to quit compared to their counterparts (p<.05). In a multivariate analysis, parents who believed their child's asthma was not under control had more than twice the odds of reporting high motivation to quit.

CONCLUSION

Parents' perception of the risks of smoking to their child with asthma is associated with motivation to quit.

PRACTICE IMPLICATIONS

Raising awareness about the effect of smoking and quitting on children's asthma might increase motivation to quit among parents.

Prevalence and correlates of smoking among urban adult men in Bangladesh: slum versus non-slum comparison

BACKGROUND

Smoking is one of the leading causes of premature death particularly in developing countries. The prevalence of smoking is high among the general male population in Bangladesh. Unfortunately smoking information including correlates of smoking in the cities especially in the urban slums is very scarce, although urbanization is rapid in Bangladesh and slums are growing quickly in its major cities. Therefore this study reported prevalences of cigarette and bidi smoking and their correlates separately by urban slums and non-slums in Bangladesh.

METHODS

We used secondary data which was collected by the 2006 Urban Health Survey. The data were representative for the urban areas in Bangladesh. Both slums and non-slums located in the six City Corporations were considered. Slums in the cities were identified by two steps, first by using the satellite images and secondly by ground truthing. At the next stage, several clusters of households were selected by using proportional sampling. Then from each of the selected clusters, about 25 households were randomly selected. Information of a total of 12,155 adult men, aged 15-59 years, was analyzed by stratifying them into slum (= 6,488) and non-slum (= 5,667) groups. Simple frequency, bivariable and multivariable logistic regression analyses were performed using SPSS.

RESULTS

Overall smoking prevalence for the total sample was 53.6% with significantly higher prevalences among men in slums (59.8%) than non-slums (46.4%). Respondents living in slums reported a significantly (P < 0.001) higher prevalence of smoking cigarettes (53.3%) as compared to those living in non-slums (44.6%). A similar pattern was found for bidis (slums = 11.4% and non-slums = 3.2%, P < 0.001). Multivariable logistic regression revealed significantly higher odds ratio (OR) of smoking cigarettes (OR = 1.12, 95% CI = 1.03-1.22), bidis (OR = 1.90, 95% CI = 1.58-2.29) and any of the two (OR = 1.23, 95% CI = 1.13-1.34) among men living in slums as compared to those living in non-slums when controlled for age, division, education, marital status, religion, birth place and types of work. Division, education and types of work were the common significant correlates for both cigarette and bidi smoking in slums and non-slums by multivariable logistic regressions. Other significant correlates of smoking cigarettes were marital status (both areas), birth place (slums), and religion (non-slums). Similarly significant factors for smoking bidis were age (both areas), marital status (slums), religion (non-slums), and birth place (both areas).

CONCLUSION

The men living in the urban slums reported higher rates of smoking cigarettes and bidis as compared to men living in the urban non-slums. Some of the significant correlates of smoking e.g. education and division should be considered for prevention activities. Our findings clearly underscore the necessity of interventions and preventions by policy makers, public health experts and other stakeholders in slums because smoking was more prevalent in the slum communities with detrimental health sequelae.

Methods for quantification of exposure to cigarette smoking and environmental tobacco smoke: focus on developmental toxicology

Active and passive smoking have been associated with an array of adverse effects on health. The development of valid and accurate scales of measurement for exposures associated with health risks constitutes an active area of research. Tobacco smoke exposure still lacks an ideal method of measurement. A valid estimation of the risks associated with tobacco exposure depends on accurate measurement. However, some groups of people are more reluctant than others to disclose their smoking status and exposure to tobacco. This is particularly true for pregnant women and parents of young children, whose smoking is often regarded as socially unacceptable. For others, recall of tobacco exposure may also prove difficult. Because relying on self-report and the various biases it introduces may lead to inaccurate measures of nicotine exposure, more objective solutions have been suggested. Biomarkers constitute the most commonly used objective method of ascertaining nicotine exposure. Of those available, cotinine has gained supremacy as the biomarker of choice. Traditionally, cotinine has been measured in blood, saliva, and urine. Cotinine collection and analysis from these sources has posed some difficulties, which have motivated the search for a more consistent and reliable source of this biomarker. Hair analysis is a novel, noninvasive technique used to detect the presence of drugs and metabolites in the hair shaft. Because cotinine accumulates in hair during hair growth, it is a unique measure of long-term, cumulative exposure to tobacco smoke. Although hair analysis of cotinine holds great promise, a detailed evaluation of its potential as a biomarker of nicotine exposure, is needed. No studies have been published that address this issue. Because the levels of cotinine in the body are dependent on nicotine metabolism, which in turn is affected by factors such as age and pregnancy, the characterization of hair cotinine should be population specific. This review aims at defining the sensitivity, specificity, and clinical utilization of different methods used to estimate exposure to cigarette smoking and environmental tobacco smoke.

Environmental tobacco smoke and behaviors of inner-city children with asthma

OBJECTIVE

To explore the relationship between environmental tobacco smoke (ETS) exposure and behavior among inner-city children with significant asthma.

METHODS

We analyzed baseline data for 200 children 4 to 10 years old who were enrolled in an asthma program. Environmental tobacco smoke exposure was measured by the child's salivary cotinine level. Caregivers completed the 28-item Behavior Problem Index (BPI). Positive responses were summed for a total BPI score, and children with scores >14 were considered to have significant behavior problems. We conducted Student t tests and multivariate regression analyses to determine the association of children's cotinine levels with BPI scores.

RESULTS

Overall, 56% of children were male, 65% were black, and 72% had Medicaid. Mean cotinine level was 1.47 ng/mL. Overall, 30% of children had total BPI scores >14. Children with cotinine values >1.47 ng/mL had significantly higher scores compared with children with lower cotinine values on total BPI (12.5 vs 10.2), as well as externalizing (9.0 vs 7.2), antisocial (2.3 vs 1.7), and immature (2.1 vs 1.6) subscales. In a multivariate model, log cotinine remained independently associated with externalizing (P = .04), headstrong (P = .04), and antisocial behavior (P = .04).

CONCLUSIONS

Cotinine levels are independently associated with problem behaviors among this sample of urban children with asthma.

Secondhand tobacco smoke in children with asthma: sources of and parental perceptions about exposure in children and parental readiness to change

BACKGROUND

Secondhand smoke triggers childhood asthma. Understanding sources of exposure, parental beliefs about exposure, and readiness to change that exposure are important for designing smoke exposure reduction interventions.

METHODS

As part of screening for a clinical trial of a smoke exposure reduction intervention, 519 smoke-exposed children 3 to 12 years old with asthma provided urine specimens for cotinine testing, and their primary caregivers completed questionnaires.

RESULTS

The urine cotinine to creatinine ratio (CCR) was lowest if neither the primary caregiver nor day-care provider smoked (mean CCR, 14.0; SD, 14.4), greater if either smoked (mean CCR, 22.2; SD, 21.3; and mean, CCR, 26.3; SD, 22.2, respectively), and greatest if both smoked (mean CCR, 39.6; SD, 27.5; p < 0.01). Parental perception of their child's exposure was weakly associated with the child's CCR (r(2) = 0.11, p < 0.001). Most parents (58.3%) reported that tobacco smoke exposure had small/no negative effect on their child's asthma. Substantial proportions of those for whom a specific exposure reduction action was relevant were classified as contemplating, preparing, or had recently taken action to reduce their child's exposure, including smoking cessation (61.3%), keeping the child out of smoke-exposed places (72.7%), and making the child's home (49.2%) and areas out of the home smoke free (66.9%).

CONCLUSIONS

Smoking by the primary caregiver and day-care provider are important sources of exposure for children with asthma. Parental assessment of their child's exposure is associated with biologically confirmed exposure but cannot be relied on to assess that exposure. Although the harm of smoke exposure was frequently underestimated, many parents appeared receptive to considering action to reduce their child's exposure.

TRIAL REGISTRATION

(Clinicaltrials.gov). Identifier: NCT00217958.

Smoking behavior in asthmatic and non-asthmatic adolescents: the role of smoking models and personality

Despite the particular health risks for asthmatics, recent international studies have reported that tobacco use among asthmatics is similar to, or even higher than, non-asthmatics. This study examined the role of personality and environment in smoking among asthmatic and non-asthmatic adolescents. In 2003 a random sample of 33 schools (first and second class of secondary education) was obtained in The Netherlands (N = 4,951). The mean age of the participants was 12.83 (SD = .75), and 52.8% were females. Information about asthma, smoking, personality, and environmental smoking was assessed via self-reports on standard epidemiology survey items (asthma, smoking) and the Quick Big Five (personality). Both personality and environmental smoking were associated with smoking. Asthmatics were similarly or even more exposed to environmental smoke than non-asthmatic adolescents and asthmatic adolescents were less emotionally stable and extravert. Associations between personality and own smoking behavior, as well as between smoking models and own smoking behavior were similar for asthmatic and non-asthmatics. Limitations of the study are taken notice of, and implications of the results are briefly discussed.

Evaluating environmental tobacco smoke exposure in a group of Turkish primary school students and developing intervention methods for prevention

Background

In countries like Turkey where smoking is highly prevalent, children's exposure to tobacco smoke is an important public health problem. The goals of this study were to determine the self-reported environmental tobacco smoke exposure status of primary school students in grades 3 to 5, to verify self-reported exposure levels with data provided from a biomarker of exposure, and to develop methods for preventing school children from passive smoking.

Methods

The study was conducted on 347 primary school students by using a standard questionnaire and urinary cotinine tests. Children with verified ETS exposure were randomly assigned to 2 intervention groups. Two phone interviews were conducted with the parents of the first group regarding their children's passive smoking status and its possible consequences. On the other hand, a brief note concerning urinary cotinine test result was sent to parents of the second group. Nine months after the initial urinary cotinine tests, measurements were repeated in both groups.

Results

According to questionnaire data, 59.9% of the study group (208 of 347) were exposed to ETS. Urinary cotinine measurements of children were highly consistent with the self-reported exposure levels (P < 0.001). Two different intervention methods were applied to parents of the exposed children. Control tests suggested a remarkable reduction in the proportion of those children demonstrating a recent exposure to ETS in both groups. Proportions of children with urinary cotinine concentrations 10 ng/ml or lower were 79.5% in Group I and 74.2% in Group II (P > 0.05).

Conclusion

Self-reported ETS exposure was found to be pretty accurate in the 9–11 age group when checked with urinary cotinine tests. Only informing parents that their childrens' ETS exposure were confirmed by a laboratory test seems to be very promising in preventing children from ETS.

Exposure to environmental tobacco smoke among children presenting to the emergency department with acute asthma: a multicenter study

Environmental tobacco smoke (ETS) exposure has been associated with increased use of the emergency department (ED) for acute asthma care. The purpose of this study was to determine the prevalence of ETS exposure among children presenting to the ED for acute asthma care and whether ETS exposure affects acute asthma severity or response to therapy. We conducted a multi-center study of children 2-11 years with physician-diagnosed acute asthma presenting to 44 EDs in 18 states. Chi-square test, Student's t-test, Wilcoxon rank sum test, and logistic regression were used for the analyses. The study population included 954 children. Thirty-six percent (95% CI, 33-39%) of caregivers reported that their child was exposed to ETS. Among exposed children, 35% were exposed 1-6 days/week, and 65% were exposed daily. Compared to unexposed children, ETS-exposed children were older at asthma diagnosis, older at ED presentation, and were less likely to be Hispanic. Indicators of chronic asthma severity were higher among unexposed children (i.e., total number of medications, use of controller medications, use of beta(2) agonists, number of urgent clinic visits, and lifetime hospitalizations). There was a weak association between ETS and acute asthma severity. Response to therapy (including ED disposition) did not differ between groups. On multivariate analysis, ETS-exposed children were more likely to be older, female, non-Hispanic, have lower household income, not use controller medications, and have a pet at home (all P < 0.05). Our study showed that the prevalence of ETS exposure among children presenting to the ED with acute asthma differs across demographic factors. There were no significant differences in acute asthma symptoms or response to ED therapy between ETS-exposed and unexposed children. Lower use of controller medications and less frequent urgent clinic visits among ETS-exposed children suggest inadequate asthma care or milder disease. The weak association between ETS exposure and acute asthma severity might reflect confounding by psychological factors and/or chronic asthma severity. The frequency of ETS exposure suggests that the ED may be an appropriate venue to engage caregivers of children with asthma in asthma education and smoking cessation efforts.

Predictors of the participation of smoking parents in a proactive telephone-based smoking cessation program

OBJECTIVE

The objective of this study is to identify the predictors of participation by smoking parents in a proactive telephone-based smoking cessation program.

METHODS

The smoking parents of young children from a birth cohort were interviewed and invited to take part in a telephone-based smoking cessation program. The characteristics of the parents and the predictors of participation were analyzed by chi-square test and by logistic regression.

RESULTS

A total of 952 (82.9%) out of the 1149 smoking parents who were interviewed agreed to participate in the smoking cessation program. The analysis showed that the predictors of participation in a pro-active smoking cessation program are being from a middle-income household, being currently employed, having recently had a medical consultation or been hospitalized, being at the stage of contemplating a change in behavior, and perceiving the importance of quitting smoking.

CONCLUSIONS

Recruitment approaches should be refined according to the identified factors to target those who might decline an invitation to participate in a smoking cessation program.

Impact of repeated lifestyle counselling in an atherosclerosis prevention trial on parental smoking and children's exposure to tobacco smoke

AIM

To determine whether repeated infancy-onset lifestyle counselling alters parental smoking and children's exposure to tobacco smoke.

METHODS

In 1990, 1062 healthy infants were recruited to a randomized, ongoing atherosclerosis prevention trial (STRIP). Intervention families received at least twice a year individualized nutrition and lifestyle counselling. By 1999, 652 8-y-old children continued participation. Exposure to tobacco smoke was evaluated using serum cotinine concentration. Parents' smoking was also assessed using questionnaires and interviews.

RESULTS

Parents' smoking decreased during the study similarly in the intervention and control groups. Of the 8-y-old children, 46% had detectable serum cotinine concentration, suggesting exposure to tobacco smoke during the past few days. All children were non-smokers. Serum cotinine concentrations did not differ between the intervention and control children. Children's cotinine values were highest in the families where either father or both parents were smokers.

CONCLUSION

Participation in the atherosclerosis prevention trial slightly decreased smoking among the intervention and control parents. However, counselling led to no differences in parental smoking between the two groups, or in exposure of the intervention and control children to tobacco smoke. This study suggests that more detailed and targeted intervention is required to achieve a significant effect on children's tobacco smoke exposure.

Passive cigarette smoke exposure in primary school children in Liverpool

OBJECTIVE

To assess environmental tobacco smoke (ETS) exposure amongst primary school children.

METHODS

A descriptive, community-based, cross-sectional study of self-reported parental smoking patterns and children's salivary cotinine concentrations in 245 children aged 5-11 years attending 10 primary schools in Liverpool.

RESULTS

The mean age was 7.4 years. The percentage of children living in smoking households was higher than the average reported for England (61.4% vs 53.0%). The average daily number of cigarettes smoked was similar for fathers (15.8) and mothers (16.4). The mean salivary cotinine concentration (+/-SD) was 1.6+/-0.4 ng/ml, and was higher in boys than girls (1.9+/-0.4 vs 1.2+/-0.2 ng/ml, P=0.006). The mean cotinine concentration was higher amongst children less than 7 years of age compared with older children (1.9+/-0.9 vs 1.4+/-0.6 ng/ml, P=0.01). Children from disadvantaged socio-economic households (Townsend score > + 6) had a mean cotinine level of 1.9+/-0.4 ng/ml, and a higher risk of a positive cotinine-validated level (>or=1 ng/ml) [crude odds ratio (OR) 3.5, 95% confidence interval (CI) 1.6-5.2). Maternal, but not paternal, cigarette smoke exposure was significantly associated with the salivary cotinine-validated level in children (adjusted OR 2.5, 95%CI 1.8-3.4).

CONCLUSIONS

Maternal smoking, age less than 7 years, child's gender (male) and low socio-economic status were significant risk factors associated with ETS exposure in young school children in Liverpool. The level of childhood ETS exposure in this area demonstrates a major public health concern that creates a challenge for innovative interactive strategies.

Is maternal smoking more determinant than paternal smoking on the respiratory symptoms of young children?

BACKGROUND

It is generally accepted that maternal smoking has more detrimental effects than paternal smoking on the respiratory health of children. The objective of this study was to assess the effects of postnatal exposure due to the smoking behaviour by father and mother in the home, and prenatal exposure from maternal smoking during pregnancy, on the respiratory symptoms in children.

METHODS

The parents of 484 children, aged 3-6 years, completed a questionnaire about smoking and respiratory symptoms in children. Bivariate and logistic regression analyses were used to examine the associated factors with respiratory symptoms.

RESULTS

The final model of logistic regression analysis showed that prenatal exposure by maternal smoking during pregnancy increased the risk of wheezing with colds (adjusted OR=2.00, 95% CI:1.13-3.55) with respect to those children whose mothers reported no smoking during pregnancy. Postnatal exposure by maternal smoking in the home, in the presence of the child, increased the risk of cough with phlegm (adjusted OR=2.79, 95% CI:1.23-6.30) with respect to those children whose mothers did not smoke in their presence. Paternal smoking was associated with wheezing and cough in the bivariate analysis, but did not remain significant in the multivariate analysis.

CONCLUSIONS

Our results underline a greater influence of exposure to maternal smoking (prenatal and postnatal) than postnatal paternal smoking on the development of respiratory symptoms in young children.

Possible association between passive smoking and lower exhaled nitric oxide in asthmatic children

In adults, both active and passive smoking reduce levels of exhaled nitric oxide (eNO); however, to date, passive exposure to environmental tobacco smoke (ETS) has not been shown to affect eNO in children. The authors recruited 174 asthmatic children (96 male, 78 female) and 79 nonasthmatic controls (46 male, 33 female) from a group of children aged 5 to 14 yr who attended a children's hospital for an outpatient visit or elective surgery. Each subject's exposure to ETS was ascertained by questionnaire, and their eNO levels were measured. Asthmatic children had higher eNO levels (ppb) than nonasthmatic children (p = 0.04), and asthmatic children exposed to ETS had significantly lower eNO levels than unexposed children (p = 0.005). Exposure to ETS did not alter eNO levels in nonasthmatic children (p = 0.4). Results of the study suggest that ETS exposure is associated with lower eNO levels among childhood asthmatics. Consequently, ETS exposure may need to be considered when physicians interpret eNO levels in asthmatic children. Further study of the effects of ETS on eNO levels is recommended.

Cholinergic systems in brain development and disruption by neurotoxicants: nicotine, environmental tobacco smoke, organophosphates

Acetylcholine and other neurotransmitters play unique trophic roles in brain development. Accordingly, drugs and environmental toxicants that promote or interfere with neurotransmitter function evoke neurodevelopmental abnormalities by disrupting the timing or intensity of neurotrophic actions. The current review discusses three exposure scenarios involving acetylcholine systems: nicotine from maternal smoking during pregnancy, exposure to environmental tobacco smoke (ETS), and exposure to the organophosphate insecticide, chlorpyrifos (CPF). All three have long-term, adverse effects on specific processes involved in brain cell replication and differentiation, synaptic development and function, and ultimately behavioral performance. Many of these effects can be traced to the sequence of cellular events surrounding the trophic role of acetylcholine acting on its specific cellular receptors and associated signaling cascades. However, for chlorpyrifos, additional noncholinergic mechanisms appear to be critical in establishing the period of developmental vulnerability, the sites and type of neural damage, and the eventual outcome. New findings indicate that developmental neurotoxicity extends to late phases of brain maturation including adolescence. Novel in vitro and in vivo exposure models are being developed to uncover heretofore unsuspected mechanisms and targets for developmental neurotoxicants.

Environmental tobacco smoke exposure in children: parental perception of smokiness at home and other factors associated with urinary cotinine in preschool children

Parental smoking behavior at home and sociodemographic variables may influence exposure to environmental tobacco smoke (ETS) in children. A sample of 115 preschool children aged 3-6 years was enrolled in this study. ETS exposure was evaluated through a questionnaire about parents' smoking behavior and determinations of urinary cotinine -- a biomarker of exposure -- in children. Bivariate and multiple regression analyses were used to evaluate the association between the smoking behavior of each parent at home, sociodemographic factors and cotinine levels in children. The parental perception of smokiness in the home was significantly associated with urinary cotinine in children (r-partial coefficient=0.324; P<0.002). The father's education, mother's smoking status, and day of the week when urine was sampled (Tuesday) were also independently associated with levels of cotinine. These four variables explained 26.4% of the variance in the cotinine levels of children. In designing educational programs to reduce passive smoking among children, it is necessary to take into account those factors related with cotinine levels in children. Our results support the influence of the mothers' smoking status, the fathers' educational level, and the day of the week of sampling on cotinine in children. The perception of parents (smokers and nonsmokers) about the smokiness in the home could also be a useful indicator of the cotinine in children exposed to environmental tobacco smoke in the household.

Repeated validation of parental self-reported smoking during pregnancy and infancy: a prospective cohort study of infants at high risk for allergy development

Exposure to environmental tobacco smoke (ETS) during fetal life and infancy is closely related to the smoking habits of the parents. Estimates of exposure to ETS require valid and detailed information on changes in cigarette smoking over time. The objective was to test the validity of self-reported smoking among parents during pregnancy and early childhood in a cohort of children at high risk for allergy development by measurement of exhaled carbon monoxide (CO). The cohort comprised 117 families enrolled from the general population of pregnant women at admission to antenatal care. Data on parental tobacco smoking were obtained by interview and exhaled CO was measured (Micro-Smokerlyzer(R)) in parents twice during pregnancy and when the child was 6 and 18 months old. The median (range) exhaled CO levels were 3 (0-10) parts per million (ppm) for non-smokers and 15 (1-39) ppm for smokers (P < 0.0005). A receiver operating characteristic (ROC) analysis was performed at each examination. The areas under the ROC curve were high for both mothers (between 0.88 and 0.99) and fathers (between 0.87 and 0.89), indicating exhaled CO as a good diagnostic tool for determining smoking status. Comparing the ROC areas obtained for mothers from late pregnancy and during infancy with the area from early pregnancy showed no statistical differences (P = 0.21, 0.43 and 0.44 respectively) and the same was true for fathers during infancy (P = 0.81). The level of 8 ppm was used as the cut-off between smokers and non-smokers, based on data from a pilot study. Using CO as a diagnostic tool for smoker status showed very high specificity (between 97 and 100%), indicating that very few persons claiming to be non-smokers had CO levels higher than 8 ppm. In conclusion, the validity of interview-obtained self-reported smoking among parents during pregnancy and early childhood was high. Repeated interviews and CO measurements in a prospective study design did not change the validity, indicating a low risk of information bias. A structured interview combined with measurement of exhaled CO is a valid and reliable method for estimating ETS exposure to the fetus and young infant.

Parental smoking and infant respiratory infection: how important is not smoking in the same room with the baby?

OBJECTIVES

We sought to quantify the effect of good smoking hygiene on infant risk of respiratory tract infection in the first 12 months of life.

METHODS

A cohort of 4486 infants in Tasmania, Australia, was followed from birth to 12 months of age for hospitalization with respiratory infection. Case ascertainment was 98.2%.

RESULTS

Relative to the infants of mothers who smoked postpartum but never in the same room with their infants, risk of hospitalization was 56% (95% confidence interval [CI] = 13%, 119%) higher if the mother smoked in the same room with the infant, 73% (95% CI = 18%, 157%) higher if the mother smoked when holding the infant, and 95% (95% CI = 28%, 298%) higher if the mother smoked while feeding the infant.

CONCLUSIONS

Parents who smoke should not smoke with their infants present in the same room.

Socioeconomic and ethnic group differences in self reported health status and use of health services by children and young people in England: cross sectional study

OBJECTIVES

To examine whether self reported health status and use of health services varies in children of different social class and ethnic group.

DESIGN

Cross sectional study from the 1999 health survey for England.

SUBJECTS

6648 children and young adults aged 2-20 years.

SETTING

Private households in England.

MAIN OUTCOME MEASURES

Proportion of children (or their parents) reporting episodes of acute illness in the preceding fortnight and prevalence of self reported longstanding illness. Proportion reporting specific illnesses. Proportion reporting that they had consulted a general practitioner in the preceding fortnight, attended hospital outpatient departments in the three preceding months, or been admitted to hospital in the preceding year.

RESULTS

Large socioeconomic differences were observed between ethnic subgroups; a higher proportion of Afro-Caribbean, Indian, Pakistani, and Bangladeshi children belonged to lower social classes than the general population. The proportion of children and young adults reporting acute illnesses in the preceding two weeks was lower in Bangladeshi and Chinese subgroups (odds ratio 0.41, 95% confidence interval 0.27 to 0.61 and 0.46, 0.28 to 0.77, respectively) than in the general population. Longstanding illnesses was less common in Bangladeshi and Pakistani children (0.52, 0.40 to 0.67 and 0.57, 0.46 to 0.70) than in the general population. Irish and Afro-Caribbean children reported the highest prevalence of asthma (19.5% and 17.7%) and Bangladeshi children the lowest (8.2%). A higher proportion of Afro-Caribbean children reported major injuries than the general population (11.0% v 10.0%), and children from all Asian subgroups reported fewer major and minor injuries than the general population. Indian and Pakistani children were more likely to have consulted their general practitioner in the preceding fortnight than the general population (1.86, 1.35 to 2.57 and 1.51, 1.13 to 2.01, respectively). Indian, Pakistani, Bangladeshi, and Chinese children were less likely to have attended outpatient departments in the preceding three months. No significant differences were found between ethnic groups in the admission of inpatients to hospitals. Acute and chronic illness were the best predictors of children's use of health services. Social classes did not differ in self reported prevalence of treated infections, major injuries, or minor injuries, and no socioeconomic differences were seen in the use of primary and secondary healthcare services.

CONCLUSIONS

Children's use of health services reflected health status rather than ethnic group or socioeconomic status, implying that equity of access has been partly achieved, although reasons why children from ethnic minority groups are able to access primary care but receive less secondary care need to be investigated.

Perinatal exposure to environmental tobacco smoke upregulates nicotinic cholinergic receptors in monkey brain

In humans, perinatal exposure to environmental tobacco smoke (ETS) is associated with neurobehavioral deficits. In the current study, we exposed Rhesus monkeys to ETS in late gestation and in the early neonatal period, and examined changes in neurotransmitter receptors in the brainstem and caudal portion of the cerebral cortex. Nicotinic acetylcholine receptors were markedly upregulated and the effect was selective in that there were no changes in m(2)-muscarinic acetylcholine receptors or in beta-adrenergic receptors. Nicotinic receptor upregulation is indicative of chronic cell stimulation by nicotine, and is a hallmark of nicotine-induced neuroteratogenesis. These results indicate that perinatal ETS exposes the fetus and neonate to quantities of nicotine that are sufficient to alter brain development.

Environmental tobacco smoke as a risk factor for respiratory disease in children

Respiratory diseases are a frequent reason for using health care. In 1995-1996, diseases of the respiratory tract (ICD 460-519) contributed seven of the top 15 reasons for visits to physician offices among children under 15 years of age in the United States. Environmental tobacco smoke (ETS) is a wide-spread environmental pollutant that has been long linked with respiratory problems. This paper will review the available literature on the role ETS plays in respiratory diseases, including asthma. This review focuses not only on the respiratory problems caused by ETS, but also examines the influence of age at exposure on the consequences of ETS and the importance of the differing sources of ETS exposure. As ETS is a completely preventable form of environmental pollution, the success or failure of various types of interventions will also be reviewed.

Predictors of cotinine levels in US children: data from the Third National Health and Nutrition Examination Survey

STUDY OBJECTIVE

To determine what factors predict cotinine levels in US children.

DESIGN

Cross-sectional study.

SUBJECTS

Nationally representative sample of 5,653 US children, both with and without reported tobacco smoke exposure in their homes.

METHODS

We stratified the children into those with reported passive smoke exposure at home and those without this exposure. We used regression models to predict the log of the cotinine level of the participants with the following independent covariates: age; race/ethnicity; number of rooms in the home; sex; parental education; family poverty index; family size; region; and, among children with reported passive smoke exposure, the number of cigarettes smoked in the home.

RESULTS

Children exposed to passive smoke had a mean cotinine level of 1.66 ng/mL, and children not exposed to passive smoke had a mean level of 0.31 ng/mL. Among children with reported smoke exposure, non-Mexican-American race/ethnicity, young age, low number of rooms in the home, low parental education, and an increasing number of cigarettes smoked in the home were predictors of increased serum cotinine levels. Among children with no reported smoke exposure, significant predictors of increased cotinine levels included black race, young age, Midwest region of the United States, low number of rooms in the home, low parental education, large family size, and low family poverty index.

CONCLUSION

While the reported number of cigarettes smoked in the home is the most important predictor of cotinine levels in children exposed to smoke and may provide an opportunity for clinical intervention, other demographic factors are important among children both with and without reported smoke exposure.

Perinatal exposure to environmental tobacco smoke induces adenylyl cyclase and alters receptor-mediated cell signaling in brain and heart of neonatal rats

Perinatal exposure to environmental tobacco smoke (ETS) has adverse effects on neurobehavioral development. In the current study, rats were exposed to ETS during gestation, during the early neonatal period, or both. Brains and hearts were examined for alterations in adenylyl cyclase (AC) activity and for changes in beta-adrenergic and m2-muscarinic cholinergic receptors and their linkage to AC. ETS exposure elicited induction of total AC activity as monitored with the direct enzymatic stimulant, forskolin. In the brain, the specific coupling of beta-adrenergic receptors to AC was inhibited in the ETS groups, despite a normal complement of beta-receptor binding sites. In the heart, ETS evoked a decrease in m2-receptor expression. In both tissues, the effects of postnatal ETS, mimicking passive smoking, were equivalent to (AC) or greater than (m2-receptors) those seen with prenatal ETS mimicking active smoking; the effects of combined prenatal and postnatal exposure were equivalent to those seen with postnatal exposure alone. These data indicate that ETS exposure evokes changes in cell signaling that recapitulate those caused by developmental nicotine treatment. Since alterations in AC signaling are known to affect cardiorespiratory function, the present results provide a mechanistic link reinforcing the participation of ETS exposure, including postnatal ETS, in disturbances culminating in events like Sudden Infant Death Syndrome.

The miseries of passive smoking

Passive smoking is defined as an involuntary exposure to a combined but diluted cigarette sidestream smoke (SS, gas and particle phases that are evolved from the smoldering end of a cigarette while the smoker is not puffing) and the exhaled smoke from smokers. SS contains numerous cytotoxic substances such as polycyclic aromatic hydrocarbons (PAHs), aromatic amines, nitrosamines, heavy metals, poisonous gases, pesticide residues, and radioactive elements in quantities much higher than those found from the cigarette mainstream smoke (MS) which is puffed by smokers. Passive smoking is found to be the cause of death from cancers and cardiac disease. Furthermore, it damagingly involves reproductive organs, the nervous system, genetic materials, and is particularly hazardous to mother and child during pregnancy and to those with a history of asthma, chronic infections, induced or earned immune deficiency, or predisposed susceptibility.

Does passive smoking increase the frequency of health service contacts in children with asthma?

BACKGROUND

Passive smoking is a major cause of respiratory morbidity in children. However, few studies give accurate estimates of the health effects of passive smoking in children with asthma using an objective measure of exposure. The effects of passive smoking using salivary cotinine levels to measure exposure were investigated.

METHODS

A sample of 438 children aged 2-12 years with asthma who had a parent who smoked were recruited in Tayside and Fife, Scotland. Health service contacts for asthma, assessed from GP case records, were used as a proxy for morbidity.

RESULTS

A weak U-shaped relationship was found between the salivary cotinine level and health service contacts for asthma: compared with low cotinine levels those with moderate cotinine levels had a reduced contact rate (relative rate (RR) = 0.91, 95% confidence interval (CI) 0.80 to 1.05), whereas high cotinine levels were associated with an increased rate of contact (RR = 1.19, 95% CI 1.05 to 1.37). In contrast, a strong association was seen with the amount the parent reported smoking in front of the child: the higher the level the fewer visits were made for asthma (RR for everyday exposure = 0.66, 95% CI 0.56 to 0.77). This effect was not seen for non-respiratory visits. Demographic factors, age of child, and number of children in the family all had a powerful effect on the number of visits for asthma. The parents' perception of asthma severity was associated with visit frequency independent of actual severity (derived from drug treatment).

CONCLUSION

High levels of parental smoking in the home are associated with a reduction in health care contacts for asthma. This could be due to a lack of awareness of asthma symptoms among heavy smokers or a reluctance to visit the GP. Children with asthma who have parents who smoke heavily may not be receiving adequate management.

Perinatal exposure to environmental tobacco smoke alters cell signaling in a primate model: autonomic receptors and the control of adenylyl cyclase activity in heart and lung

Perinatal exposure to environmental tobacco smoke (ETS) is known to have adverse effects on respiratory function in conjunction with changes in autonomic responses. In the current study, Rhesus monkeys were exposed to ETS during late gestation and in the early neonatal period. Hearts and lungs were examined for changes in beta-adrenergic and m2-muscarinic cholinergic receptors, and for alterations in adenylyl cyclase activity. Whereas there were no changes in the heart, there was robust induction of adenylyl cyclase in the lung; previous work with prenatal nicotine exposure in rodent models has shown that adenylyl cyclase induction is associated with a shift towards predominance of cholinergic over adrenergic responses. These data indicate that perinatal ETS exposure evokes changes in cells signaling that they are selective for the lung and that may ultimately reflect adverse effects at the level of physiological function.

Environmental tobacco smoke exposure among urban children

BACKGROUND

Environmental tobacco smoke (ETS) exposure is a well-known health hazard for children. Poor urban children may be at increased risk of exposure from nonparental sources of tobacco smoke. The unique problems of ETS exposure in urban children have previously not been well-defined.

OBJECTIVES

This study was conducted: 1) to identify the sources of ETS exposure for children attending a hospital-based pediatric resident practice; and 2) to examine caregivers' perceptions of the pediatrician's role and action in addressing ETS exposure.

DESIGN

Questionnaires were administered to a convenience sample of 174 caregivers of children visiting a children's hospital-based resident practice. A structured face-to-face interview was used.

RESULTS

All caregivers agreed to participate in the study. Most of the caregivers interviewed were mothers (87.9%). Although only 14% of caregivers were smokers, 49.4% reported caring for at least 1 smoke-exposed child. Most smoke exposure occurred in the home; smoking is allowed in the home of 75% of the children who live with a smoker (48/64). Thirty-four percent of the caregivers who reported no smoking in the home reported having a child who spends time in homes where other people smoke. Most exposure outside the home occurred at a grandparent's home. A ban on smoking in the home did not eliminate a child's risk of residential smoke exposure but did predict whether smoking occurred in the same room as the child. All caregivers reported believing that tobacco smoke is harmful. Approximately one half of caregivers who smoke (54.2%) would like smoking cessation advice from the child's pediatrician. Interest in receiving advice on helping others quit smoking was also high (51.3%) among nonsmoking caregivers who cared for a smoke-exposed child.

CONCLUSIONS

Nonparental sources of ETS exposure are reported to be common in urban children. Children may be exposed to tobacco smoke even in homes where smoking is banned. Many caregivers would like help from pediatricians in reducing children's exposure to tobacco smoke.

Smoking and pediatric respiratory health

Many children are exposed to smoking both prenatally and postnatally. Prenatal exposure to mainstream smoke from the mother and even to environmental tobacco smoke (ETS) from the mother in utero has been shown to change fetal lung development and cause airflow obstruction and airway hyperresponsiveness. Children exposed to ETS postnatally have more symptoms of cough, wheeze, respiratory illnesses, decreases in lung function, and increases in airway responsiveness. Smoke exposure is associated with the early development of asthma, increased severity of asthma, and the development of allergy. Finally smoke exposure is associated with sudden infant death and airway obstruction. This article reviews the spectrum of effects of cigarette smoke exposure on the respiratory health of infants and children and highlights basic science research exploring the mechanisms of these effects.

The relation between infant indoor environment and subsequent asthma

Our aim was to examine the contribution of an infant's indoor environment to childhood asthma using prospective data. We conducted a cross-sectional asthma survey in 1995 on 92% (6,378/6,911) of 7-year-olds in Tasmania, Australia. We linked these data with data collected in 1988 as part of the Tasmanian Infant Health Survey, which was designed to investigate sudden infant death. We were able to match 863 records out of the 1,111 in the 1988 survey and the 6,378 in the 1995 survey. The former group was interviewed at home at 1 month of age. In homes where at least one adult smoked in 1988, reported infant exposure to smoking in the same room in 1988 was associated with increased asthma by 1995 (relative risk = 1.52; 95% confidence interval = 1.01-2.29) after adjustment for confounders. The associations between infant exposure to environmental tobacco smoke and asthma were not consistent, however. Gas heater use in 1988 was associated with asthma (relative risk = 1.92; 95% confidence interval = 1.33-2.76). Markers of aeroallergen exposure at 1 month of age were not materially associated with asthma or wheeze. In some settings, air circulation practice with regard to bedroom door closure appeared important. Poor indoor air quality may play an important role in the development of childhood asthma.