The Intervention Nurses Start Infants Growing on Healthy Trajectories (INSIGHT) Responsive Parenting Intervention for Firstborns Affects Dietary Intake of Secondborn Infants

Methylation profiles at birth linked to early childhood obesity

Childhood obesity represents a significant global health concern and identifying its risk factors is crucial for developing intervention programs. Many "omics" factors associated with the risk of developing obesity have been identified, including genomic, microbiomic, and epigenomic factors. Here, using a sample of 48 infants, we investigated how the methylation profiles in cord blood and placenta at birth were associated with weight outcomes (specifically, conditional weight gain, body mass index, and weight-for-length ratio) at age six months. We characterized genome-wide DNA methylation profiles using the Illumina Infinium MethylationEpic chip, and incorporated information on child and maternal health, and various environmental factors into the analysis. We used regression analysis to identify genes with methylation profiles most predictive of infant weight outcomes, finding a total of 23 relevant genes in cord blood and 10 in placenta. Notably, in cord blood, the methylation profiles of three genes (PLIN4, UBE2F, and PPP1R16B) were associated with all three weight outcomes, which are also associated with weight outcomes in an independent cohort suggesting a strong relationship with weight trajectories in the first six months after birth. Additionally, we developed a Methylation Risk Score (MRS) that could be used to identify children most at risk for developing childhood obesity. While many of the genes identified by our analysis have been associated with weight-related traits (e.g., glucose metabolism, BMI, or hip-to-waist ratio) in previous genome-wide association and variant studies, our analysis implicated several others, whose involvement in the obesity phenotype should be evaluated in future functional investigations.

Spillover effects of childhood obesity prevention interventions: A systematic review

BACKGROUND

Childhood obesity prevention initiatives are complex interventions that aim to improve children's obesity-related behaviors and provide health promoting environments. These interventions often impact individuals, communities, and outcomes not primarily targeted by the intervention or policy. To accurately capture the effectiveness and cost-effectiveness of childhood obesity prevention interventions, an understanding of the broader impacts (or spillover effects) is required. This systematic review aims to assess the spillover effects of childhood obesity prevention interventions.

METHODS

Six academic databases and two trial registries were searched (2007-2023) to identify studies reporting quantifiable obesity-related and other outcomes in individuals or communities not primarily targeted by an obesity prevention intervention. Critical appraisal was undertaken for studies that reported statistically significant findings, and a narrative synthesis of the data was undertaken.

RESULTS

Twenty academic studies and 41 trial records were included in the synthesis. The most commonly reported spillovers were diet or nutrition-related, followed by BMI and physical activity/sedentary behavior. Spillovers were mostly reported in parents/caregivers followed by other family members. Nine of the 20 academic studies reported statistically significant spillover effects.

CONCLUSION

Limited evidence indicates that positive spillover effects of childhood obesity prevention interventions can be observed in parents/caregivers and families of targeted participants.

Methylation profiles at birth linked to early childhood obesity

Childhood obesity represents a significant global health concern and identifying risk factors is crucial for developing intervention programs. Many 'omics' factors associated with the risk of developing obesity have been identified, including genomic, microbiomic, and epigenomic factors. Here, using a sample of 48 infants, we investigated how the methylation profiles in cord blood and placenta at birth were associated with weight outcomes (specifically, conditional weight gain, body mass index, and weight-for-length ratio) at age six months. We characterized genome-wide DNA methylation profiles using the Illumina Infinium MethylationEpic chip, and incorporated information on child and maternal health, and various environmental factors into the analysis. We used regression analysis to identify genes with methylation profiles most predictive of infant weight outcomes, finding a total of 23 relevant genes in cord blood and 10 in placenta. Notably, in cord blood, the methylation profiles of three genes (PLIN4, UBE2F, and PPP1R16B) were associated with all three weight outcomes, which are also associated with weight outcomes in an independent cohort suggesting a strong relationship with weight trajectories in the first six months after birth. Additionally, we developed a Methylation Risk Score (MRS) that could be used to identify children most at risk for developing childhood obesity. While many of the genes identified by our analysis have been associated with weight-related traits (e.g., glucose metabolism, BMI, or hip-to-waist ratio) in previous genome-wide association and variant studies, our analysis implicated several others, whose involvement in the obesity phenotype should be evaluated in future functional investigations.

Effects of a Parenting and Nutrition Intervention on Siblings: A Cluster-RCT

OBJECTIVES

The majority of the evidence about the effectiveness of early parenting and nutrition interventions pertains to 1 targeted index child in a given household. We evaluated whether nontargeted sibling children benefited from a bundled parenting and nutrition intervention.

METHODS

We designed a sub-study within a broader cluster-randomized trial that evaluated the effects of engaging both mothers and fathers and bundling parenting and nutrition interventions in Mara, Tanzania. Trained community health workers delivered interventions to parents through peer groups and home visits. Interventions encompassed various content including responsive parenting, infant and young child feeding, and positive couples' relationships. The main trial enrolled mothers and fathers and 1-index children <18 months of age in 80 clusters. Between June and July 2021, in 32 clusters (16 intervention, 16 control), we reenrolled 222 households (118 intervention, 104 control) from the main trial that had another child <6 years of age (ie, sibling to the index child). We compared caregiving practices and child development and nutrition outcomes among siblings in intervention versus control households.

RESULTS

Compared with control siblings, intervention siblings had improved expressive language development (β = 0.33 [95% confidence interval: 0.03 to 0.62]) and dietary intake (β = 0.52 [0.10 to 0.93]) and reduced internalizing behaviors (β = -0.56 [-1.07 to -0.06]). Intervention caregivers reported greater maternal stimulation (β = 0.31 [0.00 to 0.61]) and paternal stimulation (β = 0.33 [0.02 to 0.65]) and displayed more responsive caregiving behaviors (β = 0.40 [0.09 to 0.72]) with sibling children.

CONCLUSIONS

A father-inclusive, bundled parenting and nutrition intervention can achieve positive spillover effects on sibling children's developmental and nutritional outcomes.

'I'm having jelly because you've been bad!': A grounded theory study of mealtimes with siblings in Australian families

Obesity prevention interventions have been designed to promote responsive feeding in early childhood. However, existing interventions primarily target first-time mothers without considering the complexities of feeding multiple children within a family unit. By applying principles of Constructivist Grounded Theory (CGT), this study aimed to explore how mealtimes are enacted in families with more than one child. A mixed-methods study was conducted with parent-sibling triads (n = 18 families) in South East Queensland, Australia. Data included direct mealtime observations, semistructured interviews, field notes, and memos. Data were analysed using open and focused coding, during which constant comparative analysis was applied. The sample comprised of two-parent families with children ranging in age from 12 to 70 months (median sibling age difference = 24 months). A conceptual model was developed to map sibling-related processes integral to the enactment of mealtimes in families. Notably, this model captured feeding practices used by siblings, such as pressure to eat and overt restriction, that previously had only been described in parents. It also documented feeding practices used by parents that may occur only in the presence of a sibling, such as leveraging sibling competitiveness and rewarding a child to vicariously condition their sibling's behaviour. The conceptual model demonstrates complexities in feeding that give shape to the overall family food environment. Findings from this study can inform the design of early feeding interventions that support parents to remain responsive, particularly when their perceptions and expectations of siblings differ.

Effect of the INSIGHT Firstborn Parenting Intervention on Secondborn Sleep

BACKGROUND AND OBJECTIVES

The Intervention Nurses Start Infants Growing on Healthy Trajectories (INSIGHT) responsive parenting (RP) intervention for first-time mothers improved firstborn infant sleep compared with controls. The goals of this analysis were to test intervention spillover effects on secondborn siblings and examine birth order differences in infant sleep.

METHODS

Secondborns (n = 117) of INSIGHT mothers were enrolled in an observational cohort, SIBSIGHT. The Brief Infant Sleep Questionnaire was collected at 3, 16, and 52 weeks. Generalized linear mixed models assessed differences among secondborns by firstborn randomization, as well as birth order differences at 16 and 52 weeks.

RESULTS

The RP group secondborns slept 42 minutes longer at night (95% confidence interval [95% CI]: 19-64) and 53 minutes longer total (95% CI: 17-90) than control secondborns. RP secondborns were more likely to self-soothe to sleep (odds ratio [OR] = 2.0, 95% CI: 1.1-3.7) and less likely to be fed back to sleep after waking (OR = 0.5, 95% CI: 0.3-0.9) than secondborns of control mothers. RP secondborns were more likely to have a bedtime ≤8 pm at 3 (OR = 2.9, 95% CI: 1.1-7.7) and 16 weeks (OR = 4.7, 95% CI: 2.0-11.0). Few differences in sleep parenting practices were observed when comparing siblings within families. Secondborns slept 37 minutes longer than firstborns at 16 weeks (CI: 7-67, P = .03).

CONCLUSIONS

The INSIGHT RP intervention for first-time mothers had a spillover effect to secondborns, positively impacting sleep duration and behaviors. Intervening with first-time mothers benefits both firstborns and subsequent children.

Metabolomic profiling of stool of two-year old children from the INSIGHT study reveals links between butyrate and child weight outcomes

BACKGROUND

Metabolomic analysis is commonly used to understand the biological underpinning of diseases such as obesity. However, our knowledge of gut metabolites related to weight outcomes in young children is currently limited.

OBJECTIVES

To (1) explore the relationships between metabolites and child weight outcomes, (2) determine the potential effect of covariates (e.g., child's diet, maternal health/habits during pregnancy, etc.) in the relationship between metabolites and child weight outcomes, and (3) explore the relationship between selected gut metabolites and gut microbiota abundance.

METHODS

Using ¹ H-NMR, we quantified 30 metabolites from stool samples of 170 two-year-old children. To identify metabolites and covariates associated with children's weight outcomes (BMI [weight/height² ], BMI z-score [BMI adjusted for age and sex], and growth index [weight/height]), we analysed the ¹ H-NMR data, along with 20 covariates recorded on children and mothers, using LASSO and best subset selection regression techniques. Previously characterized microbiota community information from the same stool samples was used to determine associations between selected gut metabolites and gut microbiota.

RESULTS

At age 2 years, stool butyrate concentration had a significant positive association with child BMI (p-value = 3.58 × 10^-4 ), BMI z-score (p-value = 3.47 × 10^-4 ), and growth index (p-value = 7.73 × 10^-4 ). Covariates such as maternal smoking during pregnancy are important to consider. Butyrate concentration was positively associated with the abundance of the bacterial genus Faecalibacterium (p-value = 9.61 × 10^-3 ).

CONCLUSIONS

Stool butyrate concentration is positively associated with increased child weight outcomes and should be investigated further as a factor affecting childhood obesity.