H.A. Delemarre-van de Waal

Individuals at increased coronary heart disease risk are characterized by an impaired microvascular function in skin.

Background To investigate whether microvascular function in skin is a valid model to study the relationships between cardiovascular risk factors and microvascular function, we investigated skin microvascular function in individuals with increased coronary heart disease (CHD) risk.

Infant and Childhood Growth Patterns, Insulin Sensitivity, and Blood Pressure in Prematurely Born Young Adults

OBJECTIVE. Preterm infants are at increased risk to develop insulin resistance and high blood pressure. The influence of growth during childhood is not well established. METHODS. We investigated childhood growth patterns in relation to blood pressure and insulin sensitivity, measured by the hyperinsulinemic euglycemic clamp, in young adults. We compared 29 subjects born preterm appropriate for gestational age, 28 subjects born preterm small for gestational age, and 30 subjects born at term with a normal birth weight. RESULTS. Insulin sensitivity expressed as Mi value (glucose disposal mg/kg/min (insulin levels pmol/l) × 100) was lower in infants in the POPS-AGA (18.2) and POPS-SGA (15.2) groups than in the CON group (24.7). Systolic and diastolic blood pressure (mmHg) were higher in infants in the POPS-AGA (132/72) and POPS-SGA (127/71) groups than in the CON group (118/65). The preterm-born subjects, in lowest insulin sensitivity quartile had a higher height standard deviation score at ages 1, 2, and 5 years and a higher weight SD score at ages 2, 5, 10, 19, and 21 years than did those in the lowest insulin sensitivity quartile. The infants in the highest systolic blood pressure quartile had a higher height SD score at 3 months of age and at ages 2, 5, 10, 19, and 21 years and a higher weight SD score at ages 1, 2, 5, 10, 19, and 21 years than those in the lowest systolic blood pressure quartile. CONCLUSIONS. Young adults born preterm have lower insulin sensitivity and higher blood pressure than controls. Increments in height and weight during childhood are associated with lower insulin sensitivity and higher blood pressure in adulthood.

Health-related-quality-of-life in obese adolescents is decreased and inversely related to BMI.

Aim: To compare health related quality of life (HRQoL) of obese adolescents with normal weight controls and to explore the relation between Body Mass Index (BMI) and HRQoL.

Brain Development, Intelligence and Cognitive Outcome in Children Born Small for Gestational Age

Intrauterine growth restriction (IUGR) can lead to infants being born small for gestational age (SGA). SGA is associated with increased neonatal morbidity and mortality as well as short stature, cardiovascular disease, insulin resistance, diabetes mellitus type 2, dyslipidemia and end-stage renal disease in adulthood. In addition, SGA children have decreased levels of intelligence and cognition, although the effects are mostly subtle. The overall outcome of each child is the result of a complex interaction between intrauterine and extrauterine factors. Animal and human studies show structural alterations in the brains of individuals with IUGR/SGA. The presence of growth hormone (GH) receptors in the brain implies that the brain is also a target for GH. Exogenous GH theoretically has the ability to act on the brain. This is exemplified by the effects of GH on cognition in GH-deficient adults. In SGA children, data on the effect of exogenous GH on intelligence and cognition are scant and contradictory.

Quality of life of growth hormone (GH) deficient young adults during discontinuation and restart of GH therapy

The present study evaluates the effects of one year of discontinuation and one year of growth hormone (GH) treatment on quality of life (QoL) in young adults with childhood-onset growth hormone deficiency (CO-GHD). Twenty-two subjects (14 males, 8 females; 11 isolated growth hormone deficient [IGHD], 11 multiple pituitary hormone deficient [MPHD]), aged between 15 and 22 years, on ongoing GH treatment were assessed during one year of discontinuation. Thereafter, 9 of these patients, who were found to be still GH deficient (GHD), added by 11 newly recruited GHD patients who also were not treated in the preceding year (in total 10 males and 10 females, aged between 17 and 27, 5 IGHD, 15 MPHD), restarted GH treatment for one year. During discontinuation and restart of GH treatment somatic and psychological assessments took place every 6 months. In the first 6 months of the GH discontinuation period insulin-like growth factor I (IGF-I) level significantly declined whereas no further decrease in IGF-I was seen after month 6. The number of psychological complaints and depression increased only during the first 6 months of discontinuation. Across the 12-month of discontinuation tension increased in MPHD and decreased in IGHD patients. Only in the first 6 months of GH treatment IGF-I level increased, anxiety decreased and QoL improved. Depression scores tended to decrease across the 12 month treatment period. During the 2-year discontinuation and treatment period intra-subject IGF-I level was negatively correlated with depression, fatigue, tension and anxiety and positively with vigor and memory. At the end of the treatment period all psychometric parameters were similar or even improved compared to those at the start of the discontinuation period. It is concluded that one year discontinuation of GH treatment leads to a decrease in QoL within 6 months which effect is counteracted within 6 months after restart of GH treatment.

Pubertal Development in Children Born Small for Gestational Age

UNLABELLEDnReduced fetal growth appears to be associated with precocious adrenarche, early puberty and polycystic ovary syndrome with subsequent fertility problems. We investigated pubertal development and DHEAS levels in children born small for gestational age (SGA) and children born appropriate for gestational age (AGA). Physical examination was carried out twice. Mean age (+/-SD) at the first visit: SGA group, 9.1+/-1.1 yr; AGA group, 9.0+/-1.1 yr. AT FOLLOW-UP: SGA group, 11.6+/-1.0 yr; AGA group, 11.6 +/-1.1 yr. Pubertal stages of the children were assessed. Pubic hair was recorded as a measure of androgenization. Chronological age (CA) was expressed as a percentage of the age corresponding to the pubertal stage (CA/pubertal age [PA] x 100%). Estradiol, testosterone and dehydroepiandrosterone sulfate (DHEAS) were measured in all children. FIRST VISIT: All children were prepubertal without signs of pubarche. DHEAS concentrations were higher in SGA children than in AGA children (p = 0.004).nnnFOLLOW UPnTwenty SGA children and 15 AGA children were pubertal. CA/PA x 100% was lower in SGA girls than in AGA girls (p = 0.004). Since 2.5 years earlier all girls had been prepubertal, this means a more rapid progression in the SGA girls. CA/PA x 100% was similar in SGA and AGA boys (p = 0.1). DHEAS levels tended to be higher in SGA children than in AGA children (p = 0.06). These data support that a low birth weight may have long-lasting effects on pubertal development, as observed in a more rapid progression in SGA girls. In prepubertal SGA children, an exaggerated adrenarche is observed compared to AGA children, which tended to persist through puberty.

Impact of Gestational Age and Birth Weight on Amikacin Clearance on Day 1 of Life

BACKGROUND AND OBJECTIVESnIntrauterine growth restriction (IUGR) and prematurity are associated with a low nephron endowment. It can therefore be expected that neonates who are born premature and/or after IUGR have a lower GFR. Measurement of GFR in neonates is difficult, but the clearance of amikacin has been proven to be a reliable marker. We hypothesized that amikacin clearance is lower after IUGR or premature birth as a marker of low nephron endowment.nnnDESIGN, SETTING, PARTICIPANTS, & MEASUREMENTSnAmikacin clearance was retrospectively analyzed in 161 neonates who received amikacin within the first 24 h of life. Using the MW/Pharm computer program, a population one-compartment model was calculated. The mean population pharmacokinetic parameters were individualized for each patient according to the maximum a posteriori Bayesian fitting method and provided the amikacin clearance.nnnRESULTSnOur results show that birth weight z score and gestational age are correlated with the clearance of amikacin (partial correlation coefficient 0.159, P = 0.046, and 0.396, P < 0.001, respectively), after correction for other factors.nnnCONCLUSIONSnWe conclude that renal clearance on the first day of life is lower in neonates with a lower gestational age and/or birth weight z score. This indicates that both prematurity and IUGR impair GFR on the first day of life.

Fetal Nutrition and Timing of Puberty

Over the last decade growing evidence has been documented on the relationship between intrauterine growth retardation (IUGR) and pubertal development indicating changes in timing and progression of puberty. These changes in pubertal development are part of a growing list of IUGR-related diseases, which includes type 2 diabetes mellitus, cardiovascular disease, short stature and polycystic ovary syndrome. The influence of IUGR on the mechanisms behind the onset of puberty is still elusive. In the absence of prospective studies on gonadotropin-releasing hormone pulse patterns in IUGR children, other markers of pubertal development such as age at menarche in girls and progression of puberty have been employed. We investigated pubertal development and DHEAS levels in children born small for gestational age (SGA) after third trimester growth retardation and children born appropriate for gestational age (AGA). A faster progression of puberty was found in girls but not in boys. DHEAS levels tended to be higher in SGA children than in AGA children. In animal studies using two rat models, growth and onset of puberty based on perinatal undernutrition were also investigated. In one model intrauterine growth retardation was induced by ligation of the uterine arteries (IUGR) at day 17 of gestation and in the other model postnatal food restriction (FR) was induced by increasing litter size after birth until weaning. In both models, the rats showed a persistent growth failure. Onset of puberty was defined by vaginal opening (VO) in female rats and by balanopreputial separation (BPS) in male rats. At onset of puberty IUGR and FR rats had a lower body weight compared to controls, indicating that no threshold for body weight is needed for the onset of puberty. In the IUGR female rats, the onset of puberty was delayed and in the FR female rats the onset of puberty was in time. In both IUGR and FR female rats VO and first cycle were uncoupled. In IUGR female rats, at VO, at first cycle and at the age of 6 months the ovaries showed a decline in number of follicles indicating that intrauterine malnutrition in the female rat has a permanent influence on the growth and development of follicles. In the FR female rats, at VO, the ovaries showed a normal number of follicles but an abnormal maturation pattern. At the time of first cycle and at the age of 6 months normalization in follicle growth pattern was observed. These findings suggest that postnatal undernutrition has a transient influence on follicle growth and development. In male rats, both models showed delayed onset of puberty and impaired testicular function, as shown by decreased testosterone levels. These data indicate that early malnutrition during different critical developmental time windows may result in different long-lasting effects on pubertal development in both humans and rats.

Body size in five-year-old twins: Heritability and comparison to singleton standards

The aim of this study is to examine causes of individual differences in height, weight and body mass index (BMI) in 5-year-old children registered with the Netherlands Twin Register. In addition, we examine whether the results of twin studies can be expanded to the singleton population by comparing the data from twins to Dutch reference growth data and by looking at the twins target height, which was derived from parental height. For 2996 5-year-old twin pairs, information on height and weight and on parental height was available. Univariate and bivariate genetic analyses of height and weight and univariate analyses of BMI were conducted. In order to compare the twins to the singleton population, standard deviation scores (SDS) for height, BMI and target height were calculated based on Dutch reference growth charts for the general population from 1997. Genetic influences were an important source of variation in height, weight and BMI and the main source of covariation between height and weight. Additive genetic factors accounted for 69% and 66% of the individual differences in height in boys and girls, respectively. For weight, heritability estimates were 59% in boys and 78% in girls and for BMI 34% and 74%. The influence of common environment on height was 25% and 27%, on weight 24% and 10% and on BMI 44% and 12% in boys and girls. The bivariate model showed a large overlap between the genes influencing height and weight. Genes explain 78% (in boys) and 76% (in girls) of the covariance between weight and height. At the age of 5 years, female twins were as tall as singleton children, while male twins were shorter than singletons. For both boys and girls, however, mean height SDS was 0.6 standard deviation scores below the mean target height. All twins had lower BMI than singletons. Twins grow fairly well compared to singletons, but they grow below their target height. This may be due to the above average height of twin parents.

A Controlled Trial of Methionyl Growth Hormone Therapy in Prepubertal Children with Short Stature, Subnormal Growth Rate and Normal Growth Hormone Response to Secretagogues

ABSTRACT. Thirty short and slowly growing children with normal plasma growth hormone (GH) responses to standard provocation tests were randomly assigned to either a group (n= 20) undergoing treatment with methionyl GH (somatrem), 2IU per m2 body surface s.c. daily, or a control group (n= 10). Twelve out of 18 children who completed the first year of treatment showed a height velocity increment of more than 2 cm/year. The mean (SD) growth velocity of the treatment group increased by 3.0 (1.9) cm/year over the first year, compared with ‐0.2 (0.7) cm/year in the control group. Neither parameters of endogenous GH secretion nor plasma IGF‐I levels showed a significant correlation with the growth response. Of the auxological variables studied, pre‐treatment growth velocity (r= 0.8) and the short‐term height velocity increment (r= 0.7–0.9) showed significant correlations with the growth response in the first year of treatment. Somatrem therapy was without side effects, except in one child who developed anti‐GH antibodies in combination with a poor growth response.