Bone mineralisation in ex-preterm infants aged 8 years

In preterm infants, in whom perinatal mineralisation deficits are common, there is little information on long-term bone mineralisation. Using a Hologic QDR 1000 dual energy X-ray absorptiometer, bone mineral content and density (BMC and BMD) were measured in lumbar, spine, forearm and hip in 46 ex- preterm infants <32 weeks gestation together with controls at 8 years of age. Height and weight were recorded, as was history of bone fracture. Preterm infants were shorter by 4.9 cm (95% CI, 2.4 – 7.3) and lighter by 2.6 kg (95% CI, 0.7 – 4.4). BMC for all sites measured was significantly lower in the preterm group, but did not remain so when adjusted for height and weight. BMD was significantly reduced in the hip of the preterm group. Prolonged ventilation was associated with the lowest BMC and duration of preterm formula feeding correlated with higher BMC. Accidental fractures were less common in the preterm group. Conclusion Ex preterm infants have significant reduction in bone mineral mass commensurate with their reduced growth and reduced bone mineral density in their hips. Received: 16 June 1997 / Accepted in revised form: 16 May 1998     

Measurement of bone mineral density by dual energy X-ray absorptiometry in preterm infants fed human milk or formula

Bone mineralization of healthy preterm infants fed human milk were compared with that of similar fed preterm formula. Bone mineralization was studied by dual energy X-ray absorptiometry in 43 preterm infants divided into two groups; 21 preterm infants were fed with maternal breast milk and 22 preterm infants with a preterm formula containing 70 mg calcium and 35 mg phosphorus per decilitre. Conclusion Preterm infants fed breast milk had lower bone mineral density than the preterm formula-fed group. Fortifying preterm human milk with calcium and phosphorus will improve bone mineralization in preterm infants. Received: 26 November 1996 and in revised form: 26 August 1997 / Accepted: 9 September 1997     

Body fat, abdominal fat and body fat distribution related to cardiovascular risk factors in prepubertal children

Aim: We analysed whether total body fat (TBF), abdominal fat and body fat distribution are associated with higher composite risk factor scores for cardiovascular disease (CVD) in young children. Methods: Cross‐sectional study of 238 children aged 8–11 years. TBF and abdominal fat mass (AFM) were measured by Dual‐Energy X‐Ray Absorptiometry. TBF was expressed as a percentage of body weight (BF%). Body fat distribution was calculated as AFM/TBF. Maximal oxygen uptake (VO_2PEAK), systolic and diastolic blood pressure (SBP, DBP), and resting heart rate (RHR) were measured. Mean arterial pressure (MAP) and pulse pressure (PP) were calculated. Left atrial diameter (LA) was measured, and left ventricular mass (LVM) and relative wall thickness (RWT) were calculated. Z‐scores were calculated. Sum of z‐scores for SBP, DBP, MAP, PP, RHR, LVM, LA, RWT and ?VO_2PEAK was calculated in boys and girls, separately, and used as composite risk factor score. Results: Pearson correlations between ln BF%, ln AFM and AFM/TBF versus composite risk factor score for boys were r = 0.56, r = 0.59 and r = 0.48, all p < 0.001, and for girls r = 0.45, r = 0.50 and r = 0.48, all p < 0.001. Conclusion: Total body fat, abdominal fat and body fat distribution were all associated with higher composite risk factor scores for CVD in young children.     

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目的观察二甲双胍治疗对高胰岛素血症肥胖患儿血清脂源性激素脂联素、抵抗素、瘦素水平的影响。方法2004-01—2005-02将武汉市儿童医院和同济医院54例高胰岛素血症肥胖患儿分为轻、中度肥胖组及重度肥胖组,均以二甲双胍治疗12周,测量治疗前后体重、空腹血糖、空腹胰岛素及脂源性激素脂联素、瘦素、抵抗素的变化。结果治疗前轻、中度肥胖组和重度肥胖组高胰岛素血症患儿空腹血糖水平与健康对照组比较差异无显著性(P>0.05),血清胰岛素、瘦素、抵抗素及胰岛素抵抗指数(HOMA-IR)均高于健康对照组(P<0.01),脂联素水平明显低于健康对照组(P<0.01)。二甲双胍治疗12周后与治疗前相比,血清胰岛素水平、胰岛素抵抗指数明显降低(P<0.01),轻、中度肥胖组及重度肥胖组血清瘦素水平分别由治疗前的(24.3±1.8)μg/L、(30.2±5.1)μg/L降低为治疗后的(19.6±6.3)μg/L、(24.7±5.3)μg/L,差异有统计学意义;抵抗素水平分别由治疗前的(16.5±6.0)μg/L、(22.3±5.2)μg/L升高为(22.0±5.1)μg/L、(30.6±11.7)μg/L,差异有统计学意义;轻、中度肥胖组和重度肥胖组血清脂联素水平治疗前分别为(8.4±3.2)mg/L、(6.5±1.2)mg/L,治疗后分别为(8.9±2.3)mg/L、(7.03±3.0)mg/L,治疗前后相比,P>0.05。体重指数(BMI)下降,但差异无显著性。结论二甲双胍能显著改善肥胖患儿胰岛素抵抗。降低血清瘦素水平可能是其改善胰岛素抵抗机制之一,但在对脂源性激素脂联素、抵抗素水平的改善上,有其局限性。     

Leptin is closely related to body fat in prepubertal children aged 8-11 years

BACKGROUND: In adults and obese children, serum leptin concentrations are closely related to body fat. AIM: To investigate whether such a relationship between leptin concentrations and body fat is also evident in children with a relatively normal body composition. METHODS: The study was a cross-sectional population study in 170 Caucasian children (91 boys and 79 girls), with a mean age of 9.9+/-0.6 y (range 8.5-10.9 y) and a mean BMI of 17.4+/-2.6 (range 12.8-28.1). Serum leptin was measured and compared to total body fat as determined by dual-energy X-ray absorptiometry. RESULTS: In the whole population, serum leptin concentrations were highly correlated with total body fat (r=0.83, p<0.001). A stepwise forward multi-regression analysis revealed that the inclusion of other anthropometrical data did not add any significance to the model. Leptin concentrations were significantly higher in girls (5.2 ng/ml) than in boys (3.2 mg/ml; p=0.003). Gender differences still prevailed (p=0.007) after adjusting for number of kilograms of fat tissue. CONCLUSION: This study shows that, already at the young age of 9-11 y, an adult-like pattern of regulation of leptin exists. This indicates similar risk factor dependency of leptin across all age groups.     

Bone mineral density of the lumbar spine in very-low-birth-weight infants: a longitudinal study

To examine osteopenia in very low birth weight (VLBW) infants we used repeated dual-energy X-ray absorptiometry in a prospective study of lumbar spinal bone mineral density (BMD) in Japanese VLBW infants (birthweight 426–1498 g; n = 61, group 1) aged 40 weeks postconception to 3 years of age. Control subjects were Japanese infants with birthweight 1500–1999 g (group 2), 2000–2499 g (group 3), or more than 2500 g (group 4). BMD in group 1 during the early period after birth was very low, increased rapidly for 1 year, and then gradually increased until 3 years of age (r =  0.931, P < 0.0001). BMD at the age of 40 weeks postconception was 0.085 ± 0.026, 0.132 ± 0.039, 0.178 ± 0.042, and 0.196 ± 0.046 g/cm² in groups 1, 2, 3, and 4, respectively (P < 0.0001). However, at 1 and 2 years of age no differences were observed among the groups in BMD. Conclusion This study shows that lumbar spinal BMD in VLBW infants can normalize by the age of 2 years. Received: 12 May 1999 / Accepted: 11 October 1999     

Birth weight categorization according to gestational age does not reflect percentage body fat in term and preterm newborns

This study was performed to prove the applicability of the small-for-gestational age (SGA), appropriate-for-gestational age (AGA), and large-for-gestational age (LGA) classification depending on birth weight to predict percentage body fat (%BF) measured by dual-energy X-ray absorptiometry (DXA) in term and preterm infants. The data of 159 healthy term and preterm neonates (87 boys and 72 girls) with a gestational age at delivery of 38.4 weeks from two longitudinal studies were analyzed. Anthropometry and body composition data were assessed within the first 10 days after birth. Correlations between anthropometric parameters and fat mass measured by DXA were calculated. Prevalences of observations with low, middle, and high %BF measured by DXA were compared between SGA, AGA, and LGA groups, according to sex and gestational age. In term infants, 42.9% of the newborns with less than 10% body fat were classified to be AGA; 9.9% of all AGA newborns had less than 10% body fat. For the whole group, among the ratios investigated, the weight-length ratio (r=0.82) showed the best correlation to fat mass measured by DXA. The %BF at the time of study was higher in girls (14.75%) than in boys (11.95%). In conclusion, traditional classification based on birth weight centiles does not reflect %BF in term and preterm newborns.     

Serum levels of resistin and its correlation with adiponectin and insulin in healthy full term neonates

Resistin and adiponectin are two adipokines involved in the regulation of insulin sensitivity, and have been suggested as mediators of adult metabolic syndrome.

Aim

The aim of this study was to investigate cord blood levels of resistin, and their postnatal changes in full-term appropriate for gestational age (AGA) neonates. Interrelations between resistin, adiponectin, and insulin, and between resistin and neonatal and maternal anthropometric parameters were also assessed.

Design

Blood samples were obtained from 30 full term AGA neonates at birth and on the 4th day of life. Anthropometric variables studied included birth weight, length, body mass index (BMI), neonatal weight loss, and mother's BMI. Resistin and adiponectin were determined by ELISA, and insulin by radioimmunoassay method. Data were analyzed using Wilcoxon test and Spearman's correlation coefficient.

Results

Resistin levels were high at birth and did not change on the 4th day of life. Resistin levels were not correlated to insulin, nor adiponectin levels, nor any anthropometric parameter of neonates or their mothers. Instead, adiponectin levels increased on the 4th day of life, and were correlated to insulin levels.

Conclusion

High levels of resistin in full-term AGA neonates suggest that this hormone may play a role in maintenance of metabolic neonatal homeostasis, but its physiological significance needs further investigation.     

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目的分析中枢性性早熟(CPP)女童糖脂代谢的特点及脂联素在性早熟女童糖、脂代谢中的作用。方法浙江大学医学院附属儿童医院于2004年6~10月收治50例CPP女童,测量空腹血糖、胰岛素、甘油三酯、胆固醇、脂联素,并做葡萄糖耐量试验和胰岛素释放试验,采用总体胰岛素敏感指数(WBISI)、胰岛素抵抗指数(HOMA-IR)这2个指标来评估胰岛素敏感性和胰岛β细胞功能。并与年龄匹配的正常对照组进行比较。结果(1)CPP女童空腹胰岛素、HOMA-IR明显高于正常对照组(P<0·01)。(2)CPP女童A1组胆固醇较正常对照组明显升高(P<0·05)。(3)CPP女童体重指数(BMI)值均较正常对照组明显升高(P<0·05)。其中超重16%(8/50),肥胖8%(4/50)。(4)CPP女童脂联素均较正常对照组明显下降(P<0·01)。(5)CPP女童BMI值与WBISI显著负相关(r=-0·31,P<0·05),与HOMA-IR显著正相关(r=0·30,P<0·05),与脂联素显著负相关(r=-0·43,P<0·01)。CPP女童脂联素与WBISI显著正相关(r=0·29,P<0·05),多元回归分析显示CPP女童脂联素与WBISI、HOMA-IR无显著相关性。(6)排除12例超重加肥胖CPP女童后再分析显示A1、A2组女童空腹胰岛素、HOMA-IR仍明显高于正常对照组(P<0·01),而脂联素水平3组差异无显著性。结论(1)CPP女童存在不同程度的胰岛素抵抗,尤见于BMI值明显升高的性早熟女童。(2)肥胖或超重的性早熟女童胰岛素抵抗可能与脂联素水平下降有关。     

Body composition of preterm infants measured during the first months of life: bioelectrical impedance provides insignificant additional information compared to anthropometry alone

Detailed knowledge of body composition in preterm neonates during their later postnatal period may be important for the treatment process. However, little consideration has been given to test whether bioelectrical impedance analysis (BIA) is a useful bedside method to predict fat-free mass (FFM). The aim of the study is to assess whether BIA is a bedside method to measure FFM in preterm neonates. FFM of 118 white subjects (51 males, 67 females), mean gestational age of 30.1±3.1 weeks and birth weight of 1.26±0.47 kg, was measured at a gestational age of 38.6±3.8 weeks and actual body weight of 2.6±0.54 kg using dual energy X-ray absorptiometry (FFM_DXA). Weight (W), height (Ht), and bioelectric impedance (I) measurements were collected. Multiple regression analysis was performed to develop prediction equations to estimate FFM with impedance index (Ht²/I, cm²/Ω) and W (kg) as predictor variables. Bootstrap analysis was performed for validating the derived prediction equations. Correlations between FFM_DXA and weight were 0.96, 0.98, and 0.97 in boys, girls, and both sexes, respectively. Those between FFM_DXA and Ht²/I were: 0.73, 0.81, and 0.79. Equations used to predict FFM (kg) were for boys: and for girls: . Conclusions. In preterm neonates, weight is a more effective predictor of FFM than impedance index. The study provides a bedside procedure for estimating FFM, mainly based on anthropometric parameters rather than BIA.     

The potential of digital X-ray radiogrammetry (DXR) in the assessment of osteopenia in children with chronic inflammatory bowel disease

Background Loss of bone mass is a known complication of chronic inflammatory bowel disease (IBD) in children. The gold standard in the evaluation of bone mineral density (BMD) is dual energy X-ray absorptiometry (DXA). Objective In this preliminary study we evaluated digital X-ray radiogrammetry (DXR) which estimates BMD (DXR-BMD) from hand radiographs in children with IBD. Materials and methods A total of 26 children with IBD (10 girls, 16 boys; age range 10–18 years) underwent DXR for the calculation of DXR-BMD and metacarpal index (DXR-MCI) using the Pronosco X-posure system. The results were compared with a local reference database and correlated with the results of DXA. Results DXR-BMD was 0.36–0.56 g/cm² (median 0.46 g/cm²) in Crohn disease patients and 0.38–0.63 g/cm² (median 0.48 g/cm²) in ulcerative colitis patients. DXR-MCI was 0.29–0.49 in Crohn disease patients and 0.28–0.53 in ulcerative colitis patients. The Z-scores were reduced to <−1 SD in five Crohn disease patients and in six ulcerative colitis patients. The coefficients (r) for the correlations between DXR-BMD and DXA-BMD were 0.78 for the lumbar spine and 0.61 for the proximal femur (P<0.01), and between DXR-MCI and DXA-BMD were 0.78 for the lumbar spine and 0.51 for the proximal femur (P<0.01). Conclusions DXR seems to be able to estimate cortical osteopenia in children with chronic IBD. The DXR results showed a positive correlation with DXA results.     

Body composition,as assessed by bioelectrical impedance spectroscopy and dual-energy X-ray absorptiometry,in a healthy paediatric population

The aim of this study was to determine the level of agreement between body composition measurements by dual-energy X-ray absorptiometry (DXA), single-frequency bioelectrical impedance analysis (BIA) and multifrequency bioelectrical impedance spectroscopy (BIS). Fat-free mass (FFM), body fat mass and body fatness (percentage fat) were measured by DXA, BIA and BIS in 61 healthy children (37M, 24F, aged 10.9-13.9 y). Estimates of FFM, body fat mass and body fatness were highly correlated (r = 0.73-0.96, p < 0.0001) between the different methods. However, a Bland-Altman comparison showed wide limits of agreement between the methods. The mean differences between methods for FFM ranged from -2.31 +/- 7.76 kg to 0.48 +/- 7.58 kg. Mean differences for body fat mass ranged from 0.16 +/- 5.06 kg to 2.95 +/- 5.65 kg and for body fatness from -2.3 +/- 7.8% to 0.8 +/- 9.3%. Calculations of body composition with BIS were not superior to BIA. However, BIA overestimated fat mass in lean, subjects and underestimated fat mass in overweight subjects more than BIS, compared with DXA. CONCLUSION: The methods used provided estimates of FFM, body fat mass and body fatness that were highly correlated in a population of healthy children. However, the large limits of agreement derived from the Bland-Altman procedure suggest that the methods should not be used interchangeably.     

Depression scale scores in 8-17-year-olds: effects of age and gender

BACKGROUND: The excess of unipolar depression in females emerges in adolescence. However, studies of age effects on depression scale scores have produced divergent estimates of changes from childhood to adolescence. METHOD: We explored possible reasons for this discrepancy in two large, longitudinal samples of twins and singletons aged 8-17. RESULTS: There were no differences between twins and singletons in their scores on the Short Mood and Feelings Questionnaire (SMFQ), a 13-item self-report depression scale. SMFQ scores for boys fell over this age-range, while those for girls fell from age 9 to age 11 and then increased from age 12 to age 17. The mean scores of girls under 12 and those 12 and over differed by only around one-fifth of a standard deviation. However, given the non-normal distribution of the scores, a cut point that selected the upper 6% of scores created the expected female:male ratio of 2:1. CONCLUSIONS: Implications for future research on adolescent depression are discussed.     

Parathyroid hormone and calcitonin in glucose regulation

Blood glucose, insulin, calcium (Ca), phosphorus (P), parathyroid hormone (PTH) and calcitonin (CT) were evaluated in 8 normal children, aged 17–41 months, during an oral glucose load; in 7 normal children, aged 15–42 months, during i.v. glucose infusion; and in 6 normal children, aged 19–40 months, during glucagon administration. During the oral glucose tolerance tests the mean maximum decline of Ca (8.63%) and P (12.66%) was at 120 min, while PTH and CT significantly increased from basal values of 1.36 ng/ml ±0.21 and 97 pg/ml±14 to 2.20 ng/ml±0.22 and 140 pg/ml±13, respectively. During the i.v. glucose tolerance tests the mean maximum decline of Ca was 12.12% at 15 min, and that of P 15.2% at 30 min. PTH and CT levels rose significantly from basal values of 1.16 ng/ml±0.25 and 86 pg/ml±12 to 2.83 ng/ml ±0.51 and 133 pg/ml±13, respectively, at 45 min. During i.v. glucagon administration the mean maximum decline of Ca (9.64%) and P (12.28%) was at 30 min. PTH levels rose significantly from basal values of 1.2 ng/ml±0.22 to 2.1 ng/ml±0.32 at 45 min, while CT increased rapidly from basal levels of 90 pg/ml±14 to 127 pg/ml at 15 min. In conclusion, increases in glucose and insulin due to ingestion or infusion of glucose, or to glucagon injection, are therefore not only associated with a fall in serum Ca and P but also with rises in PTH and CT.     

Bioelectrical impedance for measuring percentage body fat in young persons with Down syndrome: validation with dual‐energy absorptiometry

Aim: Children with Down syndrome have an increased prevalence of obesity, although there is little work describing body composition in this population. The aims of this study were to accurately measure body fat in children with Down syndrome and to identify which existing algorithm best predicts percentage body fat in this population. Methods: Seventy children with Down syndrome had anthropometric, bioelectrical impedance analysis (BIA) and dual‐energy X‐ray absorptiometry (DXA) data collected to calculate percentage body fat (PBF). Pearson correlations were carried out to assess the relationships of various methods for measuring body fat and Bland–Altman plots to assess systematic error. Results: Mean PBF was 30.5% for girls and 22.5% for boys. A total of 38% of girls and 23% of boys were obese according to international criteria. PBF as determined by DXA correlated well with PBF by BIA in both girls and boys (r = 0.91 and 0.89, respectively, p < 0.001). Conclusion: There are high rates of obesity in children with Down syndrome. BIA can be used to accurately determine adiposity in this population. We recommend the use of the Schaeffer algorithm for calculation of PBF in children with Down syndrome.     

52例肥胖和超重儿童糖耐量及胰岛素释放试验分析

目的 了解肥胖和超重儿童糖代谢及胰岛细胞功能状况。方法 对52例单纯性肥胖与超重儿童进行口服糖耐量试验,并测定其血糖及胰岛素水平。计算胰岛素抵抗指数(IR),胰岛素敏感指数(IS),服糖后30min胰岛素增加值与血糖增加值的比值。并查甘油三酯、肝脏B超。体重指数(BMI)与IR之间、不同BMI组之间、糖耐量减低组与对照组之间进行比较。结果 发现糖尿病1例(1．9％),IGT者5例(9．6％)。IR≥2．8为胰岛素抵抗,占76．9％。BMI与IR之间无相关关系。不同BMI组之间IR、IS、服糖后30min胰岛素增加值与血糖增加值的比值差异均无统计学意义。糖耐量减低组与对照组之间IR、IS差异无统计学意义,服糖后30min胰岛素增加值与血糖增加值的比值之间差异有统计学意义。甘油三酯升高19例(37％),脂肪肝16例(53％)。结论 肥胖与超重儿童普遍存在胰岛素抵抗和敏感性下降,其与BMI程度无关。肥胖伴糖耐量减低儿童除胰岛素抵抗外存在明显的B细胞功能减退。许多肥胖和超重儿童同时存在脂代谢紊乱。     

Reduced secretion of gastric inhibitory polypeptide in turner patients with impaired glucose tolerance

There is a well documented increase in the incidence of abnormal glucose tolerance in patients with Turner syndrome. To elucidate the pathophysiology of this phenomenon, we studied the serum concentrations of gastric inhibitory polypeptide (GIP) — as probably the most important hormonal factor of the entero-insular axis — in relation to impaired glucose tolerance in this syndrome. Oral glucose tolerance tests were performed in 12 Turner patients with simultaneous determination of plasma glucose, insulin and GIP. An impaired glucose tolerance (iGT) was found in four patients with a chronological age between 12.3 and 14.9 years. These patients were compared with found Turner patients of similar age and weight and a normal glucose tolerance (nGT). The highest insulin level occurred 90 min after stimulation in the patients with iGT compared to 30 min in the nGT group. Interestingly, the total areas under the insulin curves were not different. Stimulated plasma GIP concentrations and the areas under the GIP curves wer significantly lower in iGT compared to nGT patients. A disturbed entero-insular axis might contribute to the delayed — rather than diminished — release of insulin in patients with Turner syndrome and impaired glucose tolerance.Deceased February 21, 1987