Adult height in boys and girls with untreated short stature and constitutional delay of growth and puberty: accuracy of five different methods of height prediction

Which method is more effective in predicting adult height in pubertal girls treated with gonadotropin-releasing hormone agonist?

PURPOSE

The aim of the present study was to determine the efficiency of three different predictive models [Bayley-Pinneau (BP), Roche-Wainer-Thissen (RWT), and Tanner-Whitehouse 2 (TW2)] by comparing their predictions with near-adult height data of girls receiving gonadotropin-releasing hormone agonist (GnRHa) therapy.

METHODS

Clinical findings were retrospectively analyzed. Bone ages obtained before treatment were evaluated from left hand and wrist radiographs by three researchers. Predicted adult height (PAH) was calculated using the BP, RWT, and TW2 methods for each patient at the beginning of therapy.

RESULTS

The median age at diagnosis of the 48 patients included in the study was 8.8 (8.9-9.3) years. There was no significant difference between the mean bone ages evaluated separately with the Greulich-Pyle atlas and the TW3-RUS method (p=0.34). Among the PAH methods, only PAH measured by the BP method was very close to and no different from near adult height (NAH) [159.8±6.3 vs. 158.8±9.3 cm. p=0.3; (-0.5±1.1) vs. (-0.7±1.6) standard deviation score, p=0.1]. Accordingly, the BP method was found to be the most accurate prediction tool in girls with puberty treated with GnRHa.

CONCLUSION

The BP method is more effective at predicting adult height than the RWT and TW2 methods in female patients who will receive GnRHa treatment.

Efficacy and safety of a 4-year combination therapy of growth hormone and gonadotropin-releasing hormone analogue in pubertal girls with short predicted adult height

OBJECTIVES

To improve adult height in pubertal girls with a poor height prediction, treatment with growth hormone (GH) can be used in combination with a gonadotropin releasing hormone agonist (GnRHa), to delay closure of the growth plates. However, there are few studies to support this practice, and they show conflicting results. The objective of this trial is to assess the safety and efficacy of this combination treatment in early pubertal girls with a short predicted height, in comparison with matched controls.

DESIGN PATIENTS AND METHODS

We designed an open-label, multicenter, interventional case-control study. Early pubertal girls with predicted adult height (PAH) below -2.5 SDS, were recruited in tertiary care centers in Belgium. They were treated for four years with GH and GnRHa. The girls were followed until adult height (AH) was reached. AH vs PAH, AH vs Height at start, and AH vs Target Height (TH) were evaluated, as well as safety parameters. Control data were assembled from historical patient files or from patients who preferred not to participate in the study.

RESULTS

Sixteen girls with mean age ( ± SD) at start of 11.0 years (± 1.3) completed the study protocol and follow-up. Their mean height ( ± SD) increased from 131.3 ± 4.1 cm (-2.3 ± 0.7 SDS) at start of treatment to 159.8 ± 4.7 cm (-1.1 ± 0.7 SDS) at AH. In matched controls, height increased from 132.3 ± 4.2 cm (-2.4 ± 0.5 SDS) to 153.2 ± 3.4 cm (-2.1 ± 0.6 SDS) (p<0.001). AH surpassed initial PAH by 12.0 ± 2.6 cm in treated girls; and by 4.2 ± 3.6 cm in the controls (p<0.001). Most treated girls reached normal adult height (>-2SD) (87.5%) and 68.7% reached or superseded the target height (TH), which was the case in only a minority of the controls (37.5% and 6.2%, respectively) (p= 0.003 and 0.001). A serious adverse event possibly related to the treatment, was a fracture of the metatarsals.

CONCLUSION

A four-year GH/GnRHa treatment in early pubertal girls with a poor PAH seems safe and results in a clinically relevant and statistically significant increase in AH compared with matched historical controls.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, identifier NCT00840944.

A Novel Method for Adult Height Prediction in Children with Idiopathic Short Stature Derived from a German-Dutch Cohort

Context

Prediction of adult height (AH) is important in clinical management of short children. The conventional methods of Bayley-Pinneau (BP) or Roche-Wainer-Thissen (RWT) have limitations.

Objective

We aimed to develop a set of algorithms for AH prediction in patients with idiopathic short stature (ISS) which are specific for combinations of predicting variables.

Methods

Demographic and auxologic data were collected in childhood (1980s) and at AH (1990s). Data were collected by Dutch and German referral centers for pediatric endocrinology. A total of 292 subjects with ISS (219 male, 73 female) were enrolled. The population was randomly split into modeling (n = 235) and validation (n = 57) cohorts. Linear multi-regression analysis was performed with predicted AH (PAH) as response variable and combinations of chronological age (CA), baseline height, parental heights, relative bone age (BA/CA), birth weight, and sex as exploratory variables.

Results

Ten models including different exploratory variables were selected with adjusted R² ranging from 0.84 to 0.78 and prediction errors from 3.16 to 3.68 cm. Applied to the validation cohort, mean residuals (PAH minus observed AH) ranged from −0.29 to −0.82 cm, while the conventional methods showed some overprediction (BP: +0.53 cm; RWT: +1.33 cm; projected AH: +3.81 cm). There was no significant trend of residuals with PAH or any exploratory variables, in contrast to BP and projected AH.

Conclusion

This set of 10 multi-regression algorithms, developed specifically for children with ISS, provides a flexible tool for AH prediction with better accuracy than the conventional methods.

Tanner-Whitehouse and Modified Bayley-Pinneau Adult Height Predictions in Elite Youth Soccer Players from the Middle East

PURPOSE

To provide the first scrutiny of adult height prediction protocols based on automated Greulich-Pyle and Tanner-Whitehouse (TW) skeletal ages applied to elite youth soccer players from the Middle East.

METHODS

We examined the application of modified Bayley-Pinneau (BoneXpert®), TW-II, and TW-III protocols using mixed-longitudinal data available for 103 subjects (chronological age range, 19.4 to 27.9 yr) previously enrolled as academy student-athletes (annual screening range, one to six visits). Random-effects generalized additive models quantified the presence of systematic mean differences between actual versus predicted adult height. Effects were deemed practically equivalent based on the location of the confidence interval (95% CI) against a realistic difference value of Δ = ± 1 cm. Each model pooled residual standard deviation described the actual precision of height predictions and was used to calculate a 95% prediction interval.

RESULTS

The BoneXpert® method overpredicted adult height systematically at chronological ages in the range of approximately 13.5 to 14.5 yr (95% CI range, -1.9 to -1 cm) and Greulich-Pyle skeletal ages between 13.5 and 15 yr (95% CI range, -3.1 to -1 cm). Effects based on TW-II were practically equivalent across the chronological and skeletal age measurement ranges, with this protocol yielding adult height predictions with a precision (standard deviation) of approximately ±2.6 cm. The mean TW-III effects indicated systematic adult height overpredictions until the attainment of 14.5 and 15 yr of chronological age (95% CI range, -3.8 to -1.1 cm) and TW-III skeletal age (95% CI range: -5.2 to -2.3 cm), respectively.

CONCLUSIONS

Tanner-Whitehouse-II adult height prediction method provided more consistent estimates and can be considered the method of choice for talent development purposes in youth soccer players from the Middle East.

Comparison of the Effectiveness of Adult Height Prediction Methods in Children with Growth Hormone Deficiency

Background: In patients with growth hormone (GH) deficiency, the prediction of adult height before initiation of GH treatment can be helpful to guide clinicians and families. However, data regarding the effectiveness of prediction methods in such patients are limited.Objective: We aimed to investigate the accuracy of the three most used adult height prediction methods [Bayley-Pinneau (BP), Roche-Wainer-Thissen (RWT), and Tanner-Whitehouse 2 (TW2)] by comparing their results with the near-adult height (NAH) data of children treated with GH.Methods: A single-center retrospective study was conducted including patients treated with somatotropin due to GH deficiency. Bone age radiographs were reread by three authors. Adult height predictions were made using BP, RWT, and TW2 methods for each patient.Results: Forty-nine patients with GH deficiency [median age at diagnosis 10.8 (9.2-12.0) years, 63.3% girls, 69.4% prepubertal] were included. Median differences between predicted adult height (PAH) and NAH standard deviation (SD) scores were -0.5, 0.0, and 0.3 for BP, RWT, and TW2 methods, respectively. The rates of PAH within ±1 SD score of NAH were 54.7%, 62.3%, and 77.4% for BP, TW2, and RWT methods, respectively. RWT was the most accurate method in girls, however, it showed a similar efficiency with TW2 in prepubertal patients or those with delayed bone age between 1-2 years, independent of gender.Conclusions: We found that RWT and TW2 methods may be preferable rather than the BP method for predicting adult height in patients with a diagnosis of GH deficiency.

Prediction of Adult Height by Machine Learning Technique

CONTEXT

Prediction of AH is frequently undertaken in the clinical setting. The commonly used methods are based on the assessment of skeletal maturation. Predictive algorithms generated by machine learning, which can already automatically drive cars and recognize spoken language, are the keys to unlocking data that can precisely inform the pediatrician for real-time decision making.

OBJECTIVE

To use machine learning (ML) to predict adult height (AH) based on growth measurements until age 6 years.

METHODS

Growth data from 1596 subjects (798 boys) aged 0-20 years from the longitudinal GrowUp 1974 Gothenburg cohort were utilized to train multiple ML regressors. Of these, 100 were used for model comparison, the rest was used for 5-fold cross-validation. The winning model, random forest (RF), was first validated on 684 additional subjects from the 1974 cohort. It was additionally validated using 1890 subjects from the GrowUp 1990 Gothenburg cohort and 145 subjects from the Edinburgh Longitudinal Growth Study cohort.

RESULTS

RF with 51 regression trees produced the most accurate predictions. The best predicting features were sex and height at age 3.4-6.0 years. Observed and predicted AHs were 173.9 ± 8.9 cm and 173.9 ± 7.7 cm, respectively, with prediction average error of -0.4 ± 4.0 cm. Validation of prediction for 684 GrowUp 1974 children showed prediction accuracy r = 0.87 between predicted and observed AH (R2 = 0.75). When validated on the 1990 Gothenburg and Edinburgh cohorts (completely unseen by the learned RF model), the prediction accuracy was r = 0.88 in both cases (R2 = 0.77). AH in short children was overpredicted and AH in tall children was underpredicted. Prediction absolute error correlated negatively with AH (P < .0001).

CONCLUSION

We show successful, validated ML of AH using growth measurements before age 6 years. The most important features for prediction were sex, and height at age 3.4-6.0. Prediction errors result in over- or underestimates of AH for short and tall subjects, respectively. Prediction by ML can be generalized to other cohorts.

Differential diagnosis between constitutional delay of growth and puberty, idiopathic growth hormone deficiency and congenital hypogonadotropic hypogonadism: a clinical challenge for the pediatric endocrinologist

INTRODUCTION

Differential diagnosis between constitutional delay of growth and puberty (CDGP), partial growth hormone deficiency (pGHD) and congenital hypogonadotropic hypogonadism (cHH) may be difficult. All these conditions usually present with poor growth in pre- or peri-pubertal age and they may recur within one familial setting, constituting a highly variable, but somehow common, spectrum of pubertal delay.

EVIDENCE ACQUISITION

Narrative review of the most relevant English papers published between 1981 and march 2020 using the following search terms "constitutional delay of growth and puberty," "central hypogonadism," "priming," "growth hormone deficiency," "pituitary," "pituitary magnetic resonance imaging," with a special regard to the latest scientific acquisitions.

EVIDENCE SYNTHESIS

CDGP is by far the most prevalent entity in boys and recurs within families. pGHD is a rare, often idiopathic and transient condition, where hypostaturism presents more severely. Specificity of pGHD diagnosis is increased by priming children before growth hormone stimulation test (GHST); pituitary MRI and genetic analysis are recommended to personalize future follow-up. Diagnosing cHH may be obvious when anosmia and eunuchoid proportions concomitate. However, cHH can either overlap with pGHD in forms of multiple pituitary hormone deficiencies (MPHD) or syndromic conditions either with CDGP in family pedigrees, so endocrine workup and genetic investigations are necessary. The use of growth charts, bone age, predictors of adult height, primed GHST and low dose sex steroids (LDSS) treatment are recommended.

CONCLUSIONS

Only a step-by-step diagnostic process based on appropriate endocrine and genetic markers together with LDSS treatment can help achieving the correct diagnosis and optimizing outcomes.

Adult height prediction by bone age determination in children with isolated growth hormone deficiency

BACKGROUND

The precision of adult height prediction by bone age determination in children with idiopathic growth hormone deficiency (IGHD) is unknown.

METHODS

The near adult height (NAH) of patients with IGHD in the KIGS database was compared retrospectively to adult height prediction calculated by the Bayley-Pinneau (BP) prediction based on bone age by Greulich-Pyle (GP) in 315 children and based on the Tanner-Whitehouse 2 (TW2) method in 121 children. Multiple linear regression analyses adjusted for age at GH start, age at puberty, mean dose and years of of GH treatment, and maximum GH peak in stimulation test were calculated.

RESULTS

The mean underestimation of adult height based on the BP method was at baseline 4.1 ± 0.7 cm in girls and 6.1 ± 0.6 cm in boys, at 1 year of GH treatment 2.5 ± 0.5 cm in girls and 0.9 ± 0.4 cm in boys, while at last bone age determination adult height was overestimated in mean by 0.4 ± 0.6 cm in girls and 3.8 ± 0.5 cm in boys. The mean underestimation of adult height based on the TW2 method was at baseline 5.3 ± 2.0 cm in girls and 7.9 ± 0.8 cm in boys, at 1 year of GH treatment adult height was overestimated in girls 0.1 ± 0.6 cm in girls and underestimated 4.1 ± 0.4 cm in boys, while at last bone age determination adult height was overestimated in mean by 3.1 ± 1.5 cm in girls and 3.6 ± 0.8 cm in boys.

CONCLUSIONS

Height prediction by BP and TW2 at onset of GH treatment underestimates adult height in prepubertal IGHD children, while in mean 6 years after onset of GH treatment these prediction methods overestimated adult height.

Serine racemase enhances growth of colorectal cancer by producing pyruvate from serine

Serine racemase (SRR) catalyses not only the racemization but also the dehydration of L-serine and D-serine, resulting in the formation of pyruvate and ammonia. Although SRR activity is important in the central nervous system, SRR has not been linked to cancer metabolism before. Here we show that SRR supports proliferation of colorectal-cancer cells. We find that SRR expression is upregulated in colorectal adenoma and adenocarcinoma lesions compared with non-neoplastic mucosa in human colorectal-cancer specimens. SRR-mediated dehydration of serine contributes to the pyruvate pool in colon-cancer cells, enhances proliferation, maintains mitochondrial mass and increases basal reactive oxygen species production, which has anti-apoptotic effects. Moreover, SRR promotes acetylation of histone H3 by maintaining intracellular acetyl-CoA levels. Inhibition of SRR suppresses growth of colorectal tumours in mice and augments the efficacy of 5-fluorouracil treatment. Our findings highlight a previously unknown mechanism through which a racemase supports cancer-cell growth and suggest that SRR might be a molecular target for colorectal-cancer therapy.

A New Model of Adult Height Prediction Validated in Boys with Constitutional Delay of Growth and Puberty

BACKGROUND

For children with retarded bone ages such as in constitutional delay of growth and puberty (CDGP) there are no specific methods to predict adult height based on bone age. Widely used methods such as Bayley-Pinneau (BP) tend to overestimate adult height in CDGP.

OBJECTIVE

We aimed to develop a specific adult height prediction model for teenage boys with retarded bone ages >1 year.

METHODS

Based on the adult heights of 68 males (median age 22.5 years) a new height prediction model was calculated based on 105 height measurements and bone age determinations at a median age of 14.0 years. The new model was adapted for the degree of bone age retardation and validated in an independent cohort of 32 boys with CDGP.

RESULTS

The BP method overestimated adult height (median +1.2 cm; p = 0.282), especially in boys with a bone age retardation ≥2 years (median +1.6 cm; p = 0.027). In the validation study, there was no significant difference between adult height and predicted adult height based on the new model (p = 0.196), while the BP model led to a significant overestimation of predicted adult height (median +4.1 cm; p = 0.009).

CONCLUSIONS

The new model to predict adult height in boys with CDGP provides novel indices for height predictions in bone ages >13 years and is adapted to different degrees of bone age retardation. The new prediction model has a good predictive capability and overcomes some of the shortcomings of the BP model.

Effects of the Timing of Sex-Steroid Exposure in Adolescence on Adult Health Outcomes

CONTEXT

Variation in pubertal timing is associated with a wide range of adult risks and outcomes, but it is unclear whether these associations are causal, and it is largely unknown whether these associations can be modified by treatment.

EVIDENCE ACQUISITION

We conducted PubMed searches to identify Mendelian randomization (MR) studies on the influence of pubertal timing on adult health and studies on sex-steroid treatment of the following conditions associated with reduced reproductive endocrine function in adolescence: constitutional delay, Turner syndrome, and Klinefelter syndrome.

EVIDENCE SYNTHESIS

Results of MR studies suggest that earlier pubertal timing increases body mass index; increases risk for breast, ovarian, endometrial, and prostate cancers; elevates fasting glucose levels and blood pressure; impairs lung capacity and increases risk for asthma; leads to earlier sexual intercourse and first birth; decreases time spent in education; and increases depressive symptoms in adolescence. Later pubertal timing appears to lower bone mineral density (BMD). Although studies of constitutional delay have not shown that sex-steroid treatment alters adult height or BMD, studies of girls with Turner syndrome and boys with Klinefelter syndrome suggest that earlier initiation of sex-steroid treatment improves physical and neurocognitive outcomes.

CONCLUSIONS

Despite having some limitations, MR studies suggest that pubertal timing causally influences many adult conditions and disease risks. Studies of Turner syndrome and Klinefelter syndrome suggest that earlier sex-steroid exposure may have short- and long-term benefits. The mechanisms underlying these findings and the effects of trends and treatments affecting pubertal timing remain to be determined.

Delayed Puberty-Phenotypic Diversity, Molecular Genetic Mechanisms, and Recent Discoveries

This review presents a comprehensive discussion of the clinical condition of delayed puberty, a common presentation to the pediatric endocrinologist, which may present both diagnostic and prognostic challenges. Our understanding of the genetic control of pubertal timing has advanced thanks to active investigation in this field over the last two decades, but it remains in large part a fascinating and mysterious conundrum. The phenotype of delayed puberty is associated with adult health risks and common etiologies, and there is evidence for polygenic control of pubertal timing in the general population, sex-specificity, and epigenetic modulation. Moreover, much has been learned from comprehension of monogenic and digenic etiologies of pubertal delay and associated disorders and, in recent years, knowledge of oligogenic inheritance in conditions of GnRH deficiency. Recently there have been several novel discoveries in the field of self-limited delayed puberty, encompassing exciting developments linking this condition to both GnRH neuronal biology and metabolism and body mass. These data together highlight the fascinating heterogeneity of disorders underlying this phenotype and point to areas of future research where impactful developments can be made.

Characteristic dynamics of height and weight in preschool boys with constitutional delay of growth and puberty or hypogonadotropic hypogonadism

OBJECTIVE

Constitutional delay of growth and puberty (CDGP) is a frequent variant of the normal leading to short stature and/or pubertal delay. To distinguish CDGP from hypogonadotropic hypogonadism (HH), we evaluated height, growth and weight pattern of CDGP and HH in the first 5 years of life.

DESIGN AND PATIENTS

We studied retrospectively height and weight in the first 5 years (y) of life in 54 boys with CDGP and 8 boys with HH.

RESULTS

In boys with CDGP, height-SDS decreased (change -0.94 (interquartile range [IQR] -1.69 to -0.05); P < 0.001) between birth and 2 years. BMI-SDS decreased (change -0.38 (IQR -1.21-0.16); P < 0.001) in the same time period. There were no significant changes in height-SDS or BMI-SDS between 2 years and 5 years, while height-SDS (change + 1.49 (IQR 1.02-1.95); P < 0.001) and BMI-SDS (change + 0.91 (IQR 0.12-1.69); P < 0.001) increased between pubertal and adult age. In boys with HH, height-SDS and BMI-SDS did not change significantly in the first 5 years of life. Height-SDS decreased (change -1.39 (IQR -1.96 to -0.67); P = 0.018) significantly between 5 years of life and puberty, while there were no significant changes in BMI-SDS in this time period. At pubertal age, BMI-SDS was significantly (P = 0.001) higher in boys with HH compared with boys with CDGP.

CONCLUSION

Height deflection and weight deflection in CDGP occur already during the first two years of life in contrast to HH. This different pattern of growth and weight might be helpful to distinguish CDGP from HH.

Management of hypogonadism from birth to adolescence

Management of patients with hypogonadism is dependent on the underlying cause. Whilst functional hypogonadism presenting as delayed puberty in adolescence is relatively common, permanent hypogonadism presenting in infancy or adolescence is unusual. The main differential diagnoses of delayed puberty include self-limited delayed puberty (DP), idiopathic hypogonadotropic hypogonadism (IHH) and hypergonadotropic hypogonadism. Treatment of self-limited DP involves expectant observation or short courses of low dose sex steroid supplementation. More complex and involved management is required in permanent hypogonadism to achieve both development of secondary sexual characteristics and to maximize the potential for fertility. This review will cover the options for management involving sex steroid or gonadotropin therapy, with discussion of benefits, limitations and specific considerations of the different treatment options.

Near final height in Korean children referred for evaluation of short stature: clinical utility and analytical validity of height prediction methods

PURPOSE

Predicted adult height (PAH) is often crucial to decision-making about treatment with human growth hormone (GH) or gonadotropin-releasing hormone agonist in children with short stature. This study compares final adult height (FAH) with different methods used to determine PAH and assesses the clinical utility and analytical validity of height prediction for children not treated with GH.

METHODS

Clinical findings were retrospectively analyzed, and the heights of 44 children (22 males and 22 females) who visited our clinic between August 2006 and June 2017 and reached near final adult height (NFAH) were evaluated. Children treated with GH were excluded. We compared measured NFAH to PAH using the Bayley-Pinneau (BP), Tanner-Whitehouse Mark 2, and Roche-Wainer-Thissen (RWT) methods.

RESULTS

Pearson correlation between all 3 prediction methods and NFAH showed high positive correlations in males and females (P<0.05). The average difference between PAH and NFAH for the BP method (0.4±3.9 cm) was significantly lower than those for the RWT and TW 2 methods in females (P=0.000, analysis of variance). Furthermore, only PAH by the BP method in females was very close to measured NFAH (paired t-test). A Bland-Altman plot verified that 95% of the differences between the PAH and NFAH exist between limits of agreement (mean±1.96 standard deviation).

CONCLUSIONS

The BP method is more useful to predict NFAH in females than other methods. Careful attention is still required when using such tools because PAH can be inaccurate. Therefore, a more accurate FAH prediction model for Korean children is needed.

Effects of Astragalus Extract Mixture HT042 on Height Growth in Children with Mild Short Stature: A Multicenter Randomized Controlled Trial

HT042 is a standardized functional food ingredient approved by Korean Food and Drug Administration with a claim 'HT042 can help height growth of children'. We aimed to evaluate the safety and efficacy of HT042 on height growth in children with mild short stature. A multicenter, randomized, double-blind, placebo-controlled parallel study was performed on children aged 6-8 years with height ranked below the 25th percentile. In 129 children, height gain was significantly higher in HT042 group than placebo group after 24 weeks (mean difference, 0.29 cm; 95% CI, 0.01 to 0.57 cm; p = 0.027). The difference was elevated when the efficacy analysis was restricted to children below the 10th percentile (mean difference, 0.45 cm; 95% CI, 0.04 to 0.87 cm; p = 0.031). Because bone age advancement was lower in HT042 group, height standard deviation score gain for bone age was higher in HT042 group and the difference was significant in children below the 10th percentile (mean difference, 0.20 score; 95% CI, 0.00 to 0.39 points; p = 0.045). Serum IGF-1 and IGFBP-3 levels were significantly increased compared with baseline within HT042 group, but group difference was not significant. HT042 supplementation helped to increase height growth in children without skeletal maturation and was more effective in much shorter children. The effects might be mediated by increases in serum IGF-1 and IGFBP-3 levels. Copyright © 2017 John Wiley & Sons, Ltd.

Adult Consequences of Self-Limited Delayed Puberty

Delayed puberty is a common condition defined as the lack of sexual maturation by an age ≥2 SD above the population mean. In the absence of an identified underlying cause, the condition is usually self-limited. Although self-limited delayed puberty is largely believed to be a benign developmental variant with no long-term consequences, several studies have suggested that delayed puberty may in fact have both harmful and protective effects on various adult health outcomes. In particular, height and bone mineral density have been shown to be compromised in some studies of adults with a history of delayed puberty. Delayed puberty may also negatively affect adult psychosocial functioning and educational achievement, and individuals with a history of delayed puberty carry a higher risk for metabolic and cardiovascular disorders. In contrast, a history of delayed puberty appears to be protective for breast and endometrial cancer in women and for testicular cancer in men. Most studies on adult outcomes of self-limited delayed puberty have been in small series with significant variability in outcome measures and study criteria. In this article, we review potential medical and psychosocial issues for adults with a history of self-limited delayed puberty, discuss potential mechanisms underlying these issues, and identify gaps in knowledge and directions for future research.

Fertility Issues for Patients with Hypogonadotropic Causes of Delayed Puberty

Delayed puberty presenting with low gonadotropins has multiple causes. Self-limited delay (constitutional delay) is generally considered benign, but adult height and bone mineral density may be compromised, and fertility has not been studied. Functional hypogonadotropic hypogonadism due to a stressor is thought to resolve with removal of the stressor, but reproductive endocrine dysfunction can sometimes persist. Most but not all patients with idiopathic hypogonadotropic hypogonadism, a typically long-lasting condition, can achieve fertility with exogenous hormone therapy. Future studies are needed to determine fertility outcomes in self-limited delayed puberty and to more clearly define prognostic factors for fertility in functional and idiopathic hypogonadotropic hypogonadism.

Bone age: assessment methods and clinical applications

The main bone age assessment methods are the Greulich-Pyle and Tanner-Whitehouse 2 methods, both of which involve left hand and wrist radiographs. Several other bone age assessment methods have been developed, including ultrasonographic, computerized, and magnetic resonance (MR) imaging methods. The ultrasonographic method appears unreliable in children with delayed and advanced bone age. MR imaging is noninvasive; however, bone age assessment using MR imaging is relatively new, and further examinations are needed. An automated method for determining bone age, named BoneXpert, has been validated for Caucasian children with growth disorders and children of various ethnic groups. Sex hormones are necessary for bone growth and maturation in children with a bone age corresponding to normal pubertal age, and estrogen is essential for growth plate closure. Bone age is an effective indicator for diagnosing and treating various diseases. A new method for adult height prediction based on bone age has been developed using BoneXpert, in addition to the commonly used Bayley-Pinneau and Tanner-Whitehouse mark II methods. Furthermore, bone age may become a predictor for the timing of peak height velocity and menarche.

Constitutional delay influences the auxological response to growth hormone treatment in children with short stature and growth hormone sufficiency

In a retrospective, population based cohort study, we examined whether constitutional delay was associated with the growth response to growth hormone (GH) in children with short stature and normal GH responses. 70 patients were treated with 21 GH iu/m2/week from 1975 to 2013 throughout New Zealand. Demographic and auxological data were prospectively collected and standard deviation scores (SDS) were calculated for height (HtSDS), yearly growth velocity (GV-SDS), body mass index (BMI-SDS) and predicted adult height (PAH-SDS) at time of the last available bone age. In the first year, GH was associated with marked increase in HtSDS (+0.46 (0.19, 0.76), p < 0.001) and GV-SDS (from −1.9 (−3.6, −0.7) to +2.7 (0.45, 4.2), p < 0.001). The increase in HtSDS but not in GV-SDS was greatest with younger patients and greater bone age delay, with no effect of sex, BMI-SDS or baseline HtSDS. PAH-SDS increased with treatment (+0.94 (0.18, 1.5)); increased PAH-SDS was associated with less bone age delay and greater initial increase in HtSDS. This study shows that greater bone age delay was associated with greater initial improvement in height but less improvement in predicted adult heights, suggesting that children with very delayed bone ages may show accelerated maturation during GH treatment.

Role of intensive training in the growth and maturation of artistic gymnasts

Short stature and later maturation of youth artistic gymnasts are often attributed to the effects of intensive training from a young age. Given limitations of available data, inadequate specification of training, failure to consider other factors affecting growth and maturation, and failure to address epidemiological criteria for causality, it has not been possible thus far to establish cause–effect relationships between training and the growth and maturation of young artistic gymnasts. In response to this ongoing debate, the Scientific Commission of the International Gymnastics Federation (FIG) convened a committee to review the current literature and address four questions: (1) Is there a negative effect of training on attained adult stature? (2) Is there a negative effect of training on growth of body segments? (3) Does training attenuate pubertal growth and maturation, specifically, the rate of growth and/or the timing and tempo of maturation? (4) Does training negatively influence the endocrine system, specifically hormones related to growth and pubertal maturation? The basic information for the review was derived from the active involvement of committee members in research on normal variation and clinical aspects of growth and maturation, and on the growth and maturation of artistic gymnasts and other youth athletes. The committee was thus thoroughly familiar with the literature on growth and maturation in general and of gymnasts and young athletes. Relevant data were more available for females than males. Youth who persisted in the sport were a highly select sample, who tended to be shorter for chronological age but who had appropriate weight-for-height. Data for secondary sex characteristics, skeletal age and age at peak height velocity indicated later maturation, but the maturity status of gymnasts overlapped the normal range of variability observed in the general population. Gymnasts as a group demonstrated a pattern of growth and maturation similar to that observed among short-, normal-, late-maturing individuals who were not athletes. Evidence for endocrine changes in gymnasts was inadequate for inferences relative to potential training effects. Allowing for noted limitations, the following conclusions were deemed acceptable: (1) Adult height or near adult height of female and male artistic gymnasts is not compromised by intensive gymnastics training. (2) Gymnastics training does not appear to attenuate growth of upper (sitting height) or lower (legs) body segment lengths. (3) Gymnastics training does not appear to attenuate pubertal growth and maturation, neither rate of growth nor the timing and tempo of the growth spurt. (4) Available data are inadequate to address the issue of intensive gymnastics training and alterations within the endocrine system.

Prediction of adult height by Tanner-Whitehouse method in young Caucasian male athletes

BACKGROUND

Although the accuracy of final height prediction using skeletal age development has been confirmed in many studies for children treated for congenital primary hypothyroidism, short normal children, constitutionally tall children, no studies compared the predicted adult height at young age with final stature in athletic population.

AIM

In this study, the intention was to investigate to what extent the Tanner-Whitehouse (TW) method is adequate for prediction of final stature in young Caucasian male athletes.

DESIGN

Prospective observational study.

METHODS

Plain radiographs of the left hand and wrist were obtained from 477 athletic children (ranging in age from 8.0 to 17.9 years) who came to the outpatient clinic between 2000 and 2011 for adult height estimation, with no orthopedic trauma suspected. Adult height was estimated using bone age rates according to TW method. Height was measured both at baseline and follow-up (at the age of 19 years).

RESULTS

No significant difference was found between the estimated adult height (184.9 ± 9.7 cm) and final stature (185.6 ± 9.6 cm) [95% confidence interval (CI) 1.61-3.01, P = 0.55]. The relationship between estimated and final adult height was high (r = 0.96). Bland-Altman analysis confirmed that the 95% of differences between estimated adult height and final stature lie between limits of agreement (mean ± 2 SD) (-5.84 and 4.52 cm).

CONCLUSION

TW method is an accurate method of predicting adult height in male normal-growing athletic boys.

An approach to constitutional delay of growth and puberty

Constitutional delay of growth and puberty is a transient state of hypogonadotropic hypogonadism associated with prolongation of childhood phase of growth, delayed skeletal maturation, delayed and attenuated pubertal growth spurt, and relatively low insulin-like growth factor-1 secretion. In a considerable number of cases, the final adult height (Ht) does not reach the mid-parental or the predicted adult Ht for the individual, with some degree of disproportionately short trunk. In the pre-pubertal male, testosterone (T) replacement therapy can be used to induce pubertal development, accelerate growth and relieve the psychosocial complaints of the adolescents. However, some issues in the management are still unresolved. These include type, optimal timing, dose and duration of sex steroid treatment and the possible use of adjunctive or alternate therapy including: oxandrolone, aromatase inhibitors and human growth hormone.

Bone age assessment by dual-energy X-ray absorptiometry in children: an alternative for X-ray?

OBJECTIVE

The aim of the study was to validate dual-energy X-ray absorptiometry (DXA) as a method to assess bone age in children.

METHODS

Paired dual-energy X-ray absorptiometry (DXA) scans and X-rays of the left hand were performed in 95 children who attended the paediatric endocrinology outpatient clinic of University Hospital Rotterdam, the Netherlands. We compared bone age assessments by DXA scan with those performed by X-ray. Bone age assessment was performed by two blinded observers according to the reference method of Greulich and Pyle. Intra-observer and interobserver reproducibility were investigated using the intraclass correlation coefficient (ICC), and agreement was tested using Bland and Altman plots.

RESULTS

The intra-observer ICCs for both observers were 0.997 and 0.991 for X-ray and 0.993 and 0.987 for DXA assessments. The interobserver ICC was 0.993 and 0.991 for X-ray and DXA assessments, respectively. The mean difference between bone age assessed by X-ray and DXA was 0.11 years. The limits of agreement ranged from -0.82 to 1.05 years, which means that 95% of all differences between the methods were covered by this range.

CONCLUSIONS

Results of bone age assessment by DXA scan are similar to those obtained by X-ray. The DXA method seems to be an alternative for assessing bone age in a paediatric hospital-based population.

Managing idiopathic short stature: role of somatropin (rDNA origin) for injection

Idiopathic short stature (ISS) is a term that describes short stature in children who do not have growth hormone (GH) deficiency and in whom the etiology of the short stature is not identified. Between 1985 and 2000, more than 40 studies were published regarding GH therapy for ISS. Only 12 of these had data to adult height, of which only 4 were controlled studies. A subsequent placebo-controlled study that followed subjects to adult height indicated that there was a gain of 3.7–7.5 cm in height with GH treatment. In 2003, the US Federal Drug Administration (FDA) approved GH for treatment of short stature. Even before FDA approval, patients with ISS made up about 20% of patients in GH databases, which is largely unchanged since FDA approval. There remains some controversy as to whether GH should be used to treat ISS. This controversy centers on the fact that there has been no definitive demonstration that short stature results in a disadvantage or problems with psychological adjustment, and thus, no demonstration that GH therapy results in improvement in quality of life.

Growth and early onset inflammatory bowel disease

In pediatrics, growth is considered one of the most important markers of overall well-being. This study looked at growth in children diagnosed with inflammatory bowel disease before they were 5 years old from a single center. The Children's Inflammatory Bowel Disease Center at Mount Sinai maintains a database of 1,150 children followed at the center. Ninety-three children were included in this study, 58% boys and 42% girls. The average age at diagnosis was 3.2 years. Sixty-two percent had ulcerative colitis and 38% had Crohn disease. Height was recorded at initial presentation and at the most recent visit to the center; from this, a height percentile and z score were calculated. A target adult height was calculated for each child on the basis of mid-parental height. This target height was compared to the actual height the children achieved or the percentile they were growing along. Ten percent of children in the study presented with growth failure. For children with early onset ulcerative colitis, 58% achieved or exceeded their projected height percentile. For children with early onset Crohn disease, 38% achieved or exceeded their projected height percentile. Fifty-nine percent of the entire group either maintained their presentation percentile or increased their height percentiles over time, with an increase in z score ranging from 0.093 to 4.137.

Idiopathic short stature: definition, epidemiology, and diagnostic evaluation

Idiopathic short stature is a condition in which the height of the individual is more than 2 SD below the corresponding mean height for a given age, sex and population, in whom no identifiable disorder is present. It can be subcategorized into familial and non-familial ISS, and according to pubertal delay. It should be differentiated from dysmorphic syndromes, skeletal dysplasias, short stature secondary to a small birth size (small for gestational age, SGA), and systemic and endocrine diseases. ISS is the diagnostic group that remains after excluding known conditions in short children.

Idiopathic short stature: management and growth hormone treatment

In the management of ISS auxological, biochemical, psychosocial and ethical elements have to be considered. In boys with constitutional delay of growth and puberty androgens are effective in increasing height and sexual characteristics, but adult height is unchanged. GH therapy is efficacious in increasing height velocity and adult height, but the inter-individual variation is considerable. The effect on psychosocial status is uncertain. Factors affecting final height gain include GH dose, height deficit in comparison to midparental height, age and first year height velocity. In case of a low predicted adult height at the onset of puberty, addition of a GnRH analogue can be considered. Although GH therapy appears safe, long-term monitoring is recommended.

Anastrozole increases predicted adult height of short adolescent males treated with growth hormone: a randomized, placebo-controlled, multicenter trial for one to three years

CONTEXT

The process of epiphyseal fusion during puberty is regulated by estrogen, even in males.

OBJECTIVE

Our objective was to investigate whether anastrozole, a potent aromatase inhibitor, could delay bone age acceleration and increase predicted adult height in adolescent boys with GH deficiency.

METHODS

Fifty-two adolescent males with GH deficiency treated with GH were randomized to cotreatment with anastrozole or placebo daily for up to 36 months.

RESULTS

Fifty subjects completed 12 months, 41 completed 24 months, and 28 completed 36 months. Linear growth was comparable between groups; however, there was a significantly slower increase in bone age advancement from baseline in the anastrozole group vs. placebo group after 2 yr (+1.8+/-0.1 vs. +2.7+/-0.1 yr, P<0.0001) and after 3 yr (+2.5+/-0.2 vs. +4.1+/-0.1 yr, P<0.0001). This resulted in a net increase in predicted adult height of +4.5+/-1.2 cm in the anastrozole group at 24 months and +6.7+/-1.4 cm at 36 months as compared with a 1-cm gain at both time points in the placebo group. Estradiol and estrone concentrations increased less in the anastrozole group compared with placebo group. All boys on the aromatase inhibitor had normal tempo of virilization. Safety data, including glucose, and plasma lipid concentrations were comparable between groups.

CONCLUSIONS

Anastrozole increases adult height potential of adolescent boys on GH therapy while maintaining normal pubertal progression after 2-3 yr. This treatment offers an alternative in promoting growth in GH-deficient boys in puberty. Long-term follow up is needed to elucidate fully the safety and efficacy of this approach.

Progressive reduction of relative height in childhood predicts adult stature below target height in boys with constitutional delay of growth and puberty

BACKGROUND/AIMS

In some adolescents with constitutional delay of growth and puberty (CDGP), the reduction in relative height (height SDs) starts already in childhood, before puberty. Some subjects with CDGP do not reach their target height (TH). We investigated whether early height SD reduction or testosterone treatment in low doses (1-2 mg/kg/month) influence final height (FH).

METHODS

The growth of 70 adult men with a history of CDGP was investigated. 31 subjects (13 treated with testosterone) had progressive height SD reduction between 3 and 9 years, and in 39 (17 treated with testosterone) no such reduction was seen.

RESULTS

In untreated subjects without early height SD reduction, FH was closer to TH than in those with such reduction (FH - TH 0.05 +/- 0.94 vs. -0.63 +/- 0.50 SD, p = 0.009). FH - TH did not differ between the testosterone-treated and untreated subjects in the group with early height SD reduction (FH - TH -0.36 +/- 0.48 vs. -0.63 +/- 0.50 SD, p = 0.15), nor in the group without such reduction (FH - TH -0.08 +/- 0.70 vs. 0.05 +/- 0.94 SD, p = 0.64).

CONCLUSION

Subjects with early height SD reduction do not attain FH consistent with their genetic height potential, whereas those without such reduction do. Treatment with low doses of testosterone does not adversely affect FH.

Growth hormone treatment of non-growth hormone-deficient growth disorders

Although a large body of data on efficacy and safety of growth hormone (GH) treatment for various non-growth hormone-deficient (GHD) growth disorders has accumulated from a combination of clinical trial and postmarketing sources in the last 20 years or more, there remain limitations. Clinical trial data have the advantage of direct comparison of well-matched, randomized patient groups receiving treatment (or not) under comparable conditions and, as such, provide the highest quality evidence of efficacy. Clinical trials, however, are typically too small for any statistically valid assessment for safety, which is more comprehensively addressed using postmarketing data. Consequently, while the efficacy of GH treatment in children with non-GHD growth disorders has been solidly established and, based on the combination of the rigor of the clinical trial data and numerical power of the postmarketing data, no major concerns exist regarding safety, additional long-term data are required.

Age at Growth Hormone Therapy Start and First-Year Responsiveness to Growth Hormone Are Major Determinants of Height Outcome in Idiopathic Short Stature

AIM

To develop methods to identify factors associated with a favorable outcome in GH-treated children with idiopathic short stature (ISS).

METHODS

From 4,685 children listed as having ISS within KIGS (Pfizer International Growth Database), we studied (a) the prediction model group (n = 657) to develop the first-year prediction model, and (b) the near adult height group (NAH; n = 256) which received GH for >4 years to develop descriptive models for adult height and overall height gain.

RESULTS

NAH group at GH start: age was 10.0 years, height -2.5 SD score (SDS), weight -2.3 SDS, height minus mid-parental height (MPH) -1.5 SDS; GH dose 0.19 mg/kg/week. Height gain was 1.1 SDS at a median age of 17.2 years. Growth response correlated positively with GH dose and weight at the start of GH treatment, and negatively with age and height SDS minus MPH SDS. The model explains 39% (error SD 1.2 cm) of the variability. Adult height correlated (R(2) = 0.64) positively with height at GH start, MPH and the first-year responsiveness to GH, and negatively with age.

CONCLUSIONS

Prepubertal children with ISS who show an appropriate first-year response to GH are likely to benefit from long-term treatment, even on low GH dosages.

Maturity offset in gymnasts: application of a prediction equation

PURPOSE

To verify the applicability of the prediction equation for maturity offset in a sample of female gymnasts followed longitudinally through adolescence.

METHODS

Fifteen gymnasts were followed longitudinally for 6-7 yr across adolescence. Weight, height, and sitting height were measured at annual intervals. The Preece-Baines Model I was fitted to longitudinal height data for individual gymnasts to derive age at peak height velocity (PHV). The curve-fitting protocol was successfully fit to the height records of 13 of the 15 gymnasts with standard errors of estimate between 0.02 and 0.28 cm. Maturity offset was calculated from measurements taken at each observation for the 13 gymnasts and also added to chronological age at each observation point to provide an estimated age at PHV. Age at PHV derived with the Preece-Baines model was used as the criterion. Differences between the criterion age at PHV and predicted age at PHV were calculated.

RESULTS

Maturity offset overestimates age at PHV in gymnasts. Mean predicted ages at PHV deviate linearly from the criterion age at PHV, but the difference is significant only at 9 yr. Correlations between maturity offset predicted ages at PHV and criterion age at PHV range from -0.13 to +0.76. The Bland-Altman plot of criterion and predicted ages at PHV suggest a systematic bias in the predictions.

CONCLUSION

Maturity offset appears to have limitations when applied to female gymnasts. Care is warranted in utilizing maturity offset per se and predicted age at PHV based on maturity offset as an indicator of maturity timing in female gymnasts and perhaps other short females.

Impact of body mass index on growth in boys with delayed puberty

It is unclear whether overweight but otherwise healthy boys with delayed puberty have a variation of constitutional delay of growth and maturation (CDGM) or a different etiology for their pubertal delay. To characterize better this group of boys and investigate whether their growth pattern distinguishes them from boys with typical CDGM, growth data were analyzed in eight overweight (BMI SDS > or = 85th percentile) and 37 non-overweight (BMI SDS <85th percentile) boys with delayed puberty. Primary outcome measures included predicted height (PH) and adult height (AH). At diagnosis of delayed puberty, the overweight boys had less delayed bone ages (chronological age [CA] - bone age [BA] = 1.2 +/- 1.0 vs 2.5 +/- 1.1 years, p <0.01), greater height SDS for CA (-0.5 +/- 0.7 vs -2.4 +/- 0.8, p <0.001), and greater height SDS for BA (0.6 +/- 0.9 vs -0.4 +/- 1.1, p <0.05). PH for the overweight boys exceeded their mid-parental height (MPH) by 5.0 +/- 7.2 cm while non-overweight boys were predicted to fall below their MPH by 2.8 +/- 6.3 cm (p <0.01). Available AH data corroborated the differences in PH, with a trend for overweight boys to have greater height relative to their MPH than the non-overweight boys. These observations suggest that in the context of delayed puberty, being overweight may modulate adult height and/or that the etiology of delayed puberty in overweight boys may differ from typical CDGM.

Are short boys with constitutional delay of growth and puberty candidates for rGH therapy according to FDA recommendations?

BACKGROUND/AIMS

According to FDA-approved guidelines, boys whose height predictions fall to 160 cm or less are considered for treatment with recombinant growth hormone (rGH). The aim of this study was to analyze the value of different height prediction methods by accurately identifying those boys with constitutional delay of growth and puberty (CDGP) in whom final height (FH) prognosis was poor (<or=160 cm) and who might therefore be candidates for this treatment modality.

METHODS

In 69 boys with CDGP diagnosed at a mean age of 14.9 +/-1.2 years, FH prediction was calculated by means of Bayley-Pinneau (BP), Roche-Wainer-Tissen (RWT), Tanner-Whitehouse II (TWII) and target height (TH) methods. At the age of 22.6 +/- 3.5 years their height was remeasured and the accuracy of height prediction was analyzed.

RESULTS

In 6 men (8.7%) measured FH was <or=160 cm. Depending on the prediction method, different individual patients within the 14- to 16-year age range would have been candidates for rGH treatment. The BP method would have recruited 8 subjects of whom only 3 had FH <or=160 cm (sensitivity 50%, specificity 92%). The RWT and TW II methods identified only one recruit, and this patient did achieve FH <or=160 cm (sensitivity 17%, specificity 100%). None of the 8 subjects with FH <or=160 cm would have qualified for GH treatment using the TH method. In three boys none of the four methods predicted their final height <or=160 cm.

CONCLUSION

Although some boys with CDGP may be considered the candidates for rGH treatment according to FDA recommendations, none of the available methods of prediction are sufficiently sensitive to reliably recruit 14- to 16-year-old boys whose final height will fall at or below 160 cm.

Idiopathic short stature

The diagnostic term, idiopathic short stature, has emerged over the past 30 years and refers to children with short stature of unknown etiology. Controversy exists regarding the scope of the diagnosis and options for its treatment. This article reviews origins of the diagnosis idiopathic short stature and current diagnostic criteria, scientific advances in delineating etiologies of idiopathic short stature, management options, and implications of management decisions for child health.

Development and testing of multilevel models for longitudinal craniofacial growth prediction

INTRODUCTION

The aims of this study were to (1) develop longitudinal growth curves that would allow individual variations to be accurately modeled and (2) use these models to predict craniofacial growth changes in children with varying amounts of longitudinal data available.

METHODS

Based on a sample of 159 girls (994 cephalograms) and 128 boys (947 cephalograms), multilevel population models were derived. Polynomial models of the population's growth curve were derived for the measurements MPA, Me-X, Me-theta, Me-Y, and Me-R. Angular and horizontal measures (MPA, Me-X, and Me-theta) were described by simpler, second-order models, and vertical measures (Me-Y and Me-R) were described by more complex, fifth-order models.

RESULTS

Decreases in MPA during childhood and increases in Me-theta during adolescence could be explained by the relative contributions of the horizontal (Me-X) and vertical (Me-Y) movements of menton. There was greater anterior movement of menton during childhood and greater inferior movement during the adolescent growth spurt. By using varying numbers of longitudinal cephalograms between 6 and 10 years of age, the models were used to predict subjects' craniofacial growth changes from ages 10 to 15. Based on correlations, root mean squared error, and percent accuracy, individual growth predictions for the various measures were found to be highly accurate on an independent subsample drawn from the larger sample and on an independent validation sample. Correlations between predicted and actual values on the sample used to develop the models ranged from 0.81 to 0.95. Accuracy was best for the measurements that changed the most during the prediction period (Me-Y and Me-R), with accuracies between 83% and 90%. More longitudinal data did not increase the predictive accuracy for all measurements. The models that were least accurate (Me-X, MPA, and Me-theta) showed the greatest improvement in prediction accuracy with more longitudinal data. These improvements ranged from 1.6% to 15%.

CONCLUSIONS

Longitudinal growth curves based on multilevel procedures can accurately describe population and individual growth curves, and 5-year predictions with this method are highly accurate and externally valid.

Final height in patients with constitutional delay of growth and development from tall statured families

Constitutional delay of growth and development occurs not only in children of short statured families but also in children of tall statured families. We represent the final height from 12 boys and 21 girls cared for CDGD. The mean target height for boys was 186.6 cm and for girls 173.6 cm and final heights were 191.2 and 176.9 cm, respectively. The final height of 14 patients exceeded the mean target height by more than 4 cm, nine patients exceeded the familial target height range. Only one boy did not reach the familial target height range. We conclude that CDGD occurs in equal quantities in boys and in girls irrespective of the familial height score and will lead to normal final heights within the familial target height range. In general, no therapy is necessary to alter the progression of CDGD.

Constitutional delay of growth and puberty: from presentation to final height

This retrospective study evaluated clinical characteristics of patients with constitutional delay of growth and puberty (CDGP) at presentation, during puberty and at final height. The records of 151 children (105 boys, 46 girls) with CDGP were reviewed and the results were evaluated with respect to findings in healthy Turkish schoolchildren. CDGP was twice as frequent in boys as in girls. Height and weight deficit and short sitting height of the children were evident at presentation and continued up to final height. Mean age of onset of puberty was retarded by 2.5 years in girls and by 3 years in boys. The time between onset of puberty and pubertal growth spurt was shorter in both girls and boys than in the controls. Peak growth velocity was compromised in both girls and boys. Forty-one patients (30 boys, 11 girls) reached final height (FH). Mean FH was shorter than both target height and predicted adult height. The Bayley-Pinneau method was found to be a better predictor of FH than either the Tanner-Whitehouse method or target height. FH also showed correlation with the father's height. There was no effect of testosterone treatment on final height. Height deficit at onset of puberty, shorter duration between onset of puberty and pubertal growth spurt, compromised peak growth velocity and short upper segment due to delayed puberty, are findings which may explain the decreased final height of children with CDGP.

Growth hormone (GH) treatment to final height in children with idiopathic short stature: evidence for a dose effect

OBJECTIVES

To investigate in an open-label randomized study, the effect of two doses of growth hormone (GH) on final height and height velocity during the first 2 years of treatment of children with idiopathic short stature (mean baseline height standard deviation score [SDS] -3.2).

STUDY DESIGN

Patients were treated with GH at 0.24 mg/kg/week, 0.24 mg/kg/week for the first year and at 0.37 mg/kg/week thereafter (0.24-->0.37), or 0.37 mg/kg/week. Final height was evaluated in 50 patients at study completion (mean treatment duration, 6.5 years).

RESULTS

Patients who received 0.37 mg/kg/week (n = 72) experienced a significantly greater increase in height velocity than those who received 0.24 mg/kg/week (n = 70) (treatment difference = 0.8 cm/year; P = .003) or 0.24-->0.37 mg/kg/week (n = 67) (treatment difference = 0.9 cm/year; P = .001). For the 50 patients for whom final height measurements were available, mean height SDS increased by 1.55, 1.52, and 1.85 SDS, respectively, for the three dose groups. For the primary comparison between the 0.37 mg/kg/week and 0.24 mg/kg/week dose groups, the mean treatment difference (adjusted for differences in baseline predicted height SDS) was 0.57 SDS (3.6 cm; P = .025). Mean overall height gains (final height minus baseline predicted height) were 7.2 cm and 5.4 cm for the 0.37 mg/kg/week and 0.24 mg/kg/week dose groups, respectively, without dose effects on safety parameters. Final height measurements were within the normal adult height range for 94% of patients randomized to 0.37 mg/kg/week who continued to final height.

CONCLUSION

GH treatment dose-dependently increases height velocity and final height in children with idiopathic short stature.

Comparison of final heights of growth hormone-treated vs. untreated children with idiopathic growth failure

We measured adult heights (Ht) of 94 healthy GH-sufficient children (peak GH > 10 ng/mL, polyclonal RIA) whose Ht at presentation were more than 2 SD below the mean for chronological age, with normal weight-to-Ht ratios, normal body proportions, and pathologic growth velocity for chronological age. Group 1 (n 36, 6 females) received standardized doses (0.3 mg/kg x week) of GH (mean duration = 41 months), while group 2 (n = 58, 17 females) received no treatment. Our conclusion was that the mean final Ht SD score in the GH-treated group (-1.5) was significantly greater than in the untreated group (-2.1); P < .001. Genetic predisposition to short stature was evident in both groups: the midparental Ht SD score was -1.1 in the treated and -1.0 in the untreated group. Midparental Ht was met or exceeded by 42% of the GH-treated group but only 15% of the untreated group. Final Ht was not significantly different from predicted Ht, except from GH-treated girls, who exceeded their predicted Ht. Although the mean Ht gains (6.8 cm in girls and 3 cm in boys) were modest and variable, GH treatment provided significantly better Ht outcomes for the majority of children with idiopathic growth failure.

Final height prediction models for pubertal boys

Accurate adult height prediction is of clinical importance in assessing the need for pharmacological intervention and in the evaluation of the outcome of therapy. The methods currently in use are subject to a wide range of error, one source of which is the use of bone age (BA) measurements. We have developed a computer model for predicting adult height in pubertal boys without using BA determinations. The model is based on the existing Infancy-Childhood-Puberty model and calculates the onset of the pubertal growth spurt. Predicted adult height was assessed using this new model and four others in a group of normal boys and in a group of short normal boys receiving growth hormone. Calculated final heights by all the methods were not significantly different. Incorporation of paternal height into the prediction equations increased the accuracy of the prediction. It was concluded that our new model is as accurate as existing methods of predicting final height that involve assessing BA.

Growth hormone therapy in children with short stature: is bigger better or achievable?

The introduction of recombinant DNA-synthesized human growth hormone in the mid-1980s, and its attendant unlimited supply, have led to wider application of growth hormone therapy in children. Over the past decade, the efficacy of growth hormone treatment in patients with Turner syndrome and chronic renal insufficiency, two conditions in which growth hormone secretion is normal, in improving growth velocity and final height, has also led to the consideration of growth hormone therapy in children with idiopathic short stature. Although thousands of patients with idiopathic short stature are currently being treated with growth hormone, the limited overall results available at this time do not show a significant improvement in final adult height despite an improvement in short-term growth velocity. Potential reasons for this outcome include 1) skeletal age advancing more rapidly than height age, 2) heterogeneity of the patient population comprising idiopathic short stature, 3) inherent inaccuracies of methodological tools, such as measurement of predicted adult height, and 4) a subset of children with idiopathic short stature who may, in fact, have partial growth hormone insensitivity. From a psychological perspective, the consensus of investigations in non-clinic-referred populations of psychosocial function in children with short stature do not indicate a disadvantage compared with children of normal height when socio-economic status is taken into consideration. These results, in conjunction with the minimal gains reported in behavioural measurements in idiopathic short children treated with growth hormone, question the traditional rationale that augmentation of growth velocity results in improvement in psychosocial well-being.

Final height outcome in both untreated and testosterone-treated boys with constitutional delay of growth and puberty

The present retrospective study is based on a historical follow-up of 49 boys with constitutional delay of growth and puberty (CDGP) who went into puberty spontaneously (27 cases) or induced by depotestosterone treatment, 50 mg/ month for 6 months (22 cases). At the time of puberty the two groups of boys were similar in bone age, height deficiency, target height (TH) and had similar predicted final heights (FH). Their FH was measured and compared with TH calculated from measured parents' heights. FH did not significantly differ between the untreated boys and those treated. In the two groups of patients FH was similar and corresponded to both TH and height predicted at puberty onset. This study confirms that most boys with CDGP spontaneously attain a FH within the target range (24/27 cases). A short-term and low dose course of depotestosterone can be used without adverse effects on FH. The Bayley-Pinneau method can be generally considered accurate for predicting FH in CDGP, although significant discrepancies between FH and predicted height have been recorded in a fair number of both untreated and treated boys.

Spontaneous growth in idiopathic short stature. European Study Group

Documenting the spontaneous growth pattern of children with idiopathic short stature (ISS) should be helpful in evaluating the effects of growth promoting treatments. Growth curves for children with ISS were constructed, based on 229 untreated children (145 boys and 84 girls) from nine European countries. The children were subdivided according to target range and onset of puberty, and the growth of these subgroups was evaluated from standard deviation scores (SDS). At birth, children with ISS were already shorter than normal (means; boys -0.8 SDS, girls -1.3 SDS). Height slowly decreased from -1.7 SDS at the age of 2 years to -2.7 SDS at the age of 16 years in boys and 13 years in girls. Final height was -1.5 SDS in boys and -1.6 SDS in girls (mean (SD): boys 164.8 (6.1) cm, girls 152.7 (5.3) cm)), which was 5-6 cm below their target height. The onset of puberty was delayed (boys 13.8 (1.3) years, girls 12.9 (1.1) years). Subclassification resulted in similar growth curves. These specific growth data may be more suitable for evaluating the effects of growth promoting treatments than population based references.

Spontaneous growth and response to growth hormone treatment in children with growth hormone deficiency and idiopathic short stature

Isolated idiopathic growth hormone deficiency (GHD) and idiopathic short stature (ISS) can be difficult to distinguish, but the therapeutical consequences are different. In this report the data on final height of untreated and treated children with GHD and ISS are reviewed. Untreated GH-deficient individuals who underwent spontaneous puberty (22 male, 14 female patients) reached a mean final height of 4.7 SD (range 3.9 to 6.0) below the population's mean. If puberty was induced (19 male patients), mean final height SD score (SDS) was -3.1. Traditional regimens of GH administration (2-4 injections/wk) in 236 children (184 boys, 52 girls) with GHD and spontaneous puberty resulted in a final height SDS of -2.8 (range -1.5 to -4.7). In 190 children in whom puberty was induced (139 boys, 51 girls) mean final height was -1.6 (range - -1.1 to -2.4). The mean gain in final height SDS is therefore estimated at 1.5-2.0 in average cases, and 3.5 in extreme cases. Preliminary data suggest that on present regimens mean final height may approach target height. In untreated boys with ISS the mean final height was 2-5 cm lower than that predicted before puberty, whereas in girls it was almost equal to the prediction. After GH treatment the mean final height was 0.4-3.0 cm higher than the predicted adult height, which results in an average net gain in final height SDS of approximately 0.5-0.8 (3-5 cm).