Modifiable early-life risk factors for childhood adiposity and overweight: an analysis of their combined impact and potential for prevention.

BACKGROUND: Early life may be a "critical period" when appetite and regulation of energy balance are programmed, with lifelong consequences for obesity risk. Insight into the potential impact of modifying early-life risk factors on later obesity can be gained by evaluating their combined effects. OBJECTIVE: The objective was to examine the relation between the number of early-life risk factors and obesity outcomes among children in a prospective birth cohort (Southampton Women's Survey). DESIGN: Five risk factors were defined: maternal obesity [prepregnant body mass index (BMI; in kg/m(2)) >30], excess gestational weight gain (Institute of Medicine, 2009), smoking during pregnancy, low maternal vitamin D status (<64 nmol/L), and short duration of breastfeeding (none or <1 mo). Obesity outcomes examined when the children were aged 4 and 6 y were BMI, dual-energy X-ray absorptiometry-assessed fat mass, overweight, or obesity (International Obesity Task Force). Data were available for 991 mother-child pairs, with children born between 1998 and 2003. RESULTS: Of the children, 148 (15%) had no early-life risk factors, 330 (33%) had 1, 296 (30%) had 2, 160 (16%) had 3, and 57 (6%) had 4 or 5. At both 4 and 6 y, there were positive graded associations between number of early-life risk factors and each obesity outcome (all P < 0.001). After taking account of confounders, the relative risk of being overweight or obese for children who had 4 or 5 risk factors was 3.99 (95% CI: 1.83, 8.67) at 4 y and 4.65 (95% CI: 2.29, 9.43) at 6 y compared with children who had none (both P < 0.001). CONCLUSIONS: Having a greater number of early-life risk factors was associated with large differences in adiposity and risk of overweight and obesity in later childhood. These findings suggest that early intervention to change these modifiable risk factors could make a significant contribution to the prevention of childhood obesity.

Association of early childhood abdominal circumference and weight gain with blood pressure at 36†months of age: secondary analysis of data from a prospective cohort study.

OBJECTIVES: To assess whether changes in measures of fat distribution and body size during early life are associated with blood pressure at 36 months of age. DESIGN: Analysis of data collected from a prospective cohort study. SETTING: Community-based investigation in Southampton, UK. PARTICIPANTS: 761 children with valid blood pressure measurements, born to women participating in the Southampton Women's Survey. PRIMARY AND SECONDARY OUTCOME MEASURES: Anthropometric measurements were collected at 0, 6, 12, 24 and 36 months and conditional changes between the time points calculated. Blood pressure was measured at 36 months. Factors possibly influencing the blood pressure were assessed using linear regression. All independent variables of interest and confounding variables were included in stepwise multiple regression to identify the model that best predicted blood pressure at 36 months. RESULTS: Greater conditional gains in abdominal circumference (AC) between 0-6 and 24-36 months were associated with higher systolic and diastolic blood pressures at 36 months (p<0.001). Subscapular skinfold and height gains were weakly associated with higher blood pressures, while greater weight gains between 0-6, 12-24 and 24-36 months were more strongly associated, but the dominant influences were AC gains, particularly from 0-6 to 24-36 months. Thus one SD score increases in AC between 0-6 and 24-36 months were associated with 1.59 mm Hg (95% CI 0.97 to 2.21) and 1.84 mm Hg (1.24 to 2.46) higher systolic blood pressures, respectively, and 1.04 mm Hg (0.57 to 1.51) and 1.02 mm Hg (0.56, 1.48) higher diastolic pressures, respectively. CONCLUSIONS: Conditional gains in abdominal circumference, particularly within 6 months of birth and in the year preceding measurement, were more positively associated with blood pressure at 36 months than gains in other anthropometric measures. Above-average AC gains in early childhood may contribute to adult hypertension and increased cardiovascular disease risk.

The effect of early confirmation of hearing loss on the behaviour in middle childhood of children with bilateral hearing impairment.

AIM: To determine if the benefit of early confirmation of permanent childhood hearing impairment (PCHI) on children's receptive language development is associated with fewer behavioural problems. METHOD: Follow-up of a total population cohort of 120 children with PCHI of moderate or greater severity (≥ 40 decibels relative to hearing threshold level) (67 males, 53 females; mean age 7 y 11 mo, range 5 y 5 mo-11 y 8 mo) and 63 hearing children (37 males, 26 females; mean age 8 y 1 mo, range 6 y 4 mo-9 y 10 mo). The main outcome measures were the Strengths and Difficulties Questionnaire (SDQ) completed by teachers and parents and the Vineland Adaptive Behaviour Scales (VABS) which are completed on the basis of a parental interview. RESULTS: Children with PCHI had lower standard scores than hearing children on the Daily Living Skills (p=0.001) and the Socialisation (p=0.001) scales of the VABS. They had significantly higher Total Behaviour Problem scores on the parent-rated (p=0.002) and teacher-rated SDQ (p=0.03). Children for whom PCHI was confirmed by 9 months did not have significantly fewer problems on the behavioural measures than those confirmed after that age (p=0.635 and p=0.196). INTERPRETATION: Early confirmation has a beneficial effect on receptive language development but no significant impact in reducing behavioural problems in children with PCHI.

Breastfeeding, the use of docosahexaenoic acid-fortified formulas in infancy and neuropsychological function in childhood.

OBJECTIVE: To investigate the relation between breastfeeding, use of docosahexaenoic acid (DHA)-fortified formula and neuropsychological function in children. DESIGN: Prospective cohort study. SETTING: Southampton, UK. SUBJECTS: 241 children aged 4 years followed up from birth. MAIN OUTCOME MEASURES: IQ measured by the Wechsler Pre-School and Primary Scale of Intelligence (3rd edn), visual attention, visuomotor precision, sentence repetition and verbal fluency measured by the NEPSY, and visual form-constancy measured by the Test of Visual-Perceptual Skills (Non-Motor). RESULTS: In unadjusted analyses, children for whom breast milk or DHA-fortified formula was the main method of feeding throughout the first 6 months of life had higher mean full-scale and verbal IQ scores at age 4 years than those fed mainly unfortified formula. After adjustment for potential confounding factors, particularly maternal IQ and educational attainment, the differences in IQ between children in the breast milk and unfortified formula groups were severely attenuated, but children who were fed DHA-fortified formula had full-scale and verbal IQ scores that were respectively 5.62 (0.98 to 10.2) and 7.02 (1.56 to 12.4) points higher than children fed unfortified formula. However, estimated total intake of DHA in milk up to age 6 months was not associated with subsequent IQ or with score on any other test. CONCLUSIONS: Differences in children's intelligence according to type of milk fed in infancy may be due more to confounding by maternal or family characteristics than to the amount of long-chain polyunsaturated fatty acids they receive in milk.

Variations in infant feeding practice are associated with body composition in childhood: a prospective cohort study.

CONTEXT: Most studies of infant diet and later body composition focus on milk feeding; few consider the influence of variations in the weaning diet. OBJECTIVE: Our objective was to examine how variations in milk feeding and the weaning diet relate to body composition at 4 yr. STUDY POPULATION: A total of 536 children participating in a prospective birth cohort study. DESIGN: Diet was assessed at 6 and 12 months of age. Compliance with weaning guidance was defined by the infant's score for a principal component analysis-defined dietary pattern (infant guidelines) at 12 months. Infants with high infant guidelines scores had diets characterized by high consumption of fruit, vegetables, and home-prepared foods. Body composition was assessed at 4 yr by dual x-ray absorptiometry. RESULTS: Longer duration of breastfeeding was associated with lower fat mass at 4 yr [4.5 kg, 95% confidence interval (CI) of 4.3-4.7 kg, in children breastfed for 12 months or more, compared with 5.0 (95% CI 4.7-5.3) kg in children never breastfed (P = 0.002)] but was not related to body mass index. Children with high infant guidelines scores had a higher lean mass [12.6 (95% CI 12.3-12.9) kg in children in the top quarter of the distribution, compared with 12.0 (95% CI 11.7-12.4) kg in children in the bottom quarter (P = 0.001)]. These associations were independent and were little changed by adjustment for confounding factors. CONCLUSIONS: These data suggest that variations in both milk feeding and in the weaning diet are linked to differences in growth and development, and they have independent influences on body composition in early childhood.

Dietary patterns in infancy and cognitive and neuropsychological function in childhood.

BACKGROUND: Trials in developing countries suggest that improving young children's diet may benefit cognitive development. Whether dietary composition influences young children's cognition in developed countries is unclear. Although many studies have examined the relation between type of milk received in infancy and subsequent cognition, there has been no investigation of the possible effect of variations in the weaning diet. METHODS: We studied 241 children aged 4 years, whose diet had been assessed at age 6 and 12 months. We measured IQ with the Wechsler Pre-School and Primary Scale of Intelligence, visual attention, visuomotor precision, sentence repetition and verbal fluency with the Developmental Neuropsychological Assessment (NEPSY), and visual form-constancy with the Test of Visual Perceptual Skills. RESULTS: In sex-adjusted analyses, children whose diet in infancy was characterised by high consumption of fruit, vegetables and home-prepared foods ('infant guidelines' dietary pattern) had higher full-scale and verbal IQ and better memory performance at age 4 years. Further adjustment for maternal education, intelligence, social class, quality of the home environment and other potential confounding factors attenuated these associations but the relations between higher 'infant guidelines' diet score and full-scale and verbal IQ remained significant. For a standard deviation increase in 'infant guidelines' diet score at 6 or 12 months full-scale IQ rose by .18 (95% CI .04 to .31) of a standard deviation. For a standard deviation increase in 'infant guidelines' diet score at 6 months verbal IQ rose by .14 (.01 to .27) of a standard deviation. There were no associations between dietary patterns in infancy and 4-year performance on the other tests. CONCLUSIONS: These findings suggest that dietary patterns in early life may have some effect on cognitive development. It is also possible that they reflect the influence of unmeasured confounding factors.

What do babies eat? Evaluation of a food frequency questionnaire to assess the diets of infants aged 12 months.

OBJECTIVE: To evaluate the relative validity of an FFQ for assessing nutrient intakes in 12-month-old infants. DESIGN AND SETTING: The FFQ was developed to assess the diets of infants born to women in the Southampton Women's Survey (SWS), a population-based survey of young women and their offspring. The energy and nutrient intakes obtained from an interviewer-administered FFQ were compared with those obtained from 4 d weighed diaries (WD). SUBJECTS AND METHODS: A sub-sample of fifty infants (aged 1 year) from the SWS had their diets assessed by both methods. The FFQ recorded the frequencies and amounts of foods and drinks consumed by the infants over the previous 28 d; milk consumption was recorded separately. The WD recorded the weights of all foods and drinks consumed by the infants on 4 d following the FFQ completion. RESULTS: The Spearman rank correlation coefficients for intakes of energy, macronutrients and eighteen micronutrients, determined by the two methods, ranged from r = 0.25 to 0.66. Bland-Altman statistics showed that mean differences between methods were in the range +5% to +60% except for vitamin D (+106%). Differences in micronutrient intake were partly explained by changes in patterns of milk consumption between the two assessments. CONCLUSION: Although there were differences in absolute energy and nutrient intakes between methods, there was reasonable agreement in the ranking of intakes. The FFQ is a useful tool for assessing energy and nutrient intakes of healthy infants aged around 12 months.

Oily fish intake during pregnancy--association with lower hyperactivity but not with higher full-scale IQ in offspring.

BACKGROUND: Long-chain omega-3 polyunsaturated fatty acids are thought to be important for fetal neurodevelopment. Animal studies suggest that a deficiency of omega-3 fatty acids may lead to behavioural or cognitive deficits. As oily fish is a major dietary source of omega-3 fatty acids, it is possible that low intake of fish during pregnancy may have adverse effects on the developing fetal brain. METHODS: We used the Strengths and Difficulties Questionnaire and the Wechsler Abbreviated Scale of Intelligence to assess behavioural problems and intelligence in 217 nine-year-old children. The mothers of these children had participated in a study of nutrition during pregnancy during which fish intake was assessed in early and late gestation. RESULTS: Children whose mothers had eaten oily fish in early pregnancy had a reduced risk of hyperactivity compared to those whose mothers did not eat oily fish: OR .34, 95% CI .15 to .78, after adjustment for potential confounding factors. Children whose mothers had eaten fish (whether oily or non-oily) in late pregnancy had a verbal IQ that was 7.55 points higher (95% CI .75 to 14.4) than those whose mothers did not eat fish. There were, however, no significant associations between fish intake in pregnancy and other behavioural problems or full-scale and performance intelligence, after adjustment for potential confounding factors. CONCLUSIONS: Although maternal fish intake in pregnancy was associated with hyperactivity scores and verbal IQ in children, in general, how much fish women ate during pregnancy appeared to have little long-term relation with neurodevelopmental outcomes in their child.

Health status and health-related quality of life preference-based outcomes of children who are aged 7 to 9 years and have bilateral permanent childhood hearing impairment.

OBJECTIVE: The objective of this study was to describe the health status and health-related quality of life preference-based outcomes of children with diagnosed bilateral permanent childhood hearing impairment and a comparison group of English-speaking children with normal hearing. METHODS: We studied 120 children who were aged 7 to 9 years and had bilateral permanent childhood hearing impairment of moderate or greater severity, identified from a cohort of 156,733 children who were born in 8 districts of southern England, and 63 English-speaking children with normal hearing and the same place of birth and age at assessment. Principal caregivers were interviewed by using the Health Utilities Index Mark III questionnaire for proxy-assessed usual health status assessment. Levels of function within each of the 8 attributes of the Health Utilities Index Mark III (cognition, vision, hearing, speech, ambulation, dexterity, emotion, and pain) were recorded. RESULTS: Bilateral permanent childhood hearing impairment is associated with significantly increased proportions of suboptimal levels of function and significantly lower single-attribute utility scores in 6 of the 8 attributes of the Health Utilities Index Mark III: vision, hearing, speech, ambulation, dexterity, and cognition. Compared with the children with normal hearing, the mean multiattribute utility score for the children with hearing impairment was significantly lower for both the whole group and the moderate, severe, and profound severity subgroups. The differences in the distributions of the multiattribute utility scores between the children with hearing impairment as a group and the children with normal hearing and between each of the severity subgroups and the children with normal hearing all were statistically significant. CONCLUSIONS: This study provides rigorous evidence of an association between bilateral permanent childhood hearing impairment and diminished health status and health-related quality of life preference-based outcomes during midchildhood.

Maternal size in pregnancy and body composition in children.

CONTEXT: Evidence suggests that babies' fat mass at birth is greater if their mothers were themselves fatter during pregnancy, but it is unclear whether this association persists into childhood. OBJECTIVE: Our objective was to examine the relation between maternal size in pregnancy, early growth and body composition in children. DESIGN AND SETTING: We conducted a prospective cohort study in Southampton, United Kingdom. PARTICIPANTS: Participants included 216 9-yr-old children whose mothers had participated in a study of nutrition during pregnancy. MAIN OUTCOME MEASURES: Fat mass and lean mass were measured by dual-energy x-ray absorptiometry and adjusted for height (fat mass index and lean mass index). RESULTS: Fat mass index at age 9 yr was greater in children whose mothers had a larger mid-upper arm circumference in late pregnancy or a higher prepregnant body mass index. For 1 sd increase in maternal mid-upper arm circumference in late pregnancy, fat mass index rose by 0.26 [95% confidence interval (CI) 0.06-0.46] sd in boys and by 0.44 (95% CI 0.31-0.57) sd in girls. For 1 sd increase in maternal prepregnant BMI, fat mass index rose by 0.26 (95% CI 0.04-0.48) sd in boys and by 0.42 (95% CI 0.29-0.56) sd in girls. CONCLUSIONS: Mothers with a higher prepregnant body mass index or a larger mid-upper arm circumference during pregnancy tend to have children with greater adiposity at age 9. The extent to which this is attributable to genetic factors, the influence of maternal lifestyle on that of her child, or maternal adiposity acting specifically during pregnancy on the child's fat mass cannot be determined in this study.

Language ability after early detection of permanent childhood hearing impairment.

BACKGROUND: Children with bilateral permanent hearing impairment often have impaired language and speech abilities. However, the effects of universal newborn screening for permanent bilateral childhood hearing impairment and the effects of confirmation of hearing impairment by nine months of age on subsequent verbal abilities are uncertain. METHODS: We studied 120 children with bilateral permanent hearing impairment identified from a large birth cohort in southern England, at a mean of 7.9 years of age. Of the 120 children, 61 were born during periods with universal newborn screening and 57 had hearing impairment that was confirmed by nine months of age. The primary outcomes were language as compared with nonverbal ability and speech expressed as z scores (the number of standard deviations by which the score differed from the mean score among 63 age-matched children with normal hearing), adjusted for the severity of the hearing impairment and for maternal education. RESULTS: Confirmation of hearing impairment by nine months of age was associated with higher adjusted mean z scores for language as compared with nonverbal ability (adjusted mean difference for receptive language, 0.82; 95 percent confidence interval, 0.31 to 1.33; and adjusted mean difference for expressive language, 0.70; 95 percent confidence interval, 0.13 to 1.26). Birth during periods with universal newborn screening was also associated with higher adjusted z scores for receptive language as compared with nonverbal ability (adjusted mean difference, 0.60; 95 percent confidence interval, 0.07 to 1.13), although the z scores for expressive language as compared with nonverbal ability were not significantly higher. Speech scores did not differ significantly between those who were exposed to newborn screening or early confirmation and those who were not. CONCLUSIONS: Early detection of childhood hearing impairment was associated with higher scores for language but not for speech in midchildhood.

Maternal diet during pregnancy and carotid intima-media thickness in children.

OBJECTIVE: Autopsy studies show that intimal lipid accumulations in arteries are often present at birth, suggesting that the prenatal environment plays a role in the pathogenesis of atherosclerosis. In animal models, a restricted or unbalanced maternal diet during gestation can influence susceptibility to atherosclerosis, but the relation in humans between maternal diet during pregnancy and atherogenesis is unknown. METHODS AND RESULTS: We measured carotid intima-media thickness (IMT) in 216 nine-year-old children whose mothers had participated in a study of nutrition during pregnancy. IMT was greater in boys, in children who were heavier, in those with higher systolic blood pressure, and in those who took less exercise. Increased IMT was associated with a lower maternal energy intake in early (P=0.029) or late (P=0.006) pregnancy, after adjustment for these factors. Mean IMT of children whose mothers were in the lowest quarter of the distribution of energy intake in late pregnancy was 0.027 mm (95% confidence interval, 0.004 to 0.049) greater than that of those whose mothers were in the highest quarter of the distribution. CONCLUSIONS: Lower maternal energy intake during pregnancy may increase the susceptibility to atherogenesis of the child.

Critical periods of brain growth and cognitive function in children.

There is evidence that IQ tends to be higher in those who were heavier at birth or who grew taller in childhood and adolescence. Although these findings imply that growth in both foetal and postnatal life influences cognitive performance, little is known about the relative importance of brain growth during different periods of development. We investigated the relationship between brain growth in different periods of pre- and postnatal life and cognitive function in 221 9-year-old children whose mothers had taken part in a study of nutrition in pregnancy and whose head circumference had been measured at 18 weeks gestation, birth and 9 months of age. Cognitive function of the children and their mothers was assessed with the Wechsler Abbreviated Scale of Intelligence. Full-scale IQ at age 9 years rose by 1.98 points [95% confidence interval (CI) 0.34 to 3.62] for each SD increase in head circumference at 9 months and by 2.87 points (95% CI 1.05 to 4.69) for each SD increase in head circumference at 9 years of age, after adjustment for sex, number of older siblings, maternal IQ, age, education, social class, duration of breastfeeding and history of low mood in the post-partum period. Postnatal head growth was significantly greater in children whose mothers were educated to degree level or of higher socio-economic status. There was no relation between IQ and measurements of head size at 18 weeks gestation or at birth. These results suggest that brain growth during infancy and early childhood is more important than growth during foetal life in determining cognitive function.