Perinatal and family factors associated with preadolescence overweight/obesity in Greece: the GRECO study

Association of Perinatal Factors and Family Sociodemographic Characteristics With Cardiometabolic Health in Pre-Adolescence: Cross-Sectional Results From Healthy Growth Study

AIM

Study the influence of a variety of perinatal factors on the presence of metabolic syndrome and its parameters in prepubertal age, considering socio-demographic factors, sex, Tanner stage and weight status of the preadolescent.

METHODS

Data collected from the cross-sectional Healthy Growth Study (2007) in students from four prefectures of Greece and their families. Cardiometabolic risk factors (waist circumference, blood pressure and blood indices) and perinatal data (from parents and health records) were collected. Single and a multiple logistic regression performed to assess the associations with cardiometabolic risk in preadolescence. Dependent variables included waist circumference, blood glucose, HDL-C, TG, blood pressure and metabolic syndrome presence, while independent variables encompassed perinatal factors categorised as pre-pregnancy, during and post-pregnancy.

RESULTS

2666 pre-adolescents (mean age 11.2 year) participated in the study. After adjustment for parental educational level, family income, sex, Tanner stage and weight category, maternal pre-pregnancy weight was positively associated with high waist circumference (OR, 95% CI 1.02 (1.00-1.04)), low HDL-C levels (OR, 95% CI 1.01 (1.00-1.03)) and metabolic syndrome (OR, 95% CI 1.02 (1.00-1.05)). Timing of solid foods' introduction was positively associated with high waist circumference (OR, 95% CI 1.09 (1.01-1.08)), gestational age with high glucose levels (OR, 95% CI 1.12 (1.04-1.19)), smoking (OR, 95% CI 1.07 (1.00-1.14)) and alcohol consumption (OR, 95% CI 2.35 (1.05-5.27)) during the first trimester of breastfeeding with high glucose levels and low HDL-C levels, respectively. Number of previous miscarriages was positively associated with low HDL-C levels (OR, 95% CI 1.28 (1.04-1.57)). Gestational age was negatively associated with high waist circumference (OR, 95% CI 0.87 (0.80-0.95)) and iron supplementation in the third pregnancy trimester negatively association with high TG levels (OR, 95% CI 0.34 (0.12-0.91)).

CONCLUSIONS

Maternal weight, perinatal behaviours, infant feeding and miscarriages influence pre-pubertal cardiometabolic health, independent of sociodemographics, sex, Tanner stage and weight.

Parental education associated with immune function in adolescence

BACKGROUND

The immune system is affected and shaped by several internal and external factors. Among the external variables, the socioeconomic status is known to influence the immune system since the early years of life and throughout life.

METHODS

In this study, we assessed the relationship between parental education with the white blood cells and its subtypes in 1213 adolescents from the EPITeen cohort, assessed at the age of 13. Beta coefficients (β) and 95% confidence intervals (CI) were fitted using linear regression models to quantify the association and were adjusted for sex, body mass index and chronic disease.

RESULTS

After adjustment, parental education presented a negative association with white blood cells, which was significant among those with higher high-sensitivity C-reactive protein (hs-CRP) median levels [-0.05 mg/l (95% CI -0.08, -0.01)]. On the contrary, a positive association with lymphocytes was observed, which was, significant among those with lower hs-CRP [0.17 mg/l (95% CI 0.02, 0.32)]. A neutrophil-to-lymphocyte ratio significant decrease was also observed with the increment of parental education (P<0.001).

CONCLUSION

We found that parental education was positively associated with a higher proportion of lymphocytes and a lower proportion of neutrophils, suggesting that parental education is associated with offsprinǵs innate immune system regulation. These results may contribute to clarify the relationships between childhood socioeconomic status and increased risk of adverse cardiovascular outcomes and other immune-related diseases.

Gestational weight gain, birthweight and early-childhood obesity: between- and within-family comparisons

BACKGROUND

Associations of excessive gestational weight gain (GWG) with greater birthweight and childhood obesity may be confounded by shared familial environment or genetics. Sibling comparisons can minimize variation in these confounders because siblings grow up in similar environments and share the same genetic predisposition for weight gain.

METHODS

We identified 96 289 women with live births in 2008-2014 at Kaiser Permanente Northern California. Fifteen percent of women (N = 14 417) had at least two births during the study period for sibling analyses. We assessed associations of GWG according to the Institute of Medicine (IOM) recommendations with birthweight and obesity at age 3 years, using conventional analyses comparing outcomes between mothers and sibling analyses comparing outcomes within mothers, which control for stable within-family unmeasured confounders such as familial environment and genetics. We used generalized estimating-equations and fixed-effects models.

RESULTS

In conventional analyses, GWG above the IOM recommendations was associated with 88% greater odds of large-for-gestational age birthweight [95% confidence interval (CI): 1.80, 1.97] and 30% greater odds of obesity at 3 years old (95% CI: 1.24, 1.37) compared with GWG within the IOM recommendations. In sibling analyses, GWG above the IOM recommendations was also associated with greater odds of large-for-gestational age [odds ratio (OR): 1.36; 95% CI: 1.20, 1.54], but was not associated with obesity at 3 years old (OR = 0.98; 95% CI: 0.84, 1.15).

CONCLUSIONS

GWG likely has a direct impact on birthweight; however, shared environmental and lifestyle factors within families may play a larger role in determining early-childhood weight status and obesity risk than GWG.

Association between maternal smoking during pregnancy and offspring overweight in U.S.-born children

BACKGROUND

The criticism of the literature on smoking during pregnancy and offspring overweight was the confounding from postnatal factors. Interaction between gestational age and prenatal maternal smoking has not yet assessed.

METHODS

We used the Third National Health and Nutrition Examination Survey (1988-1994), linked with natality files of US-born singletons aged 2 to 6 years. A body mass index in the 85th percentile or higher were considered overweight, including obesity. Gestational age was dichotomized as preterm (<37 weeks, n = 240) or full-term (n = 2125). Smoking status during pregnancy was ascertained by a questionnaire-based interview during National Health and Nutrition Examination Survey.

RESULTS

The prevalence of offspring overweight and obesity combined was 17.3% (SE = 1.3%). And 24.0% (1.3%) of mothers smoked while pregnant. A significant interaction was observed between maternal smoking and gestational age. In preterm children, a higher prevalence of overweight (34.3% [6.7%]) was found among the offspring of smoking mothers compared to non-smoking mothers (15.8% [3.6%]). After adjustment for socio-demographics, prenatal and postnatal factors, in preterm born offspring, the odds ratio of being born to smoking mothers was 2.46 (95% confidence intervals: 1.13-5.37) among children with overweight/obesity compared to children with healthy weight born to non-smoking mothers. In full-term children, the OR of being born to smoking mothers was 0.72 (0.50-1.03) among offspring with overweight/obesity relative to offspring with healthy weight born to non-smoking mothers.

CONCLUSIONS

Maternal smoking during pregnancy was strongly associated with offspring overweight and obesity in preterm births after control for postnatal factors. Preterm children of smoking mothers should be prioritized for obesity prevention.

The association between maternal body mass index and child obesity: A systematic review and meta-analysis

BACKGROUND

There is a global obesity crisis, particularly among women and disadvantaged populations. Early-life intervention to prevent childhood obesity is a priority for public health, global health, and clinical practice. Understanding the association between childhood obesity and maternal pre-pregnancy weight status would inform policy and practice by allowing one to estimate the potential for offspring health gain through channelling resources into intervention. This systematic review and meta-analysis aimed to examine the dose-response association between maternal body mass index (BMI) and childhood obesity in the offspring.

METHODS AND FINDINGS

Searches in MEDLINE, Child Development & Adolescent Studies, CINAHL, Embase, and PsycInfo were carried out in August 2017 and updated in March 2019. Supplementary searches included hand-searching reference lists, performing citation searching, and contacting authors. Two researchers carried out independent screening, data extraction, and quality assessment. Observational studies published in English and reporting associations between continuous and/or categorical maternal and child BMI or z-score were included. Categorical outcomes were child obesity (≥95th percentile, primary outcome), overweight/obesity (≥85th percentile), and overweight (85th to 95th percentile). Linear and nonlinear dose-response meta-analyses were conducted using random effects models. Studies that could not be included in meta-analyses were summarised narratively. Seventy-nine of 41,301 studies identified met the inclusion criteria (n = 59 cohorts). Meta-analyses of child obesity included 20 studies (n = 88,872); child overweight/obesity, 22 studies (n = 181,800); and overweight, 10 studies (n = 53,238). Associations were nonlinear and there were significantly increased odds of child obesity with maternal obesity (odds ratio [OR] 3.64, 95% CI 2.68-4.95) and maternal overweight (OR 1.89, 95% CI 1.62-2.19). Significantly increased odds were observed for child overweight/obesity (OR 2.69, 95% CI 2.10-3.46) and for child overweight (OR 1.80, 95% CI 1.25, 2.59) with maternal obesity. A limitation of this research is that the included studies did not always report the data in a format that enabled inclusion in this complex meta-analysis.

CONCLUSIONS

This research has identified a 264% increase in the odds of child obesity when mothers have obesity before conception. This study provides substantial evidence for the need to develop interventions that commence prior to conception, to support women of childbearing age with weight management in order to halt intergenerational obesity.

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.

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.

WHO European Childhood Obesity Surveillance Initiative: School nutrition environment and body mass index in primary schools

BACKGROUND

Schools are important settings for the promotion of a healthy diet and sufficient physical activity and thus overweight prevention.

OBJECTIVE

To assess differences in school nutrition environment and body mass index (BMI) in primary schools between and within 12 European countries.

METHODS

Data from the World Health Organization (WHO) European Childhood Obesity Surveillance Initiative (COSI) were used (1831 and 2045 schools in 2007/2008 and 2009/2010, respectively). School personnel provided information on 18 school environmental characteristics on nutrition and physical activity. A school nutrition environment score was calculated using five nutrition-related characteristics whereby higher scores correspond to higher support for a healthy school nutrition environment. Trained field workers measured children's weight and height; BMI-for-age (BMI/A) Z-scores were computed using the 2007 WHO growth reference and, for each school, the mean of the children's BMI/A Z-scores was calculated.

RESULTS

Large between-country differences were found in the availability of food items on the premises (e.g., fresh fruit could be obtained in 12%-95% of schools) and school nutrition environment scores (range: 0.30-0.93). Low-score countries (Bulgaria, Czech Republic, Greece, Hungary, Latvia and Lithuania) graded less than three characteristics as supportive. High-score (≥0.70) countries were Ireland, Malta, Norway, Portugal, Slovenia and Sweden. The combined absence of cold drinks containing sugar, sweet snacks and salted snacks were more observed in high-score countries than in low-score countries. Largest within-country school nutrition environment scores were found in Bulgaria, Czech Republic, Greece, Hungary, Latvia and Lithuania. All country-level BMI/A Z-scores were positive (range: 0.20-1.02), indicating higher BMI values than the 2007 WHO growth reference. With the exception of Norway and Sweden, a country-specific association between the school nutrition environment score and the school BMI/A Z-score was not observed.

CONCLUSIONS

Some European countries have implemented more school policies that are supportive to a healthy nutrition environment than others. However, most countries with low school nutrition environment scores also host schools with supportive school environment policies, suggesting that a uniform school policy to tackle the "unhealthy" school nutrition environment has not been implemented at the same level throughout a country and may underline the need for harmonized school policies.