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1.
Nutr Res Rev ; 36(1): 60-68, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-34526164

RESUMO

The incidence of preterm birth (PTB), delivery before 37 completed weeks of gestation, is rising in most countries. Several recent small clinical trials of myo-inositol supplementation in pregnancy, which were primarily aimed at preventing gestational diabetes, have suggested an effect on reducing the incidence of PTB as a secondary outcome, highlighting the potential role of myo-inositol as a preventive agent. However, the underlying molecular mechanisms by which myo-inositol might be able to do so remain unknown; these may occur through directly influencing the onset and progress of labour, or by suppressing stimuli that trigger or promote labour. This paper presents hypotheses outlining the potential role of uteroplacental myo-inositol in human parturition and explains possible underlying molecular mechanisms by which myo-inositol might modulate the uteroplacental environment and inhibit preterm labour onset. We suggest that a physiological decline in uteroplacental inositol levels to a critical threshold with advancing gestation, in concert with an increasingly pro-inflammatory uteroplacental environment, permits spontaneous membrane rupture and labour onset. A higher uteroplacental inositol level, potentially promoted by maternal myo-inositol supplementation, might affect lipid metabolism, eicosanoid production and secretion of pro-inflammatory chemocytokines that overall dampen the pro-labour uteroplacental environment responsible for labour onset and progress, thus reducing the risk of PTB. Understanding how and when inositol may act to reduce PTB risk would facilitate the design of future clinical trials of maternal myo-inositol supplementation and definitively address the efficacy of myo-inositol prophylaxis against PTB.


Assuntos
Diabetes Gestacional , Ruptura Prematura de Membranas Fetais , Nascimento Prematuro , Gravidez , Feminino , Recém-Nascido , Humanos , Nascimento Prematuro/prevenção & controle , Nascimento Prematuro/tratamento farmacológico , Nascimento Prematuro/epidemiologia , Inositol/farmacologia , Inositol/uso terapêutico , Diabetes Gestacional/tratamento farmacológico , Diabetes Gestacional/prevenção & controle , Ruptura Prematura de Membranas Fetais/tratamento farmacológico
2.
Int J Obes (Lond) ; 41(12): 1755-1760, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28775375

RESUMO

BACKGROUND: Vitamin D insufficiency (defined as <75 nmol l-1) is widespread among pregnant women around the world and has been proposed to influence offspring outcomes in childhood and into adult life, including adiposity and allergy. Disorders, including asthma and eczema, are on the rise among children. Our aim was to investigate the relationship between maternal 25-hydroxyvitamin D status in pregnancy and offspring adiposity, asthma and eczema in childhood. SUBJECTS AND METHODS: Maternal 25-hydroxyvitamin D concentrations were analysed in serum samples collected at 15 weeks' gestation from 1710 participants of the prospective Screening for Pregnancy Endpoints cohort study. The offspring of 1208 mothers were followed up at age 5-6 years. Data collected included height, weight, percentage body fat (PBF, measured by bioimpedance) and history of asthma and eczema. Multivariable analysis controlled for maternal body mass index (BMI), age and sex of the child and season of serum sampling. RESULTS: Complete data were available for 922 mother-child pairs. Each 10 nmol l-1 increase in maternal 25-hydroxyvitamin D concentration at 15 weeks' gestation was associated with a decrease in offspring PBF of 0.2% (95% confidence interval 0.04-0.36%, P=0.01) after adjustment for confounders but was not related to child BMI z-score. Maternal mean (±s.d.) 25-hydroxyvitamin D concentration was similar in children who did and did not have asthma (71.7±26.1 vs 73.3±27.1 nmol l-1, P=0.5), severe asthma (68.6±28.6 vs 73.3±26.8 nmol l-1, P=0.2) and eczema (71.9±27.0 vs 73.2±27.0 nmol l-1, P=0.5). CONCLUSIONS: The finding of a relationship between maternal vitamin D status and adiposity in childhood is important, particularly because vitamin D insufficiency in pregnancy is highly prevalent. The association between maternal vitamin D supplementation in pregnancy and adiposity in the offspring merits examination in randomised controlled trials.


Assuntos
Asma/etiologia , Eczema/etiologia , Mães , Obesidade Infantil/etiologia , Deficiência de Vitamina D/complicações , Vitamina D/análogos & derivados , Adiposidade , Adulto , Asma/sangue , Asma/epidemiologia , Pré-Escolar , Eczema/sangue , Eczema/epidemiologia , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Fenômenos Fisiológicos da Nutrição Materna , Inquéritos Nutricionais , Obesidade Infantil/sangue , Obesidade Infantil/epidemiologia , Gravidez , Estudos Prospectivos , Inquéritos e Questionários , Suécia/epidemiologia , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/epidemiologia
3.
BJOG ; 123(4): 588-97, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26542419

RESUMO

OBJECTIVE: To assess whether antenatal exercise in overweight/obese women would improve maternal and perinatal outcomes. DESIGN: Two-arm parallel randomised controlled trial. SETTING: Home-based intervention in Auckland, New Zealand. POPULATION AND SAMPLE: Pregnant women with body mass index ≥25 kg/m(2) . METHODS: Participants were randomised to a 16-week moderate-intensity stationary cycling programme from 20 weeks of gestation, or to a control group with no exercise intervention. MAIN OUTCOME MEASURES: Primary outcome was offspring birthweight. Perinatal and maternal outcomes were assessed, with the latter including weight gain, aerobic fitness, quality of life, pregnancy outcomes, and postnatal body composition. Exercise compliance was recorded with heart rate monitors. RESULTS: Seventy-five participants were randomised in the study (intervention 38, control 37). Offspring birthweight (adjusted mean difference 104 g; P = 0.35) and perinatal outcomes were similar between groups. Aerobic fitness improved in the intervention group compared with controls (48.0-second improvement in test time to target heart rate; P = 0.019). There was no difference in weight gain, quality of life, pregnancy outcomes or postnatal maternal body composition between groups. However, compliance with exercise protocol was poor, with an average of 33% of exercise sessions completed. Sensitivity analyses showed that greater compliance was associated with improved fitness (increased test time (P = 0.002), greater VO2 peak (P = 0.015), and lower resting heart rate (P = 0.014)), reduced postnatal adiposity (reduced fat mass (P = 0.007) and body mass index (P = 0.035)) and better physical quality of life (P = 0.034). CONCLUSIONS: Maternal non-weight-bearing moderate-intensity exercise in pregnancy improved fitness but did not affect birthweight or clinical outcomes. TWEETABLE ABSTRACT: Moderate-intensity exercise in overweight/obese pregnant women improved fitness but had no clinical effects.


Assuntos
Terapia por Exercício , Obesidade/terapia , Sobrepeso/terapia , Gestantes , Cuidado Pré-Natal , Adulto , Índice de Massa Corporal , Feminino , Humanos , Nova Zelândia/epidemiologia , Obesidade/epidemiologia , Obesidade/prevenção & controle , Sobrepeso/epidemiologia , Sobrepeso/prevenção & controle , Cooperação do Paciente , Gravidez , Resultado da Gravidez , Gestantes/psicologia , Qualidade de Vida , Comportamento de Redução do Risco , Resultado do Tratamento , Aumento de Peso
4.
J Obstet Gynaecol ; 36(1): 1-2, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-25692217

RESUMO

We assessed whether maternal height was associated with gestational age in a cohort of 294 children born at term. Increasing maternal height was associated with longer pregnancy duration (p = 0.002). Stratified analyses showed that the main effect on pregnancy length appears to occur among shorter mothers (<165 cm tall), whose pregnancies were ∼0.6 and ∼0.7 weeks shorter than pregnancies of mothers 165-170 cm (p = 0.0009) and >170 cm (p = 0.0002) tall, respectively. Further, children of shorter mothers were more likely to be born early term than those of average height (p = 0.021) and taller (p = 0.0003) mothers. Maternal stature is likely to be a contributing factor influencing long-term outcomes in the offspring via its effect on pregnancy length.


Assuntos
Estatura , Idade Gestacional , Gravidez , Feminino , Humanos , Recém-Nascido , Masculino , Nascimento a Termo , Fatores de Tempo
5.
Clin Endocrinol (Oxf) ; 83(1): 85-90, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25523467

RESUMO

OBJECTIVE: Treatment of growth hormone (GH)-deficient adults with GH has been shown to improve a range of metabolic abnormalities and enhance quality of life. However, the results of access to nationally funded treatment have not been reported. DESIGN: Retrospective case series auditing nationally funded treatment of defined GH-deficient adults in New Zealand, with carefully designed entry and exit criteria overseen by a panel of endocrinologists. PATIENTS: Applications for 201 patients were assessed and 191 approved for funded treatment over the initial 3 years since inception. The majority had GH deficiency following treatment of pituitary adenomas or tumours adjacent to the pituitary. RESULTS: After an initial 9-month treatment period using serum IGF-I measurements to adjust GH dosing, all patients reported a significant improvement in quality of life (QoL) score on the QoL-AGHDA(®) instrument (baseline (95%CI) 19 (18-21), 9 months 6 (5-7.5)), and mean serum IGF-I SD scores rose from -3 to zero. Mean waist circumference decreased significantly by 2.8 ± 0.6 cm. The mean maintenance GH dose after 9 months of treatment was 0.39 mg/day. After 3 years, 17% of patients had stopped treatment, and all of the remaining patients maintained the improvements seen at 9 months of treatment. CONCLUSION: Carefully designed access to nationally funded GH replacement in GH-deficient adults was associated with a significant improvement in quality of life over a 3-year period with mean daily GH doses lower than in the majority of previously reported studies.


Assuntos
Custos de Medicamentos , Financiamento Governamental , Terapia de Reposição Hormonal/métodos , Hormônio do Crescimento Humano/uso terapêutico , Hipopituitarismo/tratamento farmacológico , Adolescente , Adulto , Idoso , Estudos de Coortes , Definição da Elegibilidade , Feminino , Terapia de Reposição Hormonal/economia , Hormônio do Crescimento Humano/deficiência , Hormônio do Crescimento Humano/economia , Humanos , Hipopituitarismo/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Pessoa de Meia-Idade , Nova Zelândia , Qualidade de Vida , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
6.
Hum Reprod ; 29(11): 2583-91, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25217609

RESUMO

STUDY QUESTION: Are childhood measures of phenotype associated with peri-conception parental, IVF treatment and/or embryonic characteristics of IVF children? SUMMARY ANSWER: Birthweight, childhood body mass index (BMI) and height of pre-pubertal IVF children were strongly associated with peri-conception factors, including follicular and embryonic characteristics. WHAT IS KNOWN ALREADY: A growing number of studies have identified a range of phenotypic differences between IVF and naturally conceived pre-pubertal children; for example, birthweights are lower following a fresh compared with a thawed embryo transfer. STUDY DESIGN, SIZE, DURATION: This retrospective cohort study included IVF children (n = 96) born at term (>37 weeks) after a singleton pregnancy from the transfer of either fresh or thawed embryos in New Zealand. Between March 2004 and November 2008, these children were subjected to clinical assessment before puberty. PARTICIPANTS/MATERIALS, SETTING, METHODS: Clinical assessment provided anthropometric measures of children aged 3.5-11 years old. Peri-conception factors (n = 36) derived retrospectively from parental, treatment, laboratory and embryonic variables (n = 69) were analysed using multiple stepwise regression with respect to standard deviation scores (SDSs) of the birthweight, mid-parental corrected BMI and height of the IVF children. Data from children conceived from fresh (n = 60) or thawed (n = 36) embryos, that met inclusion criteria and had high-quality data with >90% completeness, were analysed. MAIN RESULTS AND THE ROLE OF CHANCE: Embryo treatment at transfer was identified as a predictor of birthweight with thawed embryos resulting in heavier birthweights than fresh embryos [P = 0.02, 95% confidence interval (CI) fresh minus thawed: -1.047 to -0.006]. Birthweight SDS was positively associated with mid-parental corrected BMI SDS (P = 0.003, slope 0.339 ± 0.100). Four factors were related (P < 0.05) to mid-parental corrected height SDS. In particular, child height was inversely associated with the diameter of lead follicles at oocyte retrieval (P < 0.0001, slope -0.144 ± 0.040) and with the quality score of embryos at transfer (P = 0.0008, slope -0.425 ± 0.157), and directly associated with the number of follicles retrieved (P = 0.05, slope 1.011 ± 0.497). Child height was also positively associated with the transfer of a fresh as opposed to thawed embryo (P < 0.001, 95% CI 0.275-0.750). LIMITATIONS, REASONS FOR CAUTION: More than one embryo was transferred in most cycles so mean development and quality data were used. The large number of variables measured was on a relatively small sample size. Large cohorts from multiple clinics using a variety of treatment protocols and embryology methods are needed to confirm the associations identified and ultimately to test these factors as possible predictors of phenotype. WIDER IMPLICATIONS OF THE FINDINGS: This is the first study to directly associate peri-conception measures of IVF treatment with a pre-pubertal child's phenotype. Demonstration that peri-conception measures relate to a pre-pubertal child's phenotype extends the range of factors that may influence growth and development. These findings, if corroborated by larger studies, would provide invaluable information for practitioners, who may want to consider the impact of ovarian stimulation protocols as well as the quality of the embryo transferred on a child's growth and development, in addition to their impact on pregnancy rate. STUDY FUNDING/COMPETING INTERESTS: This work was supported by grants from the National Research Centre of Growth and Development New Zealand (grant 3682065) and the Australasian Paediatric Endocrine Group (APEG; grant 3621994), as well as a fellowship from Fertility Associates New Zealand awarded to M.P.G. In terms of competing interest, J.C.P is a shareholder of Fertility Associates. M.P.G. currently holds the position of Merck Serono Lecturer in Reproductive Biology. W.S.C. and P.L.H. have also received grants and non-financial support from Novo Nordisk, as well as personal fees from Pfizer that are unrelated to the current study. The other authors have no conflict of interest to declare.


Assuntos
Peso ao Nascer/fisiologia , Desenvolvimento Infantil/fisiologia , Transferência Embrionária/métodos , Fertilização in vitro/métodos , Folículo Ovariano/fisiologia , Fenótipo , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Masculino , Indução da Ovulação/métodos , Gravidez , Estudos Retrospectivos
7.
Sci Rep ; 12(1): 1276, 2022 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-35075183

RESUMO

The infant gut microbiome contains a portion of bacteria that originate from the maternal gut. In the infant gut these bacteria encounter a new metabolic environment that differs from the adult gut, consequently requiring adjustments in their activities. We used pilot community RNA sequencing data (metatranscriptomes) from ten mother-infant dyads participating in the NiPPeR Study to characterize bacterial gene expression shifts following mother-to-infant transmission. Maternally-derived bacterial strains exhibited large scale gene expression shifts following the transmission to the infant gut, with 12,564 activated and 14,844 deactivated gene families. The implicated genes were most numerous and the magnitude shifts greatest in Bacteroides spp. This pilot study demonstrates environment-dependent, strain-specific shifts in gut bacteria function and underscores the importance of metatranscriptomic analysis in microbiome studies.


Assuntos
Microbioma Gastrointestinal , Lactente , Metagenoma , Mães , Transcriptoma , Feminino , Humanos , Projetos Piloto
8.
J Dev Orig Health Dis ; 10(5): 529-535, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30813979

RESUMO

We assessed whether paternal demographic, anthropometric and clinical factors influence the risk of an infant being born large-for-gestational-age (LGA). We examined the data on 3659 fathers of term offspring (including 662 LGA infants) born to primiparous women from Screening for Pregnancy Endpoints (SCOPE). LGA was defined as birth weight >90th centile as per INTERGROWTH 21st standards, with reference group being infants ⩽90th centile. Associations between paternal factors and likelihood of an LGA infant were examined using univariable and multivariable models. Men who fathered LGA babies were 180 g heavier at birth (P<0.001) and were more likely to have been born macrosomic (P<0.001) than those whose infants were not LGA. Fathers of LGA infants were 2.1 cm taller (P<0.001), 2.8 kg heavier (P<0.001) and had similar body mass index (BMI). In multivariable models, increasing paternal birth weight and height were independently associated with greater odds of having an LGA infant, irrespective of maternal factors. One unit increase in paternal BMI was associated with 2.9% greater odds of having an LGA boy but not girl; however, this association disappeared after adjustment for maternal BMI. There were no associations between paternal demographic factors or clinical history and infant LGA. In conclusion, fathers who were heavier at birth and were taller were more likely to have an LGA infant, but maternal BMI had a dominant influence on LGA.


Assuntos
Peso ao Nascer , Índice de Massa Corporal , Pai/estatística & dados numéricos , Macrossomia Fetal/epidemiologia , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Adulto , Austrália/epidemiologia , Feminino , Idade Gestacional , Humanos , Incidência , Lactente , Recém-Nascido , Irlanda/epidemiologia , Masculino , Gravidez , Estudos Prospectivos , Fatores de Risco , Reino Unido/epidemiologia
9.
Pediatr Obes ; 13(12): 766-777, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29271074

RESUMO

BACKGROUND: Prevalence of childhood obesity is high in developed countries, and there is a growing concern regarding increasing socio-economic disparities. OBJECTIVES: To assess trends in the prevalence of overweight, obesity and extreme obesity among New Zealand 4-year olds, and whether these differ by socio-economic and ethnic groupings. METHODS: A national screening programme, the B4 School Check, collected height and weight data for 75-92% of New Zealand 4-year-old children (n = 317 298) between July 2010 and June 2016. Children at, or above, the 85th, 95th and 99.7th percentile for age and sex adjusted body mass index (according to World Health Organization standards) were classified as overweight, obese and extremely obese, respectively. Prevalence rates across 6 years (2010/11 to 2015/16) were examined by sex, across quintiles of socio-economic deprivation, and by ethnicity. RESULTS: The prevalence of overweight, obesity and extreme obesity decreased by 2.2 [95% CI, 1.8-2.5], 2.0 [1.8-2.2] and 0.6 [0.4-0.6] percentage points, respectively, between 2010/2011 and 2015/2016. The downward trends in overweight, obesity and extreme obesity in the population persisted after adjustment for sex, ethnicity, deprivation and urban/rural residence. Downward trends were also observed across sex, ethnicity and deprivation groups. CONCLUSIONS: The prevalence of obesity appears to be declining in 4-year-old children in New Zealand across all socio-economic and ethnic groups.


Assuntos
Obesidade Infantil/epidemiologia , Antropometria/métodos , Pré-Escolar , Etnicidade , Feminino , Humanos , Masculino , Nova Zelândia/epidemiologia , Prevalência , Fatores Socioeconômicos
11.
Endocrinology ; 146(10): 4211-6, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16020474

RESUMO

An adverse prenatal environment may induce long-term metabolic consequences, in particular obesity and insulin resistance. Although the mechanisms are unclear, this programming has generally been considered an irreversible change in developmental trajectory. Adult offspring of rats subjected to undernutrition during pregnancy develop obesity, hyperinsulinemia, and hyperleptinemia, especially in the presence of a high-fat diet. Reduced locomotor activity and hyperphagia contribute to the increased fat mass. Using this model of maternal undernutrition, we investigated the effects of neonatal leptin treatment on the metabolic phenotype of adult female offspring. Leptin treatment (rec-rat leptin, 2.5 microg/g.d, sc) from postnatal d 3-13 resulted in a transient slowing of neonatal weight gain, particularly in programmed offspring, and normalized caloric intake, locomotor activity, body weight, fat mass, and fasting plasma glucose, insulin, and leptin concentrations in programmed offspring in adult life in contrast to saline-treated offspring of undernourished mothers who developed all these features on a high-fat diet. Neonatal leptin had no demonstrable effects on the adult offspring of normally fed mothers. This study suggests that developmental metabolic programming is potentially reversible by an intervention late in the phase of developmental plasticity. The complete normalization of the programmed phenotype by neonatal leptin treatment implies that leptin has effects that reverse the prenatal adaptations resulting from relative fetal undernutrition.


Assuntos
Envelhecimento/fisiologia , Leptina/farmacologia , Obesidade/etiologia , Absorciometria de Fóton , Tecido Adiposo/anatomia & histologia , Tecido Adiposo/crescimento & desenvolvimento , Envelhecimento/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Feminino , Insulina/sangue , Desnutrição/fisiopatologia , Obesidade/prevenção & controle , Gravidez , Complicações na Gravidez/fisiopatologia , Efeitos Tardios da Exposição Pré-Natal , Ratos , Ratos Wistar , Aumento de Peso/efeitos dos fármacos
12.
J Clin Endocrinol Metab ; 74(4): 934-8, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1548360

RESUMO

Two distinct GH-binding proteins (GHBP) are present in circulation in the human. The major GHBP (high affinity GHBP) is homologous to the extracellular portion of the GH receptor and the concentration of this protein in circulation may reflect the status of the GH receptor in the tissues. To gain information about the concentration of GHBPs in children with insulin-dependent diabetes mellitus (IDDM), we measured GHBP in the serum of 46 children with IDDM and compared it to that in 53 healthy control subjects matched for age and sexual maturity. The total GHBP concentration in the group of pubertal and postpubertal IDDM patients was lower than that measured in the control group (mean +/- SEM: 7.8 +/- 0.4 vs. 9.0 +/- 0.5%, P = 0.05). The diabetic children in stages II to IV of puberty had a lower GHBP level compared to their healthy controls (7.6 +/- 0.4 vs. 9.1 +/- 0.5%, P = 0.02), whereas the difference between the diabetic and control group of postpubertal children was not statistically different (8.3 +/- 0.7 vs. 9.7 +/- 0.7%, P = 0.1). In a randomly selected subset of eight patients and eight controls, the concentration of the individual GHBPs (i.e. high affinity and low affinity (GHBP) was estimated by gel chromatography. There was no difference in the low affinity GHBP between the two groups (9.9 +/- 0.6% vs. 9.9 +/- 0.4%), but the high affinity GHBP was less in the diabetic group than in the control group (10.5 +/- 0.9 vs. 15.6 +/- 1.0%, P less than 0.01). In the diabetic group, there was no correlation between the GHBP levels and age, duration of diabetes, hemoglobin A1, or insulin dose. We conclude that in IDDM there is less of the high affinity GHBP, suggesting a decrease in the number of GH receptors in these patients. This decrease may contribute to GH resistance manifesting as decreased insulin-like growth factor-I levels despite high GH levels in patients with IDDM.


Assuntos
Proteínas de Transporte/sangue , Diabetes Mellitus Tipo 1/sangue , Adolescente , Adulto , Criança , Cromatografia em Gel , Feminino , Humanos , Masculino , Puberdade/sangue
13.
J Clin Endocrinol Metab ; 70(6): 1644-50, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2189887

RESUMO

The modified minimal model (MMM), a recently introduced method that assesses insulin sensitivity (SI) by a computed mathematical analysis of the relation between the change in insulin and glucose clearance after a bolus of iv glucose, followed 20 min later by a bolus of tolbutamide, has been standardized in adults, but this method has not been validated in children. We performed an abbreviated 90-min MMM test in 50 children who were siblings of patients with insulin-dependent diabetes mellitus and 7 healthy adult volunteers and compared the results to the standard 180-min MMM test in 11 of these subjects. The cohort consisted of 29 prepubertal children [16 males and 13 females; 8.7 +/- 2.0 (mean +/- SEM) yr old]; 16 pubertal children defined as less than 17 yr of age and Tanner stage 2-5 (8 males and 8 females; 13.4 +/- 1.8 yr old), and 12 postpubertal subjects (7 males and 5 females; 18.2 +/- 0.9 yr old), with no significant difference in the weight for length index (WLI) among the 3 groups and with sera of all subjects negative for islet cell antibodies and insulin autoantibodies. The test procedure consisted of 3 baseline blood samples over 30 min, followed at zero time by 0.3 g/kg 25% dextrose infused iv over 1 min and an iv injection of tolbutamide (5 mg/kg) 20 min later; sequential blood samples for glucose and insulin measurements were withdrawn from zero time until completion 90 or 180 min later. In the 11 subjects who underwent both the standard and the abbreviated tests, there was no significant difference between the SI estimated by the 2 methods provided that glucose and insulin values were interpolated at 180 min during the computer calculations of the abbreviated test. Using the 90-min abbreviated test, the SI of the pubertal subjects (2.92 +/- 0.45) was markedly less than that of the prepubertal subjects (6.57 +/- 0.45; P = 0.0001). While the postpubertal group value of 4.63 +/- 0.86 was significantly higher than that of the pubertal group (P = 0.0001), the pre- and postpubertal groups remained significantly different (P = 0.0001). The 10 obese subjects with WLI greater than 120% had a lower SI (3.5 +/- 0.53) than the 47 nonobese subjects with WLI less than 120% (SI = 5.48 +/- 0.42; P less than 0.04), and there was a negative correlation between SI and WLI. None of the study subjects experienced symptomatic hypoglycemia during the test.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Glicemia/metabolismo , Teste de Tolerância a Glucose/métodos , Insulina/sangue , Obesidade/metabolismo , Puberdade/metabolismo , Adolescente , Adulto , Criança , Pré-Escolar , Simulação por Computador , Feminino , Humanos , Masculino , Análise de Regressão
14.
J Clin Endocrinol Metab ; 85(11): 4212-8, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11095456

RESUMO

It has become common practice to apply GH treatment in short Turner syndrome patients with the objective of promoting growth. The variability in response and the high costs of this treatment demand the individualization and optimization of therapy. Based on 686 prepubertal Turner patients from the Kabi International Growth Study (KIGS; Pharmacia & Upjohn, Inc. International Growth Database), we undertook a multiple regression analysis of height velocity (centimeters per yr) by using various parameters of potential relevance. Derived prediction models for the first 4 yr of GH treatment were validated with 76 additional KIGS patients and 81 patients from Tuebingen, Germany. Among the 6 predictors identified, the most influential variable for first year growth response was the natural log (ln) of the weekly GH dose. The first year growth response was also correlated with age and distance between height and target height (SD score; both negative) and body weight SD, number of GH injections per week, and oxandrolone treatment given additionally (positive). The first year model explains 46% of the variability, with 1 SD of 1.26 cm. For the second to fourth years, 5 predictors were identified: height velocity during previous years, weekly GH dose (ln), weight SD, oxandrolone therapy (all positive), and age (negative). These models explained 32%, 29%, and 30% of the variability, respectively, with SD scores of 1.1, 1.0, and 1.0 cm, respectively. When the models were applied to the other cohorts, no significant difference was noted between observed and predicted responses. Although the parameters used in our models do not entirely explain the variability in the growth response in Turner syndrome, the parameters themselves were clinically relevant to our present understanding and proved to be of high precision. Some of the tested markers, such as karyotype, do not contribute to the growth response. These variables make the models practical and suitable for planning beneficial and cost-effective therapy.


Assuntos
Estatura , Crescimento , Hormônio do Crescimento Humano/uso terapêutico , Modelos Estatísticos , Síndrome de Turner/tratamento farmacológico , Síndrome de Turner/fisiopatologia , Anabolizantes/uso terapêutico , Criança , Estudos de Coortes , Bases de Dados como Assunto , Feminino , Humanos , Matemática , Oxandrolona/uso terapêutico , Valor Preditivo dos Testes , Valores de Referência , Análise de Regressão , Reprodutibilidade dos Testes
15.
J Clin Endocrinol Metab ; 82(2): 402-6, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9024226

RESUMO

Epidemiological studies have demonstrated an association between intrauterine growth retardation and an increased risk of adult diseases that include essential hypertension, noninsulin-dependent diabetes mellitus, and ischemic heart disease. A common feature of these diseases is insulin resistance. To investigate whether abnormal insulin sensitivity was a characteristic of subjects with intrauterine growth retardation (IUGR), we compared two groups of short prepubertal children: a group with IUGR (birth weight less than the tenth percentile; n = 15) and a normal birth weight group (n = 12). Subjects underwent a modified frequently sampled iv glucose tolerance test that permitted calculation of the acute insulin response, insulin sensitivity index, and glucose effectiveness. A marked difference in the insulin sensitivity index was noted between groups, with the IUGR group being less insulin sensitive [6.9 vs. 16.9 10(-4)min-1.(microU/mL); P = 0.0048]. The acute insulin response was also significantly different between groups, with IUGR subjects having higher insulin levels (445 vs. 174 microU/mL; P = 0.005). There was no difference in glucose effectiveness between groups. Short prepubertal IUGR children have a specific impairment in insulin sensitivity compared to their normal birth weight peers. In short IUGR children, impaired insulin sensitivity is a potential marker for the early identification and intervention in the development of late adult-onset noninsulin-dependent diabetes mellitus.


Assuntos
Estatura , Retardo do Crescimento Fetal/patologia , Retardo do Crescimento Fetal/fisiopatologia , Resistência à Insulina , Peso ao Nascer , Glicemia/metabolismo , Criança , Pré-Escolar , Feminino , Intolerância à Glucose , Humanos , Masculino , Valores de Referência
16.
J Clin Endocrinol Metab ; 84(4): 1174-83, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10199749

RESUMO

Postmarketing surveillance studies of recombinant human GH therapy, such as the Kabi Pharmacia International Growth Study (KIGS; Pharmacia & Upjohn, Inc., International Growth Database), have accumulated extensive data concerning the characteristics and growth outcomes of children with various causes of short stature. These data provide an opportunity to analyze the factors that determine responsiveness to GH and allow the development of disease-specific growth prediction models. We undertook a multiple regression analysis of height velocity (centimeter per yr) with various patient parameters of potential relevance using data from a cohort of 593 prepubertal children with idiopathic GH deficiency (GHD) from the KIGS database. Our aim was to produce models that would have practical utility for predicting prepubertal growth during each of the first 4 yr of GH replacement therapy. These models were validated by a prospective comparison of predicted and observed growth outcomes in an additional 3 cohorts of prepubertal children with idiopathic GHD: 237 additional KIGS patients, 29 patients from the Australian OZGROW study, and 33 patients from Tubingen, Germany. The most influential variable for first year growth response was the natural log (ln) of the maximum GH response during provocation testing, which was inversely correlated with height velocity. The first year growth response was also inversely correlated with chronological age and height SD score minus midparental height SD score. First year growth was positively correlated with body weight SD score, weekly GH dose (ln), and birth weight SD score. Two first year models were developed using these parameters, 1 including and 1 excluding the maximum GH response to provocative testing. The former model explained 61% of the response variability, with a SD of 1.46 cm; the latter model explained 45% of the variability, with a SD of 1.72 cm. The two models gave similar predictions, although the model excluding the maximum GH response to testing tended to underpredict the growth response in patients with very low GH secretory capacity. For the second, third, and fourth year growth responses, 4 predictors were identified: height velocity during the previous year (positively correlated), body weight SD score (positively correlated), chronological age (negatively correlated), and weekly GH dose (ln; positively correlated). The models for the second, third, and fourth year responses explained 40%, 37%, and 30% of the variability, respectively, with SDs of 1.19, 1.05, and 0.95 cm, respectively. When the models were applied prospectively to the other cohorts, there were no significant differences between observed and predicted responses in any of the cohorts in any year of treatment. The fourth year response model gave accurate prospective growth predictions for the fifth to the eighth prepubertal years of GH treatment in a subset of 48 KIGS patients. Analyses of Studentized residuals provided further validation of the models. The parameters used in our models do not explain all of the variability in growth response, but they have a high degree of precision (low error SDs). Moreover, the parameters used are robust and easily accessible. These properties give the models' practical utility as growth prediction tools. The availability of longitudinal, disease-specific models will be helpful in the future for enabling growth-promoting therapy to be planned at the outset, optimized for efficacy and economy, and individualized to meet treatment goals based on realistic expectations.


Assuntos
Hormônio do Crescimento/uso terapêutico , Crescimento/efeitos dos fármacos , Terapia de Reposição Hormonal , Hormônio do Crescimento Humano/deficiência , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Matemática , Modelos Biológicos , Análise de Regressão
17.
Growth Horm IGF Res ; 14 Suppl A: S136-9, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15135796

RESUMO

An association between low birth weight, commonly a reflection of an adverse in utero environment, and the subsequent development of diseases such as type 2 diabetes and hypertension in later life is now generally accepted - as is an association between an adverse perinatal environment and a permanent reduction in insulin sensitivity. This and other metabolic abnormalities have been demonstrated from childhood through to adulthood in subjects who were born full-term but small for gestational age (SGA). Less is known about children born prematurely into an adverse neonatal environment. We present data demonstrating that premature infants also have metabolic abnormalities similar to those observed in full-term, SGA children, and that these occur irrespective of whether the premature infants are SGA or appropriate for gestational age (AGA).


Assuntos
Recém-Nascido Prematuro , Recém-Nascido Pequeno para a Idade Gestacional , Resistência à Insulina , Criança , Seguimentos , Humanos , Recém-Nascido , Modelos Biológicos
18.
J Pediatr Endocrinol Metab ; 10(1): 27-33, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9364339

RESUMO

In Turner's syndrome there is marked heterogeneity of growth response to growth hormone (GH) therapy. The study aim was to identify pretreatment factors that influence response to GH therapy. The 70 subjects recruited were prepubertal, had not received sex steroids and had received 28 units/m2/week of GH for > or = 1 year. Pretreatment variables associated with the greatest improvement in height SDS (r2 = 0.58) were weight for length index (p = 0.0001), target height (p = 0.004), bone age delay (p = 0.008) and age (p = 0.04). In conclusion, during two years of GH therapy the best growth response occurred in girls who were younger, heavier, had a delayed bone age and tall parents. Height SDS as a continuous variable is the most effective measure of growth when considering pretreatment factors that may influence response to GH therapy.


Assuntos
Hormônio do Crescimento Humano/uso terapêutico , Síndrome de Turner/tratamento farmacológico , Adolescente , Determinação da Idade pelo Esqueleto , Fatores Etários , Estatura , Peso Corporal , Criança , Feminino , Crescimento , Hormônio do Crescimento Humano/administração & dosagem , Humanos
19.
Acta Paediatr Suppl ; 88(428): 72-5, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10102057

RESUMO

Final height was evaluated in 369 patients with idiopathic growth hormone deficiency (IGHD) enrolled in KIGS--the Pharmacia & Upjohn International Growth Database. At the start of growth hormone (GH) therapy, the patients were 9.8 years of age, their mid-parental height SDS was -0.8, and their height SDS was -3.1. Of the 369 patients, 50% had multiple hormone deficiencies, and puberty was induced in 31%. Patients were 18 years of age at completion of GH therapy, and had received GH at a dose of 0.49 IU/kg/week (0.16 mg/kg/week), with a mean of 5.2 injections/week for 8.1 years. Final height SDS was -1.5, final minus initial height SDS was 1.7 and final minus mid-parental height SDS was -0.5. A Swedish subgroup (n = 69) received conventional GH therapy throughout at 0.65 IU/kg/week (0.22 mg/kg/week), with seven injections/week for a mean of 9.4 years. These patients achieved their genetic potential (final minus mid-parental height SDS, 0.03), with a normal final height SDS of -0.3. For the total group, the following variables were associated with final height: mid-parental height SDS (r = 0.62), injection frequency (r = 0.37), duration of GH treatment (r = 0.28), peak stimulated GH concentration (r = -0.25), age (r = -0.19) (all p < 0.001) and height velocity SDS in the first year of treatment (r = 0.20, p = 0.004). In conclusion, genetic potential, expressed as the mid-parental height, is the variable with the greatest identified influence on final height during GH treatment in IGHD. Current GH regimens will lead to a normal height and attainment of mid-parental height. However, higher dose, individualized GH regimens are likely to be necessary for patients with IGHD who are disadvantaged at the time of commencing GH therapy, such as those with short parents, those whose treatment began in late childhood or adolescence and those with less severe GHD.


Assuntos
Estatura/efeitos dos fármacos , Transtornos do Crescimento/tratamento farmacológico , Hormônio do Crescimento Humano/uso terapêutico , Adolescente , Adulto , Criança , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Seguimentos , Alemanha , Transtornos do Crescimento/etiologia , Hormônio do Crescimento Humano/deficiência , Humanos , Injeções Intramusculares , Masculino , Análise Multivariada , Análise de Regressão , Suécia , Resultado do Tratamento
20.
Acta Paediatr Suppl ; 88(433): 122-5, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10626562

RESUMO

A mathematical model for predicting the growth response in patients with Turner syndrome who received growth hormone (GH) therapy was developed by analysing data from KIGS, the Pharmacia & Upjohn International Growth Database. A model for year 1 of GH therapy explained 46% of the variability of the growth response, with GH dose being the most important of the predictors of height velocity. In years 2-4 of therapy, height velocity during the previous year was the most important predictor, suggesting that an individual's initial response to GH may determine the height outcome of treatment. Additional predictors of height velocity in years 1-4 of GH therapy included age (negative), weight SDS and additional treatment with oxandrolone. The predictions in all 4 years were highly accurate, as indicated by the low error SDs. However, relatively low predictive power (R) during years 2-4 of treatment suggests the models are missing other parameters that would explain more of the variability of the growth response. These growth prediction models could help clinicians to design individualized treatment regimens, provide realistic expectations of therapy outcomes, and adjust treatment on the basis of detected differences between observed and predicted height velocities.


Assuntos
Estatura , Hormônio do Crescimento Humano/uso terapêutico , Síndrome de Turner/tratamento farmacológico , Estatura/efeitos dos fármacos , Criança , Feminino , Humanos , Modelos Lineares , Resultado do Tratamento
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