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Growth hormone (GH) has been used for over 35 years, and its safety and efficacy has been studied extensively. Experimental studies showing the permissive role of GH/insulin-like growth factor 1 (IGF-I) in carcinogenesis have raised concerns regarding the safety of GH replacement in children and adults who have received treatment for cancer and those with intracranial and pituitary tumours. A consensus statement was produced to guide decision-making on GH replacement in children and adult survivors of cancer, in those treated for intracranial and pituitary tumours and in patients with increased cancer risk. With the support of the European Society of Endocrinology, the Growth Hormone Research Society convened a Workshop, where 55 international key opinion leaders representing 10 professional societies were invited to participate. This consensus statement utilized: (1) a critical review paper produced before the Workshop, (2) five plenary talks, (3) evidence-based comments from four breakout groups, and (4) discussions during report-back sessions. Current evidence reviewed from the proceedings from the Workshop does not support an association between GH replacement and primary tumour or cancer recurrence. The effect of GH replacement on secondary neoplasia risk is minor compared to host- and tumour treatment-related factors. There is no evidence for an association between GH replacement and increased mortality from cancer amongst GH-deficient childhood cancer survivors. Patients with pituitary tumour or craniopharyngioma remnants receiving GH replacement do not need to be treated or monitored differently than those not receiving GH. GH replacement might be considered in GH-deficient adult cancer survivors in remission after careful individual risk/benefit analysis. In children with cancer predisposition syndromes, GH treatment is generally contraindicated but may be considered cautiously in select patients.

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Individuals surviving cancer and brain tumors may experience growth hormone (GH) deficiency as a result of tumor growth, surgical resection and/or radiotherapy involving the hypothalamic-pituitary region. Given the pro-mitogenic and anti-apoptotic properties of GH and insulin-like growth factor-I, the safety of GH replacement in this population has raised hypothetical safety concerns that have been debated for decades. Data from multicenter studies with extended follow-up have generally not found significant associations between GH replacement and cancer recurrence or mortality from cancer among childhood cancer survivors. Potential associations with secondary neoplasms, especially solid tumors, have been reported, although this risk appears to decline with longer follow-up. Data from survivors of pediatric or adult cancers who are treated with GH during adulthood are scarce, and the risk versus benefit profile of GH replacement of this population remains unclear. Studies pertaining to the safety of GH replacement in individuals treated for nonmalignant brain tumors, including craniopharyngioma and non-functioning pituitary adenoma, have generally been reassuring with regards to the risk of tumor recurrence. The present review offers a summary of the most current medical literature regarding GH treatment of patients who have survived cancer and brain tumors, with the emphasis on areas where active research is required and where consensus on clinical practice is lacking.

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Growth hormone deficiency (GHD) is a rare but treatable cause of short stature. The diagnosis requires a careful evaluation of clinical history, physical examination and appropriate interpretation of longitudinal growth, with specific features for each period of life. Other clinical findings, in addition to growth failure, may be present and can be related to the etiology and to associated hormone deficiencies. Despite more than 50 years since the first reports of provocative tests of growth hormone (GH) secretion for the diagnosis of GHD, the interpretation of the results remains a matter of debate. When GHD is confirmed, GH treatment is recommended. Treatment is effective and safe, but requires daily injections during many years, which can affect adherence. At the end of longitudinal growth, during the transition phase, it might be necessary to re-evaluate GH secretion. This review summarizes and updates the recent information related to GHD in children, as well the recommendations for treatment.

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CONTEXT: Children born prematurely have been treated with growth hormone (GH), and a significant improvement in height during the first years of treatment has been described. OBJECTIVE: To evaluate the influence of prematurity on near-adult height (NAH) after GH treatment. DESIGN: KIGS (Pfizer International Growth Database) was queried for children born preterm treated with GH. SETTING: KIGS database. PATIENTS: A total of 586 children short in stature born preterm with various GH status and with available gestational age (GA), birth weight, and NAH, all treated with GH. INTERVENTION: GH treatment. MAIN OUTCOME MEASURE: NAH. RESULTS: Values were expressed as median. From the 586 children included, 482 born appropriate for GA (AGA; median age 8.26 years) and 104 born small for gestational age (SGA) (median age 8.54 years); 66.6% of preterm AGA had GH peak < 7 µg/L during a provocation test, whereas only 8.6% of preterm SGA. Change in height standard deviation scores (SDS) from GH start to NAH after 8.04 years of GH treatment was 1.82 in preterm AGA. Respective values were 7.08 years and 1.08 SDS for preterm SGA (P < 0.001); 57% of the variability of the growth response to NAH could be explained, and the distance to parental height was the strongest predictor. No significant changes in height SDS were observed from puberty start to NAH. No correlation was found with GA. GH treatment was well tolerated. CONCLUSION: GH treatment resulted in significant improvement in height in children born preterm, particularly during prepubertal years and for those with GH deficiency. The degree of prematurity did not influence the growth response.

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OBJECTIVES: To discuss the etiology and growth consequences of small size at birth and the indications, effects, and safety of biosynthetic growth hormone therapy in children born small for gestational age. SOURCE OF DATA: A comprehensive and non-systematic search was carried out in the PubMed, LILACS, and SciELO databases from 1980 to the present day, using the terms "small for gestational age," "intrauterine growth restriction," and "growth hormone". The publications were critically selected by the authors. DATA SYNTHESIS: Although the majority of children born small for gestational age show spontaneous catch-up growth during the first two years of life, some of them remain with short stature during childhood, with high risk of short stature in adult life. Treatment with growth hormone might be indicated, preferably after 2-4 years of age, in those small for gestational age children who remain short, without catch-up growth. Treatment aims to increase growth velocity and to reach a normal height during childhood and an adult height within target height. Response to growth hormone treatment is variable, with better growth response during the pre-pubertal period. CONCLUSIONS: Treatment with growth hormone in short children born small for gestational age is safe and effective to improve adult height. Efforts should be done to identify the etiology of small size at birth before treatment.

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Abstract Objectives: To discuss the etiology and growth consequences of small size at birth and the indications, effects, and safety of biosynthetic growth hormone therapy in children born small for gestational age. Source of data: A comprehensive and non-systematic search was carried out in the PubMed, LILACS, and SciELO databases from 1980 to the present day, using the terms "small for gestational age," "intrauterine growth restriction," and "growth hormone". The publications were critically selected by the authors. Data synthesis: Although the majority of children born small for gestational age show spontaneous catch-up growth during the first two years of life, some of them remain with short stature during childhood, with high risk of short stature in adult life. Treatment with growth hormone might be indicated, preferably after 2-4 years of age, in those small for gestational age children who remain short, without catch-up growth. Treatment aims to increase growth velocity and to reach a normal height during childhood and an adult height within target height. Response to growth hormone treatment is variable, with better growth response during the pre-pubertal period. Conclusions: Treatment with growth hormone in short children born small for gestational age is safe and effective to improve adult height. Efforts should be done to identify the etiology of small size at birth before treatment.

Resumo Objetivos: Discutir a etiologia e as consequências para o crescimento e as indicações, os efeitos e a segurança da terapia com hormônio de crescimento biossintético em crianças pequenas para idade gestacional. Fonte dos dados: Uma busca abrangente e não sistemática foi feita nas bases de dados PubMed, LILACS e SciELO de 1980 até a presente data, com os termos "small for gestational age" (pequeno para a idade gestacional), "intrauterine growth restriction" (restrição de crescimento intrauterino) e "growth hormone" (hormônio do crescimento). As publicações foram selecionadas criticamente pelos autores. Síntese dos dados: Embora a maioria das crianças nascidas pequenas para idade gestacional apresente recuperação espontânea do crescimento durante os dois primeiros anos de vida, algumas delas permanecem com baixa estatura durante a infância, com alto risco de baixa estatura na vida adulta. O tratamento com hormônio de crescimento pode ser indicado, preferencialmente após os dois aos quatro anos, naquelas crianças sem recuperação espontânea do crescimento e com baixa estatura. Seus objetivos são aumentar a velocidade de crescimento e atingir uma altura normal durante a infância e uma altura adulta dentro da altura-alvo. A resposta ao tratamento com hormônio de crescimento é variável, com melhor resultado se iniciado durante o período pré-puberal. Conclusões: O tratamento com hormônio de crescimento em crianças baixas nascidas pequenas para idade gestacional é seguro e eficaz para melhorar a estatura adulta. Esforços devem ser feitos para identificar a etiologia do nascimento pequenas para idade gestacional antes do tratamento.

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OBJECTIVES: A sedentary lifestyle is increasingly implicated in a negative metabolic health profile among youth. The present study examined relationships between clustered metabolic risk factors and TV viewing in female adolescents. METHODS: The sample comprised 262 girls 14-17 years. Height, weight, fasting glucose, insulin, HDL cholesterol, triglycerides, and blood pressure were measured. Body mass index (BMI) was calculated. TV viewing time and moderate-to-vigorous physical activity (MVPA) were estimated from a 3-day diary. Outcome variables were normalized and expressed as Z scores which were summed into a metabolic risk score. Multiple linear regression analysis was used. RESULTS: TV viewing was independently associated with increased prevalence of clustered metabolic risk in girls after adjustment for several confounders (i.e., chronological age, BMI, MVPA, and parental education). The final model also indicated that lower levels of MVPA, higher BMI, and lower mother education were associated with higher metabolic risk. CONCLUSIONS: Increased TV viewing had an adverse effect on metabolic health of adolescent girls. The findings highlight the potential importance of preventive actions to ameliorate metabolic risk in youth which target both sedentary and physically active behaviors.

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BACKGROUND: Evaluation of lipid profile in children and adolescents is important for early diagnosis of dyslipidemias. Physiological changes might be observed in the concentration of the lipid profile components, according to the stage of sexual maturation. OBJECTIVE: To evaluate the variation in lipid and lipoprotein concentrations in boys during puberty. METHODS: The sample consisted of 570 male adolescents with ages between 10 and 17 years. Weight, height, and body mass index (BMI) were assessed. Total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and triglyceride (TG) were determined by the enzymatic method, and low-density lipoprotein cholesterol (LDL-C) was calculated. Puberty was classified according to Tanner references. The percentile criterion was adopted for the distribution and identification of lipoprotein levels. The analysis of variance and description tests with p<0.05 was applied. RESULTS: Participants had similar BMI z-score and physical activity habits in all groups. A significant reduction in TC and HDL-C concentrations between the start and end of puberty was observed. LDL-C levels rose during stage 3 of development, decreasing at the end of the pubertal process. TG levels did not change significantly with pubertal status. CONCLUSION: Lipid and lipoprotein concentrations tend to undergo changes during puberty in boys. The use of percentile values can be very useful to track variations in lipid and lipoprotein levels during the maturation process.

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BACKGROUND: Associations of metabolic syndrome (MetS) with lifestyle behaviors in youth is potentially important for identifying subgroups at risk and encourage interventions. This study evaluates the associations among the clustering of metabolic risk factors and moderate-to-vigorous physical activity (MVPA) in youth. METHODS: The sample comprised 522 girls and 402 boys (N = 924) aged 11 to 17 years. Height, weight, waist circumference (WC), fasting glucose, high-density lipoprotein cholesterol, triglycerides, and blood pressures were measured. Cardiorespiratory fitness (CRF) was assessed using the 20-m shuttle run test. MVPA was estimated with a 3-day diary. Outcome variables were statistically normalized and expressed as z scores. A clustered metabolic risk score was computed as the mean of z scores. Multiple linear regression was used to test associations between metabolic risk and MVPA by sex, adjusted for age, WC, and CRF. RESULTS: After adjustment for potential confounders, MVPA was inversely associated with the clustering of metabolic risk factors in girls, but not in boys; in addition, after adjusting for WC, the statistical model of that relationship was substantially improved in girls. CONCLUSION: MVPA was independently associated with increased risk of MetS in girls. Additional efforts are needed to encourage research with different analytical approach and standardization of criteria for MetS in youth.

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