Passive smoking and the health of children

Effect of passive smoking exposure on risk of type 2 diabetes: a systematic review and meta-analysis of prospective cohort studies

Objective

The effect of passive smoking exposure on the risk of type 2 diabetes has not been systematically studied. A meta-analysis was conducted to assess the association between passive smoking exposure and the risk of diabetes.

Methods

We searched three major databases up to 31 October 2022 to identify relevant prospective cohort studies on the association between passive smoking and the risk of type 2 diabetes. The pooled relative risk (RR) and 95% confidence interval (CI) for the association between passive smoking exposure and the risk of type 2 diabetes were analyzed using a fixed-effect model.

Results

Ten prospective cohort studies were included in this meta-analysis, with a total of 251,620 participants involved. The pooled RR showed a significantly positive association between nonsmokers exposed to passive smoking and type 2 diabetes as compared to non-smokers who were not exposed to passive smoking [RR = 1.27; 95% CI (1.19, 1.36); p < 0.001]. Sensitivity analysis indicated that the pooled RR was not substantially affected by any of the individual studies.

Conclusion

Exposure to passive smoking increases the risk of type 2 diabetes. This study may have a positive effect on the prevention of type 2 diabetes.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42023372532.

Risk Factors for Wheezing in Primary School Children in Bursa, Turkey

Background

Wheezing is the most common symptom of childhood respiratory tract illnesses. It is important not only for its associated acute morbidity, but also for the fact that early childhood wheezing confers a high risk for asthma. Epidemiological studies from various countries show that 10–15% of children <1 year of age and 25% of children <5 years of age have wheezing-associated respiratory tract illness, and one-third of these children develop asthma later in life.

Methods

In this retrospective study, we evaluated the association between a history of wheezing and prenatal, postnatal, familial, and environmental risk factors in 858 7-year-old children, randomly selected from seven primary schools in Bursa, Turkey, by means of an easy-to-understand questionnaire form. Among these children, 12.4% had a history of early transient wheezing, 7.1% had persistent wheezing, and 7.7% had late onset wheezing; 72.8% had no wheezing symptoms and 33.3% of children who experienced wheezing during the first 3 years of life had physician-diagnosed asthma.

Results

Notable risk factors associated with wheezing were as follows: male gender, lower socioeconomic status, premature birth, maternal smoking during pregnancy, bottle-feeding before 2 months of age, dampness and mold at home, hospitalization due to any respiratory illness in infancy, history of croup between 6 months and 5 years of age, frequent upper respiratory infections during the first 3 years of life, allergic eczema in the child, and any allergic disease in the mother or siblings.

Conclusion

This study shows that the high rates of reported wheezing in the 858 primary school children in Bursa are clearly attributable to important risk factors that have long been recognized and discussed by researchers worldwide, and this suggests that all efforts at primary prevention may be insufficient.

A Tale of Smoking Cessation Promotion: The Utilization of a Children's Book to Increase Screening and Counseling in the Pediatric Clinic

OBJECTIVES

The rate at which pediatricians promote smoking cessation in clinical settings is low. The literature demonstrates that interventions paired with tangible health promotion materials may significantly increase screening rates to the pediatric office. The aim of this study was to investigate whether the addition of a children's book in the pediatric clinic could result in an increase in the rate in which pediatricians screened for secondhand smoke exposure (SHSe) and counseled caregivers to stop smoking.

STUDY DESIGN

This randomized controlled study was performed at 7 pediatric clinics.

METHODS

Seven pediatric clinic sites were randomly assigned to either an intervention or control group. Pediatricians in the intervention group were given children's books about SHSe to distribute to their patients while the control group did not receive any materials.

RESULTS

At baseline, there was no difference between the control group and intervention group in rates at which pediatricians screened for SHSe ( P = .8728) and counseled caregivers to stop smoking ( P = .29). After the intervention, screening for SHSe and counseling caregivers to stop smoking were statistically significantly greater in the intervention group, when compared to controls ( P < .01 and P < .001, respectively).

CONCLUSIONS

The use of a health promotion children's book in the pediatric setting can increase the rate at which pediatricians screen for SHSe and counsel caregivers to stop smoking. Future research should examine the effect of the storybook on various parameters of smoking cessation and future smoking behaviors.

Physiological effects of infant exposure to environmental tobacco smoke: a passive observation study

This study explored infant physiologic responses of exposure to environmental tobacco smoke (ETS) using a longitudinal passive observation study with a control group. Fifteen smoking and 15 non-smoking mothers were initially contacted in hospital maternity units, with home visits made when their infants were 2, 4, and 6 weeks old. Exposure to ETS was measured using infant urinary nicotine and cotinine levels. The physiologic effects of infant ETS exposure were measured by rectal temperature, pulse rate, respiratory rate, blood pressure, and oxygen saturation. The smoking mothers in this sample were poorer, had less education, and were less likely to be married than the mothers who did not smoke. At birth, the infants of smoking mothers had higher diastolic blood pressure than infants of non-smoking mothers (p < .008). Mothers who smoke cigarettes should be educated that maternal smoking behavior can affect an infant's cardiovascular function. Parents should also be counseled about the risks of smoking in close proximity and/or in an enclosed space with an infant, especially in a motor vehicle.

Urinary leukotriene E₄ levels identify children with tobacco smoke exposure at risk for asthma exacerbation

BACKGROUND

Children with asthma exposed to secondhand smoke (SHS) might be at higher risk for severe exacerbations, but biomarkers of susceptibility to SHS exposure have not been previously reported.

OBJECTIVES

We sought to assess the usefulness of urinary leukotriene E(4) (uLTE₄) levels in the prediction of increased risk of severe asthma exacerbations requiring emergency department (ED) or urgent care (UC) visits.

METHODS

Forty-four schoolchildren with moderate-to-severe asthma receiving inhaled corticosteroids were followed for 5 months with repeated measurements of uLTE₄ and monitoring of ED and UC visits. SHS exposure status was determined by using prestudy questionnaires and repeated measurements of urinary cotinine during the study.

RESULTS

Nine (45%) of 20 children with SHS exposure experienced a severe exacerbation requiring an ED or UC visit compared with 3 (12.5%) of 24 children without significant SHS exposure (relative risk, 3.6; 95% CI, 1.1-11.5; P = .02). The uLTE₄ level was a significant predictor of exacerbation risk in children exposed to SHS (area under the curve, 0.85; P = .003). Other predictors, such as nighttime symptom frequency, prebronchodilator and postbronchodilator lung function, and exhaled nitric oxide levels, were not related to exacerbations in this group. uLTE₄ levels at or greater than 106 pg/mg achieved 67% (6/9) sensitivity and 100% (11/11) specificity for predicting children with SHS exposure who required an ED or UC visit.

CONCLUSIONS

Children exposed to SHS are at increased risk for severe asthma exacerbations, despite use of inhaled corticosteroids. uLTE₄ levels identify children exposed to SHS at high risk for asthma exacerbations.

The response of children with asthma to ambient particulate is modified by tobacco smoke exposure

RATIONALE

Ambient particulate matter concentrations have been positively associated with urinary leukotriene E(4) (LTE(4)) levels and albuterol usage in children with asthma but interactions with environmental tobacco smoke (ETS) exposure have not been demonstrated despite obvious exposure to both pollutants in an urban setting.

OBJECTIVES

To assess the health effects of concurrent ETS and ambient particulate matter exposure in children with asthma.

METHODS

Albuterol usage and LTE(4) levels were monitored in 82 urban schoolchildren with asthma over three consecutive fall to spring school periods. Concentrations of morning maximum ambient particulate matter <2.5 μm in aerodynamic diameter (mmPM(2.5)) and urine cotinine levels were also measured daily.

MEASUREMENTS AND MAIN RESULTS

Albuterol usage and LTE(4) were related to mmPM(2.5) concentrations on days when urine cotinine levels were low (<10 ng/ml/mg creatinine); on these days, mean albuterol usage and LTE(4) increased up to 5 or 6% per 10 μg/m(3) increase in mmPM(2.5). In contrast, no significant relationship was observed when cotinine was high, although mean albuterol usage and LTE(4) levels were greater in this case. Model fits for LTE(4) levels as a function of mmPM(2.5) concentrations were improved when mmPM(2.5) concentrations were logged, suggesting a nonlinear dose-response relationship between particulate matter exposure concentrations and airway mediators of asthma, for which the relationship tends to flatten at higher concentrations.

CONCLUSIONS

This study suggests that ETS modifies the acute effects of low-level ambient PM(2.5) exposure on childhood asthma. This negative interaction, the smaller effect of particulate matter exposure in children exposed to higher ETS, may be related to a nonlinear dose-response relationship between asthma mediators and particulate exposures.

Relationships between cotinine, lower respiratory tract infection, and eosinophil cationic protein in children

INTRODUCTION

The aim of this study was to investigate the effect of passive smoking on urine eosinophil cationic protein (u-ECP) in children with lower respiratory tract infections (LRTI).

METHOD

This was a case-control study. The study cohort consisted of 150 children with LRTI (case group) and 150 healthy children (control), all from a urban setting. The statistical parameters were: a minimum of 139 children for a 95% confidence interval (95% CI), 80% power, and a possible exposure prevalence of 50%. The u-cotinine and u-ECP levels were measured by radioimmunoassay and fluoroimmunoassay methods, respectively. Data were analyzed by the McNemar chi-square test, t-test, and Pearson correlation.

RESULTS

When the generally accepted cut-off level of 30 ng/mg urinary cotinine/creatinine was applied, 87.3% of the children with LRTI and 84.7% of healthy children were passive smokers. Using a cut-off level of 60 ng/mg, passive smoking increased the prevalence of LRTI by 4.7-fold (p=0.000). The mean u-ECP values were significantly higher in the case group than in the healthy control group (p=0.018). A positive association was found between u-cotinine and u-ECP values in children with LRTI (p=0.034).

CONCLUSION

The results of this study indicate that passive smoking may play an important role in the development of respiratory infections and can cause airway inflammation in children with existing LRTI.

Guidelines for evaluating chronic cough in pediatrics: ACCP evidence-based clinical practice guidelines

OBJECTIVES

To review relevant literature and present evidence-based guidelines to assist general and specialist medical practitioners in the evaluation and management of children who present with chronic cough.

METHODOLOGY

The Cochrane, MEDLINE, and EMBASE databases, review articles, and reference lists of relevant articles were searched and reviewed by a single author. The date of the last comprehensive search was December 5, 2003, and that of the Cochrane database was November 7, 2004. The authors' own databases and expertise identified additional articles.

RESULTS/CONCLUSIONS

Pediatric chronic cough (ie, cough in children aged <15 years) is defined as a daily cough lasting for >4 weeks. This time frame was chosen based on the natural history of URTIs in children and differs from the definition of chronic cough in adults. In this guideline, only chronic cough will be discussed. Chronic cough is subdivided into specific cough (ie, cough associated with other symptoms and signs suggestive of an associated or underlying problem) and nonspecific cough (ie, dry cough in the absence of an identifiable respiratory disease of known etiology). The majority of this section focuses on nonspecific cough, as specific cough encompasses the entire spectrum of pediatric pulmonology. A review of the literature revealed few randomized controlled trials for treatment of nonspecific cough. Management guidelines are summarized in two pathways. Recommendations are derived from a systematic review of the literature and were integrated with expert opinion. They are a general guideline only, do not substitute for sound clinical judgment, and are not intended to be used as a protocol for the management of all children with a coughing illness. Children (aged <15 years) with cough should be managed according to child-specific guidelines, which differ from those for adults as the etiologic factors and treatments for children are sometimes different from those for adults. Cough in children should be treated based on etiology, and there is no evidence for using medications for the symptomatic relief of cough. If medications are used, it is imperative that the children are followed up and therapy with the medications stopped if there is no effect on the cough within an expected time frame. An evaluation of the time to response is important. Irrespective of diagnosis, environmental influences and parental expectations should be discussed and managed accordingly. Cough often impacts the quality of life of both children and parents, and the exploration of parental expectations and fears is often valuable in the management of cough in children.

Cough: are children really different to adults?

Worldwide paediatricians advocate that children should be managed differently from adults. In this article, similarities and differences between children and adults related to cough are presented. Physiologically, the cough pathway is closely linked to the control of breathing (the central respiratory pattern generator). As respiratory control and associated reflexes undergo a maturation process, it is expected that the cough would likewise undergo developmental stages as well. Clinically, the 'big three' causes of chronic cough in adults (asthma, post-nasal drip and gastroesophageal reflux) are far less common causes of chronic cough in children. This has been repeatedly shown by different groups in both clinical and epidemiological studies. Therapeutically, some medications used empirically for cough in adults have little role in paediatrics. For example, anti-histamines (in particular H1 antagonists) recommended as a front-line empirical treatment of chronic cough in adults have no effect in paediatric cough. Instead it is associated with adverse reactions and toxicity. Similarly, codeine and its derivatives used widely for cough in adults are not efficacious in children and are contraindicated in young children. Corticosteroids, the other front-line empirical therapy recommended for adults, are also minimally (if at all) efficacious for treating non-specific cough in children. In summary, current data support that management guidelines for paediatric cough should be different to those in adults as the aetiological factors and treatment in children significantly differ to those in adults.

Tobacco smoke exposure, wheeze, and atopy

We investigated the effect of in utero and postnatal environmental tobacco smoke (ETS) exposure on respiratory symptoms and atopy in the first 3 years of life in children at high risk of allergic disease (both parents atopic). Three hundred and sixty-nine children were followed from birth and reviewed at ages 1 and 3 years (respiratory questionnaire, skin testing). Parental smoking questionnaires were administered, and plasma cotinine in cord and peripheral blood (at age 1 year) was measured (capillary column gas-liquid chromatography). Wheezing starting in the first year of life was significantly more common in children of smoking mothers (54.2% vs. 39.5%, P = 0.017), but not wheezing starting after age 1 year (10.8% vs. 10.9%, smoking and nonsmoking mothers, P = 0.99). Detectable cord cotinine was not associated with wheeze. More frequent wheeze in infancy was significantly more common in those with detectable 1-year cotinine (e.g., wheeze without colds, 17.8% vs. 5.6%, P = 0.02; wheeze most days, 6.5% vs. 0%, P = 0.04). ETS exposure was not associated with atopy. In the multivariate regression analysis, maternal smoking during pregnancy and/or in the first year of life remained associated with wheeze in the first year of life (odds ratio, 1.88; 95% confidence interval, 1.14-3.12; P = 0.01). ETS exposure in "high-risk" infants increases the risk of wheezing starting in the first year of life, but not after age 1 year. However, ETS exposure has little or no effect on the development of atopy. Measurement of plasma cotinine was no more useful than tobacco exposure assessment by questionnaire in our cohort.

The association of maternal but not paternal genetic variation in GSTP1 with asthma phenotypes in children

Maternal factors including atopy and smoking during pregnancy are associated with asthma risk during childhood. Suggested mechanisms include transmission of specific maternal alleles and maternal influences on the intrauterine environment. We have previously shown that polymorphism in glutathione S-transferase, GSTP1 is associated with airway hyperresponsiveness (AHR) and atopy in adults. We now hypothesise that GSTP1 genotypes in the mother and child, but not the father, mediate asthma phenotypes in the child. One hundred and forty-five Caucasian families were recruited via an asthmatic proband aged 7-18 years. Atopy and asthma were assessed using a questionnaire, skin prick testing, serum IgE, spirometry and methacholine challenge (PC20, dose-response slope--DRS). GSTP1 genotyping was determined using PCR. GSTP1 Val105/Val105 genotype in the child was associated with a reduced risk of atopy (P = 0.038) and AHR (PC20, P = 0.046; DRS, P = 0.032). In mothers (P = 0.014) but not fathers (P = 0.623), Val105/Val105 was associated with a reduced risk of AHR in the child. We have identified, for the first time, an association between maternal genotype and the child's asthma phenotype that appears not to be due to transmission of specific maternal alleles. This preliminary data supports the view of in utero effects of maternal genotype and adds new insights into the possible mechanisms by which maternal factors may influence development of childhood asthma.

Assessment of the child with recurrent chest infections

The child with recurrent chest infections presents the clinician with a difficult diagnostic challenge. Does the child have a simply-managed cause for their symptoms, such as recurrent viral respiratory infections or asthma, or is there evidence of a more serious underlying pathology, such as bronchiectasis? Many different disorders present in this way, including cystic fibrosis, a range of immunodeficiency syndromes, and congenital abnormalities of the respiratory tract. In some affected children, lung damage follows a single severe pneumonia: in others it is the result of inhalation of food or a foreign body. The assessment of these children is demanding: it requires close attention to the history and examination, and in selected cases, extensive investigations. Early and accurate diagnosis is essential to ensure that optimal treatment is given and to minimise the risk of progressive or irreversible lung damage. The aim of this chapter is to examine the causes of recurrent chest infections and to describe how this complex group of children should be assessed and investigated.

Parental smoking: asthma and wheezing illnesses in infants and children

Parental smoking has an important impact on asthma and wheezing illnesses in infants and children. In utero exposure is associated with impaired lung growth and wheezing illnesses, particularly in preschool children. Exposure to environmental tobacco smoke is associated with increased wheezing illnesses and increased symptoms in asthmatics. There are no consistent data to confirm an effect of in utero or postnatal cigarette smoke exposure on the prevalence of asthma but there is evidence of increased severity of symptoms. The detrimental effects of parental smoking on lung growth will have an impact on respiratory health throughout life.

Risk factors for severe pneumonia in children in Basrah

A case-control study was undertaken in Basrah Maternity and Children Hospital, Iraq. We studied 148 children who were admitted to hospital with severe pneumonia according to the World Health Organization (WHO) criteria and the controls were 250 children attending the out-patient department for non-severe respiratory infections. Significant risk factors were younger age (2-6 months), low parental education, smoking at home, prematurity, weaning from breast milk at < 6 months, a negative history of diphtheria, pertussis and tetanus vaccination, anaemia and malnutrition.

A review of cough in children

Cough is a very common symptom of respiratory disease and reason for parents to seek medical attention. The article presents broad clinical guidelines on the approach to childhood cough and discusses current controversies of the management of cough in children.

How to prevent exposure to tobacco smoke among small children: a literature review

There are many reviews of current knowledge about smoking cessation in general within the health service, which also contain guidelines about smoking cessation during pregnancy. Our aim was to review methods in child healthcare for preventing the exposure of children to tobacco smoke. Since passive smoking starts during pregnancy, we also considered methods in antenatal care. We did a search for relevant articles, especially on randomized, controlled trials, in various databases, chiefly Medline. We mainly analysed studies from the last 10 y, concentrating on the actual interventions. In antenatal care the greatest effect comes from interventions based on behavioural strategies. These can lead to a doubling of the number of women who stop smoking during pregnancy. Purely factual information, on the other hand, has no great effect. The studies in child healthcare analysed here show that decisive factors for children not being exposed to passive smoking are a concentration on strengthening the parents' faith in their ability to create a smoke-free environment, and on behavioural strategies to achieve this goal, but not primarily on getting the parents to stop smoking. However, we need further studies of different types of interventions, geared to smokers with small children, before more specific recommendations can be given as to how child healthcare should design its tobacco-preventive work.

Respiratory effects of environmental tobacco smoke in a panel study of asthmatic and symptomatic children

The effect of environmental tobacco smoke (ETS) on respiratory health was investigated among 7- to 12-yr-old children with asthmatic (n = 74) or cough (n = 95) symptoms. For 3 mo the children measured their peak expiratory flow rate (PEFR) every morning and evening, and kept a daily diary of respiratory symptoms. They also noted daily whether they had used respiratory medication and whether someone had smoked inside their home. Eleven percent of the asthmatic children and 14% of the children with cough had exposure to ETS at home during the study. In multiple regression and analyses controlling for potential confounders, any exposure to ETS during the study was associated with a reduction of 42 L/min (95% confidence interval [CI]: 10 to 74 L/min) in morning and 41 L/min (95% CI: 8 to 74 L/min) in evening PEFR among asthmatic children. Among these children, a dose-dependent increase in the effect of ETS was also seen. Daily variation in ETS exposure was only weakly (-9.2 L/min; 95% CI: 2.9 to 21.2 L/min) associated with PEFR, but the previous day's ETS exposure was a risk factor for bronchodilator use (relative risk [RR]: 10.3; 95% CI: 1.3 to 83.7), as well as for cough (RR: 12.4; 95% CI: 2.4 to 63.3) and phlegm production (RR: 7. 8; 95% CI: 1.4 to 41.7), on any given day. Among children with cough only, there was only a weak suggestion of any possible ETS effect. In conclusion, we found that exposure to ETS was associated with a decline in peak flow and increases in respiratory symptoms and use of bronchodilator drugs among asthmatic children.

Measuring infant exposure to environmental tobacco smoke

Methods to measure infant exposure to environmental tobacco smoke (ETS) are needed to identify infants at highest risk for ETS-related health problems. The purpose of this study was to validate measures sensitive to changes in levels of infant exposure to ETS and to develop a predictive model of infant exposure to ETS. Fifteen infants of smoking mothers were followed from birth to 6 weeks of age. Exposure to ETS was measured by using a smoking habits questionnaire, cigarette "butt" collection, infant urine nicotine and cotinine levels, and ambient nicotine (personal air monitors). The 24-hour cigarette butt collection was the best predictor of acute (adjusted r2 = .83) and chronic exposure (adjusted r2 = .47) measured by infant urinary nicotine and cotinine levels when the infants were 2 weeks of age. Including scores on the smoking habits questionnaire and ambient nicotine levels increased the adjusted r2 to .88 and .61, respectively.

Meta-analysis on the association between environmental tobacco smoke (ETS) exposure and the prevalence of lower respiratory tract infection in early childhood

The aim of this study was to obtain quantitative information from published data on the association between environmental tobacco smoke (ETS) exposure and the prevalence of serious lower respiratory tract infections (LRTI) in infancy and early childhood. We identified 21 relevant publications on the relation between ETS and the prevalence of serious LRTI by reviewing reference lists in relevant reports and by conducting manual and computer searches (Medline database; Dissertation abstracts index of Xerox University Microfilms) of published reports between 1966 and 1995. Thirteen studies were included in a quantitative overview using random effects modeling to derive pooled odds ratios. Sensitivity analyses were conducted to test the decision rules used in extracting odds ratio data. The results of community and hospital studies are broadly consistent and show that the child of a parent who smokes is at approximately twice the risk of having a serious respiratory tract infection in early life that requires hospitalization. This association was pronounced in children younger than age two and diminished after the age of two. The combined odds ratio for hospitalization for lower respiratory tract infections in infancy or early childhood is 1.93 (95% CI 1.66-2.25); the combined odds ratio of prevalence of serious LRTI at age less than 2 years, between 0 and 6 years, and between 3 and 6 years were 1.71 (95% CI 1.33-2.20); 1.57 (1.28-1.91), and 1.25 (0.88-1.78), respectively. There was no evidence of heterogeneity across the studies in these combined odds ratios. We conclude that this meta-analysis provides strong evidence that exposure to ETS causes adverse respiratory health outcomes such as either a serious LRTI or hospitalization for LRTI. New public health campaigns are urgently needed to discourage smoking in the presence of young children.

Tobacco smoke exposure in children and adolescents with diabetes mellitus

AIMS

To examine active and passive tobacco smoke exposure in children and adolescents attending a diabetic clinic.

METHODS

Salivary cotinine concentrations were measured by gas chromatography and questionnaire data on the smoking habits of patients, families and friends were analysed as well as recording of glycosylated haemoglobin (HbA1c), body mass index (BMI) and social deprivation score.

RESULTS

Salivary cotinine concentrations identified 7% of the patients as active smokers and 72% as passive smokers. The mean cotinine concentration in those with no identifiable source of exposure was 0.10 (95% confidence interval 0.05-0.14) ng/ml, 2.81 (2.24-3.38) ng/ml in the passive smoking group and 1003.69 (55.96-151.41) ng/ml in the active smokers. Cotinine concentrations in passive smokers increased with the number of sources of exposure. The mean cotinine concentration was also higher when the mother was the sole source compared to other sources. There was no statistically significant correlation to smoking exposure and HbA1c BMI and deprivation scores.

CONCLUSION

Tobacco smoke exposure may pose serious health risks to children and adolescents with diabetes and additional public health measures are required to reduce overall exposure.

School-age follow-up of prophylactic versus rescue surfactant trial: pulmonary, neurodevelopmental, and educational outcomes

BACKGROUND

Exogenous surfactant replacement has improved survival and reduced pulmonary complications of prematurity. Improved early outcomes for infants of <30 weeks' gestation treated with a strategy of prophylactic versus rescue surfactant, if needed, were demonstrated in a multicenter, randomized trial conducted between 1985 and 1988. We reevaluated a subset of survivors from this trial to determine the pulmonary and neurodevelopmental outcomes at school age.

METHODS

At 4.5 to 8 years of age, all survivors from one of the three centers were located, and 96% were evaluated. The original randomization included stratification by center and followed an intention-to-treat methodology in assessing the efficacy of prophylactic versus rescue treatment with surfactant. The follow-up test battery included a health-assessment questionnaire, spirometry, 88% saturation test, neurologic examination, and the McCarthy Scales of Children's Abilities (MSCA) and the Conners' Parent Rating Scale-48. Educational achievement was determined by school class placement and teachers' reports of achievement.

RESULTS

Of the 192 children originally enrolled, 154 survived. Evaluations were performed on 148 of these infants. An abnormal pulmonary history was found in 45 (30%) of the children: 16 (22%) in the prophylactic group and 29 (39%) in the rescue group. Formal pulmonary function was evaluated in 81 children; 29 (78%) in the prophylactic group and 33 (75%) in the rescue group were considered abnormal. No significant differences were found between the two groups on either cognitive or motor subscales of the MSCA, the Conners' Parent Rating Scale-48, the neurologic examination, the education services received in school, or the teacher ratings of below-average academic performance. Intelligence scores measured on the MSCA were low-normal for both groups. Some level of educational assistance was being provided to 72 (49%) of the cohort studied, and both groups had below average educational performance and increased needs for educational assistance.

CONCLUSIONS

Prophylactic surfactant administration to infants of <30 weeks' gestation was associated with fewer long-term clinical pulmonary complications than assignment to rescue administration. Formal pulmonary testing at school age did not reveal significant differences between treatment groups in those infants who could be tested. There also were no group differences found on neurologic, cognitive, behavioral, or educational assessments at school age.

What determines levels of passive smoking in children with asthma?

BACKGROUND

Children with parents who smoke are often exposed to high levels of environmental tobacco smoke, and children with asthma are particularly susceptible to the detrimental effects of passive smoking. Data were collected from parents who smoke and from their asthmatic children. The families are currently taking part in a randomised controlled trial to test an intervention designed to reduce passive smoking in children with asthma. This paper reports on the baseline data. Questionnaire data and cotinine levels were compared in an attempt to assess exposure and to identify factors which influence exposure of the children. The aim of the study was to identify the scope for a reduction in passive smoking by these children.

METHODS

A sample of 501 families with an asthmatic child aged 2-12 years was obtained. Factors influencing passive smoking were assessed by interviewing parents. Cotinine levels were measured from saliva samples using gas liquid chromatography with nitrogen phosphorous detection.

RESULTS

Cotinine levels in children were strongly associated with the age of the child, the number of parents who smoked, contact with other smokers, the frequency of smoking in the same room as the child, and crowding within the home. Parental cotinine levels, the amount smoked in the home, and whether the home had a garden also exerted an independent effect on cotinine levels in the children.

CONCLUSIONS

Many children are exposed to high levels of environmental tobacco smoke and their cotinine levels are heavily dependent upon proximity to the parent who smokes. Parents who smoke have a unique opportunity to benefit their child's health by modifying their smoking habits within the home.

Parental and neonatal risk factors for atopy, airway hyper-responsiveness, and asthma

BACKGROUND

Previous studies have not resolved the importance of several potential risk factors for the development of childhood atopy, airway hyperresponsiveness, and wheezing, which would allow the rational selection of interventions to reduce morbidity from asthma. Risk factors for these disorders were examined in a birth cohort of 1037 New Zealand children.

METHODS

Responses to questions on respiratory symptoms and measurements of lung function and airway responsiveness were obtained every two to three years throughout childhood and adolescence, with over 85% cohort retention at age 18 years. Atopy was determined by skin prick tests at age 13 years. Relations between parental and neonatal factors, the development of atopy, and features of asthma were determined by comparison of proportions and logistic regression.

RESULTS

Male sex was a significant independent predictor for atopy, airway hyper-responsiveness, hay fever, and asthma. A positive family history, especially maternal, of asthma strongly predicted childhood atopy, airway hyperresponsiveness, asthma, and hay fever. Maternal smoking in the last trimester was correlated with the onset of childhood asthma by the age of 1 year. Birth in the winter season increased the risk of sensitisation to cats. Among those with a parental history of asthma or hay fever, birth in autumn and winter also increased the risk of sensitisation to house dust mites. The number of siblings, position in the family, socioeconomic status, and birth weight were not consistently predictive of any characteristic of asthma.

CONCLUSIONS

Male sex, parental atopy, and maternal smoking during pregnancy are risk factors for asthma in young children. Children born in winter exhibit a greater prevalence of sensitisation to cats and house dust mites. These data suggest possible areas for intervention in children at risk because of parental atopy.

Incidence and prognosis of asthma and wheezing illness from early childhood to age 33 in a national British cohort

OBJECTIVE

To describe the incidence and prognosis of wheezing illness from birth to age 33 and the relation of incidence to perinatal, medical, social, environmental, and lifestyle factors.

DESIGN

Prospective longitudinal study.

SETTING

England, Scotland and Wales.

SUBJECTS

18,559 people born on 3-9 March 1958. 5801 (31%) contributed information at ages 7, 11, 16, 23, and 33 years. Attrition bias was evaluated using information on 14, 571 (79%) subjects.

MAIN OUTCOME MEASURE

History of asthma, wheezy bronchitis, or wheezing obtained from interview with subjects' parents at ages 7, 11, and 16 and reported at interview by subjects at ages 23 and 33.

RESULTS

The cumulative incidence of wheezing illness was 18% by age 7, 24% by age 16, and 43% by age 33. Incidence during childhood was strongly and independently associated with pneumonia, hay fever, and eczema. There were weaker independent associations with male sex, third trimester antepartum haemorrhage, whooping cough, recurrent abdominal pain, and migraine. Incidence from age 17 to 33 was associated strongly with active cigarette smoking and a history of hay fever. There were weaker independent associations with female sex, maternal albuminuria during pregnancy, and histories of eczema and migraine. Maternal smoking during pregnancy was weakly and inconsistently related to childhood wheezing but was a stronger and significant independent predictor of incidence after age 16. Among 880 subjects who developed asthma or wheezy bronchitis from birth to age 7, 50% had attacks in the previous year at age 7; 18% at 11, 10% at 16, 10% at 23, and 27% at 33. Relapse at 33 after prolonged remission of childhood wheezing was more common among current smokers and atopic subjects.

CONCLUSION

Atopy and active cigarette smoking are major influences on the incidence and recurrence of wheezing during adulthood.

Passive smoking in childhood

There is increasing interest in the effects of adult smoking on the health of infants and children. Although passive smoking is important in many childhood disorders, most attention has been paid to its effects on the respiratory tract and on infant mortality. Several studies have reported an increased risk of sudden infant death syndrome and respiratory illness in infants of mothers who had smoked during pregnancy. Post-natal exposure to passive smoking has been found responsible for an increased risk of acute respiratory illness morbidity and an increased occurrence of chronic respiratory symptoms. Maternal cigarette smoking aggravates asthma symptoms and bronchial responsiveness in children with an established diagnosis of the disease, and the possibility that passive smoking has a causal role in the aetiology of asthma is currently a matter of growing interest. In addition, several studies have shown small but significant reductions in lung function values of children exposed to passive smoking.