Higher Childhood Body Mass Index Research Articles

Childhood obesity and multiple sclerosis: A Mendelian randomization study

Background: Higher childhood body mass index (BMI) has been associated with an increased risk of multiple sclerosis (MS). Objective: To evaluate whether childhood BMI has a causal influence on MS, and whether this putative effect is independent from early adult obesity and pubertal timing. Methods: We performed Mendelian randomization (MR) using summary genetic data on 14,802 MS cases and 26,703 controls. Large-scale genome-wide association studies provided estimates for BMI in childhood (n = 47,541) and adulthood (n = 322,154). In multivariable MR, we examined the direct effects of each timepoint and further adjusted for age at puberty. Findings were replicated using the UK Biobank (n = 453,169). Results: Higher genetically predicted childhood BMI was associated with increased odds of MS (odds ratio (OR) = 1.26/SD BMI increase, 95% confidence interval (CI): 1.07–1.50). However, there was little evidence of a direct effect after adjusting for adult BMI (OR = 1.03, 95% CI: 0.70–1.53). Conversely, the effect of adult BMI persisted independent of childhood BMI (OR = 1.43; 95% CI: 1.01–2.03). The addition of age at puberty did not alter the findings. UK Biobank analyses showed consistent results. Sensitivity analyses provided no evidence of pleiotropy. Conclusion: Genetic evidence supports an association between childhood obesity and MS susceptibility, mediated by persistence of obesity into early adulthood but independent of pubertal timing.

Risk of gestational diabetes mellitus in nulliparous women – Associations with early life body size and change in body mass index from childhood to adulthood

AimsWe examined whether a woman’s birthweight, childhood height, body mass index (BMI), and BMI changes from childhood to pregnancy were associated with risks of gestational diabetes mellitus (GDM). MethodsWe studied 13,031 women from the Copenhagen School Health Records Register born 1959–1996 with birthweight and measured anthropometric information at ages 7 and/or 13. The diagnosis of GDM (n = 255) was obtained from a national health register. Risk ratios (RR) were estimated using log-linear binomial regression. ResultsOwn birthweight and childhood height were inversely associated with GDM. Girls with overweight at age 7 had a higher risk of GDM than girls with normal-weight (RR: 1.79, 95% CI: 1.31, 2.47). Compared to women with normal-weight in childhood and adulthood, risks of GDM were higher in women who developed overweight from age 7 to pregnancy (RR: 4.62; 3.48, 6.14) or had overweight at both times (RR: 4.71; 3.24, 6.85). In women whose BMI normalized from age 7 to pregnancy the RR for GDM was 1.08 (0.47, 2.46). ConclusionsLower birthweight, shorter childhood height, and higher childhood BMI are associated with increased risks of GDM. Efforts to help girls maintain a normal BMI before pregnancy may be warranted to minimize risks of GDM.

The pubertal growth spurt is diminished in children with severe obesity.

At the population level, there is a negative linear correlation between childhood body mass index (BMI) and pubertal height gain. However, in children with obesity, there are no studies showing whether the severity of obesity affects pubertal height gain. Moreover, how obesity in childhood affects pubertal timing is controversial, especially in boys. We aimed to investigate the impact of severe obesity in childhood on the pubertal growth spurt in both sexes. The study group consisted of 68 patients (32 boys) with childhood onset obesity followed in a Spanish university hospital. The QEPS growth model was used to calculate pubertal growth function estimates for each individual. The highest individual prepubertal BMI SDS value was related to the age at onset of pubertal growth and pubertal height gain. Results were compared to analyses from individuals in a community-based setting (n = 1901) with different weight status. A higher peak BMI in childhood was associated with less specific pubertal height gain in children with moderate-to-extreme obesity. For boys, the higher the BMI, the earlier the onset of pubertal growth. For girls with obesity, this correlation was not linear. Obesity in childhood impairs the pubertal growth spurt in a severity-related fashion. The higher the BMI in childhood, the lower the pubertal height gain in children with moderate-to-extreme obesity. For boys with obesity, the higher the BMI, the earlier the onset of pubertal growth. The results contribute to the research field of how weight status in childhood is related to pubertal timing and pubertal growth. The results have implications for understanding how childhood obesity is related to further growth.

Multilevel prenatal socioeconomic determinants of Mexican American children's weight: Mediation by breastfeeding.

Objective: Mexican American (MA) children are more likely to grow up in poverty than their non-Hispanic/Latinx white peers and are at an elevated risk for early onset obesity. The current study evaluated the effects of prenatal family- and neighborhood-level disadvantage on children's weight and weight gain from 12 months through 4.5 years of age. Maternal breastfeeding duration was evaluated as a potential mechanism underlying the relation between multilevel disadvantage and weight. Methods: Data was collected from 322 low-income, MA mother-child dyads. Women reported the degree of family socioeconomic disadvantage and breastfeeding status. Neighborhood disadvantage was evaluated with census-level metrics. Children's weight and height were measured at laboratory visits. Results: Greater prenatal neighborhood disadvantage predicted higher child Body Mass Index (BMI) at 12 months, over and above family-level disadvantage; this effect remained stable through 4.5 years. Breastfeeding duration partially mediated the effect of neighborhood disadvantage on child BMI. Breastfeeding duration predicted child BMI at all timepoints. Conclusions: Maternal prenatal residence in a neighborhood with high concentrated disadvantage may place low-income, MA children at increased risk of elevated weight status during the first few years of life. Breastfeeding duration emerged as potentially modifiable pathway through which the prenatal neighborhood impacts children's early life weight. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Overweight in childhood of exclusively breastfed infants with a high weight at 5 months.

High infant weight increases the risk of childhood overweight, while breastfeeding may reduce the risk. However, some infants have a very high weight gain even though they are exclusively breastfed. We examined the risk of a high body mass index (BMI) and overweight in childhood for infants ≥2.5 SD above the median weight‐for‐age (WAZ) at age 5 months according to duration of exclusive breastfeeding (≤2, >2 to <4 or ≥4 months). The study is based on 13,401 7‐year‐old and 9,819 11‐year‐old children enrolled into the Danish National Birth Cohort (born 1997–2003). Linear and logistic regression analyses were used to examine the associations while adjusting for presumed confounders including birth weight. The results showed that infants ≥2.5 SD at 5 months, breastfed exclusively ≤2, >2 to <4 or ≥4 months had adjusted odds ratios (ORs) for overweight at age 7 at 3.67 (95% confidence interval [CI] [2.10, 6.43]), 3.42 (95% CI [2.32, 5.04]) and 3.19 (95% CI [1.90, 5.36]) respectively, when compared with infants <2.5 SD WAZ exclusively breastfed ≥4 months. The corresponding results for BMI z‐scores were 0.82 (95% CI [0.60, 1.04]), 0.63 (95% CI [0.48, 0.78]) and 0.57 (95% CI [0.38, 0.77]). For the ≥2.5 SD infants, the differences in risk of overweight and BMI according to duration of exclusive breastfeeding were neither significantly different among the 7‐year nor among the 11‐year‐old children. A high infant weight increases the odds of overweight and is associated with a higher BMI in childhood. Whereas the odds and BMI z‐scores tended to be lower for those exclusively breastfed longer, the differences were not statistically significant.

Higher Child Body Mass Index Is Associated with Greater School-Based Health Center Utilization.

Background: Children with overweight status and obesity seek care for acute illnesses more often than normal weight peers. School-based health centers (SBHCs) have a role in acute and chronic disease management; however, little is known about SBHC use by children with overweight status and obesity. This study compared SBHC utilization by student body mass index (BMI) category and investigated whether SBHC visit diagnoses varied by BMI category. Methods: We performed a retrospective analysis of students (n = 1161) in grades K-8 enrolled in a large SBHC for 2 years. Negative binomial regression models were used to test the independent association between BMI category as defined by BMI percentile [normal/underweight (BMI percentile <85%) and overweight/obesity (BMI percentile ≥85%), either overweight (85% ≤BMI percentile <95%) or obesity (BMI percentile ≥95%)], and the number of SBHC visits (nurse, clinician, and total visits) for the 2-year interval. Top five diagnoses based on ICD-10 visit codes were compared. Results: Students in the overweight/obesity category (BMI percentile ≥85%) had higher visit rates than normal/underweight peers after adjusting for age and gender, but only total visits were statistically significant [nurse: incident rate ratio (IRR) 1.42 (95% CI 0.94-2.15); clinician: 1.27 (95% CI 0.93-1.75); total: 1.45 (95% CI 1.02-2.07)]. Visit diagnoses were similar by BMI category. Conclusions: Students with higher BMI percentiles, categorized as overweight/obesity, had higher SBHC utilization than normal/underweight peers, but visit diagnoses were similar. This higher utilization may provide an as-yet untapped opportunity to expand school-based obesity prevention and management.

Early-Life Environmental Exposures and Childhood Obesity: An Exposome-Wide Approach.

Background:Chemical and nonchemical environmental exposures are increasingly suspected to influence the development of obesity, especially during early life, but studies mostly consider single exposure groups.Objectives:Our study aimed to systematically assess the association between a wide array of early-life environmental exposures and childhood obesity, using an exposome-wide approach.Methods:The HELIX (Human Early Life Exposome) study measured child body mass index (BMI), waist circumference, skinfold thickness, and body fat mass in 1,301 children from six European birth cohorts age 6–11 y. We estimated 77 prenatal exposures and 96 childhood exposures (cross-sectionally), including indoor and outdoor air pollutants, built environment, green spaces, tobacco smoking, and biomarkers of chemical pollutants (persistent organic pollutants, metals, phthalates, phenols, and pesticides). We used an exposure-wide association study (ExWAS) to screen all exposure–outcome associations independently and used the deletion-substitution-addition (DSA) variable selection algorithm to build a final multiexposure model.Results:The prevalence of overweight and obesity combined was 28.8%. Maternal smoking was the only prenatal exposure variable associated with higher child BMI (z-score increase of 0.28, 95% confidence interval: 0.09, 0.48, for active vs. no smoking). For childhood exposures, the multiexposure model identified particulate and nitrogen dioxide air pollution inside the home, urine cotinine levels indicative of secondhand smoke exposure, and residence in more densely populated areas and in areas with fewer facilities to be associated with increased child BMI. Child blood levels of copper and cesium were associated with higher BMI, and levels of organochlorine pollutants, cobalt, and molybdenum were associated with lower BMI. Similar results were found for the other adiposity outcomes.Discussion:This first comprehensive and systematic analysis of many suspected environmental obesogens strengthens evidence for an association of smoking, air pollution exposure, and characteristics of the built environment with childhood obesity risk. Cross-sectional biomarker results may suffer from reverse causality bias, whereby obesity status influenced the biomarker concentration. https://doi.org/10.1289/EHP5975

Maternal practices and perceptions of child body mass status explain child energy expenditure behaviors and body mass

This study investigated whether maternal perceptions of child body mass status would predict child body mass index (BMI) z-score via two sets of sequential mediators: (1) four maternal practices promoting child energy expenditure and (2) children’s energy expenditure behaviors. The data of N = 729 mother–child dyads were collected at baseline [T1; n = 495 at 7- to 8-month follow-up (T2)]. Mothers reported perceptions of child body mass status and maternal practices (T1); children reported sedentary screen use and physical activity (T1, T2). Child body mass was assessed objectively (T1, T2). Higher stimulation to be active (T1) was related to a lower child BMI z-score (T2) via higher levels of child physical activity (T2). Higher levels of monitoring of screen use (T1) were associated with higher child BMI z-score (T2) via lower levels of child physical activity (T2). Encouraging parents to stimulate their children to be active may be beneficial for children’s weight maintenance.

Life Course Adiposity and Amyotrophic Lateral Sclerosis: A Mendelian Randomization Study.

Observational studies have indicated that life course adiposity is associated with amyotrophic lateral sclerosis (ALS). However, whether such an association reflects causality remains unclear. We aimed to determine whether life course adiposity such as birth weight (BW), childhood body mass index (BMI), adult BMI, body fat percentage (BF%), and waist-to-hip ratio (WHR) have causal effects on ALS. Single nucleotide polymorphisms (SNPs) significantly associated with life course adiposity were used as instrumental variables to estimate the causal effects on ALS. We used summary-level data from a cohort of 20,806 cases and 59,804 controls in a Mendelian randomization (MR) framework. Genetically predicted one standard deviation (1-SD) increase in BF% was associated with lower risk of ALS (odds ratio [OR] = 0.67, 95% confidence interval [CI] = 0.54-0.83, p = 3.25E-04) after Bonferroni correction (p < 0.05/5). Genetically predicted 1-SD higher childhood BMI was suggestively associated with lower risk of ALS (OR = 0.88, 95% CI = 0.78-0.99, p = 0.031). The weighted median method indicated a suggestive association between BMI and ALS (OR = 0.86, 95% CI = 0.69-0.96, p = 0.016). Neither a genetically predicted 1-SD increase in BW (inverse variance weighted [IVW]: OR = 1.01, 95% CI = 0.87-1.17, p = 0.939) nor WHR adjusted for BMI (IVW: OR = 0.90, 95% CI = 0.76-1.05, p = 0.178) was associated with ALS. Our findings provide novel evidence supporting a causal role of higher adiposity, taken as a whole, on lower risk of ALS. A deeper understanding of the energy metabolism of ALS is more likely to identify feasible nutritional interventions and even novel therapeutic targets that might improve the survival of ALS patients. Ann Neurol 2020;87:434-441.

Altered growth trajectory in children born to mothers with gestational diabetes mellitus and preeclampsia.

Gestational diabetes mellitus (GDM) and preeclampsia are leading causes of mortality and morbidity in mothers and children. High childhood body mass index (BMI) is among their myriad of negative outcomes. However, little is known about the trajectory of the child BMI exposed to GDM and co-occurring preeclampsia from early to mid-childhood. This study examined the independent and joint impact of GDM and preeclampsia on childhood BMI trajectory. A population-based sample of 356 mothers were recruited from OB/GYN clinics in New York. Their children were then followed annually from 18 to 72months. Maternal GDM and preeclampsia status were obtained from medical records. Child BMI was calculated based on their height and weight at annual visits. Hierarchical Linear Modeling was used to evaluate the trajectories of child BMI exposed to GDM and preeclampsia. BMI trajectory by GDM decreased (t ratio = - 2.24, [Formula: see text]0.45, 95% CI - 0.05-0.95, p = 0.07), but the trajectory by preeclampsia increased over time (t ratio = 3.153,[Formula: see text]0.65, 95% CI 0.11-1.18, p = 0.002). Moreover, there was a significant interaction between the two (t ratio = -2.24, [Formula: see text]- 1.244, 95% CI 0.15-2.33, p = 0.02), such that the BMI of children born to mothers with both GDM and preeclampsia showed consistent increases over time. GDM and preeclampsia could be used as a marker for childhood obesity risk and the identification of a high-risk group, providing potential early intervention. These findings highlight the importance of managing obstetric complications, as an effective method of child obesity prevention.

Associations of maternal caffeine intake during pregnancy with abdominal and liver fat deposition in childhood.

SummaryBackgroundMaternal caffeine intake during pregnancy is associated with an increased risk of childhood obesity. Studies in adults suggest that caffeine intake might also directly affect visceral and liver fat deposition, which are strong risk factors for cardio‐metabolic disease.ObjectiveTo assess the associations of maternal caffeine intake during pregnancy with childhood general, abdominal, and liver fat mass at 10 years of age.MethodsIn a population‐based cohort from early pregnancy onwards among 4770 mothers and children, we assessed maternal caffeine intake during pregnancy and childhood fat mass at age 10 years.ResultsCompared with children whose mothers consumed <2 units of caffeine per day during pregnancy, those whose mothers consumed 4‐5.9 and ≥6 units of caffeine per day had a higher body mass index, total body fat mass index, android/gynoid fat mass ratio, and abdominal subcutaneous and visceral fat mass indices. Children whose mothers consumed 4‐5.9 units of caffeine per day had a higher liver fat fraction. The associations with abdominal visceral fat and liver fat persisted after taking childhood total body fat mass into account.ConclusionsHigh maternal caffeine intake during pregnancy was associated with higher childhood body mass index, total body fat, abdominal visceral fat, and liver fat. The associations with childhood abdominal visceral fat and liver fat fraction were independent of childhood total body fat. This suggests differential fat accumulation in these depots, which may increase susceptibility to cardio‐metabolic disease in later life.

Distinct patterns of socio-economic disparities in child-to-adolescent BMI trajectories across UK ethnic groups: A prospective longitudinal study.

SummaryBackgroundIn many high‐income countries, body mass index (BMI)/obesity levels are inversely associated with socio‐economic position (SEP). Little is known whether socio‐economic patterns in BMI trajectories throughout childhood differ by ethnicity, especially in the United Kingdom.ObjectivesTo investigate socio‐economic disparities in child‐to‐adolescent BMI trajectories and risks of overweight and obesity during adolescence across ethnic groups.MethodsMixed‐effects fractional polynomial and multinomial regression models were applied to estimate socio‐economic differences in BMI trajectories (3‐14 years) and risk of overweight/obesity at 14 years, respectively, in the UK Millennium Cohort Study (n = 15 996). Analysis was stratified by ethnicity.ResultPoverty was associated with higher BMI in children of White and South Asian origins, with a small difference at 3 years, which widened with age to 0.75 kg/m2 (95% CI, 0.59‐0.91) and 0.77 kg/m2 (0.26‐1.27) at 14 years for the White and South Asian groups, respectively. There was a reverse income‐BMI association in children of Black (African‐Caribbean) origin with the poverty group having a lower BMI (−0.37 kg/m2 [−0.71 to ‐0.04] at 5 years; −0.95 kg/m2 [−1.79 to −0.11] at 14 years). These patterns also presented with maternal education as a SEP indicator and for obesity at 14 years.ConclusionsSocio‐economic advantage may not be universally associated with lower BMI, which should be considered when planning obesity interventions. The positive SEP‐BMI association in children of Black origin requires replication and merits further investigation into underpinning mechanisms.

Phenome-Wide Investigation of the Causal Associations between Childhood BMI and Adult Outcomes Using Two-Sample Mendelian Randomization

Background: The causal effects of childhood obesity have not been systematically characterized. We aimed to assess the causal associations between childhood body mass index (BMI) and various adult traits/diseases using two-sample Mendelian randomization (MR). Methods: Over 5,000 datasets for adult outcomes were obtained from various resources. After data filtering, 269 adult traits genetically correlated with childhood BMI (P < 0.05) were subjected to MR analyses. The number of independent outcomes was 148, setting the significant threshold as P < 3.38 × 10-4. Inverse-variance weighted method, MR-Egger, weighted median method, and weighted mode method were used to estimate the causal effects. Findings: We identified potential causal effects of childhood obesity on 92 adult traits (48 disease-related traits, 35 lifestyle factors, and 9 other traits). Higher childhood BMI was associated with a reduced overall health rating (β = −0.10, 95% CI: −0.13 to −0.07, P = 6.26 × 10-11) and lower average total household income before tax (β = −0.0576, 95% CI: −0.0862 to −0.0291, P = 7.57 × 10 -5 ). Findings on diseases included some novel effects, such as the adverse effects of higher childhood BMI on venous thromboembolic disease (OR = 1.06, 95% CI: 1.03 to 1.09, P = 2.09 × 10 -4). For dietary habits, we found that higher childhood BMI was positively associated adult diet portion size (β = 0.26, 95% CI: 0.18 to 0.34, P= 7.34 × 10-11) and variation in diet (β = 0.06, 95% CI: 0.03 to 0.09, P = 3.15 × 10-5). The association between adulthood BMI and heel bone mineral density no longer existed after excluding the SNPs existing in or in linkage disequilibrium with childhood BMI. Network MR analyses suggested that past tobacco smoking, variation in diet and portion size mediated 6.39%, 3.29%, and 10.90% of the associations between childhood BMI and Type 2 Diabetes, respectively. Interpretation: In summary, childhood obesity is a risk factor for general health outcomes and socioeconomic status. The importance of control portion size and reduce dietary variation is noted. The positive association between adulthood BMI and heel BMD depend on childhood BMI. Our results highlight the need to intervene in childhood to reduce obesity from a young age and its later-life effects. Funding Statement: This study is supported by the National Natural Science Foundation of China: (31871264, 31701095); Natural Science Basic Research Program Shaanxi Province (2018JQ3058,); Innovative Talent Promotion Plan of Shaanxi Province for Young Sci-Tech New Star (2018KJXX-010), the Fundamental Research Funds for the Central Universities. This work was also supported by the high performance computing platform of Xi’an Jiaotong University. Declaration of Interests: All authors declare no competing interests. Ethics Approval Statement: All data are publicly available through data resources indicated in the methods.

Development of the Highly Processed Food Withdrawal Scale for Children

IntroductionHighly processed foods (with added fats and/or refined carbohydrates) may trigger an addictive-like process, including withdrawal when these foods are reduced. Withdrawal is marked by affective, cognitive, and physical symptoms that may hinder dietary change. A recently developed scale of highly processed food withdrawal in adults (ProWS) provides evidence for this construct. Children commonly consume highly processed foods, but no measures currently exist to examine highly processed food withdrawal in children. The purpose of this study was to develop a measure (ProWS-C) to assess for signs of highly processed food withdrawal in children. MethodsParents who had recently attempted to reduce their child's highly processed food consumption were recruited through an online crowdsourcing platform. 304 parents (56.9% mothers) reported on their 3-11-year-old children (63.8% male). The ProWS-C was designed to reflect parents' observations of child behavior. Internal consistency and validity were evaluated using the Dimensional Yale Food Addiction Scale Version 2.0 for Children (dYFAS-C 2.0.), Children's Food Neophobia Scale-Modified (CFNS), and body mass index (BMI) silhouettes. ResultsExploratory factor analysis revealed a one-factor structure with 21 items (α = 0.94). The ProWS-C demonstrated convergent validity with more child food addiction symptoms (r = 0.55, p < 0.001) and higher child BMI (r = 0.24, p < 0.001) and discriminant validity with child food neophobia (r = −0.10, p = 0.08). The ProWS-C was associated with less success in reducing child highly processed food intake independent of child addictive-like eating and BMI (p = 0.001). DiscussionThe ProWS-C provides preliminary evidence for highly processed food withdrawal in children and appears to be a psychometrically sound tool for assessing parent-reported withdrawal symptoms in children. Illuminating specific challenges families face when reducing highly processed foods may improve parents’ ability to help their children make sustainable dietary changes.

Snack Portion Sizes for Preschool Children Are Predicted by Caregiver Portion Size, Caregiver Feeding Practices and Children's Eating Traits.

Caregivers are mostly responsible for the foods young children consume; however, it is unknown how caregivers determine what portion sizes to serve. This study examined factors which predict smaller or larger than recommended snack portion sizes in an online survey. Caregivers of children aged 2 to 4 years were presented with 10 snack images, each photographed in six portion sizes. Caregivers (n = 659) selected the portion they would usually serve themselves and their child for an afternoon snack. Information on child eating traits, parental feeding practices and demographics were provided by caregivers. Most caregivers selected portions in line with recommended amounts for preschool children, demonstrating their ability to match portion sizes to their child′s energy requirements. However, 16% of caregivers selected smaller than recommended low energy-dense (LED, e.g., fruits and vegetables) snacks for their child which was associated with smaller caregiver′s own portion size, reduced child food liking and increased satiety responsiveness. In contrast, 28% of caregivers selected larger than recommended amounts of high energy-dense (HED, e.g., cookies, crisps) snacks for their child which were associated with larger caregiver′s own portion size, greater frequency of consumption, higher child body mass index (BMI), greater pressure to eat and lower child food liking. These findings suggest that most caregivers in this study select portions adjusted to suit their child′s age and stage of development. Future interventions could provide support to caregivers regarding the energy and nutrient density of foods given the relatively small portion sizes of LED and large portions of HED snacks offered to some children.

Maternal Self-Efficacy Is Protective for Child (but Not Mother) Body Mass Index Among Mexican-Origin Children with Negative Temperament.

Childhood obesity persists as a serious public health concern, particularly among Mexican-origin youth. Teen mothers are also at heightened obesity risk. Multiple factors may exacerbate this risk, including stressors associated with parenting. Indeed, difficult child temperaments pose unique parenting challenges, which may also be linked to physical health outcomes in mothers. The purpose of this study was to examine whether the interaction between negative child temperament and parenting self-efficacy is related to the body mass index (BMI) of young children and their adolescent mothers while controlling for important contextual factors. We also examined which pathways differed for girls versus boys. Data were from a longitudinal study spanning 5 years that included 204 Mexican-origin young mothers and their children (with data collected at birth, age 4 years, and age 5 years). A multigroup structural equation modeling framework was used. The rate of early childhood obesity was low in comparison with national averages, whereas the rate of adolescent mother obesity was notably higher than the national average. Negative child temperament was associated with higher child BMI among those adolescent mothers with low parenting self-efficacy. Among the children with a negative temperament, their mothers' high parenting self-efficacy may have served as a protective factor against unhealthy child BMI. This significant interaction held for both boys and girls. Research evaluating the potential effectiveness of interventions that promote parenting self-efficacy during early childhood as a means to reduce the rate of obesity among children of adolescent mothers should be conducted.

Maternal age at menarche and offspring body mass index in childhood

BackgroundEarlier age of menarche has been associated with an increased risk of chronic diseases during adulthood, but whether early menarche has intergenerational effect is not clear.MethodsIn this population-based cross-sectional study, we recruited children from 26 primary schools using cluster random probability sampling in Shanghai, China, in 2014. We used multiple linear regression models to estimate the adjusted associations of maternal age of menarche (MAM) with offspring body mass index (BMI). We also used the mediation analysis to examine the contribution of maternal BMI and gestational diabetes to offspring BMI.ResultsA total of 17,571 children aged 6–13 years were enrolled, of whom 16,373 had their weight and height measured. Earlier MAM was associated with higher child BMI in boys (− 0.05 z-score per year older MAM, 95% CI − 0.08 to − 0.02) and in girls (− 0.05 z-score per year older MAM, 95% CI − 0.07 to − 0.02). Maternal BMI positively mediated the association of MAM with offspring BMI in both sexes, with mediation effects of 37.7 and 19.4% for boys and girls, respectively.ConclusionEarly maternal menarche was associated with greater offspring BMI. This study provides evidence for the intergenerational effect in the development of BMI in offspring.

Prenatal exposure to airborne polycyclic aromatic hydrocarbons and childhood growth trajectories from age 5–14 years

There is evidence that exposures to polycyclic aromatic hydrocarbons (PAH) and fine particles in air pollution are associated with higher childhood body mass index (BMI). Birth cohort analyses of prenatal exposures to PAH and child BMI Z-scores from age 5–14 years were conducted. African-American and Hispanic children born in the Bronx or Northern Manhattan, New York (1998–2006), whose mothers underwent personal air monitoring for airborne PAH exposure during pregnancy, were followed up with measurements of height and weight at approximate ages 5, 7, 9, 10, 11, 12.5 and 13.5 years. Multivariable generalized estimating equation analyses were used to relate prenatal airborne PAH exposures to child BMI Z-scores through time. The analyses adjusted for many known risk factors for childhood obesity and included interactions terms between age and exposure tertiles and age squared and exposure tertiles. In total, 535 children had at least one height and weight measure during follow-up. The prevalence of obesity was 20.6% at age 5 and increased across follow-ups until age 11 when it was 33.0%. At age 5, BMI Z-scores were significantly greater for children in the third tertile of exposure relative to the first tertile (0.35 Z-score units, 95% CI 0.09, 0.61, p = 0.007) and were non-significantly higher for the second tertile of exposure compared to the first tertile (0.25 Z-score units, 95% CI -0.02, 0.52, P = 0.075). The trajectories of BMI Z-scores by tertiles of exposure converged as the children aged, such that by age 11 years the estimated mean BMI Z-scores associated with each tertile of exposure were not different. Prenatal exposures to airborne PAH were associated with higher childhood BMI Z-scores at a young age, but growth trajectories converged by age 11 years. Accordingly, highly exposed children spend a greater proportion of their childhood with higher BMI Z-scores.

Maternal pre-pregnancy obesity and timing of puberty in sons and daughters: a population-based cohort study.

BackgroundIn many countries, an increased prevalence of obesity in pregnancy has coincided with a declining pubertal age. We aimed to explore the potential effect of maternal pre-pregnancy overweight and obesity on timing of puberty in sons and daughters.MethodsBetween 2012 and 2018, 15 819 of 22 439 invited children from the Danish National Birth Cohort, born 2000–03, provided half-yearly information from the age of 11 years on the pubertal milestones: Tanner stages, voice break, first ejaculation, menarche, acne and axillary hair. We estimated adjusted mean monthly differences (with 95% confidence intervals) in age at attaining the pubertal milestones for children exposed to maternal pre-pregnancy obesity [body mass index (BMI) ≥30.0 kg/m2] or overweight (BMI 25.0 to 29.9 kg/m2) with normal weight (BMI 18.5 to 24.9 kg/m2) as reference. In mediation analysis, we explored whether childhood BMI at age 7 years mediated the associations.ResultsMaternal pre-pregnancy obesity was associated with earlier age at attaining most pubertal milestones in sons, and pre-pregnancy overweight and obesity were associated with earlier age at attaining all pubertal milestones in daughters. When combining all pubertal milestones, pre-pregnancy obesity [sons: −1.5 (−2.5, −0.4) months; daughters: −3.2 (−4.2, −2.1) months] and overweight [daughters only: −2.6 (−3.3, −1.8) months] were associated with earlier timing of puberty. The associations in sons were completely mediated by higher childhood BMI and partly so in daughters.ConclusionsMaternal pre-pregnancy obesity appears to lower timing of puberty through childhood obesity in sons and mainly through other mechanisms in daughters.

Childhood Body Mass Index Is Associated with Risk of Adult Colon Cancer in Men: An Association Modulated by Pubertal Change in Body Mass Index.

The relative contribution of childhood and pubertal body mass index (BMI) for the risk of adult colorectal cancer is not known. The aim of this study was to evaluate the independent associations for childhood BMI and pubertal BMI change with risk of colorectal cancer in men. We included 37,663 men born in 1946 to 1961 who had weight and height measured at 8 (childhood) and 20 (young adult age) years of age available from the BMI Epidemiology Study. Information on colorectal cancer was retrieved from the Swedish National Patient Register (257 cases of colon cancer and 159 cases of rectal cancer). Childhood BMI at 8 years of age [HR, 1.19 per SD increase; 95% confidence interval (CI), 1.06-1.33], but not pubertal BMI change (HR, 1.02; 95% CI, 0.90-1.15), was associated with increased risk of colon cancer. Due to a significant interaction between childhood BMI and pubertal BMI change (P < 0.001), we stratified the analyses according to the median of pubertal BMI change. Childhood BMI was associated with risk of colon cancer in individuals with a pubertal BMI change above, but not below, the median (above: HR = 1.48, 95% CI, 1.26-1.74; below: HR = 0.95, 95% CI, 0.80-1.12). Neither childhood BMI nor pubertal BMI change was associated with rectal cancer. High childhood BMI was associated with increased risk of colon cancer only if it was followed by a pubertal BMI increase above the median. Further studies should evaluate prepubertal childhood BMI in relation to pubertal BMI change and BMI in middle age for the risk of colon cancer.