Smoking and the sudden infant death syndrome

The vicious spiral in Sudden Infant Death Syndrome

Sudden Infant Death Syndrome (SIDS) is the sudden and unexpected death of an otherwise healthy infant less than 1 year of age where the cause of death remains unexplained after a thorough post-mortem investigation and evaluation of the circumstances. Epidemiological, clinical, biochemical, immunological and pathological evidence indicates that three factors must coincide for SIDS to occur: a vulnerable developmental stage of the immune system and central nervous system in the infant, predisposing factors, and external trigger events. This model is referred to as the fatal triangle or triple risk hypothesis. The concept of a vicious spiral in SIDS, starting with the fatal triangle and ending in death, is proposed as a model to understand the death mechanism. The vicious spiral is initiated by a mucosal infection and immune activation in the upper respiratory and digestive tracts, increased production of cytokines, and an overstimulation of the immature and rapidly developing immune system. A second trigger is the prone sleeping position, which may lead to rebreathing and hypercapnia, in addition to intensify the immune stimulation. In susceptible infants, this induces an aberrant cytokine production that affects sleep regulation, induces hyperthermia, and disrupts arousal mechanisms. In turn, this initiates downregulation of respiration and hypoxemia, which is worsened by nicotine. Inefficient autoresuscitation results in severe hypoxia and accumulation of hypoxic markers which, if not prevented by a normally functioning serotonergic network, contribute to a self-amplifying vicious spiral that eventually leads to coma and death. The purpose of this review is to summarize the research that underpins the concept of the vicious spiral.

Unexplained Infant Deaths Without Unsafe Sleep Factors: 2011 to 2020

OBJECTIVES

To describe sudden unexpected infant deaths (SUIDs) occurring in safe sleep environments and explore differences in selected characteristics.

METHODS

We examined SUID from 22 jurisdictions from 2011 to 2020 and classified them as unexplained, no unsafe sleep factors (U-NUSF). Data were derived from the Sudden Unexpected Infant Death and Sudden Death in the Young Case Registry, a population-based Centers for Disease Control and Prevention surveillance system built on the National Center for Fatality Review and Prevention's child death review program. SUID classified as U-NUSF included infants who were (1) awake, under supervision, and witnessed to become unresponsive or (2) found unresponsive in a safe sleep environment after sleep (unwitnessed). We calculated frequencies and percentages for demographics, birth and environmental characteristics, medical history, and death investigation findings.

RESULTS

Most of the 117 U-NUSF SUID occurred before 4 months of age. Witnessed deaths most commonly occurred at <1 month of age (28%), whereas unwitnessed deaths most commonly occurred at ages 2 to 3 months (44%) Among all U-NUSF, 69% occurred in the infant's home (62% witnessed, 77% unwitnessed). All unwitnessed deaths occurred in a crib; most witnessed deaths occurred while being held (54%) or in a car seat traveling (18%). Most infants (84%) had no history of abuse or neglect. Abnormal autopsy findings were reported in 46% of deaths (49% witnessed, 42% unwitnessed).

CONCLUSIONS

Characterizing these deaths is key to advancing our knowledge of SUID etiology. Our study revealed a heterogeneous group of infants, suggesting physiologic, genetic, or environmental etiologies.

Safe sleep practices for infants: Comprehensive analysis of YouTube videos

AIM

This study aimed to analyze the accuracy, quality, and reliability of the content of YouTube videos on safe sleep for infants in relation to the safe sleep recommendations from the American Academy of Pediatrics (AAP).

METHODS

The research was conducted by searching the video-sharing platform YouTube for the keywords "safe sleep." The videos were subjected to a review and evaluation process conducted by two independent reviewers. The modified DISCERN and Global Quality Scale (GQS) were employed to assess the quality and reliability of the videos. The content of the videos was evaluated using an eight-item checklist prepared by the researchers in accordance with the recommendations of the AAP. The Kruskal-Wallis-H, Mann-Whitney U, and Pearson correlation analyses were employed for the purpose of data analysis. All statistical data were deemed significant at the 0.05 level.

RESULTS

The 100 most relevant videos were viewed, and 85 videos that met the inclusion criteria were subjected to analysis. The mean values for the quality and reliability of the videos are 2.98 for the modified DISCERN score and 3.26 for the GQS. The mean value for the total checklist score was 4.78 out of 8. As indicated by the checklist developed in this study for the assessment of safe sleep video content, four of the eight items were present in over 80 % of the videos. The remaining four items were present in less than 42 % of the videos. A strong correlation was observed between the total score on the checklist and the modified DISCERN score (r = 0.915, p < 0.001) and the GQS (r = 0.918, p < 0.001).

CONCLUSION

The evidence presented in this study indicates that improvements are needed in the quality and reliability of content on safe sleep practices for infants on YouTube.

[Smoking cessation during pregnancy]

Smoking during pregnancy is associated with negative pregnancy and perinatal health outcomes. Physiological and societal particularities can modify the smoking behavior of pregnant women. Pregnancy is a teachable moment for smoking cessation. Increased nicotine clearance may lead to exacerbated tobacco withdrawal symptoms and desire to smoke, which need to be taken into account when helping pregnant smokers to quit. Although most pregnant smokers try to quit on their own, 12% of pregnant women in France reported smoking in 2021 during the 3rd trimester of pregnancy. Health care professionals should screen for tobacco consumption and assess the level of addiction. Management of smoking cessation can be multidisciplinary, including non-pharmacological support such as counselling, behavioral support, financial reward contingent on abstinence, and medication (nicotine replacement therapies). Assessment and limitation of secondhand smoke exposure (SHS) is needed because SHS can also have negative maternal and fetal consequences. Management of relapse during the postpartum period is also to be anticipated; in 2021, it concerned 22.4% of women who had stopped smoking during pregnancy. While electronic cigarette use is increasing overall and among pregnant women who smoke (5.4 before pregnancy, 1.3% during the 3rd trimester in 2021), well-conducted smoking cessation studies are necessary to assess its benefits and potential risks in this specific group of smokers.

The double-edged nature of nicotine: toxicities and therapeutic potentials

Nicotine is the primary addictive component of cigarette smoke and is associated with various smoking-related diseases. However, recent research has revealed its broader cognitive-enhancing and anti-inflammatory properties, suggesting its potential therapeutic applications in several conditions. This review aims to examine the double-edged nature of nicotine, encompassing its positive and negative effects. We provide a concise overview of the physiochemical properties and pharmacology of nicotine, including insights into nicotine receptors. Therefore, the article is divided into two main sections: toxicity and therapeutic potential. We comprehensively explored nicotine-related diseases, focusing on specific signaling pathways and the underlying mechanisms that contribute to its effects. Furthermore, we addressed the current research challenges and future development perspectives. This review aims to inspire future researchers to explore the full medical potential of nicotine, which holds significant promise for the clinical management of specific diseases.

Death from Failed Protection? An Evolutionary-Developmental Theory of Sudden Infant Death Syndrome

Sudden infant death syndrome (SIDS) has been mainly described from a risk perspective, with a focus on endogenous, exogenous, and temporal risk factors that can interact to facilitate lethal outcomes. Here we discuss the limitations that this risk-based paradigm may have, using two of the major risk factors for SIDS, prone sleep position and bed-sharing, as examples. Based on a multipronged theoretical model encompassing evolutionary theory, developmental biology, and cultural mismatch theory, we conceptualize the vulnerability to SIDS as an imbalance between current physiologic-regulatory demands and current protective abilities on the part of the infant. From this understanding, SIDS appears as a developmental condition in which competencies relevant to self-protection fail to develop appropriately in the future victims. Since all of the protective resources in question are bound to emerge during normal infant development, we contend that SIDS may reflect an evolutionary mismatch situation-a constellation in which certain modern developmental influences may overextend the child's adaptive (evolutionary) repertoire. We thus argue that SIDS may be better understood if the focus on risk factors is complemented by a deeper appreciation of the protective resources that human infants acquire during their normal development. We extensively analyze this evolutionary-developmental theory against the body of epidemiological and experimental evidence in SIDS research and thereby also address the as-of-yet unresolved question of why breastfeeding may be protective against SIDS.

Heatwaves and wildfires suffocate our healthy start to life: time to assess impact and take action

Adverse environmental exposures in utero and early childhood are known to programme long-term health. Climate change, by contributing to severe heatwaves, wildfires, and other natural disasters, is plausibly associated with adverse pregnancy outcomes and an increase in the future burden of chronic diseases in both mothers and their babies. In this Personal View, we highlight the limitations of existing evidence, specifically on the effects of severe heatwave and wildfire events, and compounding syndemic events such as the COVID-19 pandemic, on the short-term and long-term physical and mental health of pregnant women and their babies, taking into account the interactions with individual and community vulnerabilities. We highlight a need for an international, interdisciplinary collaborative effort to systematically study the effects of severe climate-related environmental crises on maternal and child health. This will enable informed changes to public health policy and clinical practice necessary to safeguard the health and wellbeing of current and future generations.

Qualitative assessment of infant sleep practices and other risk factors of sudden infant death syndrome (SIDS) among mothers in Lusaka, Zambia

BACKGROUND

There is very little information on the beliefs and perceptions of mothers about SIDS and its related risk factors in Africa. To better understand parental decisions about infant sleep practices and other risk factors for SIDS, we conducted focus group discussions (FGDs) with mothers of infants in Lusaka, Zambia.

METHODS

FGDs involved 35 purposively sampled mothers aged 18-49 years. FGDs were conducted using a semi-structured interview guide in the local language, Nyanja. These were translated, transcribed verbatim into English, and then coded and analyzed using thematic analysis in NVivo 12.

RESULTS

Six FGDs were conducted with 35 mothers in April-May 2021 across two study sites. FGD Participants were generally aware of sudden unexplained infant deaths, with several describing stories of apparent SIDS in the community. The side sleeping position was preferred and perceived to be safer for the infant with most believing the supine position posed an aspiration or choking risk to the infant. Bedsharing was also preferred and perceived to be convenient for breastfeeding and monitoring of the infant. Experienced family members such as grandmothers and mothers-in-law, and health care workers were frequently cited as sources of information on infant sleep position. A heightened awareness of the infant's sleeping environment was suggested as a mechanism to prevent SIDS and smothering.

CONCLUSIONS

Decisions about bedsharing and infant sleep position were guided by maternal beliefs and perceptions about what is convenient for breastfeeding and safer for the infant. These concerns are vital to designing tailored interventions to address sleep-related sudden infant losses in Zambia. Public health campaigns with tailored messages that address these concerns are likely to be effective at ensuring optimal uptake of safe sleep recommendations.

Evidence Base for 2022 Updated Recommendations for a Safe Infant Sleeping Environment to Reduce the Risk of Sleep-Related Infant Deaths

Every year in the United States, approximately 3500 infants die of sleep-related infant deaths, including sudden infant death syndrome (SIDS) (International Statistical Classification of Diseases and Related Health Problems 10th Revision [ICD-10] R95), ill-defined deaths (ICD-10 R99), and accidental suffocation and strangulation in bed (ICD-10 W75). After a substantial decline in sleep-related deaths in the 1990s, the overall death rate attributable to sleep-related infant deaths have remained stagnant since 2000, and disparities persist. The triple risk model proposes that SIDS occurs when an infant with intrinsic vulnerability (often manifested by impaired arousal, cardiorespiratory, and/or autonomic responses) undergoes an exogenous trigger event (eg, exposure to an unsafe sleeping environment) during a critical developmental period. The American Academy of Pediatrics recommends a safe sleep environment to reduce the risk of all sleep-related deaths. This includes supine positioning; use of a firm, noninclined sleep surface; room sharing without bed sharing; and avoidance of soft bedding and overheating. Additional recommendations for SIDS risk reduction include human milk feeding; avoidance of exposure to nicotine, alcohol, marijuana, opioids, and illicit drugs; routine immunization; and use of a pacifier. New recommendations are presented regarding noninclined sleep surfaces, short-term emergency sleep locations, use of cardboard boxes as a sleep location, bed sharing, substance use, home cardiorespiratory monitors, and tummy time. In addition, additional information to assist parents, physicians, and nonphysician clinicians in assessing the risk of specific bed-sharing situations is included. The recommendations and strength of evidence for each recommendation are published in the accompanying policy statement, which is included in this issue.

Unique effects of nicotine across the lifespan

Smoking remains the leading cause of preventable death in the United States. Although combustible cigarettes are largely being replaced by tobacco-free products, nicotine use continues to increase in vulnerable populations, including youth, adolescents, and pregnant women. Nicotine exerts unique effects on specific brain regions during distinct developmental periods due to the dynamic expression of nicotinic acetylcholine receptors (nAChRs) throughout the lifespan. Nicotine exposure is a health concern not only for adults but also has neurotoxic effects on the fetus, newborn, child, and adolescent. In this review, we aim to highlight the dynamic roles of nAChRs throughout gestation, adolescence, and adulthood. We also provide clinical and preclinical evidence of the neurodevelopmental, cognitive, and behavioral consequences of nicotine exposure at different developmental periods. This comprehensive review highlights unique effects of nicotine throughout the lifespan to help elucidate interventions and public health measures to protect sensitive populations from nicotine exposure.

A systematic review of the burden and risk factors of sudden infant death syndrome (SIDS) in Africa

Background

While sudden infant death syndrome (SIDS) has long been recognized as a leading preventable cause of infant mortality in high-income countries, little is known about the burden of SIDS in Africa. To address this knowledge gap, we conducted the first systematic review of SIDS-related publications in Africa. Our objective was to assess the prevalence of SIDS and its risk factors in Africa.

Methods

We systematically searched PubMed, Embase, Web of Science, Cochrane, and Google Scholar to identify studies published until December 26, 2020. Review authors screened titles and abstracts, and selected articles independently for full-text review. Risk of bias was assessed using the Newcastle Ottawa Scale (NOS) or a modification. Data on the proportion of infants who died of SIDS and reported prevalence of any risk factors were extracted using customized data extraction forms in Covidence.

Results

Our analysis rested on 32 peer-reviewed articles. Nine studies presented prevalence estimates on bedsharing and prone sleeping, suggesting near-universal bedsharing of infants with parents (range, 60 to 91.8%) and frequent use of the prone sleeping position (range, 26.7 to 63.8%). Eleven studies reported on the prevalence of SIDS, suggesting high rates of SIDS in Africa. The prevalence of SIDS ranged from 3.7 per 1000 live births in South Africa, 2.5 per 1000 live births in Niger, and 0.2 per 1000 live births in Zimbabwe. SIDS and other sudden infant deaths accounted for between 2.5 to 21% of infant deaths in South Africa and 11.3% in Zambia.

Conclusions

Africa may have the highest global rate of SIDS with a high burden of associated risk factors. However, majority of the studies were from South Africa which limits generalizability of our findings to the entire continent. There is an urgent need for higher quality studies outside of South Africa to fill this knowledge gap.

Protocol registration

Prospero Registration Number: CRD42021257261

Maternal Smoking, Alcohol and Recreational Drug Use and the Risk of SIDS Among a US Urban Black Population

BACKGROUND

Rates of sudden infant death syndrome (SIDS) are twice as high among Black infants compared to white infants in the US. While the contribution of sleep environment factors to this disparity is known, little is known about the risk of SIDS among Black infants in relation to maternal prenatal smoking, alcohol and drug use as well as infant smoke exposure.

OBJECTIVE

To assess the contribution of maternal substance use during pregnancy and the potential interactions with infant bedsharing in a high-risk, urban Black population.

METHODS

The Chicago Infant Mortality Study (CIMS) collected data on 195 Black infants who died of SIDS and 195 controls matched on race, age and birthweight. Risk of SIDS was calculated for maternal smoking, alcohol and drug use, adjusting for potential confounding variables and other risk factors for SIDS. Interactions between these substance use variables and bedsharing were also calculated.

RESULTS

Infants were more likely to die from SIDS if the mother smoked during pregnancy (aOR 3.90, 95% CI 1.37-3.30) and post-pregnancy (aOR 2.49, 95% CI 1.49-4.19). There was a dose response seen between amount smoked during pregnancy and risk of SIDS. Use of alcohol (aOR 2.89, 95% CI 1.29-6.99), cocaine (aOR 4.78, 95% CI 2.45-9.82) and marijuana (aOR 2.76, 95% CI 1.28-5.93) were associated with increased risk of SIDS. In the final, multivariable model controlling for sociodemographic factors and covariates, maternal smoking (aOR 3.03, 95% CI 1.03-8.88) and cocaine use (aOR 4.65, 95% CI 1.02-21.3) during pregnancy remained significant. There were significant, positive interactions between bedsharing and maternal smoking during pregnancy and post-pregnancy, alcohol use and cocaine use.

CONCLUSION

Maternal use of tobacco, alcohol and cocaine during pregnancy is associated with significantly increased risk of SIDS in a Black, urban population. Reducing substance use and eliminating disparities in SIDS, sudden unexpected infant death (SUID) (also known as sudden unexpected death in infancy or SUDI) and infant mortality need to involve more than individual level education, but instead will require a comprehensive examination of the role of social determinants of health as well as a multi-pronged approach to address both maternal and infant health and wellbeing.

Altered Development of Mesencephalic Dopaminergic Neurons in SIDS: New Insights into Understanding Sudden Infant Death Pathogenesis

Sudden infant death syndrome (SIDS) is defined as the unexpected sudden death of an infant under 1 year of age that remains unexplained after a thorough case investigation. The SIDS pathogenesis is still unknown; however, abnormalities in brain centers that control breathing and arousal from sleep, including dramatic changes in neurotransmitter levels, have been supposed in these deaths. This is the first study focusing on mesencephalic dopaminergic neurons, so far extensively studied only in animals and human neurological diseases, in SIDS. Dopaminergic structures in midbrain sections of a large series of sudden infant deaths (36 SIDS and 26 controls) were identified using polyclonal rabbit antibodies against tyrosine hydroxylase, the rate-limiting enzyme in catecholamine biosynthesis, and the dopamine transporter, a membrane protein specifically expressed in dopaminergic cells. Dopamine-immunolabeled neurons were observed concentrated in two specific structures: the pars compacta of the substantia nigra and in the subnucleus medialis of the periaqueductal gray matter. Anatomical and functional degenerations of dopaminergic neurons in these regions were observed in most SIDS cases but never in controls. These results indicate that dopamine depletion, which is already known to be linked especially to Parkinson's disease, is strongly involved even in SIDS pathogenesis.

Smoke Exposure Disclosure: Parental Perspectives of Screening in the Inpatient Setting

OBJECTIVES

Current screening questions for pediatric tobacco smoke exposure are suboptimal. Factors influencing screening accuracy, particularly in the pediatric inpatient setting, are unknown. Our objective was to identify facilitators of and barriers to parental disclosure of smoke exposure when screened during their child's hospitalization and strategies to promote accurate disclosure.

METHODS

This qualitative study was conducted with a convenience sample of parents of children admitted to the medical and surgical unit of a Midwest tertiary care children's hospital. Eligible parents included those with documented disclosure of smoke exposure in the child's electronic health record. A researcher trained in qualitative methods conducted semistructured, in-depth interviews with parents regarding their experiences with smoke exposure screening in the inpatient pediatric setting. Two researchers independently identified concepts directed at barriers, facilitators, and strategies for effective screening, which were compared and reconciled by a third researcher.

RESULTS

Facilitators of disclosing their child's smoke exposure included the following: (1) the caregiver's internal characteristic(s) promoting disclosure, (2) perceived relevance of the screening question to the child's health, and (3) the questioner being viewed positively. Barriers included the following: (1) fear of negative consequences, (2) a vague question, (3) lack of knowledge, (4) guilt, and (5) unconducive environment and timing. The strategies parents suggested to improve screening for smoke exposure included the following: (1) communicate preemptively, (2) provide specific exposure examples, (3) improve questioner-caregiver rapport, and (4) improve screening environment and timing.

CONCLUSIONS

Parents identified various mechanisms to improve tobacco smoke exposure screening. The facilitators, barriers, and strategies provide opportunities to improve the inpatient pediatric screening process.

Tobacco use disorder and the lungs

This narrative review provides a summary of the impact of tobacco smoking on the respiratory system and the benefits of smoking cessation. Tobacco smoking is one of the leading preventable causes of death world-wide and a major risk factor for lung cancer and chronic obstructive pulmonary disease. Smoking is also associated with an increased risk of respiratory infections and appears to be related to poorer outcomes among those with COVID-19. Non-smokers with second-hand smoke exposure also experience significant adverse respiratory effects. Smoking imposes enormous health- and non-health-related costs to societies. The benefits of smoking cessation, in both prevention and management of respiratory disease, have been known for decades and, to this day, cessation support remains one of the most important cost-effective interventions that health professionals can provide to people who smoke. Cessation at any age confers substantial health benefits, even in smokers with established morbidities. As other treatments for chronic respiratory disease advance and survival rates increase, smoking cessation treatment will become even more relevant. While smoking cessation interventions are available, the offer of these by clinicians and uptake by patients remain limited.

The importance of non-coding RNAs in environmental stress-related developmental brain disorders: A systematic review of evidence associated with exposure to alcohol, anesthetic drugs, nicotine, and viral infections

Brain development is a dynamic and lengthy process that includes cell proliferation, migration, neurogenesis, gliogenesis, synaptogenesis, and pruning. Disruption of any of these developmental events can result in long-term outcomes ranging from brain structural changes, to cognitive and behavioral abnormality, with the mechanisms largely unknown. Emerging evidence suggests non-coding RNAs (ncRNAs) as pivotal molecules that participate in normal brain development and neurodevelopmental disorders. NcRNAs such as long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) are transcribed from the genome but not translated into proteins. Many ncRNAs have been implicated as tuners of cell fate. In this review, we started with an introduction of the current knowledge of lncRNAs and miRNAs, and their potential roles in brain development in health and disorders. We then reviewed and discussed the evidence of ncRNA involvement in abnormal brain development resulted from alcohol, anesthetic drugs, nicotine, and viral infections. The complex connections among these ncRNAs were also discussed, along with potential overlapping ncRNA mechanisms, possible pharmacological targets for therapeutic/neuroprotective interventions, and potential biomarkers for brain developmental disorders.

Prenatal nicotine exposure was associated with long-term impact on the cardiovascular system and regulation-Review

AIM

The aim of this structured review was to discuss knowledge of nicotine use during pregnancy and long-term effects on children's cardiovascular function.

METHODS

PubMed and MEDLINE were searched for original papers that covered various forms of nicotine exposure during pregnancy and this identified 314 papers published in English from inception of the databases to 1 March 2021. The research focus was prenatal exposure that had long-term effects on the cardiovascular system. The search was expanded from the reference list of the selected papers, which identified another 17 papers.

RESULTS

The 34 original papers that were included covered 172,696 subjects from foetuses to 19 years of age. Cardiovascular autonomic dysfunction was discussed in 12 of the papers and 16 studies reported on blood pressure. The remaining studies covered structural or functional changes in arterial wall or heart. There were convincing data on autonomic dysfunction and increased blood pressure. Some data were conflicting and problems with misclassification of exposure were evident.

CONCLUSION

Prenatal nicotine exposure was associated with long-term developmental changes in the cardiovascular system and regulation. There were no safe periods, doses or nicotine products during pregnancy and women should abstain when planning a pregnancy.

Implementation of Safe Sleep Practices by Mothers with 0-1 Year-Old Infants

Aim: The sleep environment of an infant affects the likelihood of sudden infant death syndrome and other sleep-related infant deaths. This study was performed to determine the safe sleep practices of mothers with 0–1 year-old infants. Methods: This descriptive study included 204 mothers with 0–1 year-old infants who visited family health centers between October 30 and December 28, 2018. The data were collected using a questionnaire form and evaluated using the number, percentage, mean, standard deviation, and chi-squared test. Results: The mean age of the mothers was 28.48 ±5.83 years; 43.1% were primary school graduates and 84.8% were housewives; 53.9% of the infants were girls and 39.2% were 0–3 months old. It was found that 47.5% of the mothers put their infant to sleep in the supine position, 46.1% in the non-supine position, 70.1% on a soft bed, and 76.5% by using a pillow. In addition, 41.2% of the mothers stated that they used pacifiers while putting their infant to sleep, 9.8% stated that they slept in the same bed with their infant, and 92.9% stated that they slept in the same room. Conclusion: It was determined that the mothers performed certain risky practices related to the sleep environment, particularly regarding soft beds’ use, sleeping positions, pillow use, and bed-sharing. It may be recommended that healthcare professionals play an active role and take responsibility in increasing the level of knowledge and awareness of parents regarding safe sleep. Keywords: sleep, infant, mothers, family practice

Environmental exposures and sleep outcomes: A review of evidence, potential mechanisms, and implications

Environmental exposures and poor sleep outcomes are known to have consequential effects on human health. This integrative review first seeks to present and synthesize existing literature investigating the relationship between exposure to various environmental factors and sleep health. We then present potential mechanisms of action as well as implications for policy and future research for each environmental exposure. Broadly, although studies are still emerging, empirical evidence has begun to show a positive association between adverse effects of heavy metal, noise pollution, light pollution, second-hand smoke, and air pollution exposures and various sleep problems. Specifically, these negative sleep outcomes range from subjective sleep manifestations, such as general sleep quality, sleep duration, daytime dysfunction, and daytime sleepiness, as well as objective sleep measures, including difficulties with sleep onset and maintenance, sleep stage or circadian rhythm interference, sleep arousal, REM activity, and sleep disordered breathing. However, the association between light exposure and sleep is less clear. Potential toxicological mechanisms are thought to include the direct effect of various environmental toxicants on the nervous, respiratory, and cardiovascular systems, oxidative stress, and inflammation. Nevertheless, future research is required to tease out the exact pathways of action to explain the associations between each environmental factor and sleep, to inform possible therapies to negate the detrimental effects, and to increase efforts in decreasing exposure to these harmful environmental factors to improve health.

Circadian variation in sudden unexpected infant death in the United States

Aim

To determine which factors are associated with sudden unexpected infant death (SUID) by time of day.

Methods

Data were analysed from the National Fatality Review Case Reporting System (2006‐2015). Out of 20 005 SUID deaths in 37 states, 12 191 (60.9%) deaths had a recorded nearest hour of discovery of the infant. We compared distribution patterns between time of death and 118 variables to determine which were significantly correlated with SUID time of death using advanced statistical modelling techniques.

Results

The 12‐hour time periods that were most different were 10:00 to 21:00 (daytime) and 22:00 to 09:00 (nighttime). The main features that were associated with nighttime SUID were bed sharing, younger infants, non‐white infants, placed supine to sleep and found supine, and caregiver was the parent. Daytime SUID was associated with older infants, day care, white infants, sleeping in an adult bed and prone sleep position. Factors not associated with time of death were sex of the infant, smoking and breastfeeding.

Conclusion

Sudden unexpected infant death deaths that occur at night are associated with a separate set of risk factors compared to deaths that occur during the day. However, to minimise risk, it is important to practice safe sleep guidelines during both nighttime and daytime sleep.

Health outcomes of smoking during pregnancy and the postpartum period: an umbrella review

BACKGROUND

Smoking during pregnancy (SDP) and the postpartum period has serious health outcomes for the mother and infant. Although some systematic reviews have shown the impact of maternal SDP on particular conditions, a systematic review examining the overall health outcomes has not been published. Hence, this paper aimed to conduct an umbrella review on this issue.

METHODS

A systematic review of systematic reviews (umbrella review) was conducted according to a protocol submitted to PROSPERO ( CRD42018086350 ). CINAHL, EMBASE, MEDLINE, PsycINFO, Web of Science, CRD Database and HMIC databases were searched to include all studies published in English by 31 December 2017, except those focusing exclusively on low-income countries. Two researchers conducted the study selection and quality assessment independently.

RESULTS

The review included 64 studies analysing the relationship between maternal SDP and 46 health conditions. The highest increase in risks was found for sudden infant death syndrome, asthma, stillbirth, low birth weight and obesity amongst infants. The impact of SDP was associated with the number of cigarettes consumed. According to the causal link analysis, five mother-related and ten infant-related conditions had a causal link with SDP. In addition, some studies reported protective impacts of SDP on pre-eclampsia, hyperemesis gravidarum and skin defects on infants. The review identified important gaps in the literature regarding the dose-response association, exposure window, postnatal smoking.

CONCLUSIONS

The review shows that maternal SDP is not only associated with short-term health conditions (e.g. preterm birth, oral clefts) but also some which can have life-long detrimental impacts (e.g. obesity, intellectual impairment).

IMPLICATIONS

This umbrella review provides a comprehensive analysis of the overall health impacts of SDP. The study findings indicate that while estimating health and cost outcomes of SDP, long-term health impacts should be considered as well as short-term effects since studies not including the long-term outcomes would underestimate the magnitude of the issue. Also, interventions for pregnant women who smoke should consider the impact of reducing smoking due to health benefits on mothers and infants, and not solely cessation.

Nicotinic Receptors in the Brainstem Ascending Arousal System in SIDS With Analysis of Pre-natal Exposures to Maternal Smoking and Alcohol in High-Risk Populations of the Safe Passage Study

Pre-natal exposures to nicotine and alcohol are known risk factors for sudden infant death syndrome (SIDS), the leading cause of post-neonatal infant mortality. Here, we present data on nicotinic receptor binding, as determined by 125I-epibatidine receptor autoradiography, in the brainstems of infants dying of SIDS and of other known causes of death collected from the Safe Passage Study, a prospective, multicenter study with clinical sites in Cape Town, South Africa and 5 United States sites, including 2 American Indian Reservations. We examined 15 pons and medulla regions related to cardiovascular control and arousal in infants dying of SIDS (n = 12) and infants dying from known causes (n = 20, 10 pre-discharge from time of birth, 10 post-discharge). Overall, there was a developmental decrease in 125I-epibatidine binding with increasing postconceptional age in 5 medullary sites [raphe obscurus, gigantocellularis, paragigantocellularis, centralis, and dorsal accessory olive (p = 0.0002-0.03)], three of which are nuclei containing serotonin cells. Comparing SIDS with post-discharge known cause of death (post-KCOD) controls, we found significant decreased binding in SIDS in the nucleus pontis oralis (p = 0.02), a critical component of the cholinergic ascending arousal system of the rostral pons (post-KCOD, 12.1 ± 0.9 fmol/mg and SIDS, 9.1 ± 0.78 fmol/mg). In addition, we found an effect of maternal smoking in SIDS (n = 11) combined with post-KCOD controls (n = 8) on the raphe obscurus (p = 0.01), gigantocellularis (p = 0.02), and the paragigantocellularis (p = 0.002), three medullary sites found in this study to have decreased binding with age and found in previous studies to have abnormal indices of serotonin neurotransmission in SIDS infants. At these sites, 125I-epibatidine binding increased with increasing cigarettes per week. We found no effect of maternal drinking on 125I-epibatidine binding at any site measured. Taken together, these data support changes in nicotinic receptor binding related to development, cause of death, and exposure to maternal cigarette smoking. These data present new evidence in a prospective study supporting the roles of developmental factors, as well as adverse exposure on nicotinic receptors, in serotonergic nuclei of the rostral medulla-a finding that highlights the interwoven and complex relationship between acetylcholine (via nicotinic receptors) and serotonergic neurotransmission in the medulla.

Sudden Infant Death Syndrome: Beyond Risk Factors

Sudden infant death syndrome (SIDS) is defined as "the sudden death of an infant under 1 year of age which remains unexplained after thorough investigation including a complete autopsy, death scene investigation, and detailed clinical and pathological review". A significant decrease of SIDS deaths occurred in the last decades in most countries after the beginning of national campaigns, mainly as a consequence of the implementation of risk reduction action mostly concentrating on the improvement of sleep conditions. Nevertheless, infant mortality from SIDS still remains unacceptably high. There is an urgent need to get insight into previously unexplored aspects of the brain system with a special focus on high-risk groups. SIDS pathogenesis is associated with a multifactorial condition that comprehends genetic, environmental and sociocultural factors. Effective prevention of SIDS requires multiple interventions from different fields. Developing brain susceptibility, intrinsic vulnerability and early identification of infants with high risk of SIDS represents a challenge. Progress in SIDS research appears to be fundamental to the ultimate aim of eradicating SIDS deaths. A complex model that combines different risk factor data from biomarkers and omic analysis may represent a tool to identify a SIDS risk profile in newborn settings. If high risk is detected, the infant may be referred for further investigations and follow ups. This review aims to illustrate the most recent discoveries from different fields, analyzing the neuroanatomical, genetic, metabolic, proteomic, environmental and sociocultural aspects related to SIDS.

Decreasing smoking during pregnancy: Potential economic benefit of reducing sudden unexpected infant death

Sudden Unexpected Infant Death (SUID) remains the leading cause of death among U.S. infants age 1-12 months. Extensive epidemiological evidence documents maternal prenatal cigarette smoking as a major risk factor for SUID, but leaves unclear whether quitting reduces risk. This Commentary draws attention to a report by Anderson et al. (Pediatrics. 2019, 143[4]) that represents a breakthrough on this question and uses their data on SUID risk reduction to delineate potential economic benefits. Using a five-year (2007-11) U.S. CDC Birth Cohort Linked Birth/Infant Death dataset, Anderson et al. demonstrated that compared to those who continued smoking, women who quit or reduced smoking by third trimester decreased the adjusted odds of SUID risk by 23% (95% CI, 13%-33%) and 12% (95% CI, 2%-21%), respectively. We applied these reductions to the U.S. Department of Health and Human Services' recommended value of a statistical life in 2020 ($10.1 million). Compared to continued smoking during pregnancy, the economic benefits per woman of quitting or reducing smoking are $4700 (95% CI $2700-$6800) and $2500 (95% CI, $400-$4300), respectively. While the U.S. obtained aggregate annual economic benefits of $0.58 (95% CI, 0.35-0.82) billion from pregnant women who quit or reduced smoking, it missed an additional $1.16 (95%CI 0.71-1.60) billion from the women who continued smoking. Delineating the health and economic impacts of decreasing smoking during pregnancy using large epidemiological studies like Anderson et al. is critically important for conducting meaningful economic analyses of the benefits-costs of developing more effective interventions for decreasing smoking during pregnancy.

The Role of Maternal Smoking in Sudden Fetal and Infant Death Pathogenesis

Maternal smoking is a risk factor for both sudden infant death syndrome (SIDS) and sudden intrauterine unexplained death syndrome (SIUDS). Both SIDS and SIUDS are more frequently observed in infants of smoking mothers. The global prevalence of smoking during pregnancy is 1.7% and up to 8.1% of women in Europe smoke during pregnancy and worldwide 250 million women smoke during pregnancy. Infants born to mothers who smoke have an abnormal response to hypoxia and hypercarbia and they also have reduced arousal responses. The harmful effects of tobacco smoke are mainly mediated by release of carbon monoxide and nicotine. Nicotine can enter the fetal circulation and affect multiple developing organs including the lungs, adrenal glands and the brain. Abnormalities in brainstem nuclei crucial to respiratory control, the cerebral cortex and the autonomic nervous system have been demonstrated. In addition, hypodevelopment of the intermediolateral nucleus in the spinal cord has been reported. It initiates episodic respiratory movements that facilitate lung development. Furthermore, abnormal maturation and transmitter levels in the carotid bodies have been described which would make infants more vulnerable to hypoxic challenges. Unfortunately, smoking cessation programs do not appear to have significantly reduced the number of pregnant women who smoke.

Secondhand Smoke Risk Communication: Effects on Parent Smokers' Perceptions and Intentions

This study examined effective strategies to communicate with parent smokers about the risks of secondhand smoke (SHS) exposure to children. An online, between-subjects experimental survey was administered via TurkPrime Panels to recruit participants (N = 623) comprising adult smokers living with children (aged 0-15). Participants were assigned to messages conditions that differed by message recommendation (cessation; cessation+exposure reduction) and format (video; text-only) or to a no-message control. Participants in a message condition viewed a message, and all participants responded to questions about their perceptions and intentions. Parent smokers who viewed either message recommendation reported greater harm perceptions (p <.001), self-efficacy (p <.001), and help-seeking intentions (p <.05) than the no-message control group. Cessation+exposure reduction recommendations elicited greater quit intentions than the no-message control (p <.05). Compared to text-only, videos elicited greater reduce-exposure intentions (p <.05) and interpersonal communication intentions (p <.05). Only videos elicited greater quit intentions (p <.01) and help-seeking intentions (p <.01) than the no-message control. Communication about this topic can be optimized by recommending both cessation and exposure-reduction behaviors (versus cessation only), and by using videos (versus traditional print/text-based materials).

[Smoking and Breastfeeding - CNGOF-SFT Expert Report and Guidelines on the management for Smoking Management During Pregnancy]

INTRODUCTION

The consequences of smoking have been studied more during pregnancy than during breastfeeding. There is a passage of nicotine and other substances in breast milk and some modifications of milk composition. The objectives of this chapter are to study the benefits of breastfeeding in women who smoke, and the adaptation of smoking, medication and behavioral habits in case of incomplete withdrawal to better guide women.

METHODS

The Medline database, the Cochrane Library and foreign guidelines from 1999 to 2019 have been consulted.

RESULTS

The conservation of the benefit of breastfeeding in smokers with regard to the prevention of respiratory infections, infantile colic, cognitive deficits, obesity, sudden infant death, is not known to date. It is therefore not recommended to include smoking status in the choice of feeding mode for the newborn (professional agreement). However, since breastfeeding is a factor associated with a reduction in smoking and/or withdrawal (NP2), it is recommended to promote breastfeeding in non-weaned women in order to limit smoking (grade B). The use of nicotine replacement therapy is possible during breastfeeding (professional agreement). In the absence of data, bupropion (Zyban®) and varenicline (Champix®) are not recommended for women who are breastfeeding (professional agreement). A free interval between smoking and breastfeeding reduces the concentration of nicotine in milk (NP4). For non-weaned women who are breastfeeding, it is therefore recommended not to smoke just before breastfeeding (professional agreement).

CONCLUSION

The results indicate that breastfeeding is possible in smokers, although less often initiated by them. If the conservation of its benefits for the child is not demonstrated to date, breastfeeding allows the mother to limit smoking.

[In Utero Exposure to Maternal Smoking: Impact on the Child from Birth to Adulthood - CNGOF-SFT Expert Report and Guidelines for Smoking Management during Pregnancy]

INTRODUCTION

Smoking during pregnancy leads to fetal passive smoking. It is associated with several obstetrical complications and is a major modifiable factor of maternal and fetal morbidity. Long-term consequences also exist but are less well known to health professionals and in the general population.

METHODS

Consultation of the Medline® database.

RESULTS

Maternal smoking during pregnancy is associated in the offspring with sudden infant death syndrome (NP2), impaired lung function (NP2), lower respiratory infections and asthma (NP2), overweight and obesity (NP2), cancers (NP3), risk of tobacco use, nicotine dependence and early smoking initiation (NP2). Unadjusted analyses show associations between in utero tobacco exposure and cognitive deficits (NP3), impaired school performance (NP3) and behavioral disorders in children (NP2), which are in a large part explained by environmental factors. There is a cross-generational effect of smoking during pregnancy. For example, an increased risk of asthma is observed in the grandchildren of smoking women (NP4). The respective roles of ante- and post-natal smoking remain difficult to assess.

CONCLUSION

These results highlight the importance of prevention measures against tobacco use in the general population, as well as screening measures and support for smoking cessation before or at the beginning of the pregnancy.

Modeling Healthcare Costs Attributable to Secondhand Smoke Exposure at Home among South Korean Children

Children exposed to secondhand smoke (SHS) are at increased risk for disease. We sought to estimate the medical costs among Korean children who were exposed to SHS at home. A Markov model was developed, including five diseases (asthma, acute otitis media, acute bronchitis, pneumonia and sudden infant death syndrome) that were significantly associated with SHS in children based on a systematic review. The time horizon of the analysis was 20 years (from birth to adulthood), and the cycle length was 1 week. The direct healthcare costs were discounted annually at 5%. Univariate and probabilistic sensitivity analyses were conducted. The Markov model estimated the healthcare costs for 20 years as 659.61 USD per exposed child, an increase of approximately 30% compared to the cost per unexposed child (507.32 USD). Sensitivity analysis suggested that the younger the age of the exposure, the greater the incremental healthcare costs incurred, implying that infants and young children were especially vulnerable to the SHS exposure. Findings of this study could provide key baseline data for future economic evaluations on SHS control policies in South Korea.

Obstetricians' and Gynecologists' Communication Practices around Smoking Cessation in Pregnancy, Secondhand Smoke and Sudden Infant Death Syndrome (SIDS): A Survey

Secondhand smoke (SHS) is a potential direct cause of Sudden Infant Death Syndrome (SIDS) among infants. Disparities in SHS exposure and SIDS deaths may be due to inconsistent communication among practitioners about SHS/SIDS risks. In order to assess current SHS/SIDS risks and communication practices and to identify areas of improvement, we conducted a survey of 316 obstetricians and gynecologists (ob/gyns) about the length of time spent having discussions, supplemental materials used, risks covered, cessation, and frequency of discussions. Most (55.3%) reported spending 1-4 min discussing risks/cessation. Nearly a third reported not using any supplemental materials; few used apps (4.4%) or videos (1.9%). Assisting patients with steps toward cessation was infrequent. Few ob/gyns had discussions with patients immediately postpartum. Only 51.9% strongly agreed that they felt sufficiently informed about SHS/SIDS risks to educate their patients. The communication by ob/gyns of SHS/SIDS risk varies greatly and presents opportunities for improvement. Each additional minute spent having discussions and the use of supplemental materials, such as apps, may improve communication effectiveness. The discussion of smoking behaviors immediately postpartum may help to prevent smoker relapse. An increased awareness of statewide cessation resources by ob/gyns is needed to assist patients with cessation. The development of standardized risk messaging may reduce the variation in communication practices among ob/gyns.

Implementation of a Statewide Program to Promote Safe Sleep, Breastfeeding and Tobacco Cessation to High Risk Pregnant Women

Infant mortality remains a problem in the United States with sleep-related deaths accounting for a significant portion. Known risk reduction strategies include breastfeeding, avoiding tobacco use and following the American Academy of Pediatrics' safe sleep guidelines. The purpose of this project was to evaluate outcomes of Safe Sleep Instructor-led community baby showers, which included safe sleep promotion, breastfeeding promotion and tobacco cessation education. Certified Safe Sleep Instructors (n = 35) were trained on how to plan and host a Community Baby Shower to provide education to pregnant women of low socioeconomic status or with high risk of infant mortality. Eighteen Community Baby Showers were held across two urban and eight rural counties in Kansas. Surveys were administered pre- and post-event to assess participant knowledge, confidence and intentions to follow through with planned action related to safe sleep, breastfeeding and reducing tobacco risk. Matched data were summarized and evaluated for differences using McNemar's and Wilcoxon Signed Rank tests. Significant increases were observed in Baby Shower participants' (n = 845) reported plans to follow the AAP Safe Sleep guidelines (all p < 0.001), likelihood to breastfeed (p < 0.001), confidence in ability to breastfeed for more than 6 months (p < 0.001), knowledge of local breastfeeding support resources (p < 0.001), knowledge of ways to avoid second-hand smoke exposure (p < 0.001) and knowledge of local tobacco cessation services (p = 0.004). Based on the result of the pre- and post-event surveys, certified Safe Sleep Instructors were able to plan and host successful events to increase knowledge and confidence related to risk reduction strategies to reduce sleep-related infant deaths.

Environmental Tobacco Smoke During the Early Postnatal Period of Mice Interferes With Brain 18 F-FDG Uptake From Infancy to Early Adulthood - A Longitudinal Study

Exposure to environmental tobacco smoke (ETS) is associated with high morbidity and mortality, mainly in childhood. Our aim was to evaluate the effects of postnatal ETS exposure in the brain 2-deoxy-2-[¹⁸F]-fluoro-D-glucose (¹⁸F-FDG) uptake of mice by positron emission tomography (PET) neuroimaging in a longitudinal study. C57BL/6J mice were exposed to ETS that was generated from 3R4F cigarettes from postnatal day 3 (P3) to P14. PET analyses were performed in male and female mice during infancy (P15), adolescence (P35), and adulthood (P65). We observed that ETS exposure decreased ¹⁸F-FDG uptake in the whole brain, both left and right hemispheres, and frontal cortex in both male and female infant mice, while female infant mice exposed to ETS showed decreased ¹⁸F-FDG uptake in the cerebellum. In addition, all mice showed reduced ¹⁸F-FDG uptake in infancy, compared to adulthood in all analyzed VOIs. In adulthood, ETS exposure during the early postnatal period decreased brain ¹⁸F-FDG uptake in adult male mice in the cortex, striatum, hippocampus, cingulate cortex, and thalamus when compared to control group. ETS induced an increase in ¹⁸F-FDG uptake in adult female mice when compared to control group in the brainstem and cingulate cortex. Moreover, male ETS-exposed animals showed decreased ¹⁸F-FDG uptake when compared to female ETS-exposed in the whole brain, brainstem, cortex, left amygdala, striatum, hippocampus, cingulate cortex, basal forebrain and septum, thalamus, hypothalamus, and midbrain. The present study shows that several brain regions are vulnerable to ETS exposure during the early postnatal period and these effects on ¹⁸F-FDG uptake are observed even a long time after the last exposure. This study corroborates our previous findings, strengthening the idea that exposure to tobacco smoke in a critical period interferes with brain development of mice from late infancy to early adulthood.

Primary Care Healthcare Professionals' Knowledge, Attitudes, and Practices Towards Promoting the Reduction of Children's Secondhand Smoke Exposure: A Mixed-Methods Review and Synthesis

INTRODUCTION

Secondhand smoke exposure (SHSe) leads to increased mortality and morbidity. Primary care healthcare professionals (HCPs) are well placed to support patients to reduce SHSe. This paper explores HCPs': (1) knowledge around SHSe; (2) current practices to promote SHSe reduction; (3) beliefs and experiences regarding delivering interventions to reduce SHSe; and (4) identified factors that influence the delivery of SHSe-related interventions.

METHODS

Six electronic databases were searched for relevant literature published January 1980-February 2016. 17 quantitative and 3 qualitative studies were included in this mixed-methods review. Data synthesis followed the method outlined by the Joanna Briggs Institute. This segregated approach involved independent syntheses of the quantitative and qualitative data followed by an overall mixed-methods synthesis.

RESULTS

Primary care HCPs had a basic understanding of the risks associated with SHSe but required training to help them intervene. It was more common for HCPs to ask about SHSe or provide advice than to act to facilitate SHSe reduction. SHSe was viewed as an issue of high importance and considered relevant to the role of the primary care HCPs. However, barriers such as the priority given to the issue and the desire to protect the professional relationship with patients prevented HCPs from intervening around SHSe.

CONCLUSIONS

Primary care HCPs require training, guidance, and support to enable them to intervene and support patients to effectively reduce SHSe.

IMPLICATIONS

This review used rigorous methods to explore the current, global literature on how children's exposure to secondhand smoke is being addressed in primary care settings. The review findings highlight healthcare professionals' need for further training and support, which would enable them to better translate their knowledge of the risks associated with secondhand smoke exposure into actual clinical practices. The review identified a lack of practical action taken to address secondhand smoke exposure, even once it has been identified as an issue.

Premature birth, homeostatic plasticity and respiratory consequences of inflammation

Infants who are born premature can have persistent apnea beyond term gestation, reemergence of apnea associated with inflammation during infancy, increased risk of sudden unexplained death, and sleep disorder breathing during infancy and childhood. The autonomic nervous system, particularly the central neural networks that control breathing and peripheral and central chemoreceptors and mechanoreceptors that modulate the activity of the central respiratory network, are rapidly developing during the last trimester (22-37 weeks gestation) of fetal life. With advances in neonatology, in well-resourced, developed countries, infants born as young as 23 weeks gestation can survive. Thus, a substantial part of maturation of central and peripheral systems that control breathing occurs ex-utero in infants born at the limit of viability. The balance of excitatory and inhibitory influences dictates the ultimate output from the central respiratory network. We propose in this review that simply being born early in the last trimester can trigger homeostatic plasticity within the respiratory network tipping the balance toward inhibition that persists in infancy. We discuss the intersection of premature birth, homeostatic plasticity and biological mechanisms leading to respiratory depression during inflammation in former premature infants.

Monitoring of Chemical Risk Factors for Sudden Infant Death Syndrome (SIDS) by Hydroxyapatite-Graphene-MWCNT Composite-Based Sensors

Sensing properties of chemical sensors based on ternary hydroxyapatite-graphene-multiwalled carbon nanotube (HA-GN-MWCNT) nanocomposite in the detection of chemical substances representing risk factors for sudden infant death syndrome (SIDS), have been evaluated. Characterization data of the synthesized composite have shown that the graphene-MWCNT network serves as a matrix to uniformly disperse the hydroxyapatite nanoparticles and provide suitable electrical properties required for developing novel electrochemical and conductometric sensors. A HA-GN-MWCNT composite-modified glassy carbon electrode (HA-GN-MWCNT/GCE) has been fabricated and tested for the simultaneous monitoring of nicotine and caffeine by cyclic voltammetry (CV) and square wave voltammetry (SWV), whereas a HA-GN-MWCNT conductive gas sensor has been tested for the detection of CO2 in ambient air. Reported results suggest that the synergic combination of the chemical properties of HA and electrical/electrochemical characteristics of the mixed graphene-MWCNT network play a prominent role in enhancing the electrochemical and gas sensing behavior of the ternary HA-GN-MWCNT hybrid nanostructure. The high performances of the developed sensors make them suitable for monitoring unhealthy actions (e. g. smoking, drinking coffee) in breastfeeding women and environmental factors (bad air quality), which are associated with an enhanced risk for SIDS.

The 'Dangerous Cocktail': an epidemiological survey on the attitude of a population of pregnant women towards some pregnancy risk factors

Many investigations have shown the important role played by risk factors such as tobacco and alcohol and infectious agents (especially Rubella) in the development of congenital anomalies (CAs). Through the administration of a questionnaire, we evaluated the attitude of a population of pregnant women towards some risk factors in pregnancy (smoking and alcohol habit and risk of contracting one of TORCH agents). 14% of the women continued to smoke despite pregnancy; the majority of these were 34-35 years old, divorced, workers and with a high educational level. The 4.3% who identified as moderate drinkers; were mainly younger and married. Concerning the TORCH agents, it a high percentage were negative to the Rubella antibodies (62.8%). In order to improve the awareness of pregnant women on these risk factors, health education campaigns represent a public health cornerstone. Impact statementWhat is already known on this subject? Several investigations have shown an association between congenital anomalies (CAs) and various exogenous factors such as air pollutants, pesticides, metals, radiations and others present in the environmental matrices. Moreover, an important role is played by some risk factors linked to the lifestyles (i.e. tobacco and alcohol).What do the results of this study add? Our study shows that the awareness of the women about the importance of these risk factors is still rather poor, especially concerning the avoidable risks associated with smoke and alcohol and the preventable risk associated with rubella infection.What are the implications of these findings for clinical practice and/or further research? Our results highlight the importance of continuous health education both about the risk to smoke and drink during pregnancy and about the risk not to have had contract the rubella infection before the pregnancy. Particularly, about the latter issue, it appears necessary to increase the pre-conceptional diagnosis and, eventually, to vaccinate the women resulted negative in order to eliminate congenital rubella.

Maternal Smoking Before and During Pregnancy and the Risk of Sudden Unexpected Infant Death

OBJECTIVES

Maternal smoking during pregnancy is an established risk factor for sudden unexpected infant death (SUID). Here, we aim to investigate the effects of maternal prepregnancy smoking, reduction during pregnancy, and smoking during pregnancy on SUID rates.

METHODS

We analyzed the Centers for Disease Control and Prevention Birth Cohort Linked Birth/Infant Death Data Set (2007-2011: 20 685 463 births and 19 127 SUIDs). SUID was defined as deaths at <1 year of age with International Classification of Diseases, 10th Revision codes R95 (sudden infant death syndrome), R99 (ill-defined or unknown cause), or W75 (accidental suffocation or strangulation in bed).

RESULTS

SUID risk more than doubled (adjusted odds ratio [aOR] = 2.44; 95% confidence interval [CI] 2.31-2.57) with any maternal smoking during pregnancy and increased twofold between no smoking and smoking 1 cigarette daily throughout pregnancy. For 1 to 20 cigarettes per day, the probability of SUID increased linearly, with each additional cigarette smoked per day increasing the odds by 0.07 from 1 to 20 cigarettes; beyond 20 cigarettes, the relationship plateaued. Mothers who quit or reduced their smoking decreased their odds compared with those who continued smoking (reduced: aOR = 0.88, 95% CI 0.79-0.98; quit: aOR = 0.77, 95% CI 0.67-0.87). If we assume causality, 22% of SUIDs in the United States can be directly attributed to maternal smoking during pregnancy.

CONCLUSIONS

These data support the need for smoking cessation before pregnancy. If no women smoked in pregnancy, SUID rates in the United States could be reduced substantially.

Prenatal Risk Factors for Adverse Developmental Outcome in Preterm Infants-Systematic Review

Background: Preterm infants are still at an increased risk for suboptimal neurodevelopmental outcomes when compared with term born infants. The development of a child born preterm can be jeopardized by suboptimal conditions during pregnancy, in addition to the suboptimal growth environment postnatally compared to the normal in utero environment. This review summarizes the literature on the role of chorioamnionitis, placental insufficiency, and maternal smoking on the developmental outcomes of preterm infants. Methods: A systematic database search was performed to identify all original articles published on or before September 12, 2018 that evaluated the impact of clinical or histological chorioamnionitis, abnormal prenatal fetal and placental blood flow, and prenatal smoking exposure on the neuropsychological and cognitive outcomes of preterm infants. We identified a total of 54 studies. Thirty five original articles evaluated the effects of clinical or histological chorioamnionitis; 15 studies evaluated the effects of abnormal blood flow patterns; and four studies evaluated the effects of maternal smoking during pregnancy. Results: The studies on prenatal risk factors showed conflicting results about the impact on the neurodevelopment of preterm infants. The majority of the studies did not show that chorioamnionitis poses a direct risk to the development of preterm infants. The role of abnormal prenatal placental and fetal blood flow on the development of preterm infants remained inconclusive because the sample sizes were often small and methodological problems complicated the interpretation of the data. Maternal smoking during pregnancy was assessed only in one cohort which showed that maternal smoking is a risk for suboptimal cognitive and neuropsychological development in preterm infants. Conclusions: This review summarizes the data on several prenatal risk factors which play a role in the developmental outcomes of preterm infants. To optimize the developmental outcomes, we need to first optimize the fetal wellbeing before birth. More research that extends from the fetal life to long-term developmental outcomes is needed.

Preventing sudden infant death syndrome and other sleep-related infant deaths

Sudden infant death syndrome, a type of sleep-related sudden unexpected infant death (SUID) is the leading cause of postneonatal mortality in the United States and the third leading cause of infant death overall. Despite the evidence-based risk-reduction strategies and the highly publicized campaigns for a safe sleep environment, some infants continue to sleep in unsafe sleep conditions. Clinicians need to know the current best practices to reduce the incidence of sleep-related SUID and be knowledgeable to counsel caregivers who may resist adhering to these recommendations. This article describes the different types of SUID, associated risk factors, and highlights recommendations to help parents and caregivers ensure safe sleep environments for infants.

Parental smoking during pregnancy and head shape and size in school children

BACKGROUND

Maternal smoking during pregnancy has been recognised as a detrimental factor associated with adverse perinatal outcomes; however, to date there is a dearth of information on how it affects post-natal head growth and shape.

AIM

To assess the relationship between parental smoking exposure during pregnancy and head dimensions and shape at age 7-10 years in boys and girls.

METHODS

Body height and head length, breadth and circumference were measured. Birth weight and gestational age were obtained from the children's medical record books. Parental smoking habits during pregnancy and maternal educational attainment were obtained by a questionnaire. The relationship between exposure to parental smoking during pregnancy and head dimensions was evaluated using analysis of covariance implemented in the Generalized Linear Model, separately for each sex.

RESULTS

Maternal and parental smoking during pregnancy significantly altered head shape in boys by affecting head length, while neither head breadth nor circumference were affected. This phenomenon was not observed in girls.

CONCLUSION

Smoking-induced chronic hypoxic effects on the growing foetus, indicated that both active and passive smoking during pregnancy seems to have persistent negative effects on children, going beyond foetal development and pre-natal growth restrictions.

Cigarette smoke exposure effects on the brainstem expression of nicotinic acetylcholine receptors (nAChRs), and on cardiac, respiratory and sleep physiologies

Cigarette smoking during pregnancy is the largest modifiable risk factor for adverse outcomes in the infant. Investigations have focused on the psychoactive component of cigarettes, nicotine. One proposed mechanism leading to adverse effects is the interaction between nicotine and its nicotinic acetylcholine receptors (nAChRs). Much data has been generated over the past three decades on the effects of cigarette smoke exposure (CSE) on the expression of the nAChRs in the brainstem and physiological parameters related to cardiac, respiration and sleep, in the offspring of smoking mothers and animal models of nicotine exposure. This review summarises this data and discusses the main findings, highlighting that findings in animal models closely correlate with those from human studies, and that the major brainstem sites where the expression level for the nAChRs are consistently affected include those that play vital roles in cardiorespiration (hypoglossal nucleus, dorsal motor nucleus of the vagus, nucleus of the solitary tract), chemosensation (nucleus of the solitary tract, arcuate nucleus) and arousal (rostral mesopontine sites such as the locus coeruleus and nucleus pontis oralis). These findings provide evidence for the adverse effects of CSE during and after pregnancy to the infant and the need to continue with the health campaign advising against CSE.

The Pēpi-Pod study: Overnight video, oximetry and thermal environment while using an in-bed sleep device for sudden unexpected death in infancy prevention

AIM

The aim of this study was to identify the potential risks and benefits of sleeping infants in a Pēpi-Pod distributed to families with high risk of sudden unexpected death in infancy compared to a bassinet.

METHODS

Forty-five mostly indigenous Māori mothers who were referred by local health providers to receive a Pēpi-Pod were surveyed at recruitment, 1 and 3 months. A sleep study at 1 month included infrared video, oximetry and temperature measures.

RESULTS

When compared with 89 historical bassinet controls, an intention-to-treat analysis of questionnaires showed no increase in direct bed sharing but demonstrated significantly less sharing of the maternal bedroom at both interviews, with the majority of those not sleeping in the maternal bedroom, actually sleeping in the living room. The 1 month 'as-used' analysis showed poorer maternal sleep quality. The 'as-used' analysis of video data (24 Pēpi-Pod and 113 bassinet infants) also showed no increase in direct bed sharing, head covering or prone/side sleep position. Differences in oxygen saturation were not significant, but heart rate was higher in the Pēpi-Pod infants by 8.37 bpm (95% confidence interval 4.40, 12.14). Time in the thermal comfort zone was not different between groups despite Pēpi-Pod infants being situated in significantly warmer rooms.

CONCLUSIONS

Overall, we found that most differences in infant risk behaviours in a Pēpi-Pod compared to a bassinet were small, with confidence intervals excluding meaningful differences. We noted poorer maternal sleep quality at 1 month. Higher infant heart rates in the Pēpi-Pod group may be related to higher room temperatures. The Pēpi-Pod appears physiologically safe but is associated with lower reported maternal sleep quality.

Barriers to and facilitators of smoking cessation in pregnancy and following childbirth: literature review and qualitative study

BACKGROUND

Although many women stop smoking in pregnancy, others continue, causing harm to maternal and child health. Smoking behaviour is influenced by many factors, including the role of women's significant others (SOs) and support from health-care professionals (HPs).

OBJECTIVES

To enhance understanding of the barriers to, and facilitators of, smoking cessation and the feasibility and acceptability of interventions to reach and support pregnant women to stop smoking.

DESIGN

Four parts: (1) a description of interventions in the UK for smoking cessation in pregnancy; (2) three systematic reviews (syntheses) of qualitative research of women's, SOs' and HPs' views of smoking in pregnancy using meta-ethnography (interpretative approach for combining findings); (3) semistructured interviews with pregnant women, SOs and HPs, guided by the social-ecological framework (conceptualises behaviour as an outcome of individuals' interactions with environment); and (4) identification of new/improved interventions for future testing.

SETTING

Studies in reviews conducted in high-income countries. Qualitative research was conducted from October 2013 to December 2014 in two mixed urban/rural study sites: area A (Scotland) and area B (England).

PARTICIPANTS

Thirty-eight studies (1100 pregnant women) in 42 papers, nine studies (150 partners) in 14 papers and eight studies described in nine papers (190 HPs) included in reviews. Forty-one interviews with pregnant women, 32 interviews with pregnant women's SOs and 28 individual/group interviews with 48 HPs were conducted.

MAIN OUTCOME MEASURES

The perceived barriers to, and facilitators of, smoking cessation in pregnancy and the identification of potential new/modified interventions.

RESULTS

Syntheses identified smoking-related perceptions and experiences for pregnant women and SOs that were fluid and context dependent with the capacity to help or hinder smoking cessation. Themes were analysed in accordance with the social-ecological framework levels. From the analysis of the interviews, the themes that were central to cessation in pregnancy at an individual level, and that reflected the findings from the reviews, were perception of risk to baby, self-efficacy, influence of close relationships and smoking as a way of coping with stress. Overall, pregnant smokers were faced with more barriers than facilitators. At an interpersonal level, partners' emotional and practical support, willingness to change smoking behaviour and role of smoking within relationships were important. Across the review and interviews of HPs, education to enhance knowledge and confidence in delivering information about smoking in pregnancy and the centrality of the client relationship, protection of which could be a factor in downplaying risks, were important. HPs acknowledged that they could best assist by providing support and understanding, and access to effective interventions, including an opt-out referral pathway to Stop Smoking Services, routine carbon monoxide screening, behavioural support and access to pharmacotherapy. Additional themes at community, organisational and societal levels were also identified.

LIMITATIONS

Limitations include a design grounded in qualitative studies, difficulties recruiting SOs, and local service configurations and recruitment processes that potentially skewed the sample.

CONCLUSIONS

Perceptions and experiences of barriers to and facilitators of smoking cessation in pregnancy are fluid and context dependent. Effective interventions for smoking cessation in pregnancy should take account of the interplay between the individual, interpersonal and environmental aspects of women's lives.

FUTURE WORK

Research focus: removing barriers to support, improving HPs' capacity to offer accurate advice, and exploration of weight concerns and relapse prevention. Interventions focus: financial incentives, self-help and social network interventions.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42013004170.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Effect of maternal smoking on stress physiology in healthy neonates

OBJECTIVE

To assess the impact of maternal smoking during pregnancy (MSDP) on the neonatal hypothalamic-pituitary-adrenal axis.

STUDY DESIGN

In a prospective observational study, salivary cortisol and cortisone levels were measured at the fourth day of life during resting conditions and in response to a pain-induced stress event in healthy neonates whose mothers smoked cigarettes during each stage of pregnancy and compared with controls.

RESULTS

Neonates in the control group (n=70) exhibited a physiologic stress response with a significant increase in cortisol (1.3 to 2.1 ng ml^-1; P<0.05) and cortisone (11.8 to 17.8 ng ml^-1; P<0.05) from baseline levels, whereas in neonates from mothers who smoked (n=33), cortisol (0.9 to 0.8 ng ml^-1; P=0.77) and cortisone (11.5 to 13.0; P=0.19) stress response was not significantly different from baseline levels. A two-way analysis of variance confirmed these findings in both groups.

CONCLUSIONS

Healthy neonates whose mothers smoked during pregnancy show a blunted stress response on the fourth day of life. Thus, MSDP leads to a dysregulation of the HPA axis with continued effects in neonatal life. This might explain long-term consequences of MSDP such as overweight, diabetes mellitus and modification of blood pressure control mechanisms in adult life.

Vitamin E as an Antioxidant in Female Reproductive Health

Vitamin E was first discovered in 1922 as a substance necessary for reproduction. Following this discovery, vitamin E was extensively studied, and it has become widely known as a powerful lipid-soluble antioxidant. There has been increasing interest in the role of vitamin E as an antioxidant, as it has been discovered to lower body cholesterol levels and act as an anticancer agent. Numerous studies have reported that vitamin E exhibits anti-proliferative, anti-survival, pro-apoptotic, and anti-angiogenic effects in cancer, as well as anti-inflammatory activities. There are various reports on the benefits of vitamin E on health in general. However, despite it being initially discovered as a vitamin necessary for reproduction, to date, studies relating to its effects in this area are lacking. Hence, this paper was written with the intention of providing a review of the known roles of vitamin E as an antioxidant in female reproductive health.

Detoxification genes polymorphisms in SIDS exposed to tobacco smoke

The best hypothesis to explain Sudden Infant Death Syndrome (SIDS) pathogenesis is offered by the "triple risk model", which suggests that an interaction of different variables related to exogenous stressors and infant vulnerability may lead to the syndrome. Environmental factors are triggers that act during a particular sensible period, modulated by intrinsic genetic characteristics. Although literature data show that one of the major SIDS risk factors is smoking exposure, a specific involvement of molecular components has never been highlighted. Starting from these observations and considering the role of GSTT1 and GSTM1 genes functional polymorphisms in the detoxification process, we analyzed GSTM1 and GSTT1 null genotype frequencies in 47 SIDS exposed to tobacco smoke and 75 healthy individuals. A significant association (p < .0001) between the GSTM1 null genotype and SIDS exposed to smoke was found. On the contrary, no association between GSTT1 polymorphism and SIDS was determined. Results indicated the contribution of the GSTM1 -/- genotype resulting in null detoxification activity in SIDS cases, and led to a better comprehension of the triple risk model, highlighting smoking exposure as a real SIDS risk factor on a biochemical basis.

Income Inequality and US Children's Secondhand Smoke Exposure: Distinct Associations by Race-Ethnicity

Introduction

Prior studies have found considerable racial and ethnic disparities in secondhand smoke (SHS) exposure. Although a number of individual-level determinants of this disparity have been identified, contextual determinants of racial and ethnic disparities in SHS exposure remain unexamined. The objective of this study was to examine disparities in serum cotinine in relation to area-level income inequality among 14 649 children from the National Health and Nutrition Examination Survey.

Methods

We fit log-normal regression models to examine disparities in serum cotinine in relation to Metropolitan Statistical Areas level income inequality among 14 649 nonsmoking children aged 3-15 from the National Health and Nutrition Examination Survey (1999-2012).

Result

Non-Hispanic black children had significantly lower serum cotinine than non-Hispanic white children (-0.26; 95% CI: -0.38, -0.15) in low income inequality areas, but this difference was attenuated in areas with high income inequality (0.01; 95% CI: -0.16, 0.18). Serum cotinine declined for non-Hispanic white and Mexican American children with increasing income inequality. Serum cotinine did not change as a function of the level of income inequality among non-Hispanic black children.

Conclusions

We have found evidence of differential associations between SHS exposure and income inequality by race and ethnicity. Further examination of environments which engender SHS exposure among children across various racial/ethnic subgroups can foster a better understanding of how area-level income inequality relates to health outcomes such as levels of SHS exposure and how those associations differ by race/ethnicity.

Implications

In the United States, the association between children's risk of SHS exposure and income inequality is modified by race/ethnicity in a manner that is inconsistent with theories of income inequality. In overall analysis this association appears to be as predicted by theory. However, race-specific analyses reveal that higher levels of income inequality are associated with lower levels of SHS exposure among white children, while levels of SHS exposure among non-Hispanic black children are largely invariant to area-level income inequality. Future examination of the link between income inequality and smoking-related health outcomes should consider differential associations across racial and ethnic subpopulations.