ObjectiveTo determine risk factors for childhood overweight that can be identified during the first year of life to facilitate early identification and targeted intervention.DesignSystematic review and meta-analysis.Search strategyElectronic database search of MEDLINE, EMBASE, PubMed and CAB Abstracts.Eligibility criteriaProspective observational studies following up children from birth for at least 2 years.ResultsThirty prospective studies were identified. Significant and strong independent associations with childhood overweight were identified for maternal pre-pregnancy overweight, high infant birth weight and rapid weight gain during the first year of life. Meta-analysis comparing breastfed with non-breastfed infants found a 15% decrease (95% CI 0.74 to 0.99; I2=73.3%; n=10) in the odds of childhood overweight. For children of mothers smoking during pregnancy there was a 47% increase (95% CI 1.26 to 1.73; I2=47.5%; n=7) in the odds of childhood overweight. There was some evidence associating early introduction of solid foods and childhood overweight. There was conflicting evidence for duration of breastfeeding, socioeconomic status at birth, parity and maternal marital status at birth. No association with childhood overweight was found for maternal age or education at birth, maternal depression or infant ethnicity. There was inconclusive evidence for delivery type, gestational weight gain, maternal postpartum weight loss and ‘fussy’ infant temperament due to the limited number of studies.ConclusionsSeveral risk factors for both overweight and obesity in childhood are identifiable during infancy. Future research needs to focus on whether it is clinically feasible for healthcare professionals to identify infants at greatest risk.

The risk factors for childhood overweight and obesity are known and can be identified antenatally or during infancy, however, the majority of effective interventions are designed for older children. This review identified interventions designed to reduce the risk of overweight/obesity that were delivered antenatally or during the first 2 years of life, with outcomes reported from birth to 7 years of age. Six electronic databases were searched for papers reporting randomised controlled trials of interventions published from January 1990 to September 2013. A total of 35 eligible studies were identified, describing 27 unique trials of which 24 were behavioural and three were non‐behavioural. The 24 behavioural trials were categorised by type of intervention: (1) nutritional and/or responsive feeding interventions targeted at parents of infants, which improved feeding practices and had some impact on child weight (n = 12); (2) breastfeeding promotion and lactation support for mothers, which had a positive effect on breastfeeding but not child weight (n = 5); (3) parenting and family lifestyle (n = 4); and (4) maternal health (n = 3) interventions that had some impact on feeding practices but not child weight. The non‐behavioural trials comprised interventions manipulating formula milk composition (n = 3). Of these, lower/hydrolysed protein formula milk had a positive effect on weight outcomes. Interventions that aim to improve diet and parental responsiveness to infant cues showed most promise in terms of self‐reported behavioural change. Despite the known risk factors, there were very few intervention studies for pregnant women that continue during infancy which should be a priority for future research.

WHAT'S KNOWN ON THIS SUBJECT: Several risk factors for both overweight and obesity in childhood are identifiable during infancy. WHAT THIS STUDY ADDS:A simple risk algorithm can be used to quantify risk of overweight in children. It can be used to help identify at-risk infants in a clinical setting to facilitate targeted intervention.abstract OBJECTIVE: The aim of this study was to develop and validate a risk score algorithm for childhood overweight based on a prediction model in infants. METHODS:Analysis was conducted by using the UK Millennium Cohort Study. The cohort was divided randomly by using 80% of the sample for derivation of the risk algorithm and 20% of the sample for validation.Stepwise logistic regression determined a prediction model for childhood overweight at 3 years defined by the International Obesity Task Force criteria. Predictive metrics R 2 , area under the receiver operating curve (AUROC), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated.RESULTS: Seven predictors were found to be significantly associated with overweight at 3 years in a mutually adjusted predictor model: gender, birth weight, weight gain, maternal prepregnancy BMI, paternal BMI, maternal smoking in pregnancy, and breastfeeding status. Risk scores ranged from 0 to 59 corresponding to a predicted risk from 4.1% to 73.8%. The model revealed moderately good predictive ability in both the derivation cohort (R 2 = 0.92, AUROC = 0.721, sensitivity = 0.699, specificity = 0.679, PPV = 38%, NPV = 87%) and validation cohort (R 2 = 0.84, AUROC = 0.755, sensitivity = 0.769, specificity = 0.665, PPV = 37%, NPV = 89%).CONCLUSIONS: Using a prediction algorithm to identify at-risk infants could reduce levels of child overweight and obesity by enabling health professionals to target prevention more effectively. Further research needs to evaluate the clinical validity, feasibility, and acceptability of communicating this risk.

BackgroundA number of risk factors are associated with the development of childhood obesity which can be identified during infancy. These include infant feeding practices, parental response to infant temperament and parental perception of infant growth and appetite. Parental beliefs and understanding are crucial determinants of infant feeding behaviour; therefore any intervention would need to take account of their views. This study aimed to explore UK parents' beliefs concerning their infant's size, growth and feeding behaviour and parental receptiveness to early intervention aimed at reducing the risk of childhood obesity.MethodSix focus groups were undertaken in a range of different demographic localities, with parents of infants less than one year of age. The focus groups were audio-recorded, transcribed verbatim and thematic analysis applied using an interpretative, inductive approach.Results38 parents (n = 36 female, n = 2 male), age range 19-45 years (mean 30.1 years, SD 6.28) participated in the focus groups. 12/38 were overweight (BMI 25-29.99) and 8/38 obese (BMI >30). Five main themes were identified. These were a) parental concern about breast milk, infant contentment and growth; b) the belief that the main cause of infant distress is hunger is widespread and drives inappropriate feeding; c) rationalisation for infants' larger size; d) parental uncertainty about identifying and managing infants at risk of obesity and e) intentions and behaviour in relation to a healthy lifestyle.ConclusionsThere are a number of barriers to early intervention with parents of infants at risk of developing obesity. Parents are receptive to prevention prior to weaning and need better support with best practice in infant feeding. In particular, this should focus on helping them understand the physiology of breast feeding, how to differentiate between infant distress caused by hunger and other causes and the timing of weaning. Some parents also need guidance about how to recognize and prepare healthy foods and facilitate physical activity for their infants.