The effects of growth hormone treatment on bone mineral density and body composition in girls with turner syndrome

BACKGROUND: Many girls with Turner syndrome (TS) are treated with GH to increase adult height. In addition to promoting longitudinal bone growth, GH has effects on bone and body composition. OBJECTIVE: The objective was to determine how GH treatment affects bone mineral density (BMD) and body composition in girls with TS. METHOD: In a cross-sectional study, we compared measures of body composition and BMD by dual energy x-ray absorptiometry, and phalangeal cortical thickness by hand radiography in 28 girls with TS who had never received GH and 39 girls who were treated with GH for at least 1 yr. All girls were participants in a National Institutes of Health (NIH) Clinical Research Center (CRC) protocol between 2001 and 2006. RESULTS: The two groups were similar in age (12.3 yr, sd 2.9), bone age (11.5 yr, sd 2.6), and weight (42.8 kg, sd 16.6); but the GH-treated group was taller (134 vs. 137 cm, P = 0.001). The average duration of GH treatment was 4.2 (sd 3.2) yr (range 1-14 yr). After adjustment for size and bone age, there were no significant differences in BMD at L1-L4, 1/3 radius or cortical bone thickness measured at the second metacarpal. However, lean body mass percent was higher (P < 0.001), whereas body fat percent was lower (P < 0.001) in the GH-treated group. These effects were independent of estrogen exposure and were still apparent in girls that had finished GH treatment at least 1 yr previously. CONCLUSIONS: Although GH treatment has little effect on cortical or trabecular BMD in girls with TS, it is associated with increased lean body mass and reduced adiposity.     

Growth hormone therapy and bone mineral density in Turner syndrome

In a previous report, preliminary data showed a significant reduction in cortical bone mineral density (BMD) in women with Turner syndrome that had been treated with GH compared with women with Turner syndrome that had not been treated. To clarify this point, we have investigated the effects of GH treatment at multiple sites in this case-control, cross-sectional study. There were 23 women per group, who were similar in age, height, body mass index, estrogen use, and ethnic makeup. Median age (range) at start and duration of GH treatment was 9 (3-17) and 5 (2-9) yr, respectively. GH-treated women had a slightly greater ( approximately 8%, P = 0.03) width of the radial shaft, but otherwise there were no significant differences between groups in bone dimensions or BMD at the distal radius, lumbar spine, or femoral neck. Furthermore, regression analysis in a linear model including independent variables of age, age at diagnosis, body mass index, presence of spontaneous puberty, and GH use confirmed that GH use did not contribute to variation in BMD.     

A longitudinal study on bone mineral density until adulthood in girls with Turner's syndrome participating in a growth hormone injection frequency-response trial

OBJECTIVE: The aim of this study was to assess the volumetric bone mineral density (BMD) in girls with Turner's syndrome (TS) before and during growth hormone (GH) treatment in combination with low dose oestrogens as well as three years after discontinuation of GH treatment. DESIGN: In a prospective, randomized injection frequency-response study, the effect of GH treatment in combination with low dose ethinyl oestradiol (starting with 0.05 microgram/kg/day), on BMD was evaluated, comparing twice daily (BID) with once daily (OD) injections of a total GH dose of 6 IU/m2/day until adult height was reached. After discontinuation of GH treatment, the dosage of oestrogens was further increased to adult supplementation levels. PATIENTS: Nineteen untreated girls with TS, mean (SD) baseline pretreatment age 13.3 (1.7) (range 11.0-17.6) year. MEASUREMENTS: Before and during GH treatment, measurements of volumetric BMD were performed using phalangeal radiographic absorptiometry. In addition, the BMD measurements were repeated three years after discontinuation of GH treatment. BMD results were adjusted for bone age and sex, and expressed as SD-scores (SDS) using reference values of healthy Dutch girls. RESULTS: At baseline, most individual BMD values of cortical bone as well as those of trabecular bone were within the normal range of healthy girls. However, the mean BMD SDS of the trabecular bone was significantly lower than zero. During treatment, the BMD SDS showed a significant increment to values equal or higher than zero after mean (SD) GH treatment period of 36.6 (7.5) months. The increase in BMD of the cortical bone was significantly higher in the OD group than in the BID group. The BMD SDS in the last year of GH treatment was not significant different between the two injection frequency groups. Three years after discontinuation of GH treatment, the BMD values had increased further similar as in healthy girls, resulting in BMD values all within normal range or even higher. CONCLUSIONS: Most untreated girls with Turner syndrome, age >/= 11 years, have a normal volumetric BMD of the cortical, as well as of the trabecular bone compared to healthy girls. During GH treatment with 6 IU/m2/day in combination with low dose oestrogens, the BMD SDS increases significantly. After discontinuation of GH treatment and the use of oestrogens in an adult dosage, the BMD was as high as in young healthy women.     

Body proportions during long-term growth hormone treatment in girls with Turner syndrome participating in a randomized dose-response trial

To assess body proportions in girls with Turner syndrome (TS) during long term GH treatment, height, sitting height (SH), hand (Hand) and foot (Foot) lengths, and biacromial (Biac) and biiliacal (Biil) diameters were measured in 68 girls with TS participating in a GH dose-response trial. These previously untreated girls with TS, aged 2-11 yr, were randomly assigned to 1 of 3 GH dosage groups: group A, 4 IU/m2 x day; group B, first year 4 and thereafter 6 IU/m2 x day; group C, first year 4, second year 6, and thereafter 8 IU/m2 x day. Seven-year data were evaluated to assess the effect of GH treatment on body proportions during childhood. In addition, data from all girls who had reached adult height were evaluated to determine the effect on the adult body proportions. All results were adjusted for age and sex and expressed as SD scores using reference values of healthy Dutch girls. To describe the proportions of SH, Hand, Foot, Biac, and Biil to height, these values were adjusted for the SD score of height and were expressed as shape values, using the formula, e.g. for SH: shape SH = (SH SD score - height SD score)/square root(2 - 2 x correlation coefficient between SH and height in the reference population). Furthermore, SD scores using references of untreated girls with TS were calculated for height and SH. Values less than -2 or more than +2 were considered outside the normal range. At baseline, the shape values of all measurements were significantly higher than zero, but most mean shape values were still within the normal range. Seven-year data of 64 girls and adult height data of 32 girls showed that an increase in height was accompanied by an even higher increase in Foot, resulting in mean SD scores above zero and shape values of +2 and higher. The increase in the shape value of Foot was significantly higher in groups B and C compared to that in group A after 7 yr of GH treatment, but there were no significant differences between the GH dosage groups in the girls who had reached adult height. The shape values of SH had decreased to values closer to zero after reaching adult height, especially in group A. A similar pattern in the relationship of SH to height was seen using references of girls with TS. No significant changes in the other proportions were found after reaching adult height. In conclusion, on the average, untreated girls with TS have relatively large trunk, hands, and feet, and broad shoulders and pelvis compared to height. The increase in height after long term GH treatment is accompanied by an even higher increase in Foot and a moderate improvement of the disproportion between height and SH. Recently published reference data from untreated adults with TS and the results of a different patient group receiving a comparable GH dosage suggest that the disproportionate growth of feet has to be considered a part of the natural development in TS, but might be influenced by higher GH dosages. The development of large feet can play a role in the decision of the girl to discontinue GH treatment in the last phase of growth.     

Normalization of height in girls with Turner syndrome after long-term growth hormone treatment: results of a randomized dose-response trial

Short stature and ovarian failure are the main features in Turner syndrome (TS). To optimize GH and estrogen treatment, we studied 68 previously untreated girls with TS, age 2-11 yr, who were randomly assigned to one of three GH dosage groups: group A, 4 IU/m2 day (approximately 0.045 mg/kg x day); group B, first yr 4, thereafter 6 IU/m2 x day (approximately 0.0675 mg/kg/day); group C, first yr 4, second yr 6, thereafter 8 IU/m2 x day (approximately 0.090 mg/kg x day). In the first 4 yr of GH treatment, no estrogens for pubertal induction were given to the girls. Thereafter, girls started with 17beta-estradiol (5 microg/kg bw x day, orally) when they had reached the age of 12 yr. Subjects were followed up until attainment of adult height or until cessation of treatment because of satisfaction with the height achieved. Seven-year data of all girls were evaluated to compare the growth-promoting effects of three GH dosages during childhood. After 7 yr, 85% of the girls had reached a height within the normal range for healthy Dutch girls. The 7-yr increment in height SD-score was significantly higher in groups B and C than in group A. In addition, we evaluated the data of 32 of the 68 girls who had completed the trial after a mean duration of treatment of 7.3 yr (range, 5.0 - 8.75). Mean (SD) height was 158.8 cm (7.1), 161.0 cm (6.8), and 162.3 cm (6.1) in groups A, B, and C, respectively. The mean (SD) difference between predicted adult height before treatment and achieved height was 12.5 cm (2.1), 14.5 cm (4.0), and 16.0 cm (4.1) for groups A, B, and C, respectively, being significantly different between group A and group C. GH treatment was well tolerated in all three GH dosage groups. In conclusion, GH treatment starting in relatively young girls with TS results in normalization of height during childhood, as well as of adult height, in most of the individuals. With this GH and estrogen treatment regimen, most girls with TS can grow and develop much more in conformity with their healthy peers.     

The effect of short- and long-term growth hormone treatment on bone mineral density and bone metabolism of prepubertal children with idiopathic short stature: a 3-year study

OBJECTIVE: We recently reported that children with idiopathic short stature (ISS) have decreased lumbar spine bone mineral density (BMD) that increases after 1 year of GH therapy. The aim of this study was to confirm these short-term results and to evaluate the effect of long-term GH therapy on the BMD of children with ISS. PATIENTS AND DESIGN: We treated a group of 16 short, slow-growing but otherwise healthy non-GH-deficient prepubertal children (8 girls and 8 boys) with a chronological age of 9.5 +/- 0.9 years, a bone age of 8.1 +/- 1.2 years and a height of 124.3 +/- 6.3 cm (height-SDS of -2.1 +/- 0.6) with GH at a dose of 0.1 IU/kg/day for 3 consecutive years. MEASUREMENTS: Height was determined at 3-month intervals and annual growth velocities were calculated. Bone ages and BMD were measured every 12 months by dual-energy X-ray absorptiometry, as were serum concentrations of the carboxy-terminal propeptide of type 1 collagen (PICP) and the carboxy-terminal cross-linked telopeptide of type 1 collagen (ICPT). RESULTS: Growth velocity increased from 4.0 +/- 0.8 cm/year to 8.7 +/- 1.5 and 8.0 +/- 1.7 cm/year at 12 and 36 months of GH therapy, respectively, while height-SDS improved from -2.1 +/- 0.6 to -1.6 +/- 0.4 after 36 months of GH (P < 0.0001). Baseline lumbar spine BMD was decreased when compared to that of a control group of healthy children paired for gender, bone age and height (0.640 +/- 0.08 g/cm2vs. 0.730 +/- 0.08 g/cm2; P < 0.003). Lumbar spine BMD increased after 1 year of GH from 0.640 +/- 0.08 to 0.749 +/- 0.08 g/cm2 (P < 0.05), reaching levels similar to that of controls followed for 1 year without therapy (0.749 +/- 0.04 g/cm2vs. 0.760 +/- 0.08 g/cm2). During this period lumbar spine BMD increased 14.5% in the ISS subjects and 3.9% in the controls. Over the following 2 years of GH therapy the lumbar spine BMD of our ISS patients increased at a rate similar to that of the control population, so that after 3 years of consecutive GH therapy the lumbar spine BMD of ISS children was comparable to that of the controls (0.784 +/- 0.12 g/cm2vs. 0.785 +/- 0.09 g/cm2). Femoral neck BMD of our patients was similar to that of the controls at baseline and at 36 months. Following 1 year of GH treatment serum concentrations of PICP increased from 229.6 +/- 63.5 to 358.6 +/- 87.9 micro g/l, while levels of ICTP increased from 9.6 +/- 5.9 to 13.7 +/- 2.1 micro g/l. After 36 months of GH therapy, PICP and ICTP values had decreased to 303.3 +/- 67.2 micro g/l and 11.3 +/- 3.3 micro g/l, respectively, and were no longer significantly different from baseline. CONCLUSIONS: Children with ISS have decreased lumbar spine BMD, which normalized after 1 year of GH. Over the next 2 years of therapy lumbar spine BMD increased at a normal rate, so that after 3 consecutive years of GH the lumbar spine BMD of children with ISS was similar to that of controls. Bone turnover increased with treatment as indicated by a rise in bone formation and bone resorption markers.     

Bone geometry and volumetric bone mineral density in girls with Turner syndrome of different pubertal stages

Objective An increased rate of fractures has been reported in patients with Turner syndrome (TS). We aimed to assess bone geometry and volumetric bone mineral density (vBMD) at the radius in girls with TS and to evaluate the relationships between bone parameters and fracture history. Methods and design Sixty‐seven girls with TS aged 6–19 years treated currently or in the past with growth hormone (GH) and/or oestrogens were examined using peripheral quantitative computed tomography. Results were compared to reference data. Results Cortical area and cortical thickness were low in all age groups (all P < 0·001). Height‐adjusted total bone area at the diaphysis was increased in prepubertal and postpubertal girls (mean Z‐score 1·0, P < 0·05 for both) and normal in the pubertal group (mean Z‐score 0·1). Cortical vBMD was decreased (mean age‐specific Z‐scores ?2·0, ?1·6 and ?1·0 for prepubertal, pubertal and postpubertal groups, respectively, P < 0·01 for all groups). Height‐ , age‐ and cortical thickness‐adjusted cortical vBMD was positively correlated to the duration of GH therapy (P = 0·012) and to oestrogen administration (P = 0·047). Girls with a history of fractures had lower total vBMD at the metaphysis compared to nonfractured TS girls (mean Z‐scores ?1·7 vs?0·9, P = 0·04). Conclusions There is a cortical bone deficit in girls with TS characterized by low cortical area, thin cortex and probably decreased cortical vBMD. Early commencement of GH therapy, as well as oestrogen replacement, is associated with higher cortical vBMD. Further studies should investigate the potential causality of this relation.     

Early treatment with GH alone in Turner syndrome: prepubertal catch-up growth and waning effect

OBJECTIVE: In order to ascertain the advantages of early GH treatment in Turner syndrome (TS), we started a prospective study aimed at evaluating prepubertal height gain in a cohort of 29 girls who were treated with the same pro-kilo GH dose (1.0 IU/kg per week) since they were less than 6 years old and for at least 5 years before entering puberty. PATIENTS AND DESIGN: Following a minimum of 6 months of baseline observations, 29 girls with TS were enrolled for this prospective study provided that they (a) were less than 6 years old, (b) were below -1.0 standard deviation score (SDS) for height, (c) had a projected adult height (PAH) lower than the respective target height (TH) and (d) had a height velocity (HV) lower than -1.0 SDS. All the selected girls underwent a 5-year treatment with biosynthetic GH at a stable dose of 1.0 IU/kg per week and were periodically measured during the treatment period in order to evaluate height, HV and PAH. RESULTS: After a dramatic acceleration during the 1st year, HV was attenuated during the subsequent years, reaching its nadir at the 5th year. Height deficiency under therapy progressively decreased from entry onwards, shifting from -2.4+/-0.7 to -1.0+/-1.2 SDS. In the same period, mean PAH progressively increased, although after 5 years it remained lower than the average TH. CONCLUSIONS: (a) An effective growth-promoting strategy in TS should be based on early GH treatment, as suggested by our results. (b) This strategy could result in a prepubertal normalization of height, thus allowing the appropriate timing for the induction of puberty. (c) An initial GH dose of 1.0 IU/kg per week may be suitable during the first years of therapy, as shown by our data documenting an important waning effect of GH therapy only after the 4th year of treatment. (d) No acceleration of bone maturation was observed under this treatment regimen.     

Fracture risk and bone mineral density in Turner syndrome

Bone health is a major lifelong concern in caring for women and girls with Turner syndrome (TS). There is an approximately 25% increase in fracture risk most of which is related to medium or high impact trauma. The long bones, especially of the forearm are predominantly affected. This fact may be due to a selective cortical bone deficiency in TS which is unrelated to hypogonadism. In addition, lack of adequate estrogen replacement can lead to trabecular bone deficiency and increase in vertebral compression fractures after age 45. Evaluation of bone density by dual X-ray absorptiometry (DEXA) is important, however, it should be used judiciously in TS in view of its inherent tendency to underestimate the bone density of people with short stature. Bone size-independent methods, such as QCT or volumetric transformation of DEXA data should be used in individuals shorter than 150 cm. Achieving optimal bone density is of critical importance for fracture prevention in TS, and should be pursued by timely introduction of hormone replacement therapy, adequate dose of estrogens during the young adult life, optimal calcium and vitamin D intake and regular physical exercise. In addition, other measures to prevent fall and trauma should be considered, including optimizing hearing and vision, avoiding contact sports and exercise to improve coordination.     

Carbohydrate metabolism during growth hormone treatment and after discontinuation of growth hormone treatment in girls with Turner syndrome treated with once or twice daily growth hormone injections

OBJECTIVE: To assess possible side-effects of treatment with supraphysiological GH dosages on carbohydrate (CH) metabolism in girls with Turner syndrome (TS) during GH treatment until adult height is reached as well as after discontinuation of GH treatment. DESIGN: In a prospective, randomized injection frequency-response study, the effect of GH treatment in combination with low dose ethinyl oestradiol on CH metabolism was evaluated, comparing twice daily (BID) with once daily (OD) injections of a total GH dose of 6 U/m2/day until adult height was reached. PATIENTS: Nineteen untreated girls with TS, mean (SD) pretreatment age 13.3 (1.7) (range 11.0-17.6) year. MEASUREMENTS: Glucose and insulin concentrations during oral glucose tolerance tests (OGTT) were measured before and during GH treatment, as well as at 6 months after discontinuation of GH treatment. RESULTS: GH treatment was discontinued after a mean of 43 (range 27-57) months. In one of the 19 girls, a different girl at each time point before, during and after discontinuation of GH treatment, the glucose response to OGTT after 120 minutes was above 7.8 mmol/l but below 11.1 mmol/l, indicating impaired glucose tolerance. None of the girls developed diabetes mellitus. Fasting glucose levels did not significantly change during, or after discontinuation of GH treatment. The 3 h area under the curve for time-concentration adjusted for fasting levels during the OGTT for glucose showed a significant decrease during GH treatment. In contrast to the glucose levels, GH treatment induced considerably higher insulin levels compared to pretreatment values. After discontinuation of GH insulin levels decreased to values comparable with pretreatment levels. None of these observed changes were different between the GH injection frequency groups. The changes in CH variables during and after discontinuation of GH were not related to changes in body mass index. CONCLUSIONS: GH treatment with 6 U/m2/day in combination with low dose ethinyl oestradiol in girls with Turner syndrome aged > or =11 years did not negatively influence glucose levels, but induced higher levels of insulin indicating relative insulin resistance. These changes in insulin levels were independent of the frequency of the GH injections (once vs. twice daily). After discontinuation of GH treatment, insulin values decreased to baseline levels.     

Effect of growth hormone and 17beta-oestradiol treatment on metabolism and body composition in girls with Turner syndrome

OBJECTIVE: Girls with Turner syndrome (TS) receive GH treatment during childhood, and in adolescence this treatment may be combined with oestradiol. We have studied the effects of this combined treatment on metabolism and body composition. MATERIAL AND METHODS: We performed a double-blind, placebo-controlled, randomized, crossover study. All girls with TS (n = 8, 16 +/- 2 years) were treated with placebo + placebo, GH + placebo or GH + 17beta-oestradiol for 2 months, and were studied at the end of each period. Controls (n = 10, 14 +/- 2 years) were studied once without treatment. Twenty-four-hour sampling of oestradiol, growth factors, insulin, glucose, lipolytic and gluconeogenic precursors was performed, followed by an oral glucose tolerance test (OGTT) and assessment of body composition and mineral content. RESULTS: GH induced insulin resistance, which was not aggravated further by concomitant oestradiol treatment. The 24-h integrated serum 17beta-oestradiol was reduced compared to controls (0.58 +/- 0.32 vs. 2.81 +/- 2.78 nmol/l/24 h, P = 0.032), but increased during GH + oestrogen (E2) treatment without reaching control levels, while GH + placebo caused a further reduction (anova, P = 0.008). Total fat mass was increased in girls with TS compared with controls (P = 0.009), while lean body mass (P = 0.02) and bone mineral content (P = 0.04) was decreased, with specific regional characteristics in body composition. CONCLUSION: GH treatment induces insulin resistance and changes in body composition in TS, which is not further compromised by concomitant oestradiol treatment. Body composition is changed in TS, with specific regional changes, in comparison with controls. Integrated 24-h oestradiol is low in TS, and is only partially restored during treatment with standard doses of 17beta-oestradiol.     

Investigation of cardiac status and bone mineral density in Turner syndrome

This review highlights recent developments in the detection and management of congenital heart disease and osteoporosis in patients with monosomy X, or Turner syndrome (TS). Magnetic resonance angiography (MRA) using gadolinium as a contrast agent demonstrates a higher prevalence and greater diversity of congenital cardiovascular defects than previously recognized in TS. Almost 50% of girls and women with TS have marked tortuosity or ectasia of the aortic arch, suggesting that these individuals may be at greater risk for aneurysm formation or dissection and therefore require closer monitoring. MRA also reveals that major venous anomalies are common in TS, with partial anomalous pulmonary venous return and persistent left superior vena cava each found in about 13% of patients. MR imaging even without contrast is a valuable complement to routine cardiac ultrasound in detecting abnormalities of the aortic valve. Abnormal electrocardiographic findings, including prolongation of the QTc interval, have recently been documented in many individuals with TS. Conduction and repolarization abnormalities have not been associated with congenital anatomic defects and are as common in young girls as adults. The clinical significance of these electrophysiological findings is unknown at present, but attention to the ECG in TS is important, particularly in monitoring the QTc when prescribing drugs associated with QT prolongation.Patients with TS are at high risk for osteoporosis as a result of premature ovarian failure and intrinsic bone abnormalities specific to the syndrome. Low cortical bone mineral density (BMD) is apparent in prepubertal girls, and it remains low in adults, independent of estrogen treatment and other hormonal factors. The low mineralization of cortical bone in TS may be associated with a small increased fracture risk, but no treatments are known to increase cortical bone mineral content in TS. Trabecular BMD is normal in TS women who have received continuous estrogen treatment from their mid-teens, although areal densitometry scores may be misleadingly low in very small patients. However, young women with ovarian failure who have not received estrogen treatment for extended periods of time are at high risk for osteoporosis of trabecular bone of the spine, with associated compression fractures and height loss. Therefore, judicious management of estrogen therapy to prevent osteoporosis while minimizing estrogen-associated adverse events is a challenging aspect of care for girls and women with TS.     

Growth hormone treatment of early growth failure in toddlers with Turner syndrome: a randomized, controlled, multicenter trial

CONTEXT: Typically, growth failure in Turner syndrome (TS) begins prenatally, and height sd score (SDS) declines progressively from birth. OBJECTIVE: This study aimed to determine whether GH treatment initiated before 4 yr of age in girls with TS could prevent subsequent growth failure. Secondary objectives were to identify factors associated with treatment response, to determine whether outcome could be predicted by a regression model using these factors, and to assess the safety of GH treatment in this young cohort. DESIGN: This study was a prospective, randomized, controlled, open-label, multicenter clinical trial (Toddler Turner Study, August 1999 to August 2003). SETTING: The study was conducted at 11 U.S. pediatric endocrine centers. SUBJECTS: Eighty-eight girls with TS, aged 9 months to 4 yr, were enrolled. INTERVENTIONS: Interventions comprised recombinant GH (50 mug/kg.d; n = 45) or no treatment (n = 43) for 2 yr. MAIN OUTCOME MEASURE: The main outcome measure was baseline-to-2-yr change in height SDS. RESULTS: Short stature was evident at baseline (mean length/height SDS = -1.6 +/- 1.0 at mean age 24.0 +/- 12.1 months). Mean height SDS increased in the GH group from -1.4 +/- 1.0 to -0.3 +/- 1.1 (1.1 SDS gain), whereas it decreased in the control group from -1.8 +/- 1.1 to -2.2 +/- 1.2 (0.5 SDS decline), resulting in a 2-yr between-group difference of 1.6 +/- 0.6 SDS (P < 0.0001). The baseline variable that correlated most strongly with 2-yr height gain was the difference between mid-parental height SDS and subjects' height SDS (r = 0.32; P = 0.04). Although attained height SDS at 2 yr could be predicted with good accuracy using baseline variables alone (R(2) = 0.81; P < 0.0001), prediction of 2-yr change in height SDS required inclusion of initial treatment response data (4-month or 1-yr height velocity) in the model (R(2) = 0.54; P < 0.0001). No new or unexpected safety signals associated with GH treatment were detected. CONCLUSION: Early GH treatment can correct growth failure and normalize height in infants and toddlers with TS.     

Trends in age and anthropometric data at start of growth hormone treatment for girls with Turner syndrome in Japan

The purpose of this study is to evaluate the trends in age and anthropometric data for girls with Turner syndrome (TS) at start of growth hormone (GH) treatment in Japan. The data for analysis were obtained from a retrospective cohort, the Foundation for Growth Science, Japan. We analyzed trends in starting age of GH treatment for girls with TS in Japan after dividing subjects (n=1,478) into three registration periods: 1991-1994, 1995-1999 and 2000-2004. We also assessed the ratio of the subpopulation of subjects under five years of age. As results, the mean age (standard deviation (SD)) at start of GH treatment was significantly different among the three groups (10.95 (3.63), 10.15 (3.39) and 8.78 (3.61), p<0.0001). The proportion of the subjects under five years of age increased significantly over time (5.11%, 7.11% and 16.85%, p<0.0001). Mean (SD) height SD scores were also significantly different (-3.41 (0.87), -3.26 (0.81) and -3.17 (0.79), p<0.0001). However, the proportions of the karyotype of 45,X were not significantly different among the three groups (p=0.25). We concluded that age and shortness at initiation of GH treatment had been improving over time. However, these favorable trends have not fully met the conditions recommended by international clinical guidelines for TS.     

Evidence for early initiation of growth hormone and transdermal estradiol therapies in girls with Turner syndrome

Results from the first randomized, controlled trial of growth hormone (GH) therapy in girls with Turner syndrome (TS) followed to final height firmly establish that GH increases final adult stature. It is widely believed that the efficacy of GH is dependent upon the duration of therapy and dosing (longer duration and higher dose give taller final height). In a recent observational study involving more than 1500 French girls with TS, multivariate analyses demonstrated that the age at initiation of GH therapy accounted for a large percentage of the variance (44%) in response. Age at initiation of estrogen therapy was the second most important factor in determining GH effect (later initiation, taller final height), accounting for 22% of the variance. Overall, 0.3 cm in adult height was gained for every year that estrogen therapy was delayed. However, analyses of the French data restricted to patients with induced puberty revealed that those treated with percutaneous estradiol attained a height 2.1 cm taller than those using oral estradiol or other estrogen preparations. In another study, girls receiving GH therapy (n = 14) who were randomized to receive intramuscular (IM) depot estradiol early (12.0–12.9 years) attained at least as much height as those who initiated it late (14.0–14.9 years). These results are consistent with the observations in adult women that oral estrogens decrease IGF-I serum levels and suppress the IGF-independent metabolic effects of GH, while transdermal estrogens do not. Taken together, these studies suggest that girls with TS should begin GH therapy as soon as growth failure is demonstrated and that puberty should be induced with transdermal or IM estradiol. Girls for whom height is normalized with GH therapy in early childhood have the opportunity to undergo puberty at an age-appropriate time and still achieve a normal adult stature.     

Adult height in sixty girls with Turner syndrome treated with growth hormone matched with an untreated group

The main clinical feature of Turner syndrome (TS) is growth failure, with a mean spontaneous adult height ranging between 136 and 147 cm, according to the specific curves of various populations. Though a classical deficiency of GH has not been generally demonstrated, GH has been administered since 1980 in trials, using replacement doses just initially, with a subsequent trend to increase it. We report the outcome of GH therapy given at the fixed dose of 0.33 mg/kg/week in 60 TS girls observed until adult height; 59 untreated TS girls, matched for auxological, karyotypical characteristics and time of observation, born within the same decade served as controls to evaluate GH efficacy. The calculation of the gain in cm over PAH was performed on specific Italian Turner curves, as well as height evaluation as SD score and growth velocity. The same calculations were made using Lyon references and Tanner standards. The mean CA at the beginning of GH treatment was 10.9 +/- 2.76 yr (range 4.5-15.9). Mean adult height of treated group was 151 +/- 6.1 cm with a gain over the PAH calculated at start of therapy (142.9 +/- 5.3 cm) of 8.2 +/- 3.9 cm. Ns change was observed between the PAH at first observation (143.6 +/- 7.0 cm) and adult height (144.3 +/- 5.6 cm) in the control group. Treatment was well tolerated, no relevant side effects were observed, glucose metabolism resulted no more affected than in untreated subjects, IGF-I levels remained within 2 SD. Our results in 60 TS girls, though the dose remained unchanged throughout the treatment, show a good response, characterized by a striking variability in each patient (mean gain in cm over PAH at adult height of 8.17 +/- 3.9, range 3-21 cm), and significant also in comparison with the control group. As the chronological age at start of therapy ranged between 4.5 to 15.9 yr, the results were further evaluated dividing the patients into two groups, according to the age, < or >11 yr. Thirty girls were <11 yr (mean 8.7 +/- 1.76 yr) and 30 were >11 yr (mean 13.2 +/- 1.4 yr). The gain in cm over the PAH in each group was, respectively, 8.1 +/- 3.4 and 8.2 +/- 4.3 cm without any significant difference between the two groups, showing no negative correlation between the CA at the beginning of GH and the response to treatment.