In utero and postnatal exposure to environmental tobacco smoke, blood pressure, and hypertension in children: the Seven Northeastern Cities study

The Impact of Prenatal Environmental Tobacco Smoking (ETS) and Exposure on Chinese Children: A Systematic Review

Background: There is considerable evidence to support the association between exposure to environmental tobacco smoke (ETS) and children's burden of disease. However, the literature on the health outcomes of prenatal ETS exposure among Chinese children has not yet been comprehensively reviewed. Objective: This systematic review examines the currently available evidence and identifies gaps for further research on the health consequences of prenatal ETS exposure on Chinese children. Methods: Following the JBI systematic-scoping review methodological framework, we conducted a computer-aided search of three electronic databases-PubMed, EBSCOhost, and ProQuest to include studies from January 2011 to May 2023 that addressed the health outcomes of Chinese children whose mothers were exposed to ETS at any stage of pregnancy. Furthermore, a methodological quality assessment of the selected articles was conducted using JBI critical appraisal checklists. Results: A total of 30 articles were reviewed, including eleven high-quality studies and nineteen moderate-quality studies. Five main themes, including hypertension, fetal and children's development, behavioural disorders, respiratory outcomes, and "other health outcomes", were encompassed. The majority of the studies showed a positive link between prenatal ETS exposure and an increased risk of preterm birth, and moderate risk of fetal growth restriction. A few studies explored other potential adverse outcomes of ETS, including hypertension, respiratory morbidity, lung function, and asthma in children. Conclusions: The currently available evidence on prenatal ETS exposure in Chinese children has unveiled a wide range of health outcomes, including preterm birth, fetal development, behavioural disorders, and much more. However, Chinese studies in this area are still lacking and a gap still exists in relation to the strength of association between prenatal ETS exposure and some health risks. Efficient anti-smoking policies and smoking cessation programs should be developed to promote maternal and child health. Further research is also needed to provide better evidence in this field.

Maternal smoking in pregnancy and blood pressure during childhood and adolescence: a meta-analysis

Arterial hypertension during childhood or adolescence is rising, and smoking during pregnancy may constitute a modifiable risk factor. This study aims to evaluate the effect of maternal smoking during pregnancy on diastolic (DBP) and systolic blood pressure (SBP) in childhood and adolescence. A bibliographic search was conducted in PubMed, Embase, and CENTRAL databases in March 2022. Meta-analysis was performed with the difference in mean-adjusted SBP/DBP of children and adolescents aged 3-17 years, according to maternal smoking/non-smoking in pregnancy. A random effects model was applied; a leave-one-out analysis and meta-analysis by subgroups were performed. A modified Newcastle-Ottawa scale was used to assess the quality of the studies. Evidence levels were rated using the GRADE system. Fifteen studies were included in the meta-analysis; all of them evaluated the mean-adjusted SBP difference in children or adolescents (N = 73,448), and 6 also that of DBP (N = 31,459). Results showed that maternal smoking during pregnancy significantly increased SBP (β = 0.31 mmHg 95% CI 0.14-0.49). A greater increase in mean-adjusted SBP was observed in those studies that completed the recruitment before 1990, were conducted in non-European countries, used standard mercury or manual sphygmomanometry, adjusted for birth weight, and were in the lowest quality subgroup. No significant association was found for DBP. The GRADE level of evidence was low for SBP and very low for DBP.

CONCLUSION

Smoking in pregnancy might increase SBP in childhood and adolescence. Due to the low level of evidence, solid inferences cannot be drawn about the clinical relevance of these findings.

WHAT IS KNOWN

• AHT is the leading cause of premature death among adults worldwide. • Deleterious effects derived from SHS exposure on children's health have been documented since early 1970. To date, there are contradictory results about the effects of prenatal SHS exposure on children's BP.

WHAT IS NEW

• Smoking in pregnancy may increase SBP during childhood and adolescence. • Maternal smoking during pregnancy could have greater influence on their offspring's SBP than on DBP.

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.

Aortic Valve Calcification Score in Patients with Arterial Hypertension Environmentally Exposed to Tobacco Smoke

The objective of our study was to determine the relationship between exposure to environmental tobacco smoke (ETS) and the value of the aortic valve calcification score (AVCS) in people suffering from arterial hypertension (AH). 107 non-smokers with AH (mean age 67.16 ± 8.48 years) were qualified for the study. The degree of exposure to ETS was assessed using the Second-hand Smoke Exposure Scale (SHSES) questionnaire. Study group was divided depending on ETS exposure: A—no exposure, B—low, C—medium and D—high. AVCS was measured based on the aortic valve plane multiplanar reconstruction from the non-contrast phase of the cardiac computed tomography. The Agatston algorithm was used, in which calcifications were considered changes with a density exceeding 130 HU. The mean AVCS value in the study group of patients was 213.59 ± 304.86. The AVCS was significantly lower in subgroup A than in subgroups C and D. In subgroup A, the lack of aortic valve calcification (AVCS = 0) was observed significantly more frequently than in subgroups C and D. There was a positive correlation between the number of SHSES points and the AVCS value (r = 0.37, p < 0.05). Based on the ROC curve, the SHSES value was determined as the optimal cut-off point for the prediction of AVCS = 0, amounting to 3 points. The accuracy of SHSES < 3 as the predictor of AVCS = 0 was set at 62.18%. Hypertensive patients have an unfavourable relationship between the amount of exposure to ETS, determined on the SHSES scale, and the AVCS value.

Birthweight DNA methylation signatures in infant saliva

Background

Low birthweight has been repeatedly associated with long-term adverse health outcomes and many non-communicable diseases. Our aim was to look-up cord blood birthweight-associated CpG sites identified by the PACE Consortium in infant saliva, and to explore saliva-specific DNA methylation signatures of birthweight.

Methods

DNA methylation was assessed using Infinium HumanMethylation450K array in 135 saliva samples collected from children of the NINFEA birth cohort at an average age of 10.8 (range 7–17) months. The association analyses between birthweight and DNA methylation variations were carried out using robust linear regression models both in the exploratory EWAS analyses and in the look-up of the PACE findings in infant saliva.

Results

None of the cord blood birthweight-associated CpGs identified by the PACE Consortium was associated with birthweight when analysed in infant saliva. In saliva EWAS analyses, considering a false discovery rate p-values < 0.05, birthweight as continuous variable was associated with DNA methylation in 44 CpG sites; being born small for gestational age (SGA, lower 10^th percentile of birthweight for gestational age according to WHO reference charts) was associated with DNA methylation in 44 CpGs, with only one overlapping CpG between the two analyses. Despite no overlap with PACE results at the CpG level, two of the top saliva birthweight CpGs mapped at genes associated with birthweight with the same direction of the effect also in the PACE Consortium (MACROD1 and RPTOR).

Conclusion

Our study provides an indication of the birthweight and SGA epigenetic salivary signatures in children around 10 months of age. DNA methylation signatures in cord blood may not be comparable with saliva DNA methylation signatures at about 10 months of age, suggesting that the birthweight epigenetic marks are likely time and tissue specific.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13148-021-01053-1.

Factors Associated with Primary Hypertension in Pediatric Patients: An Up-to-Date

BACKGROUND

Arterial hypertension in children is considered a common alteration nowadays, mainly because obesity is a growing worldwide problem closely related to increased blood pressure. Childhood hypertension can be classified as primary or secondary, depending on the etiology. Primary or essential hypertension still has its pathophysiology not fully elucidated, and there is no consensus in the literature on most underlying mechanisms. In this review, genetic and environmental factors, including sodium and potassium intake, socioeconomic status, ethnicity, family structure, obesity, sedentary lifestyle, prematurity and low birth weight, prenatal and postnatal exposures are highlighted.

OBJECTIVE

The present study aimed to perform an update on primary hypertension in childhood, providing clinicians and researchers an overview of the current state of the literature regarding the influence of genetic and environmental factors.

METHODS

This integrative review searched for articles on genetic and environmental factors related to primary hypertension in pediatric patients. The databases evaluated were PubMed and Scopus.

RESULTS

The studies have provided insights regarding many genetic and environmental factors, in addition to their association with the pathophysiology of primary hypertension in childhood. Findings corroborated the idea that primary hypertension is a multifactorial disease. Further studies in the pediatric population are needed to elucidate the underlying mechanisms.

CONCLUSION

The study of primary hypertension in pediatrics has utmost importance for the adoption of preventive measures and the development of more efficient treatments, therefore reducing childhood morbidity and the incidence of cardiovascular diseases and other health consequences later in life.