Early growth patterns and long-term obesity risk

PURPOSE OF REVIEW

This review is an update on recent findings regarding early growth patterns and later obesity. These data are important because the potential programming of obesity in early life provides hope for new prevention strategies targeting early growth for long-term benefits.

RECENT FINDINGS

Recent findings regarding the association of childhood or adulthood obesity with fetal growth, gestational weight gain, maternal diabetes, or infancy weight gain are reviewed. Some related outcomes and potential mechanisms are also described. Most studies remain observational and confirm previous findings, but some intervention studies have begun to appear in the recent literature and support some, but not other, observed associations.

SUMMARY

Past and recent findings confirm the association of early growth patterns with obesity. However, causality must be demonstrated and safety must be established before translating these findings into public health recommendations.

Relation of immediate postnatal growth with obesity and related metabolic risk factors in adulthood: the northern Finland birth cohort 1966 study

The authors examined associations between postnatal growth velocity through age 2 years and metabolic outcomes at age 31 years in a population-based birth-cohort study of 3,778 Finns (1966-1998). Approximately 8 height measurements and 9 weight measurements were obtained from birth to age 2 years. Peak height velocity (PHV) and peak weight velocity (PWV) in infancy were derived from parametric growth curves fitted to longitudinal height and weight growth data. Body mass index (BMI), waist circumference (WC), high density lipoprotein (HDL) cholesterol, triglycerides, glucose, systolic and diastolic blood pressure (BP), and the metabolic syndrome were measured at age 31 years. PHV was significantly positively associated with systolic and diastolic BP and WC in adulthood. For each 8-cm/year (2-standard-deviation) increase in PHV, WC increased by 1.60 cm (95% confidence interval: 0.73, 2.46), after adjustment for potential confounders, including birth weight. PWV was significantly associated with adulthood systolic BP, WC, and BMI. A 4-kg/year higher PWV was associated with a 1.87-cm (95% confidence interval: 1.08, 2.65) larger WC in adulthood, after adjustment for potential confounders. HDL cholesterol (direct), triglycerides (inverse), and metabolic syndrome (inverse) displayed associations with PWV only after BMI was accounted for. These results showed that growth during the immediate postnatal period is associated with adulthood obesity and BP. Lifestyle changes from early life might be important in reducing adulthood obesity and high-BP risk.

Mechanisms of endothelium-dependent vasodilation in male and female, young and aged offspring born growth restricted

Numerous epidemiological studies have shown that cardiovascular dysfunction in adult life may be programmed by compromised growth in utero. Aging is a risk factor for vascular endothelial-dependent dysfunction. After birth, the impact of intrauterine growth restriction (IUGR) on normal aging mechanisms of vascular dysfunction is not known. We hypothesized that IUGR would cause changes in vascular function that would affect the mechanisms of endothelium-dependent vasodilation later in life in an age- or sex-dependent manner. To create an IUGR model, pregnant Sprague-Dawley rats were placed in a hypoxic (12% O(2)) or control (room air, 21% O(2)) environment from days 15 to 21 of the pregnancy, and both male and female offspring were investigated at 4 or 12 mo of age. Endothelial function was assessed in small mesenteric arteries using methacholine (MCh)-induced vasodilation in a wire myograph system. The involvement of nitric oxide (NO), prostaglandins, and endothelium-derived hyperpolarizing factor (EDHF) was assessed using the inhibitors N(omega)-nitro-l-arginine methyl ester hydrochloride, meclofenamate, or a combination of apamin and TRAM-34 (SK(Ca) and IK(Ca) blockers), respectively. EDHF-induced vasodilation was further investigated by using inhibitors of P450 epoxygenases [N-methylsulfonyl-6-(2-propargyloxyphenyl) hexanamide] and gap junctions (18alpha-glycyrrhetinic acid). NO-mediated vasodilation was significantly reduced in aged controls and both young and aged IUGR females. EDHF-mediated vasodilation was maintained in all groups; however, an additional involvement of gap junctions was found in females exposed to hypoxia in utero, which may represent a compensatory mechanism. A change in the mechanisms of vasodilation occurring at an earlier age in IUGR offspring may predispose them to adult cardiovascular diseases.

Determinants of the relationship between cytokine production in pregnant women and their infants

Exposure to environmental factors during fetal life and infancy is thought to play an important role in the early development of innate and adaptive immunity. The immunological relationship between mother and infant and the effect that environmental exposures have during pregnancy and early childhood have not been studied extensively. Here the production of cytokines was measured in 146 pairs of mothers and their 2- month-old infants. The effect of place of residence, socio-economic variables, parasitic infections as well as maternal and child characteristics on measured cytokine production was determined. Mothers producing high levels of IL-10, IFN-gamma and IL-5 were more likely to have infants who also produced high levels of these cytokines either spontaneously (OR 2.6(95%CI 1.2-5.4), OR 2.9(CI 1.3-6.6), OR 11.2(CI 4.6-27.2), respectively) or in response to PHA (IL-10: OR 3.0(CI 1.4-6.6), IFN-gamma: OR 2.0(CI 1.0-4.2), respectively) even after adjustment for potential confounding variables. This was not the case for TNF-alpha. In response to LPS, place of residence was a strong determinant of infant IL-10 (OR 0.2(CI 0.1-0.9)) and TNF-alpha (OR 0.3(CI 0.1-0.9)) production. Maternal protozoan infections was independently associated with reduced infant IL10 in response to PHA and to LPS as well as reduced TNF-alpha and IFN-gamma in response to PHA. These results indicate strong relationship between maternal and infant's cellular immune responses even after taking into account many environmental influences that could affect infant's response directly or indirectly through uterine microenvironment. However, place of residence and intestinal infections may still directly affect the immune responses of the infant. Taken together, the study provides evidence for imprinted cytokine responses of an infant which may have implications for their reaction to incoming antigens, warranting further investigation into the role that genetics or epigenetics play in shaping the cytokine response by an infant to self or external antigens.

Fetal origins of insulin resistance and the metabolic syndrome: a key role for adipose tissue?

For several years now, the epidemiological data have shown an inverse relationship between birth-weight and the development in later life of cardiovascular disease and metabolic disorders. The term "small for gestational age" (SGA) describes a neonate whose birth-weight is two standard deviations (SD) below the reference mean, corrected for gestational age and gender. SGA is associated with increased risks of developing hypertension, insulin resistance and type2 diabetes. However, the association with an atherogenic lipid profile is less clear. Nevertheless, all of the components of the metabolic syndrome are present. Yet, in spite of the large body of data in the literature, the biological mechanisms underlying this association are still unclear. To explain the association, various hypotheses have been proposed, pointing to the role of a detrimental fetal environment or genetic susceptibility, or interaction between the two, and to the particular dynamic changes in adiposity that occur during catch-up growth. However, not only quantitative, but also qualitative, abnormalities of adipose tissue have been observed, suggesting a critical role of this organ in the development of metabolic complications.

Growth trajectories and intellectual abilities in young adulthood: The Helsinki Birth Cohort study

Slow childhood growth is associated with poorer intellectual ability. The critical periods of growth remain uncertain. Among 2,786 Finnish male military conscripts (1952-1972) born in 1934-1944, the authors tested how specific growth periods from birth to age 20 years predicted verbal, visuospatial, and arithmetic abilities at age 20. Small head circumference at birth predicted poorer verbal, visuospatial, and arithmetic abilities. The latter 2 measures were also associated with lower weight and body mass index (weight (kg)/height (m)(2)) at birth (for a 1-standard-deviation (SD) decrease in test score per SD decrease in body size > or = 0.05, P's < 0.04). Slow linear growth and weight gain between birth and age 6 months, between ages 6 months and 2 years, or both predicted poorer performance on all 3 tests (for a 1-SD decrease in test score per SD decrease in growth > or = 0.05, P's < 0.03). Reduced linear growth between ages 2 and 7 years predicted worse verbal ability, and between age 11 years and conscription it predicted worse performance on all 3 tests. Prenatal brain growth and linear growth up to 2 years after birth form a first critical period for intellectual development. There is a second critical period, specific for verbal development, between ages 2 and 7 years and a third critical period for all 3 tested outcomes during adolescence.

Fetal and postnatal growth and body composition at 6 months of age

OBJECTIVES

The objectives of the study was to examine which parental, fetal, and postnatal characteristics are associated with fat and lean mass at the age of 6 months and examine the effect of growth (catch-down, catch-up) in fetal life and early infancy on fat and lean mass.

DESIGN

This study was embedded in the Generation R Study, a prospective cohort study from early fetal life onward. Body composition was measured by dual-energy X-ray absorptiometry in 252 infants at 6 months. Parental, fetal, and postnatal data were collected by physical and fetal ultrasound examinations and questionnaires.

RESULTS

Children with fetal catch-up in weight (gain in weight sd score >0.67) in the second trimester tended to have a higher fat mass percentage [FM(%)] at 6 months of age, whereas children with fetal catch-down in weight had a lower FM(%) compared with nonchangers. In the third trimester, both catch-up and catch-down in weight were associated with an increase in FM(%) at 6 months. Children with catch-down in the third trimester had a greater risk for postnatal catch-up in weight greater than 0.67 sd score. Birth weight and weight at 6 wk were positively associated with fat mass at 6 months. Postnatal catch-up in weight within 6 wk after birth had the highest association with total and truncal FM(%) at 6 months. Total and truncal FM were higher in girls.

CONCLUSION

Catch-down in weight in the third trimester was strongly associated with postnatal catch-up within 6 wk after birth, and both were associated with an increase in fat mass at the age of 6 months. Our study shows that fetal as well as postnatal growth patterns are associated with body composition in early childhood.

Weight gain in childhood and blood lipids in adolescence

Aim:

To assess the effect of weight gain in childhood on blood lipid levels in adolescence.

Methods:

A population-based birth cohort carried out in Pelotas, Southern Brazil. All newborns in the city's hospitals were enrolled in 1982. The subjects have been followed up for several times in childhood. At age 18, 79% of all males were followed, and 2083 blood samples were available. Adjusted analyses controlled for household assets index, family income, parental schooling at birth, maternal smoking during pregnancy and breastfeeding duration.

Results:

Birth weight for gestational age and weight gain in the first 20 months was not associated with blood lipid levels in adolescence. On the other hand, those subjects whose weight gain from 20 to 42 months of age was faster than that predicted from birth weight and weight-for-age z-score at the mean age of 20 months had lower high-density lipoprotein cholesterol (HDL) cholesterol [−0.78 (95% confidence interval: −1.28; −0.29)] and higher very low-density lipoprotein cholesterol (VLDL) and low-density lipoprotein cholesterol (LDL)/HDL ratio in adolescence. After controlling for current body mass index (BMI), the regression coefficient for HDL cholesterol decreased from −0.78 mg/dL to −0.29 mg/dL (95% confidence interval: −1.00 to 0.05).

Conclusion:

Weight gain from 2 to 4 years is related to an atherogenic lipid profile in adolescence and this association is mediated by current BMI.

Intergenerational effect of weight gain in childhood on offspring birthweight

Background Some studies suggest that weight gain in childhood may increase the risk of chronic diseases in adulthood, and recent studies have noticed that the timing of weight gain may be related to its long-term consequence. However, weight gain in childhood has clear short-term benefits, and the literature on the pro and cons of weight gain in childhood is limited.

Methods In 1982, all 5914 hospital births (over 99% of all deliveries) occurring in Pelotas, Southern Brazil, were identified and studied prospectively on several occasions. In 2004–05, we attempted to trace the whole cohort and information on offspring birthweight was collected. Conditional growth modelling was used to assess the association between offspring birthweight and weight gain from birth to 20 months, and from 20 to 42 months.

Results In 2004–05, we interviewed 4297 subjects, with a follow-up rate of 77.4%. This manuscript includes data from 848 women who had already delivered a child and 525 men who were fathers at the mean age of 23 years. Maternal birthweight, weight and length for age Z-score at 20 months of age were positively associated with next-generation birthweight, whereas paternal variables were not related to the outcome. Conditional growth modelling analyses showed that women whose weight gain in the first 20 months of life was faster than predicted had heavier babies, whereas paternal weight gain was not associated. The association was strongest for mothers whose birthweight for gestational age was in the lowest tertile.

Conclusion Maternal, but not paternal birthweight and weight gain in early childhood are positively associated with next-generation birthweight.

Impact of glucose metabolism and birth size on cognitive performance in elderly subjects

AIMS

We aimed to investigate the impact of diabetes and impaired glucose tolerance on cognitive performance and to explore the association between birth weight and cognitive performance among diabetic subjects.

METHODS

We performed a standard oral glucose tolerance test and a computerised test for assessment of cognitive performance (CogState) in 1243 subjects; 173 of them had type 2 diabetes. At the time of cognitive testing the mean age of the subjects was 64 years. Subjects with type 1 diabetes or a history of stroke were excluded.

RESULTS

Subjects with known diabetes performed significantly poorer in cognitive tasks measuring visual attention, working memory and episodic learning than subjects with normal glucose tolerance. Subjects with newly diagnosed diabetes or milder impairments in glucose regulation did not differ from the normoglycaemic group. A low birth weight enhanced the association between diabetes and poor performance in the working memory and episodic learning tasks.

CONCLUSIONS

Poorer cognitive performance was associated with known type 2 diabetes but not with newly diagnosed diabetes or milder impairments in glucose regulation. Low birth weight was found to be an additional vulnerability factor enhancing cognitive decline in diabetic subjects.

The initiatives and outcomes for cardiovascular risks that can be achieved through paediatric counselling

PURPOSE OF REVIEW

Atherosclerosis is a result of a lifelong process. Obesity is associated with increased serum levels of inflammatory markers in children and adolescents like in adults, promoting coronary heart disease risk in an increasing proportion of young adults. Dietary patterns have a central role in the development of coronary heart disease through effects on serum lipids and development of body fatness. It is the purpose of this review to describe progress in this field.

RECENT FINDINGS

The supervised counselling aiming at low saturated fat intake by children decreases serum total and low-density lipoprotein (LDL) cholesterol values significantly and keeps them at lower level through childhood. It is not associated with abnormal growth or defects in cognitive or pubertal development. Coronary heart disease risk factor levels measured in childhood markedly influence vascular function and structure.

SUMMARY

To diminish the risk of premature atherosclerosis, the prime target in counselling of young children and their parents should be a change in fat quality rather than fat quantity. However, to prevent obesity, excessive consumption of total fat and sucrose needs to be avoided. Early commencement of statin therapy in children and adolescents suffering from familial hypercholesterolemia is beneficial in prevention of vascular atherosclerosis.

Genome-wide association analysis of metabolic traits in a birth cohort from a founder population

Genome-wide association studies (GWAS) of longitudinal birth cohorts enable joint investigation of environmental and genetic influences on complex traits. We report GWAS results for nine quantitative metabolic traits (triglycerides, high-density lipoprotein, low-density lipoprotein, glucose, insulin, C-reactive protein, body mass index, and systolic and diastolic blood pressure) in the Northern Finland Birth Cohort 1966 (NFBC1966), drawn from the most genetically isolated Finnish regions. We replicate most previously reported associations for these traits and identify nine new associations, several of which highlight genes with metabolic functions: high-density lipoprotein with NR1H3 (LXRA), low-density lipoprotein with AR and FADS1-FADS2, glucose with MTNR1B, and insulin with PANK1. Two of these new associations emerged after adjustment of results for body mass index. Gene-environment interaction analyses suggested additional associations, which will require validation in larger samples. The currently identified loci, together with quantified environmental exposures, explain little of the trait variation in NFBC1966. The association observed between low-density lipoprotein and an infrequent variant in AR suggests the potential of such a cohort for identifying associations with both common, low-impact and rarer, high-impact quantitative trait loci.

Downward percentile crossing as an indicator of an adverse prenatal environment

BACKGROUND

Postnatal health sequelae of low birth weight have been attributed to 'poor fetal growth' from inferred adverse prenatal environments; risks augmented by infant growth rates. Identifying prenatal growth-restricting events is essential to clarify pathways and mechanisms of fetal growth.

AIM

The specific aim of this investigation was to examine whether an episode of preterm labor may compromise fetal growth.

SUBJECTS AND METHODS

Fetal size at the end of the second trimester and birth were compared among women with uncomplicated pregnancies (n = 3167) and those who experienced an episode of preterm labor (<37 weeks) and subsequently delivered at term (> or =37 weeks, n = 147). Fetal weight estimated from ultrasound measures, and changes in weight standard scores across the third trimester investigated significant centile crossing (>0.67 standard deviation score change).

RESULTS

Fetuses delivered at term after an episode of preterm labor were smaller at birth relative to their peers than at the end of the second trimester, and were 47% more likely to experience clinically significant downward centile crossing (p < 0.05) than their peers (OR 1.47, 95% CI 1.04-2.07).

CONCLUSION

An episode of preterm labor may signal an adverse prenatal environment for term-delivered neonates. Epidemiologically silent events in the natural history of pregnancy are an understudied source of fetal growth compromise as inferred by small birth size among peers.

Body mass index during childhood and adult body composition in men and women aged 56-70 y

BACKGROUND

The relation between the change in body mass index (BMI) through childhood and body composition in adult life is important because body composition is known to affect adult health.

OBJECTIVE

The objective was to examine how the change in BMI throughout childhood is related to adult lean and fat mass.

DESIGN

We examined how the change in BMI in childhood was related to adult body composition in 885 men and 1032 women born during 1934-1944, whose weights and heights during childhood were recorded serially. Adult lean and fat mass were measured by bioelectrical impedance with an 8-polar tactile electrode system.

RESULTS

In these 56-70-y-old men and women, adult lean body mass index (lean mass/height(2); in kg/m(2)) was positively associated with BMI at birth (0.24 and 0.20 higher for each 1-SD increase in BMI at birth, respectively) and with more rapid gain in BMI from birth to 1 y (0.17 and 0.22), 1-2 y (0.21 and 0.20), 2-7 y (0.44 and 0.46), and 7-11 y (0.32 and 0.26) of age. Fat mass index (fat mass/height(2)) was positively associated with more rapid increases in BMI between 2 and 11 y of age.

CONCLUSIONS

Rapid gain in BMI before the age of 2 y increased adult lean body mass without excess fat accumulation, whereas rapid gain in BMI in later childhood, despite the concurrent rise in lean mass, resulted in relatively larger increases in fat mass.