Perinatal and early childhood factors for overweight and obesity in young Canadian children

Impact of parental lifestyle patterns in the preconception and pregnancy periods on childhood obesity

Introduction

High prevalence of overweight and obesity already observed in preschool children suggests the involvement of early-life risk factors. Preconception period and pregnancy are crucial windows for the implementation of child obesity prevention interventions with parental lifestyle factors as relevant targets. So far, most studies have evaluated their role separately, with only a few having investigated their potential synergistic effect on childhood obesity. Our objective was to investigate parental lifestyle patterns in the preconception and pregnancy periods and their association with the risk of child overweight after 5 years.

Materials and methods

We harmonized and interpreted results from four European mother-offspring cohorts participating in the EndObesity Consortium [EDEN, France; Elfe, France; Lifeways, Ireland; and Generation R, Netherlands] with data available for 1,900, 18,000, 1,100, and 9,500 families, respectively. Lifestyle factors were collected using questionnaires and included parental smoking, body mass index (BMI), gestational weight gain, diet, physical activity, and sedentary behavior. We applied principal component analyses to identify parental lifestyle patterns in preconception and pregnancy. Their association with risk of overweight (including obesity; OW-OB) and BMI z-scores between 5 and 12 years were assessed using cohort-specific multivariable logistic and linear and regression models (adjusted for potential confounders including parental age, education level, employment status, geographic origin, parity, and household income).

Results

Among the various lifestyle patterns derived in all cohorts, the two explaining the most variance were characterized by (1) "high parental smoking, low maternal diet quality (and high maternal sedentary behavior in some cohorts)" and, (2) "high parental BMI and low gestational weight gain." Patterns characterized by high parental BMI, smoking, low diet quality or high sedentary lifestyle before or during pregnancy were associated with higher risk of OW-OB in children, and BMI z-score at any age, with consistent strengths of associations in the main cohorts, except for lifeways.

Conclusion

This project provides insight into how combined parental lifestyle factors in the preconception and pregnancy periods are associated with the future risk of child obesity. These findings are valuable to inform family-based and multi-behavioural child obesity prevention strategies in early life.

Meta-Analysis on Associations of Timing of Maternal Smoking Cessation Before and During Pregnancy With Childhood Overweight and Obesity

INTRODUCTION

There is a lack of comprehensive review on associations of maternal smoking cessation (versus nonsmokers) with childhood overweight and obesity.

AIMS AND METHODS

We conducted a systematic review and meta-analysis of existing evidence in this field. Within PubMed, EMBASE, and CENTRAL databases, we identified and screened 1147 abstracts. We reviewed full-texts and extracted related information from 10 eligible articles. We pooled odds ratios for overweight/obesity and mean differences in BMI z-scores by maternal smoking status around pregnancy.

RESULTS

Among 10 eligible studies, 71 393 children were included from ages 2 to 18 years. Compared to children of nonsmokers, the pooled unadjusted odds ratio (OR) for overweight was 1.36 (95% Confidence Interval CI: 1.14, 1.62) in children of quitters and 1.44 (1.27, 1.64) in children of continued smokers. The pooled unadjusted OR for obesity was 1.65 (1.17, 2.32) in children of quitters and 1.94 (1.38, 2.73) in children of continued smokers. The pooled unadjusted mean difference in BMI z-score was 0.51 (0.41, 0.61) in children of quitters and 0.64 (0.58, 0.70) in children of continued smokers. The pooled unadjusted OR for overweight in children of mothers quitting before pregnancy was 1.46 (1.15, 1.85), during the first trimester was 1.52 (1.27, 1.82), and during pregnancy (mixed timing, mostly first trimester) was 0.97 (0.79, 1.20).

CONCLUSION

The risk of offspring overweight and obesity was moderately higher for quitters during pregnancy compared to nonsmokers, although it might not be as high as continued smokers.

IMPLICATIONS

Maternal smoking during pregnancy is an established risk factor of childhood overweight and obesity. Based on our systematic review, intervention to help mothers quit smoking has the potential to reduce the risk of childhood overweight and obesity in offspring related to prenatal tobacco exposure. Quitting before pregnancy is ideal, but quitting in early pregnancy is still helpful for reducing risk.

Associations Between Rurality, pre-pregnancy Health Status, and Macrosomia in American Indian/Alaska Native Populations

OBJECTIVES

To examine the relationships between pre-pregnancy diabetes mellitus (DM), gestational diabetes mellitus (GDM), pre-pregnancy body mass index (BMI) and county-level social determinants of health, with infant macrosomia within a sample of American Indian/Alaska Native (AI/AN) women receiving Indian Health Service (IHS) care.

METHODS

The sample included women-infant dyads representing 1,136 singleton births from fiscal year 2011 (10/1/2019-9/30/2011). Data stemmed from the IHS Improving Health Care Delivery Data Project. Multivariate generalized linear mixed models were fitted to assess the association of macrosomia with pre-pregnancy health status and social determinants of health.

RESULTS

Nearly half of the women in the sample were under age 25 years (48.6%), and most had Medicaid health insurance coverage (76.7%). Of those with a pre-pregnancy BMI measure, 66.2% were overweight or obese. Although few women had pre-pregnancy DM (4.0%), GDM was present in 12.8% of women. Most women had a normal term delivery (85.4%). Overweight, obesity, pre-pregnancy DM, and county-level rurality were all significantly associated with higher odds of infant macrosomia.

Facilitators, Barriers, and Structural Determinants of Physical Activity in Nulliparous Pregnant Women: A Qualitative Study

Aims & Backgrounds. Reduced physical activity in pregnant women is highly stemmed from their misconceptions and attitudes during pregnancy. This study is aimed at recognizing the facilitators, barriers, and structural factors that influence activity among pregnant women. Participants & Methods. This qualitative study was conducted from January to June 2020 in nulliparous pregnant women. Forty participants selected randomly from the Pounak Health Center of Tehran City, Iran, answered open-ended questions about the obstacles that deprived them of physical activity during pregnancy. Data were analyzed by MAXQDA 12 software. Findings. 620 primary codes, 42 secondary codes, 11 subthemes, and 6 themes were extracted. These themes were divided into the PEN-3 categories: facilitators, barriers, and structural factors. The nurture factors as facilitators had communication and support from others as subthemes. Barriers consisted of sociocultural (participate in pregnancy class with a companion, social beliefs, and culture of poverty), socioeconomic (financial problems), and individual factors (physical, psychoemotional, and spiritual dimensions), and structural factors consisted of environmental (equipment) and organizational (possibilities in health centers) factors. Conclusion. Lack of awareness and misinformation, accessibility obstacles, and economic problems are the worst physical activity barriers during pregnancy. Being among other pregnant women and the physicians’ recommendations are the best facilitators of physical activity during pregnancy.

Birth weight for gestational age and later cardiovascular health: a comparison between longitudinal Finnish and indigenous Australian cohorts

INTRODUCTION

Small or large birth weight for gestational age has been linked with later cardiovascular disease risk. However, cardiovascular risk markers from childhood to adulthood according to birth weight in diverse longitudinal settings globally have not been extensively studied.

OBJECTIVES

To examine the relationship between birth weight and cardiovascular risk profile from childhood until young adulthood in two geographically and socioeconomically distinct cohorts.

METHODS

Data were derived from two longitudinal birth cohort studies; one from southern Finland (Special Turku Coronary Risk Factor Intervention Project, STRIP) and one from northern Australia comprising Indigenous Australians (Aboriginal Birth Cohort, ABC). The sample included 747 Finnish participants and 541 Indigenous Australians with data on birth weight, gestational age and cardiovascular risk factors (body mass index [BMI]), waist-to-height ratio [WHtR], lipid profile, blood pressure) collected at ages 11, 18 and 25 or 26 years. Carotid intima-media thickness (cIMT) was assessed at age 18 or 19 years. Participants were categorised according to birth weight for gestational age (small [SGA], appropriate [AGA] or large [LGA]). Associations between birth weight category and cardiovascular risk markers were studied using a repeated measures ANOVA.

RESULTS

Higher birth weight category was associated with higher BMI later in life in both cohorts (p=.003 for STRIP and p<.0001 for ABC). In the ABC, higher birth weight category was also associated with higher WHtR (p=.004). In the ABC, SGA participants had lower systolic and diastolic blood pressure than AGA participants (p=.028 for systolic, p=.027 for diastolic) and lower systolic blood pressure than LGA participants (p=.046) at age 25. In the STRIP cohort, SGA participants had lower cIMT than LGA participants (p=.024).

CONCLUSIONS

Birth weight can predict future cardiovascular risk profile in diverse populations. Thus, it needs to be included in targeted public health interventions for tackling the obesity pandemic and improving cardiovascular health worldwide.Key messagesThe strongest association between birth weight and later cardiovascular risk profile was manifested as differences in body mass index in two culturally and geographically distinct cohorts.Foetal growth is a determinant for later cardiovascular health in diverse populations, indicating a need to focus on maternal and foetal health to improve cardiovascular health worldwide.

Assessing the association between breastfeeding, type of childbirth and family structure with childhood obesity: results from an observational study among 10-12 years old children

This study examined the association between breastfeeding, type of childbirth, and family structure with childhood obesity. During 2014-2016, 1728 Greek students attending primary schools and their parents were enrolled. Children's weight status was measured and classified according to the International Obesity Task Force criteria. A self-administered questionnaire assessing the type of childbirth, the family structure, and several perinatal and demographic characteristics was used. Factors associated with higher breastfeeding rates were the type of childbirth, high maternal educational level, and nuclear family structure. No association was found between childhood obesity and type of childbirth (p = 0.64) and family structure (p = 0.26). Although the short-term beneficial effects of breastfeeding on childhood obesity are undeniable and it is of great importance to all health professionals to promote breastfeeding, no significant long-term effects on obesity in adolescence were observed. More studies are needed in order to elucidate the role of breastfeeding in obesity status in adolescence.

Prediction model study of overweight and obesity in preschool children with allergic diseases from an ecological perspective

Background

Allergic diseases have a high incidence in childhood and a high chance to be carried over into adulthood unless appropriately treated during childhood, it is important that healthcare providers actively manage these diseases. This study was to identify multidimensional factors that affect weight gain in preschool children with allergic diseases.

Methods

The overweight and obesity prediction model for children with allergic diseases was analyzed using multiple logistic regression analysis and a decision tree model and the present study was a secondary data analysis study that used data from the Panel Study on Korean Children conducted by the Korea Institute of Child Care and Education.

Results

The significance of this study is identify multidimensional factors that affect weight gain in preschool children with allergic diseases, which found that children (gender, sitting time during weekdays, sleeping hours during weekends,), parent (education level, mother’s job, quality of the home environment), local community (convenience of local community facilities, satisfaction level with local community facilities, quality of childcare in the local community) characteristics affected overweight and obesity at multidimensional levels as risk factors.

Conclusions

The significance of this study is identify multidimensional factors that affect weight gain in preschool children with allergic diseases using the data of the Panel Study on Korean Children, which found that children, parent, local community characteristics affected overweight and obesity at multidimensional levels as risk factors.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-021-02515-4.

High birth weight and risk of multiple sclerosis: A multicentre study in Argentina

BACKGROUND

Multiple sclerosis (MS) is now recognized as a multifactorial disease in which genetic and environmental factors intervene. Considerable efforts have been made to identify external risk factors present in childhood, adolescence and youth, though only a few perinatal risk factors have been positively associated with MS. Previously, we found an association between high birth weight and MS in male patients in a small study in Argentina. The present research was designed to further assess the association between high birth weight and MS in a larger sample of patients, using an extensive and validated general population database as control.

METHODS

We present an analytical observational, multicentre, population-based, and case-control study. A total of 637 patients (cases) with confirmed MS diagnosis attending five MS specialized centres in Argentina were included. Birth weight (BW) data was recalled by the patient's mother, which is a validated approach. A two-way comparison was performed. First, we used the standard categories of high, adequate and low BW in grams. Then, we applied the weight percentile distribution to provide reproducible results for further research. For a proper assessment and comparison of variables, we adopted the guidelines of the American Academy of Pediatrics for neonate classification according to gestational weeks and to BW in grams. The neonate's BW distribution of the general population was used as control. For the purposes of the study, we adapted Urquía's et al. curves, which are based on an extensive database of all the live births registered in the country from 2003 to 2007. To measure the magnitude of the proportional differences between low, adequate and high BW, the odds ratio (OR) and their 95% confidence interval (CI) were estimated. The mean BW and percentile values for each sex were compared using a z-Normal test. The respective MS patients and general population BW distribution curves by sex were compared between each other.

RESULTS

Cases and controls were comparable in their demographic, geographic and environmental characteristics. Males showed higher BW than females both in the MS patients and the general population groups. When we applied the sex stratified analysis separately, we found that males in the MS group showed an almost seven times higher risk of high birth weight than males from the general population (OR 6.58 [95% CI 4.81-8.99]). Female patients showed an almost five times higher risk of high BW than their respective controls (OR 4.5 [95% CI 3.06-6.58]). The comparison based on the BW percentile distribution confirmed that MS patients showed higher BW than the general population. This result reached statistical significance from the 75^th percentile onwards for both sexes.

CONCLUSION

In summary, our findings suggested that high BW could be one of the earliest risk factors for MS in life. If this results were reproduced in other centres, high birth weight would emerge as a novel and very early risk factor, potentially modifiable in utero or immediately postpartum, representing a unique opportunity to prevent the disease in future generations.

Risk Factors in Early Life for Preschool Children in Korea that are Associated with Being Overweight or Obese

OBJECTIVES

The present study addressed the risk factors in early life for Korean preschool children that are associated with being overweight or obese.

METHODS

A descriptive cross-sectional design was used to conduct this study, which included 507 mothers with preschool children aged 3-5 years, who attended daycare centers. Data were acquired via a self-administered questionnaire completed by the mothers. Of the 650 questionnaires that were distributed, 507 (78%) were completed and sent back. Multivariate logistic regression analyses were used to identify risk factors in early life, which may contribute to being overweight or obese in preschool children.

RESULTS

Fifty-eight (11.4%) preschool children were overweight and 41 (8.1%) were obese. Multivariate logistic regression analysis with adjustment for covariates, revealed a significant association with the introduction of solid foods before 4 months of age [adjusted odds ratio (aOR) = 9.49, p = 0.029] and a nonresponsive feeding style (aOR = 2.80, p = 0.043) with being overweight or obese in preschool children.

CONCLUSION

The findings of this study highlighted the need for parenting education programs on feeding practices to increase their understanding of hunger and satiety cues in infants, and appropriate timing for the introduction of solid foods.

Association between neonatal serum bilirubin and childhood obesity in preterm infants

BACKGROUND

Serum bilirubin levels are inversely associated with obesity in adults. We are interested in whether neonatal jaundice is associated with childhood obesity in preterm infants.

METHODS

Data were obtained from the US Collaborative Perinatal Project. Neonatal bilirubin levels were used as exposure factors for obesity at age 7 years. Logistic regression models were used to control for potential confounders and calculate odds ratios (ORs). A generalized estimating equation (GEE) model was used to correct for intracluster correlation coefficient. SAS was used for all statistical analyses.

RESULTS

In the study subjects, 865 of 5019 preterm infants were obese at age 7 years. While neonatal total serum bilirubin (TSB) rose 1 mg/dl, body mass index (BMI) increased 0.03 kg/m² (95% confidence interval (CI) 0.02, 0.04). Compared with infants with TSB <3 mg/dl, the ORs (95% CIs) for obesity in infants with 3 mg/dl≤ TSB <6 mg/dl, 6 mg/dl≤ TSB <9 mg/dl, 9 mg/dl≤ TSB <12 mg/dl and TSB ≥12 mg/dl were, respectively, 1.18 (0.87, 1.59), 1.25 (0.93, 1.67), 1.52 (1.11, 2.09), and 1.67 (1.22, 2.07). By using subtypes of bilirubin as exposure factors and the GEE model to correct for intracluster correlation coefficient, similar trends of associations were observed.

CONCLUSION

Neonatal bilirubin levels have positive trends of associations with childhood obesity in preterm infants.

Maternal smoking during pregnancy and offspring body mass index and overweight: a systematic review and meta-analysis

Abstract: The present study aimed to conduct a systematic review and meta-analysis to evaluate the evidence on the association of maternal smoking during pregnancy with offspring body composition in childhood, adolescence and adulthood. MEDLINE, Web of Science and LILACS databases were searched. Reference lists were also screened. We included original studies, conducted in humans, that assessed the association of maternal smoking during pregnancy with offspring body mass index (BMI) and overweight in childhood, adolescence and adulthood, published through May 1st, 2018. A meta-analysis was used to estimate pooled effect sizes. The systematic review included 64 studies, of which 37 evaluated the association of maternal smoking during pregnancy with overweight, 13 with BMI, and 14 evaluated both outcomes. Of these 64 studies, 95 measures of effect were extracted and included in the meta-analysis. We verified that the quality of evidence across studies regarding maternal smoking in pregnancy and overweight and BMI of offspring to be moderate and low, respectively. Most studies (44 studies) were classified as moderate risk bias. Heterogeneity among studies included was high and, in the random-effects pooled analysis, maternal smoking during pregnancy increased the odds of offspring overweight (OR: 1.43, 95%CI: 1.35; 1.52) and mean difference of BMI (β: 0.31, 95%CI: 0.23; 0.39). In conclusion, offspring of mothers who smoked during pregnancy have higher odds of overweight and mean difference of BMI, and these associations persisted into adulthood.

The impact of perinatal history in the occurrence of childhood obesity: a litera-ture review

BACKGROUND

It is widely accepted, that the increased prevalence of childhood overweight and obesity poses an important public health problem since it increases the risk for early onset of non-communicable diseases with potentially increased health complications during adulthood. Childhood obesity prevention is therefore of primary importance; hence it is mandatory to understand its main causes and identify the mechanisms associated with weight gain. Although its etiology can be partly attributed to genetic and behavioral factors, evidence from existing literature indicates that the perinatal environment may also increase the risk of childhood obesity; the latter, however, has not been thoroughly investigated and discussed.

METHODS

A literature search was conducted in scientific databases (PubMed, Embase, Web of Science, and Scopus) in order to reveal recent epidemiologic studies, with emphasis on works from the last decade. Studies whose primary or secondary object was the association between type of delivery, breastfeeding and/or gestational diabetes mellitus with overweight and obesity in childhood and preadolescence were taken into account. Studies that did not meet the aim of the current review were excluded.

RESULTS

The retrieved information revealed that there is a noteworthy association between perinatal factors and childhood and preadolescence overweight/obesity occurrence, though the exact pathways still need to be elucidated.

CONCLUSIONS

Public health professionals should take into account perinatal determinants when estimating a child's risk of overweight and obesity development. HIPPOKRATIA 2018, 22(4): 155-161.

Leveraging the Canadian Health Measures Survey for environmental health research

Since 2007, the nationally representative, cross-sectional Canadian Health Measures Survey (CHMS) has collected detailed health and exposure data from more than 25,000 Canadians, including a wide range of chemical biomarkers analyzed in blood, urine, and environmental media. This article highlights the extent to which the CHMS dataset has been used in the peer-reviewed environmental health literature and opportunities for further expanding usage of the dataset. A literature search (2007-2018) was performed to identify peer-reviewed studies that have made substantive use of the CHMS dataset. Studies were analyzed according to the study type, data usage, populations studied, environmental health themes, citation/publication data, and institutional collaborations. A total of 51 environmental-health related CHMS studies were identified, including studies related to indoor and outdoor air quality, the built environment, and chemical and environmental tobacco smoke exposures. Health indicator data are being increasingly exploited, as is the ability to combine cycle datasets over time. Although these studies covered a range of environmental exposures, many CHMS variables remain underutilized. The CHMS dataset provides a valuable portrait of chemical exposures in Canadians of all ages, linked to a wide variety of health indicators. Many opportunities remain to exploit and expand both the use of the dataset and collaborations between Canadian agencies and domestic and international research institutions.

Full Breastfeeding and Obesity in Children: A Prospective Study from Birth to 6 Years

BACKGROUND

Obesity is a major public health crisis among both children and adults and contributes to significant physical, psychological, and economic burden. We aim to investigate the effect of duration of breastfeeding on excessive weight and obesity at 6 years of age.

SUBJECTS/METHODS

Data on breastfeeding and child anthropometric measurements were collected in a birth-cohort study in Murcia, Spain (n = 350). Breastfeeding status and body mass index (BMI) were established according to WHO definitions. Other factors potentially related to children's weight were considered. Multiple log-linear and ordinal regressions were used to analyze the effects of breastfeeding on overweight and obesity when considering potential confounders.

RESULTS

33% and 17.3% of children in the study were of excess weight and obesity, respectively. Univariate predictors of BMI in children aged 6 were as follows: pregestational maternal BMI (kg/m2) (R2 = 0.127, p < 0.01); full breastfeeding (weeks) R2 = -0.035, p < 0.01); infant weight gain (kg) (R2 = 0.348, p < 0.01); and maternal alcohol consumption during pregnancy (g/day) (R2 = 0.266, p < 0.01) at age 6. In the ordinal logistic regression, full breastfeeding was associated with a significant decrease in obesity -0.052 (95% CI, -0.10 to -0.003).

CONCLUSIONS

The delay of bottle feeding introduction may have a protective effect against obesity at 6 years of age. Our findings reinforce the need for greater support of breastfeeding and to promote a healthy environment and antipoverty interventions during pregnancy and infancy, alongside other strategies for obesity prevention.

A Home Visiting Parenting Program and Child Obesity: A Randomized Trial

BACKGROUND

Young children living in historically marginalized families are at risk for becoming adolescents with obesity and subsequently adults with increased obesity-related morbidities. These risks are particularly acute for Hispanic children. We hypothesized that the prevention-focused, socioecological approach of the "Minding the Baby" (MTB) home visiting program might decrease the rate of childhood overweight and obesity early in life.

METHODS

This study is a prospective longitudinal cohort study in which we include data collected during 2 phases of the MTB randomized controlled trial. First-time, young mothers who lived in medically underserved communities were invited to participate in the MTB program. Data were collected on demographics, maternal mental health, and anthropometrics of 158 children from birth to 2 years.

RESULTS

More children in the intervention group had a healthy BMI at 2 years. The rate of obesity was significantly higher (P < .01) in the control group (19.7%) compared with the intervention group (3.3%) at this age. Among Hispanic families, children in the MTB intervention were less likely to have overweight or obesity (odds ratio = 0.32; 95% confidence interval: 0.13-0.78).

CONCLUSIONS

Using the MTB program, we significantly lowered the rate of obesity among 2-year-old children living in low-socioeconomic-status communities. In addition, children of Hispanic mothers were less likely to have overweight or obesity at 2 years. Given the high and disproportionate national prevalence of Hispanic young children with overweight and obesity and the increased costs of obesity-related morbidities, these findings have important clinical, research, and policy implications.

Chemical and non-chemical stressors affecting childhood obesity: a systematic scoping review

Childhood obesity in the United States has doubled over the last three decades and currently affects 17% of children and adolescents. While much research has focused on individual behaviors impacting obesity, little research has emphasized the complex interactions of numerous chemical and non-chemical stressors found in a child's environment and how these interactions affect a child's health and well-being. The objectives of this systematic scoping review were to (1) identify potential chemical stressors in the context of non-chemical stressors that impact childhood obesity; and, (2) summarize our observations for chemical and non-chemical stressors in regards to child-specific environments within a community setting. A review was conducted to identify chemical and non-chemical stressors related to childhood obesity for the childhood life stages ranging from prenatal to adolescence. Stressors were identified and grouped into domains: individual behaviors, family/household behaviors, community stressors, and chemical exposures. Stressors were related to the child and the child's everyday environments and used to characterize child health and well-being. This review suggests that the interactions of chemical and non-chemical stressors are important for understanding a child's overall health and well-being. By considering these relationships, the exposure science research community can better design and implement strategies to reduce childhood obesity.

A scoping review of epidemiologic risk factors for pediatric obesity: Implications for future childhood obesity and dental caries prevention research

RESEARCH QUESTIONS

What are the non-modifiable (socioeconomic, genetic) and modifiable factors (physical activity, dietary behaviors) related to childhood (under age 12) obesity? How can this knowledge be applied to oral health professionals' efforts to prevent or manage dental caries in children?

OBJECTIVES

Studies have identified risk factors for childhood obesity. The purpose of this scoping review was to develop a conceptual model to identify non-modifiable and modifiable risk factors for childhood obesity and to illustrate how these findings are relevant in developing interventions aimed at preventing obesity and dental caries in children.

METHODS

The authors searched PubMed and Embase and limited the study to English-language publications. A total of 2,572 studies were identified. After de-duplication, 2,479 studies remained and were downloaded into a citation-management tool. Two authors screened the titles and abstracts for relevance. Two hundred and sixty studies remained and were retrieved for a full-text review, and 80 studies were excluded, resulting in 180 studies included in the scoping review. An inductive content analytic methods was used to organize all statistically significant obesity risk factors into seven domains, which were classified as non-modifiable or modifiable; then a conceptual model of common risk factors associated with childhood obesity and dental caries was developed.

RESULTS

Non-modifiable obesity risk factors include biological and developmental (e.g., genes, developmental conditions, puberty), sociodemographic and household (e.g., race/ethnicity, socioeconomic status, parent education, unemployment), cultural (e.g., degree of acculturation), and community (e.g., neighborhood composition). Modifiable risk factors included behavioral (e.g., diet, physical activity, weight), psychosocial (e.g., maternal stress, family functioning, parenting practices, child temperament), and medical (e.g., parent smoking, maternal health, child health).

CONCLUSIONS

Identifying common risk factors has important implications for future oral health research aimed at preventing childhood obesity and dental caries. Epidemiologic knowledge gleaned from the literature can be used to develop rigorous interventions and programs aimed at preventing these highly prevalent diseases and improving health outcomes for children.

Status report -- Childhood overweight and obesity in Canada: an integrative assessment

INTRODUCTION

Obesity is a complex risk factor for chronic disease that is associated with a number of socioecological determinants. In this status report, we provide an overview of the socioecological framework that is now guiding our ongoing surveillance efforts in the area of childhood overweight and obesity. This framework considers individual risk and protective factors (sociodemographic, lifestyle, psychosocial and early-life) through the lens of the life stage, levels of influence and environments in which these factors play a role.

METHODS

Using data from the Canadian Community Health Survey and the Canadian Health Measures Survey, univariate and bivariate analyses were used to report on behavioural, psychosocial, and early life factors associated with excess weight among Canadian children.

RESULTS

Estimates of early-life (e.g. breastfeeding), behavioural (e.g. physical activity), and psychosocial factors (e.g. sense of community) are presented as they relate to age group, sex, income adequacy and weight status.

CONCLUSION

Building upon our recent reporting on trends in and sociodemographic factors associated with childhood obesity in Canada, this work illustrates the remaining risk and protective factors shown in our surveillance framework. This analysis supports the shift towards a holistic appraisal of determinants related to healthy weights.

Systematic review and meta-analysis of the association between maternal smoking in pregnancy and childhood overweight and obesity

BACKGROUND

By 2020, it is predicted that 60 million children worldwide will be overweight. Maternal smoking in pregnancy has been suggested as a contributing factor. Our objective was to systematically review studies on this, thereby expanding the evidence base for this association.

METHODS

Systematic review with meta-analysis, Prospero Registration number CRD42012002859. We searched PubMed, Embase, Global Health, Web of Science and the Grey literature. We included prevalence, cohort and cross-sectional studies involving full-term, singleton pregnancies. Published and unpublished studies through to 1 January 2015 in all languages, demonstrating an objective overweight outcome up until 18 years of age and data presented as an OR, were included. Quality assessment was undertaken using an adaption of the Newcastle-Ottawa scale. Statistical analysis was performed using Review Manager V.5.3.

FINDINGS

The meta-analysis included 39 studies of 236 687 children from Europe, Australia, North America and South America and Asia. Maternal smoking in pregnancy ranged from 5.5% to 38.7%, with the prevalence of overweight from 6.3% to 32.1% and obesity from 2.6% to 17%. Pooled adjusted ORs demonstrated an elevated odds of maternal smoking in pregnancy for childhood overweight (OR 1.37, 95% CI 1.28 to 1.46, I₂ 45%) and childhood obesity (OR 1.55, 95% CI 1.40 to 1.73, I₂ 24%).

INTERPRETATION

Our results demonstrate an association between maternal prenatal smoking and childhood overweight. This contributes to the growing evidence for the aetiology of childhood overweight, providing important information for policymakers and health professionals alike in planning cessation programmes or antismoking interventions for pregnant female smokers.

Effectiveness of the gold standard programmes (GSP) for smoking cessation in pregnant and non-pregnant women

Background: Smoking is considered the most important preventable risk factor in relation to the development of complications during pregnancy and delivery. The aim of this study was to evaluate the effectiveness of an intensive 6-week gold standard programme (GSP) on pregnant women in real life. Methods: This was a prospective cohort study based on data from a national Danish registry on smoking cessation interventions. The study population included 10,682 women of a fertile age. The pregnancy status of the study population was identified using the National Patient Registry. Results: The response rate to follow up was 76%. The continuous abstinence rate for both pregnant and non-pregnant smokers was 24–32%. The following prognostic factors for continuous abstinence were identified: programme format (individual/group), older age, heavy smoking, compliance with the programme, health professional recommendation, and being a disadvantaged smoker. Conclusions: The GSP seems to be as effective among pregnant smokers as among non-pregnant smoking women. Due to the relatively high effect and clinical significance, the GSP would be an attractive element in smoking cessation intervention among pregnant women.

The methylation of the LEPR/LEPROT genotype at the promoter and body regions influence concentrations of leptin in girls and BMI at age 18 years if their mother smoked during pregnancy

To determine whether DNA methylation (DNA-M) of the leptin receptor genotype (LEPR/LEPROT) links gestational smoking and leptin serum levels and BMI later in life, we focused on female offspring, 18 years of age, from the Isle of Wight Birth Cohort (IOWBC). Leptin binds to the leptin receptor encoded by the LEPR/LEPROT genotype. Using general linear models, we tested a two-stage model. First, we investigated whether single nucleotide polymorphisms (SNPs) acting as methylation quantitative trait loci (methQTLs) depending on gestational smoking were related to differentially methylated cytosine-phosphate-guanine (CpG) sites. In stage 2, we tested whether the selected CpG sites, in interaction with other SNPs (modifiable genetic variants, modGV), are associated with serum leptin and BMI (stage 2). Children from the IOWBC were followed from birth to age 18. Information on gestational smoking was gathered upon delivery. SNPs tagging LEPR and LEPROT genes were genotyped. Data on LEPR/LEPROTDNA-M and leptin were obtained from blood samples drawn at age 18; to determine BMI, height and weight were ascertained. Blood samples were provided by 238 girls. Of the 21 CpG sites, interactions between gestational smoking and SNPs were detected for 16 CpGs. Methylation of seven of the 16 CpGs were, in interaction with modGVs, associated with leptin levels at age 18 years. Two CpGs survived a multiple testing penalty and were also associated with BMI. This two-stage model may explain why maternal smoking has a long-term effect on leptin levels and BMI in girls at age 18 years.