Environmental tobacco smoke exposure as a risk factor for infections in infancy

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

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

Stepped-wedge cluster randomised trial of a smoking cessation counselling training programme for midwives treating women with functional health illiteracy and low socioeconomic status (PROMISE): a study protocol

Background

In the Netherlands, midwives are required to use the ‘V-MIS’ (Minimal Intervention Strategy for Midwives) smoking cessation counselling protocol to help pregnant women quit smoking. This counselling protocol is often poorly implemented in midwifery practices. It may also be less suitable for pregnant woman with low socioeconomic status or functional health illiteracy. We created an adapted version of the V-MIS protocol that is intended to facilitate implementation in midwifery practices: PROMISE (PROtocol for growing up smokefree using a Minimal smoking cessation Intervention Strategy in the Early stages of life). For this adapted protocol, midwives use carbon monoxide meters, storyboard leaflets, and specific communication techniques for women with functional health illiteracy. They will receive a face-to-face training in using these materials and communication techniques.

Methods

The effectiveness and implementation of PROMISE will be tested in a stepped-wedge cluster randomised controlled trial. We will randomise clusters of midwifery practices and departments in hospitals. We will then train them, subsequently, at regular intervals (‘steps’). At each step, practices that will receive training cross over from the control condition to the experimental condition. We will measure how well the PROMISE protocol has been implemented by assessing the rate of pregnant women that received detailed smoking cessation counselling from their midwives (primary outcome). Our secondary target group is pregnant women with functional health illiteracy and low socioeconomic status. Among them, we will assess smoking status and health-related outcome before and after pregnancy.

Discussion

The PROMISE smoking cessation counselling protocol is intended to help midwives, OB-GYNs, and other obstetrics professionals to support pregnant women with smoking cessation.

Trial registration

Dutch Trial Registry: NTR 6305/NL6158. Registered on 20 December 2016.

Risk factors for meningococcal disease in children and adolescents: a systematic review and META-analysis

Invasive meningococcal disease (IMD) remains a major cause of mortality and morbidity in children worldwide. A systemic review in PubMed and Cochrane Controlled Trials Register was performed for articles on risk factors for IMD in children and adolescents published during a 20-year period (19/09/1998 to 19/09/2018). Inclusion and exclusion criteria were established and applied. The data were meta-analyzed using random-effect model and the results were presented on forest plots separately for each risk factor. We identified 12,559 studies (duplicates removed). Titles, abstracts, and full texts were screened and finally, six studies (five case-control and one cohort study) were included in qualitative synthesis, five in meta-analysis. The median age of meningococcal disease (MD) cases was 72.2 months (0-19 years). Household crowding, smoking exposure, close relationships, and recent respiratory tract infections conferred a more than twofold risk for IMD in exposed individuals compared to controls [overcrowded living OR 2.52 (95% CI 1.75-3.63), exposure to smoke OR 2.10 (95% CI 1.00-4.39), kissing OR 2.00 (95% CI: 1.13-3.51), and recent respiratory tract infection OR 3.13 (95% CI 2.02-4.86)]. Attendance of religious events was associated with a decreased risk [0.47 (95% CI, 0.28-0.79)].Conclusion: Our review highlights the importance of individual characteristics as risk factors for IMD in childhood and adolescence. Preventive policies may consider individual as well as social-environmental factors to target individuals at risk.What is Known:• Close relationships, household crowding, and recent respiratory tract infections are major risk factors for IMD.• Passive smoking is a major risk factor for IMD.What is New:• Intimate kissing, household crowding, and passive smoking were found to double the risk of IMD.• Recent respiratory tract infections almost tripled the risk for IMD.

Self-Reported Environmental Tobacco Smoke Exposure and Avoidance Compared with Cotinine Confirmed Tobacco Smoke Exposure among Pregnant Women and Their Infants

BACKGROUND

Exposure to environmental tobacco smoke (ETS) presents substantial health risks for pregnant women and newborn infants. Measurements of ETS include invasive and expensive biochemical tests, as well as less invasive and lower-cost, self-reported exposure and avoidance measures. Better understanding of self-report measures will help to select ETS assessments for evaluation.

METHODS

This analysis was conducted within the context of a tailored video intervention to reduce tobacco smoking and ETS exposure during pregnancy and after delivery in the control group sample of 147 nonsmoking women. Measurements of salivary cotinine concentration, self-reported ETS exposure, and avoidance behaviors were captured at 32 weeks’ gestation and 6 months postpartum.

RESULTS

Salivary cotinine concentration was significantly related to ETS avoidance among pregnant nonsmokers at 32 weeks’ gestation, but not ETS exposure. At 6 months postpartum, both the reported ETS exposure of the infant and maternal avoidance behaviors to reduce her infant’s exposure were associated with the infant’s salivary cotinine concentration. At 32 weeks’ gestation and 6 months postpartum, avoidance behaviors decreased as exposure increased.

DISCUSSION

This study suggests that for nonsmoking women during pregnancy, reports of tobacco smoke avoidance are more valid than reports of exposure. After delivery, self-reported ETS exposure or avoidance are associated with each other and the biochemical measurement of salivary cotinine. These results provide researchers and clinicians with evidence to support the inclusion of avoidance behaviors in the selection of ETS measures.

Exploring young pregnant smokers' experiences with a self-nominated non-smoking buddy

INTRODUCTION

psychosocial interventions can increase the proportion of women who stop smoking in pregnancy. There is limited research exploring self-nominated, non-smoking buddy support, to assist young pregnant smokers to quit.

METHODS

this qualitative descriptive study was embedded within a randomised controlled study assisting young (16 to 24 years) pregnant smokers to quit. Women were recruited from two public maternity hospitals in Western Australia. Interviews were performed every two weeks from recruitment to six weeks post birth. The study aim was to explore women's experiences with a self-nominated non-smoking buddy. Thematic analysis was utilised to identify common themes.

FINDINGS

a total of 204 interviews were performed with 36 women, who had a mean of six interviews, with four conducted in pregnancy and two post birth. Two themes were revealed. The first 'Challenges of finding the right buddy' reflected the experiences women had in finding a non-smoking buddy to provide support and encompassed three sub themes; 'The only non-smoker I know', 'Reluctance to alter the existing relationship' and 'Limited discussion around expectations of buddy support'. The second theme 'Sustaining the buddy relationship' centred on the continuing relationship the woman had with her buddy and encompassed three sub themes; 'Consistent relationship', 'Changeable buddies' and 'Unofficial buddies'.

CONCLUSION

our findings reveal the complexity of incorporating non-smoking buddy support into smoking cessation programs for young pregnant smokers. The characteristics and social environment of individual women may have the capacity to influence their ability to engage and sustain a relationship with a non-smoking buddy.

Exposure to paternal tobacco smoking increased child hospitalization for lower respiratory infections but not for other diseases in Vietnam

Exposure to environmental tobacco smoke (ETS) is an important modifiable risk factor for child hospitalization, although its contribution is not well documented in countries where ETS due to maternal tobacco smoking is negligible. We conducted a birth cohort study of 1999 neonates between May 2009 and May 2010 in Nha Trang, Vietnam, to evaluate paternal tobacco smoking as a risk factor for infectious and non-infectious diseases. Hospitalizations during a 24-month observation period were identified using hospital records. The effect of paternal exposure during pregnancy and infancy on infectious disease incidence was evaluated using Poisson regression models. In total, 35.6% of 1624 children who attended follow-up visits required at least one hospitalization by 2 years of age, and the most common reason for hospitalization was lower respiratory tract infection (LRTI). Paternal tobacco smoking independently increased the risk of LRTI 1.76-fold (95% CI: 1.24-2.51) after adjusting for possible confounders but was not associated with any other cause of hospitalization. The population attributable fraction indicated that effective interventions to prevent paternal smoking in the presence of children would reduce LRTI-related hospitalizations by 14.8% in this epidemiological setting.

Tobacco smoke in infants with bronchopulmonary dysplasia

Exposure to tobacco smoke has been not evaluated in children with bronchopulmonary dysplasia (BPD). We evaluate the association of in utero smoking (IUS) and environmental tobacco smoke (ETS) with the respiratory events of BPD and non-BPD children. Two hundred sixty-two children born before 35 weeks of gestational age (GA) and regularly followed up in our regional network for preterms were enrolled. They were paired according to their BPD status, their gestational age and birth weight (131 children with BPD and 131 without BPD, 28 mean weeks GA; mean weight 1000 g). Respiratory data were obtained prospectively during their first 2 years of life. A complementary questionnaire was completed by the parents about their child's respiratory health at the age of 2, their home environment, and tobacco status. IUS concerned 12.6 %; ETS, 48.8 % (67 % in BPD children treated with oxygen at home). No further influence on respiratory outcome could be found by exposure to intrauterine smoke or extrauterine tobacco smoke in this patient sample.

CONCLUSION

IUS and ETS exposures are as high in preterm children as in a general pediatric population. The highest exposure occurs among BPD infants treated with oxygen at home.

WHAT IS KNOWN

• Environmental tobacco smoke (ETS) and in utero smoking (IUS) are responsible for many morphological, functional, and clinical changes in children. • Children with bronchopulmonary dysplasia (BPD) have more respiratory events in their first years of life than preterm children without BPB, maybe triggered by ETS and IUS. What is New: • The exposition to ETS and IUS is high in preterm children with and without BDP, as high as in a general. • Pedaitric population, particularly in children with BPD and treated with oxygen at home. • No further influence on respiratory outcome could be found by exposure to ETS or IUS in our studied population.

Particle exposures and infections

Particle exposures increase the risk for human infections. Particles can deposit in the nose, pharynx, larynx, trachea, bronchi, and distal lung and, accordingly, the respiratory tract is the system most frequently infected after such exposure; however, meningitis also occurs. Cigarette smoking, burning of biomass, dust storms, mining, agricultural work, environmental tobacco smoke (ETS), wood stoves, traffic-related emissions, gas stoves, and ambient air pollution are all particle-related exposures associated with an increased risk for respiratory infections. In addition, cigarette smoking, burning of biomass, dust storms, mining, and ETS can result in an elevated risk for tuberculosis, atypical mycobacterial infections, and meningitis. One of the mechanisms for particle-related infections includes an accumulation of iron by surface functional groups of particulate matter (PM). Since elevations in metal availability are common to every particle exposure, all PM potentially contributes to these infections. Therefore, exposures to wood stove emissions, diesel exhaust, and air pollution particles are predicted to increase the incidence and prevalence of tuberculosis, atypical mycobacterial infections, and meningitis, albeit these elevations are likely to be small and detectable only in large population studies. Since iron accumulation correlates with the presence of surface functional groups and dependent metal coordination by the PM, the risk for infection continues as long as the particle is retained. Subsequently, it is expected that the cessation of exposure will diminish, but not totally reverse, the elevated risk for infection.

Tobacco smoking, exposure to second-hand smoke, and asthma and wheezing in schoolchildren: a cross-sectional study

AIM

To analyse the association between tobacco smoking, exposure to second-hand smoke (SHS) and reports of wheezing and asthma in a sample of schoolchildren.

METHODS

A structured questionnaire was administered to 1766 students (7th grade, aged 12-13 years) at 25 schools in Terrassa, Spain (2006). We determined the prevalence of active smoking, exposure to SHS and reports of wheezing and asthma, and their association by means of prevalence odds ratios (OR) and 95% confidence intervals (CI).

RESULTS

97.5% of children were nonsmokers, 1.5% were experimental smokers and 1% were regular smokers. 41.1% of children reported exposure to SHS at home, 40.0% at school, 53.9% in their leisure time and 33.2% while using private or public transportation. Wheezing was reported by 9.2% of children, and 9.2% reported asthma. A significant association was found between smoking tobacco and wheezing: OR in experimental smokers = 3.0 (95% CI 1.2-7.7), and OR in active smokers = 4.2 (95% CI 1.4-12.5). Exposure to SHS while using transportation was associated with wheezing (OR = 1.4; 95% CI 1.0-2.0). Tobacco smoking and exposure to SHS were not associated with asthma.

CONCLUSION

Active and experimental smokers, and those who reported exposure to SHS while using public or private transportation, had higher likelihood of reporting wheezing. No association between active or passive smoking and asthma was observed.

Obesity and endocrine dysfunction programmed by maternal smoking in pregnancy and lactation

Obesity is a global epidemic, and maternal smoking has been shown to be associated with the development of childhood obesity. Overall, approximately 40% of children worldwide are exposed to tobacco smoke at home. It is well known that environmental changes within a critical window of development, such as gestation or lactation, can initiate permanent alterations in metabolism that lead to diseases in adulthood, a phenomenon called programming. It is known that programming is based on epigenetic alterations (changes in DNA methylation, histone acetylation, or small interfering RNA expression) that change the expression pattern of several genes. However, little is known concerning the mechanisms by which smoke exposure in neonatal life programs the adipose tissue and endocrine function. Here, we review several epidemiological and experimental studies that confirm the association between maternal nicotine or tobacco exposure during gestation or lactation and the development of obesity and endocrine dysfunction. For example, a positive correlation was demonstrated in rodents between increased serum leptin in the neonatal period and exposure of the mothers to nicotine during lactation, and the further development of leptin and insulin resistance, and thyroid and adrenal dysfunction, in adulthood in the same offspring. Thus, a smoke-free environment during the lactation period is essential to improving health outcomes in adulthood and reducing the risk for future diseases. An understanding of the pathophysiological mechanisms underlying the effects of smoking on programming can provide new insights into therapeutic strategies for obesity.

Associations among breastfeeding, smoking relapse, and prenatal factors in a brief postpartum smoking intervention

Postpartum smoking contributes to child health problems and is a barrier to breastfeeding, which promotes child health. There is a risk of postpartum smoking relapse for smokers and they are less likely to breastfeed. Understanding of smoking-breastfeeding associations must be improved. Enhancing smoking cessation advice simultaneously with breastfeeding counseling could increase smoking abstinence and breastfeeding rates. A low income sample of 31 volunteer maternal smokers and ex-smokers were recruited for this pilot intervention in an urban hospital's postpartum unit. Following pre-intervention interview, participants received either smoking relapse prevention plus breastfeeding counseling, or smoking relapse prevention only counseling. At one-month follow-up, we hypothesized that breastfeeding duration would positively relate to 7-day point prevalence abstinence rates and days to relapse and explored prenatal care and pregnancy smoking behavior associations with postpartum smoking and breastfeeding. Of the mothers, 75% completed follow-up. Days to relapse was related to duration of breastfeeding (r = 0.92, p = 0.08); however, counseling group differences in one-month smoking status were not significant. Earlier prenatal care initiation was associated with smoking abstinences at one month postpartum (chi(2) = 4.87, p <or= 0.05). Early prenatal care and breastfeeding is associated with postpartum smoking abstinence.