Understanding rapid infant weight gain prevention: a systematic review of quantitative and qualitative evidence

Rapid infant weight gain or point-in-time weight status: Which is the best predictor of later obesity and body composition?

OBJECTIVE

The aim of this study was to determine which growth indicator (weight, weight-for-length, BMI) and time frame (6- or 12-month intervals between 0 and 24 months) of rapid infant weight gain (RIWG) best predicted obesity risk and body composition at 11 years of age.

METHODS

RIWG (increase ≥0.67 z scores between two time points) was calculated from weight and length/height at birth, 0.5, 1, 1.5, and 2 years. The predictive value of each measure and time frame was calculated in relation to obesity (BMI ≥95th percentile) and body fat (fat mass index [FMI], dual-energy X-ray absorptiometry scan) at 11 years.

RESULTS

The sensitivity (1.5% to 62.1%) and positive predictive value (12.5% to 33.3%) of RIWG to predict obesity varied considerably. Having obesity at any time point appeared a stronger risk factor than any indicator of RIWG for obesity at 11 years. Obesity at any age during infancy consistently predicted a greater FMI of around 1.1 to 1.5 kg/m2 at 11 years, whereas differences for RIWG were inconsistent.

CONCLUSIONS

A simple measure of obesity status at a single time point between 6 and 24 months of age appeared a stronger risk factor for later obesity and FMI than RIWG assessed by any indicator, over any time frame.

Prenatal oxidative stress and rapid infant weight gain

BACKGROUND AND OBJECTIVES

Infant weight patterns predict subsequent weight outcomes. Rapid infant weight gain, defined as a >0.67 increase in weight-for-age z-score (WAZ) between two time points in infancy, increases obesity risk. Higher oxidative stress, an imbalance between antioxidants and reactive oxygen species, has been associated with low birthweight and paradoxically also with later obesity. We hypothesized that prenatal oxidative stress may also be associated with rapid infant weight gain, an early weight pattern associated with future obesity.

METHODS

Within the NYU Children's Health and Environment Study prospective pregnancy cohort, we analyzed associations between prenatal lipid, protein, and DNA urinary oxidative stress biomarkers and infant weight data. Primary outcome was rapid infant weight gain (>0.67 increase in WAZ) between birth and later infancy at the 8 or 12 month visit. Secondary outcomes included: very rapid weight gain (>1.34 increase in WAZ), low (<2500 g) or high (≥4000 g) birthweight, and low (< -1 WAZ) or high (>1 WAZ) 12 month weight.

RESULTS

Pregnant participants consented to the postnatal study (n = 541); 425 participants had weight data both at birth and in later infancy. In an adjusted binary model, prenatal 8-iso-PGF2α, a lipid oxidative stress biomarker, was associated with rapid infant weight gain (aOR 1.44; 95% CI: 1.16, 1.78, p = 0.001). In a multinomial model using ≤0.67 change in WAZ as a reference group, 8-iso-PGF2α was associated with rapid infant weight gain (defined as >0.67 but ≤1.34 WAZ; aOR 1.57, 95% CI: 1.19, 2.05, p = 0.001) and very rapid infant weight gain (defined as >1.34 WAZ; aOR 1.33; 95% CI: 1.02, 1.72, p < 0.05) Secondary analyses detected associations between 8-iso-PGF2α and low birthweight outcomes.

CONCLUSIONS

We found an association between 8-iso-PGF2α, a lipid prenatal oxidative stress biomarker, and rapid infant weight gain, expanding our understanding of the developmental origins of obesity and cardiometabolic disease.

Association of Maternal BMI and Rapid Infant Weight Gain With Childhood Body Size and Composition

OBJECTIVES

Maternal prepregnancy BMI (ppBMI) and an infant's rapid weight gain (RWG) are each associated with increased risk for childhood obesity. We hypothesized that ppBMI and RWG interact to further raise childhood obesity risk.

METHODS

Mother-infant dyads (n = 414) from the Healthy Start Study, an observational prebirth cohort, were included. RWG was defined as a weight-for-age z score increase of ≥0.67 from birth to 3 to 7 months. Body composition was measured by air displacement plethysmography at age 4 to 7 years. General linear regression models were fit to characterize associations between ppBMI, RWG, and their interaction with the outcomes of childhood BMI-for-age z score and percent fat mass (%FM).

RESULTS

A total of 18.6% (n = 77) of offspring experienced RWG. Maternal ppBMI and RWG were both positively associated with offspring BMI z score and %FM. RWG amplified the association between ppBMI and BMI z score, especially among females. Females exposed to maternal obesity and RWG had an average BMI at the 94th percentile (1.50 increase in childhood BMI z score) compared with those exposed to normal ppBMI and no RWG (average childhood BMI at the 51st percentile). RWG had a weaker effect on the association between ppBMI and %FM. Adjustment for breastfeeding status or childhood daily caloric intake did not significantly alter findings.

CONCLUSIONS

Rapid infant weight gain interacts with maternal ppBMI to jointly exacerbate risk of childhood obesity. Pediatric providers should monitor infants for RWG, especially in the context of maternal obesity, to reduce future risk of obesity.

The care of infants with rapid weight gain: Should we be doing more?

Rapid weight gain (RWG) during infancy is a known risk factor for later childhood obesity. It can be measured using a range of definitions across various time periods in the first 2 years of life. In recent years, some early childhood obesity prevention trials have included a focus on preventing RWG during infancy, with modest success. Overall, RWG during infancy remains common, yet little work has examined whether infants with this growth pattern should receive additional care when it is identified in health-care settings. In this viewpoint, we contend that RWG during infancy should be routinely screened for in health-care settings, and when identified, viewed as an opportunity for health-care professionals to instigate non-stigmatising discussions with families about RWG and general healthy practices for their infants. If families wish to engage, we suggest that six topics from early life obesity prevention studies (breastfeeding, formula feeding, complementary feeding, sleep, responsive parenting, and education around growth charts and monitoring) could form the foundations of conversations to help them establish and maintain healthy habits to support their infant's health and well-being and potentially lower the risk of later obesity. However, further work is needed to develop definitive guidelines in this area, and to address other gaps in the literature, such as the current lack of a standardised definition for RWG during infancy and a clear understanding of the time points over which it should be measured.

Effects of the Sleep SAAF responsive parenting intervention on rapid infant weight gain: A randomized clinical trial of African American families

Responsive parenting (RP) interventions reduce rapid infant weight gain but their effect for underserved populations is largely unknown. The Sleep SAAF (Strong African American Families) study is a two-arm randomized clinical trial for primiparous African American mother-infant dyads that compares an RP intervention to a child safety control over the first 16 weeks postpartum. Here we report on intervention effects on rapid infant weight gain and study implementation. Families were recruited from a mother/baby nursery shortly after delivery. Community Research Associates (CRAs) conducted intervention home visits at 3 and 8 weeks postpartum, and data collection home visits at 1, 8, and 16 weeks postpartum. To examine rapid infant weight gain, conditional weight gain (CWG) from 3 to 16 weeks, the primary outcome, and upward crossing of 2 major weight-for-age percentile lines were calculated. Among the 212 mother-infant dyads randomized, 194 completed the trial (92% retention). Randomized mothers averaged 22.7 years, 10% were married, and 49% participated in the Supplemental Nutrition Assistance Program (SNAP). Adjusting for covariates, mean CWG was lower among RP infants (0.04, 95% CI [-0.33, 0.40]) than among control infants (0.28, 95% CI [-0.08, 0.64]), reflecting non-significantly slower weight gain (p = 0.15, effect size d = 0.24). RP infants were nearly half as likely to experience upward crossing of 2 major weight-for-age percentile lines (14.1%) compared to control infants (24.2%), p = 0.09, odds ratio = 0.52 (95% CI [0.24, 1.12]). Implementation data revealed that participating families were engaged in the intervention visits and intervention facilitators demonstrated high fidelity to intervention materials. Findings show that RP interventions can be successfully implemented among African American families while suggesting the need for modifications to yield stronger effects on infant weight outcomes.

Infant appetite and weight gain in early infancy: Moderating effects of controlling feeding styles

Excessive infant weight gain is a strong predictor of later obesity. While controlling feeding has been linked to negative weight outcomes, research has not considered associations between infant appetite and maternal feeding simultaneously in relation to infant weight. This longitudinal study examined infant food responsiveness and slowness in eating as predictors of infant weight outcomes and tested controlling feeding styles (restrictive and pressuring) as moderators. Data came from a diverse sample of mothers and their infants participating in an ongoing longitudinal study. Mothers (n = 159) reported infant appetite and feeding styles at 2 postnatal timepoints (2-month visits and 6-month visits). The infant weight outcomes included change in weight-for-age z-scores (WAZ-change) and rapid weight gain (RIWG; WAZ-change ≥ 0.67 SD) from birth to the second postnatal visit. Data were analyzed using hierarchical multiple and logistic regressions, controlling for birthweight, gestational age, maternal race/ethnicity, feeding mode, and residing with an intimate partner. Over 25% of infants exhibited RIWG. Greater infant food responsiveness predicted both greater infant weight gain and RIWG status. Infant food responsiveness and slowness in eating interacted with controlling feeding styles in a unique way. Infants with higher food responsiveness whose mothers were less restrictive had greater weight gain (b = 0.61, p < 0.001) and increased probability of RIWG (b = 2.71, p < 0.01) than infants with more restrictive mothers. Higher slowness in eating was associated with a lower RIWG probability among infants of mothers with lower pressuring feeding (b = -1.86, p < 0.05). For infants with a large appetite, some level of restrictive feeding may be beneficial for preventing excessive weight gain while pressuring may exacerbate the positive association between faster eating and RIWG.

Early Life Factors Associated with Lean Body Mass in Spanish Children: CALINA Study

Early life is critical for the programming of body composition. The literature links perinatal factors with fat mass development and its future effects (e.g., obesity); however, little evidence exists between early life factors and lean body mass (LBM). This study follows up on a cohort of 416 Spanish children at ages six to eight, previously evaluated at birth in the CALINA study. Here, we studied the association between early life factors, LBM, and limb strength. Parental origin/nutritional status, maternal smoking during pregnancy, gestational diabetes/weight gain/age, birth weight (BW), early feeding, and rapid weight gain (RWG) were collected from primary care records. Bioimpedance analysis, dual-energy X-ray absorptiometry, peripheral quantitative computed tomography, and a handgrip/standing long jump test were used to assess fat-free mass index (FFMI), total lean soft tissue mass index (TLSTMI), muscle cross-sectional area index (MCSAI), and limb strength, respectively. In girls, maternal smoking, gestational age, and BW were positively associated with FFM/LSTM. In boys, the parents’ BMI, BW, and RWG were positively associated with FFM/LSTM. BW was associated with handgrip strength in both. Maternal BMI in girls and RWG in boys were negatively associated with the standing long jump. Early life programming plays a key role in determining LBM in children.

Addressing obesity in the first 1000 days in high risk infants: Systematic review

Early intervention is critical for addressing the challenge of childhood obesity. Yet many preventive interventions do not target infants most at risk of future overweight or obesity. This systematic review examines interventions delivered before 2 years that aim to ameliorate excess weight gain among infants at high risk of overweight or obesity, due to sociodemographic characteristics, parental weight or health status, infant feeding or health behaviours. We searched six databases for interventions: (a) delivered before age two, (b) specifically aimed at infants at high risk of childhood obesity and (c) that reported outcomes by weight status beyond 28 days. The search identified over 27,000 titles, and 49 papers from 38 studies met inclusion criteria: 10 antenatal interventions, 16 postnatal and 12 conducted both before and after birth. Nearly all targeted infant and/or maternal nutrition. Studies varied widely in design, obesity risk factors, outcomes and quality. Overall, nine interventions of varying quality reported some evidence of significantly improved child weight trajectory, although effects tended to diminish over time. Interventions that improved weight outcomes tended to engage parents for a longer period, and most offered health professional input and support. Two studies of limited quality reported significantly worse weight outcomes in the intervention group.

Pediatrician's Beliefs and Practices Around Rapid Infant Weight Gain: A Qualitative Study

Rapid infant weight gain is a risk factor for later obesity. The objective of this study was to examine primary care pediatricians’ beliefs and practices around rapid infant weight gain. Primary care pediatricians (N = 16) participated in a semi-structured interview about infant growth. Interviews were transcribed, analyzed for themes using the grounded theory and the constant comparative method then reliably coded for the presence of each theme. Three themes were identified, pediatricians (1) are uncertain about the concept, definition, and implications of excessive or rapid infant weight gain (N = 16, 100%), (2) are more comfortable with management of inadequate versus excessive or rapid weight gain (N = 10, 62.5%), and (3) perceive the primary cause of excessive or rapid infant weight gain to be overfeeding (N = 10, 62.5%). In conclusion, pediatricians are uncertain about the concept, definition, management, and long-term risks of rapid infant weight gain. Interventions to increase awareness and pediatrician sense of competence in management of rapid infant weight gain are needed.