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Biomedical subjects

Tim J Cole

Publications and source records attributed to Tim J Cole.

At least 37 records · Page 2Linked to original sources
PubMed2005

The role of growth hormone in determining birth size and early postnatal growth, using congenital growth hormone deficiency (GHD) as a model.

OBJECTIVE: The role of GH in early human growth is unclear. Congenital GH deficiency (CGHD) provides a useful tool to explore this putative role. We have assessed the effects of CGHD on birth size and early postnatal growth, and the further impact of the presence of additional pituitary hormone deficiencies and midline brain defects on these parameters. DESIGN, PATIENTS AND MEASUREMENTS: Weight, length and BMI expressed as standard deviation scores (SDS), over the first two years of life, were retrospectively compared in 44 GH-deficient children (M:F 26 : 18). Thirty-eight of 44 patients underwent GH provocation testing and all patients had neuro-imaging of the brain. The patients were divided into three groups of increasing phenotypic complexity {group A [n = 12, isolated GHD, no midline defects], group B [n = 10, combined pituitary hormone deficiency (CPHD); no midline defects], group C (n = 22, CPHD with midline defects)}. RESULTS: Mean birth weight, length and BMI SDS were -0.4, -0.9 and +0.1 SDS, respectively. The differences were significant for weight (P = 0.03) and BMI (P = 0.003), but not length (P = 0.3) SDS, between groups A and C. Of the three groups, group A had a lower weight and BMI SDS than group C. The prevalence of postnatal complications (n = 25) was significantly different in the three groups [group A (8%), group B (80%), group C (73%); P < 0.001] and particularly between patients with isolated GH deficiency (IGHD) (group A) and CPHD (groups B and C; P < 0.0001). No patients in group A presented with neonatal hypoglycaemia as compared with 70% of those in group B and 59% in group C (P = 0.001). A reduced length SDS was observed in all patients within 6 months of birth and the reduction was greatest in group B (P = 0.03). Group C remained significantly (P < 0.05) heavier at 12, 18 and 24 months compared to group A. BMI SDS was significantly (P < 0.05) greater at all study points in CPHD patients (groups B and C) as compared with IGHD. Serum GH concentrations at testing did not correlate significantly with birth length (r = -0.08, P = 0.7), birth weight (r = -0.08, P = 0.6) or the age at induction of GH treatment (r = 0.12, P = 0.5). There were no significant differences between peak serum GH concentrations in patients in groups A (7.8 +/- 6.3 mU/l), B (3.9 +/- 4.8 mU/l) or C (8.7 +/- 5.4 mU/l). CONCLUSIONS: Length, weight and BMI data from our study groups suggest that GH per se has a minimal effect on intrauterine growth but a significant effect during the infancy period. Early growth may also be influenced by the complexity of the hypopituitary phenotype reflected by the presence of additional pituitary hormone deficiencies and midline forebrain defects.

Adrenocorticotropic Hormone↗
PubMed2004

Breastmilk feeding and lipoprotein profile in adolescents born preterm: follow-up of a prospective randomised study.

BACKGROUND: Breastfeeding is associated with reduced cholesterol concentration later in life, but previous studies have not used random assignment of infant diet with prospective follow-up. We tested the hypothesis that breastmilk feeding benefits the lipoprotein profile in adolescents born preterm, in whom randomisation to different diets at birth is feasible. METHODS: 926 infants born preterm were randomly assigned in two parallel trials to receive (trial 1) donated banked breastmilk or preterm formula, or (trial 2) standard term formula or preterm formula, as sole diet or as supplements to mother's milk in both trials. We followed up 216 participants at age 13-16 years and measured ratio of low-density to high-density lipoprotein cholesterol (LDL to HDL), ratio of apolipoprotein B to apolipoprotein A-1 (apoB to apoA-1), and concentration of C-reactive protein (CRP; a measure of the inflammatory process associated with atherosclerosis). RESULTS: Adolescents who had been randomised to banked breastmilk had a lower CRP concentration (p=0.006) and LDL to HDL ratio (mean difference 0.34 [14% lower], 95% CI -0.67 to -0.01; p=0.04) than those given preterm formula. A greater proportion of human milk intake in infancy was associated with lower ratios of LDL to HDL (p=0.03) and apoB to apoA-1 (p=0.004)--independent of gestation and potential confounding factors--and with lower CRP concentration (p=0.03). CRP concentration correlated with the two lipoprotein ratios (p<0.0001 and p=0.003, respectively). INTERPRETATION: Our data provide experimental evidence for the long-term benefits of breastmilk feeding on the risk of atherosclerosis.

Adolescent↗
PubMed2004

Is slower early growth beneficial for long-term cardiovascular health?

BACKGROUND: Accelerated neonatal growth increases the later propensity to cardiovascular disease (CVD) in animals, whereas slower growth is thought to have a beneficial effect. To test this hypothesis in humans, we measured flow-mediated endothelium-dependent dilation (FMD) in a population subject to slower early growth and in healthy controls. METHODS AND RESULTS: High-resolution vascular ultrasound was used to measure the change in brachial artery diameter in response to reactive hyperemia in adolescents age 13 to 16 years who were either part of a cohort born preterm and followed up prospectively (n=216) or controls born at term (n=61). Greater weight gain or linear growth in the first 2 weeks postnatally was associated with lower FMD at adolescence (regression coefficient, -0.026-mm change in mean arterial diameter per 100-g increase in weight; 95% CI, -0.040 to -0.012 mm; P=0.0003) independent of birthweight and potential confounding factors. Mean FMD in the half of the preterm population with the lowest rates of early growth was higher than in both the half with the greatest growth (P=0.001) and subjects born at term (P=0.03). CONCLUSIONS: FMD was 4% lower in adolescents with the highest compared with the lowest rate of weight gain in the first 2 weeks after birth, a substantial negative effect similar to that for insulin-dependent diabetes mellitus or smoking in adults. Our findings are consistent with the adverse effects of accelerated neonatal growth on long-term cardiovascular health and suggest that postnatal growth patterns could explain the previously reported association between birthweight and later CVD.

Birth Weight↗
PubMed2004

Prevalence of overweight and obesity among young people in Great Britain.

OBJECTIVE: To determine the prevalence of overweight and obesity in British young people (4-18 years) in 1997. DESIGN: Cross-sectional analysis of the National Diet and Nutrition Survey of young people. SETTING: Great Britain. SUBJECTS: Nationally representative sample of 1836 young people (age 4-18 years). RESULTS: The prevalence of obesity based on body mass index (weight/height(2)) and the International Obesity Task Force cut-offs was 4.0%, with a further 15.4% identified as overweight. Asians were almost four times as likely to be obese as white subjects (13.6 vs. 3.5%, P<0.001). Among white subjects there was no significant difference in the prevalence of obesity between girls and boys, or with age. The risk of obesity was significantly higher in subjects from social classes IV and V than from social classes I-III (6.5 vs. 2.7%, P=0.003). Subjects living in Scotland and Wales were significantly more likely to be obese than those in England (7.6 and 6.5 vs. 2.9%, respectively, P<0.01). Multiple logistic regression showed that, among white subjects, those in social classes IV and V living in Wales and Scotland were three times more likely to be obese than the other children in the survey (odds ratio 3.3, 95% confidence interval 1.1-9.8). CONCLUSION: These data provide information on the national prevalence of overweight and obesity in Great Britain and baseline data from which to monitor future trends. This analysis provides important demographic information on those most at risk of obesity, which may be used to inform public health strategies to prevent obesity in young people.

Adolescent↗
PubMed2004

Prematurity and reduced body fatness at 8-12 y of age.

BACKGROUND: Increasing evidence suggests that body composition, an important factor influencing morbidity and mortality in adult life, might be programmed by early growth and nutrition. Children born preterm remain shorter and lighter than their term-born peers during childhood, but it is unclear whether the size difference is associated with altered body composition. OBJECTIVE: We tested the hypothesis that both fat mass (FM) and fat-free mass (FFM) are proportionately lower in children born preterm than in children born at term. DESIGN: A total of 497 children born preterm and 95 children born at term were studied at 8-12 y of age. Body composition was determined with the use of skinfold thicknesses and dual-energy X-ray absorptiometry (in 200 preterm and 95 term children). FM and FFM were normalized for height to give fat mass index (FMI) and fat-free mass index (FFMI), respectively. RESULTS: Children born preterm were significantly lighter than those born at term and had lower FM and FFM. However, FMI was significantly lower in preterm children, whereas FFMI was not. FMI was also significantly lower in boys than in girls and in children with higher activity levels. Additional data available for the preterm group showed no association between birth weight, gestational age, or neonatal diet and later FMI or FFMI. CONCLUSIONS: The smaller size of children born preterm than of children born at term is associated with lower FM but not FFM when normalized for height. We hypothesize that this could result in a reduction in the risk of obesity and related diseases during adult life.

Absorptiometry, Photon↗
PubMed2004

Modeling postnatal exposures and their interactions with birth size.

The fetal origins of adult disease hypothesis postulates that the inverse association between birth weight and later adverse outcome reflects fetal programming that increases the risk of later disease. However, low birth weight is associated with catch-up after birth, and weight gain is itself a risk factor for later disease. It is difficult to disentangle the effects on outcome of the size and growth components of weight change through time. This paper presents the life course plot, a device to display both size and growth effects simultaneously. It is based on the multiple-regression analysis of the outcome on the various weights, expressed as z-scores, and the plot displays the coefficients plotted against the corresponding ages of measurement. Examples from Brazil (Pelotas) and the Phillippines (Cebu) relate blood pressure in adolescence to weight through childhood. They show small inverse weight effects in infancy, but early weight is less important than weight and weight gain during adolescence. In addition, birth length in the Cebu study affects the strength of the relationship between weight and blood pressure in adolescence. This suggests a fetal programming effect, with children who were relatively long at birth having a more sensitive relationship between blood pressure and weight at age 15. Whether this is a good or a bad thing is not immediately clear.

Adolescent↗
PubMed2003

Low nutrient intake and early growth for later insulin resistance in adolescents born preterm.

BACKGROUND: In animals, acceleration of neonatal growth is thought to increase the later propensity to insulin resistance and non-insulin-dependent diabetes, whereas slow growth as a consequence of undernutrition is thought to have a beneficial effect. To test this hypothesis in people, we measured fasting concentrations of 32-33 split proinsulin, a marker of insulin resistance, in adolescents born preterm who had participated in randomised intervention trials of neonatal nutrition, and in adolescents born at term. METHODS: We determined fasting 32-33 split proinsulin concentration in participants aged 13-16 years born preterm and randomised to receive a nutrient-enriched or lower-nutrient diet (n=216) or in a reference group born at term (n=61). FINDINGS: Fasting 32-33 split proinsulin concentration was greater in children given a nutrient-enriched diet (geometric mean 7.2 pmol/L, 95% CI 6.4-8.1) than in those given the lower-nutrient diet (5.9 pmol/L [5.2-6.4]; mean difference 20.6% [5.0-36.3]; p=0.01). Healthy babies born at term had similar fasting 32-33 split proinsulin concentrations (6.9 pmol/L; 6.0-8.2) to the nutrient-enriched group. In non-randomised analyses, fasting 32-33 split proinsulin concentration was associated with greater weight gain the first 2 weeks of life (13.2% [5.4-20.9] change per 100 g weight increase; p=0.001) independent of birthweight, gestation, neonatal morbidity, and demographic, anthropometric, and socioeconomic factors. INTERPRETATION: Our results suggest that relative undernutrition early in life in children born preterm may have beneficial effects on insulin resistance.

Adolescent↗
PubMed2003

Central overweight and obesity in British youth aged 11-16 years: cross sectional surveys of waist circumference.

OBJECTIVE: To compare changes over time in waist circumference (a measure of central fatness) and body mass index (a measure of overall obesity) in British youth. DESIGN: Representative cross sectional surveys in 1977, 1987, and 1997. SETTING: Great Britain. PARTICIPANTS: Young people aged 11-16 years surveyed in 1977 (boys) and 1987 (girls) for the British Standards Institute (n=3784) and in 1997 (both sexes) for the national diet and nutrition survey (n=776). MAIN OUTCOME MEASURES: Waist circumference, expressed as a standard deviation score using the first survey as reference, and body mass index (weight(kg)/height(m)2), expressed as a standard deviation score against the British 1990 revised reference. Overweight and obesity were defined as the measurement exceeding the 91st and 98th centile, respectively. RESULTS: Waist circumference increased sharply over the period between surveys (mean increases for boys and girls, 6.9 and 6.2 cm, or 0.84 and 1.02 SD score units, P<0.0001). In centile terms, waist circumference increased more in girls than in boys. Increases in body mass index were smaller and similar by sex (means 1.5 and 1.6, or 0.47 and 0.53 SD score units, P<0.0001). Waist circumference in 1997 exceeded the 91st centile in 28% (n=110) of boys and 38% (n=147) of girls (against 9% for both sexes in 1977-87, P<0.0001), whereas 14% (n=54) and 17% (n=68), respectively, exceeded the 98th centile (3% in 1977-87, P<0.0001). The corresponding rates for body mass index in 1997 were 21% (n=80) of boys and 17% (n=67) of girls exceeding the 91st centile (8% and 6% in 1977-87) and 10% (n=39) and 8% (n=32) exceeding the 98th centile (3% and 2% in 1977-87). CONCLUSIONS: Trends in waist circumference during the past 10-20 years have greatly exceeded those in body mass index, particularly in girls, showing that body mass index is a poor proxy for central fatness. Body mass index has therefore systematically underestimated the prevalence of obesity in young people.

Adolescent↗
PubMed2003

Rapid child growth raises blood pressure in adolescent boys who were thin at birth.

Catch-up growth in previously growth-restricted children is a suggested risk factor for chronic disease risk. We use data from 2026 Filipino adolescents to identify periods of growth that matter more for risk of high blood pressure (BP). Subjects were drawn from the Cebu Longitudinal Health and Nutrition Survey, which enrolled pregnant women and followed up their offspring through age 14 to 16 years. High BP was defined as the top 10% of residuals from gender-specific regressions of systolic and diastolic BP on age and height. After controlling for birth length, current body mass index, age, and height, the odds of high BP in males were significantly decreased with each kilogram increase in birth weight. The highest odds of elevated BP occurred among males who were relatively thin at birth but relatively heavy as adolescents. Larger weight increments from birth to 2 years decreased the odds of high BP in boys, whereas larger increments from 8 to 11 and 11 to 16 years increased the odds of high BP. Thinness at birth significantly interacted with growth rate after age 8, such that a high rate of weight gain increased risk only among boys who were in the lower two thirds of the body mass index distribution at birth. Results in girls indicated small or no effects of early growth. The synergistic effect on adolescent BP of rapid weight gain from late childhood into adolescence with thinness at birth is further evidence of fetal programming of BP in males and suggests long-term health risks associated with rapid growth, even in the absence of obesity.

Adolescent↗
PubMed2003

Programming of lean body mass: a link between birth weight, obesity, and cardiovascular disease?

BACKGROUND: A high birth weight has been suggested to increase the later risk of obesity, as measured by body mass index, but, paradoxically, to decrease the later propensity to cardiovascular disease. Programming of more lean tissue rather than fat mass by a high birth weight might explain this paradox and also explain the association of birth weight with later body mass index. This concept has been inadequately tested. OBJECTIVE: The objective was to test the hypothesis that a high birth weight programs a greater proportion of lean mass in children and adolescents. DESIGN: Body fat mass and fat-free mass were assessed by both skinfold-thickness measurement and bioelectrical impedance analysis in adolescents aged 13-16 y (n = 78) who were part of a study that investigated the early origins of cardiovascular disease. Body composition was assessed by dual-energy X-ray absorptiometry in a separate group of younger children. RESULTS: An increase in birth weight of 1 SD was significantly associated with a 0.9-1.4-kg (2-3%) increase in fat-free mass in adolescents but not with an increase in fat mass. This association was independent of age, sex, height, pubertal stage, socioeconomic status, and physical activity. Similar observations were made in younger children. CONCLUSIONS: Our data support the hypothesis that fetal growth, measured by birth weight, programs lean mass later in life. Our observations may therefore explain the association of birth weight with body mass index and have implications for the early origins of both obesity and cardiovascular disease.

Absorptiometry, Photon↗
PubMed2003

Effect of a calcium and exercise intervention on the bone mineral status of 16-18-y-old adolescent girls.

BACKGROUND: Osteoporosis may be prevented or delayed by maximizing peak bone mass through diet modification and physical activity during adolescence. OBJECTIVE: We studied whether increases in calcium intake and physical activity effectively increase the bone mineral status of adolescent girls aged 16-18 y. DESIGN: We conducted a 15.5-mo study of calcium supplementation (1000 mg Ca/d as carbonate) in 144 adolescent girls aged 17.3 +/- 0.3 y ( +/- SD). The subjects were randomly allocated to an exercise (three 45-min exercise-to-music classes/wk during term time) or nonexercise group. Dual-energy X-ray absorptiometry of the whole body, spine, forearm, and hip was performed before and after intervention. RESULTS: The mean (+/- SD) percentage of subjects compliant with supplement taking was 70 +/- 27% and with exercise class attendance was 36 +/- 25%. Baseline calcium intake was 938 +/- 411 mg/d. Calcium supplementation significantly increased size-adjusted bone mineral content. The effect was stronger in subjects with good compliance (percentage difference +/- SE): whole body, 0.8 +/- 0.3% (P < or = 0.01); lumbar spine, 1.9 +/- 0.5% (P < or = 0.001); ultradistal radius, 1.3 +/- 0.6% (P < or = 0.05); total hip, 2.7 +/- 0.6% (P < or = 0.001); femoral neck, 2.2 +/- 0.7% (P < or = 0.001); trochanter, 4.8 +/- 0.9% (P < or = 0.001). Attendance at > 50% of the exercise sessions was significant at the total hip (1.4 +/- 0.7%; P < or = 0.05) and trochanter (2.6 +/- 1.2%; P < or = 0.05). CONCLUSIONS: Calcium supplementation and exercise enhanced bone mineral status in adolescent girls. Whether this is a lasting benefit, leading to the optimization of peak bone mass and a reduction in fracture risk, needs to be determined.

Absorptiometry, Photon↗
PubMed2003

Primary vesicoureteric reflux as a predictor of renal damage in children hospitalized with urinary tract infection: a systematic review and meta-analysis.

Renal parenchymal disease after urinary tract infection (UTI) has been associated with the development of hypertension and renal functional impairment. A systematic literature review and meta-analysis was performed to determine how effectively the finding of primary vesicoureteric reflux (VUR) on micturating cystography (MCU) in children hospitalized with UTI predicted renal parenchymal disease on (99m)Technetium-dimercaptosuccinic acid ((99m)Tc-DMSA) scintigraphy. Medline, Embase, and PubMed were use to find reports with original data for children hospitalized with bacteriologically-proven UTI who had undergone both MCU and (99m)Tc-DMSA scintigraphy, and which also reported both positive and negative results of these tests. A meta-analysis of likelihood ratios positive and negative for MCU was then performed, including tests for heterogeneity. Twelve valid studies were found, seven with data for 537 children, with a positive (99m)Tc-DMSA scan prevalence of 59% overall, and seven studies with data for 1062 kidneys, with a positive (99m)Tc-DMSA scan prevalence of 36%. The likelihood ratio positive for MCU was 1.96 (95% CI, 1.51 to 2.54) for children, and 2.34 (1.53 to 3.57) for kidneys. The likelihood ratio negative was 0.71 (0.58 to 0.85) for children and 0.72 (0.61 to 0.86) for kidneys. There was evidence of heterogeneity. The meta-analysis showed that a positive MCU increases the risk of renal damage in hospitalized UTI patients by about 20%, whereas a negative MCU increases the chance of no renal involvement by just 8%. VUR is hence a weak predictor of renal damage in pediatric patients hospitalized with UTI. Physicians should be aware of the limitations of using MCU-detected primary VUR as an effective screening test for renal damage in this population. Furthermore, the pathogenesis of renal damage in such patients is probably complex because it is often detected without demonstrable VUR.

Child, Hospitalized↗
PubMed2002

Influence of leptin on arterial distensibility: a novel link between obesity and cardiovascular disease?

BACKGROUND: The mechanisms by which obesity increases the risk of atherosclerotic cardiovascular disease (CVD) are poorly understood. In experimental models, leptin, a hormone produced by adipose tissue, has been shown adversely to affect vascular health. Therefore, we tested the hypothesis that high leptin concentrations are associated with lower arterial distensibility, an index of circulatory function relevant to the atherosclerotic process. METHODS AND RESULTS: Noninvasive, high-resolution, vascular ultrasound was used to measure brachial artery distensibility in 294 healthy adolescents (aged 13 to 16 years) who had a broad range of body mass indexes. Fat mass was measured by bioelectric impedance analysis; fasting serum leptin concentration by radioimmunoassay; and lipid profile, fasting insulin, glucose, and C-reactive protein concentrations by standard laboratory techniques. Higher leptin concentrations were associated with impaired arterial distensibility (regression coefficient, -1.3% change in arterial distension per 10% increase in leptin; 95% CI, -1.9% to -0.8%; P<0.001). This association was independent of fat mass, blood pressure, and C-reactive protein, fasting insulin, or LDL cholesterol concentrations. CONCLUSIONS: Elevation in leptin was associated with impaired vascular function, independent of the metabolic and inflammatory disturbances associated with obesity. Our observations are consistent with data from experimental models and suggest that high leptin concentration is an important mechanism for the adverse influence of body fatness on CVD.

Adipose Tissue↗
PubMed2002

Sex-specific prediction equations for Vmax(FRC) in infancy: a multicenter collaborative study.

Measurements of maximal flow at functional residual capacity (Vmax(FRC)) from partial forced expiratory maneuvers remain the most popular method for assessing small airway function in infants and young children. However, the lack of appropriate reference data that are both applicable outside the centers that developed them and reflect the normal variability between healthy subjects has limited interpretation of Vmax(FRC) results in both clinical practice and research. To address this problem, we collated Vmax(FRC) data from 459 healthy infants (226 boys) tested on 654 occasions during the first 20 months of life from three collaborating centers. Multiple linear regression analysis indicated that sex, age, and length were important predictors of Vmax (FRC), which was, on average, 20% higher in girls than in boys during the first 9 months of life. (Vmax(FRC))0.5 (ml x second(-1)) = 4.22 + 0.00210 x length2 (cm) for boys (RSD = 3.01; R2 = 0.48), and -1.23 + 0.242 x length for girls (RSD = 2.72; R2 = 0.49). Alternative models incorporating both age and length z scores are also described. Failure to use sex-specific prediction equations for Vmax(FRC) may preclude detection of clinically significant changes in girls and lead to false reports of diminished airway function in boys. Appropriate use of z scores, which indicate a "normal" range (z scores of 0 +/- 2) for Vmax(FRC), during infancy should also improve interpretation of both clinical and research studies.

Body Constitution↗
PubMed2002

Birth weight and environmental heat load: a between-population analysis.

Low birth weight, a major cause of infant morbidity and mortality, is caused by different factors in Western and developing-country populations. In addition to differing in terms of ethnicity, maternal size, maternal nutritional status, and disease load, developing-country and Western populations are also characterized by different environmental heat loads. Thermodynamic theory predicts that heat stress is mitigated by reduced size of both mother and offspring, and therefore generates the hypothesis that reduced birth weight may be an adaptation to environmental heat load. The aim of this study was to test the hypothesis that environmental heat load is associated with between-population variability in birth weight. Data on birth weight and thermal environment were obtained from the literature for 140 populations. Further data on several physical, social, and biological confounders were also collated. After adjusting for confounding factors, of which only maternal height and per capita gross domestic product were statistically significant, heat stress showed a significant inverse relationship with birth weight in 108 populations, accounting for an additional 9.6% of the between-population variance. Though based on data collected from more than one source, these results are consistent with the hypothesis that heat stress is inversely associated with birth weight, as previously reported for within-population studies. Further studies are needed to establish to what extent heat stress is a determinant of low birth weight in developing countries.

Adaptation, Physiological↗
PubMed2002

Early nutrition and leptin concentrations in later life.

BACKGROUND: Formula feeding or overweight in infancy may increase the later risk of obesity, but the mechanisms involved are uncertain. Because obesity is associated with high leptin concentrations relative to fat mass, programming of leptin concentrations may be one mechanism by which early nutrition influences later obesity. OBJECTIVE: We tested the hypothesis that high nutrient intake or formula feeding in infancy programs greater leptin concentrations relative to fat mass in later life. DESIGN: Serum leptin concentrations were measured by radioimmunoassay in 197 adolescents aged 13-16 y who were born preterm and randomly assigned at birth to receive either a nutrient-enriched preterm formula or banked donated breast milk (trial 1) or a preterm formula or a standard formula (trial 2). Fat mass was estimated with the use of bioelectrical impedance analysis. RESULTS: After combining the results of trials 1 and 2 as planned, the ratio of leptin to fat mass was significantly greater in the children who received the preterm formula (geometric : 0.84 microg x L(-1) x kg(-1)) than in those who received standard formula or banked breast milk (0.62 microg x L(-1) x kg(-1); mean difference: 30.8%; 95% CI for difference: 8.4%, 53.2%; P = 0.007). The difference between the diet groups remained significant after adjustment for age, sex, Tanner stage, social class, and fat mass. Human milk intake was significantly associated with lower leptin concentrations relative to fat mass in adolescence (P = 0.023), independent of potential confounding factors. CONCLUSION: Programming of relative leptin concentrations by early diet may be one mechanism that links early nutrition with later obesity.

Adolescent↗
PubMed2002

Bone mineral contents and plasma osteocalcin concentrations of Gambian children 12 and 24 mo after the withdrawal of a calcium supplement.

BACKGROUND: Our randomized, placebo-controlled supplementation study of 160 rural Gambian children aged 8.3-11.9 y showed that an increase in calcium intake of 714 mg/d for 12 mo resulted in a 5% increase in forearm bone mineral acquisition and a 22% decrease in plasma osteocalcin concentration, a bone formation marker, but had no effect on height or bone dimensions. OBJECTIVE: We investigated whether these results were sustained after supplement withdrawal. DESIGN: All participants were followed up 12 (FU1) and 24 (FU2) mo after supplementation ended. Bone mineral content (BMC), bone mineral density (BMD), and BMC adjusted for bone width, body weight, and height (size-adjusted BMC) were measured at the midshaft and distal radius. Plasma osteocalcin concentration was measured at FU1. RESULTS: At follow-up, the calcium group had greater bone mineral status than did the placebo group at the midshaft radius (mean difference +/- SE), FU1: BMC (4.7 +/- 1.6%; P = 0.004), BMD (5.1 +/- 1.1%; P </= 0.0001), size-adjusted BMC (5.0 +/- 1.1%; P </= 0.0001); FU2: BMC (3.8 +/- 1.6%; P = 0.02), BMD (2.7 +/- 1.3%; P = 0.04), size-adjusted BMC (2.5 +/- 1.3%; P = 0.06). Similar differentials were observed at the distal radius but were not significant. No significant differences in plasma osteocalcin concentrations (FU1: -0.5 +/- 6.5%; P = 0.9) were observed between groups. CONCLUSION: Although some of the effects of calcium supplementation were still evident at follow-up, further studies are required to determine whether short-term increases in calcium intake have lasting benefits for Gambian children.

Body Height↗