Variable effect of growth hormone on growth and final adult height in Scottish patients with Turner's syndrome

Height outcome of the recombinant human growth hormone treatment in Turner syndrome: a meta-analysis

OBJECTIVE

This study sought to determine the effect of the recombinant human growth hormone (rhGH) treatment of Turner syndrome (TS) on height outcome.

METHODS

We searched in MEDLINE, EMBASE and Cochrane Central Register of Controlled Trials and Cochrane Database of Systematic Reviews. A literature search identified 640 records. After screening and full-text assessment, 11 records were included in the systematic review. Methodological quality was assessed using the Cochrane Risk of Bias tool. RevMan 5.3 software was used for meta-analysis. We also assessed the quality of evidence with the GRADE system.

RESULTS

Compared with controls, rhGH therapy led to increased final height (MD = 7.22 cm, 95% CI 5.27-9.18, P < 0.001, I2 = 4%; P = 0.18), height standard deviation (HtSDS) (SMD = 1.22, 95% CI 0.88-1.56, P < 0.001, I2 = 49%; P = 0.14) and height velocity (HV) (MD 2.68 cm/year; 95% CI 2.34, 3.02; P < 0.001, I2 = 0%; P = 0.72). There was a small increase in bone age (SMD 0.32 years; 95% CI 0.1, 0.54; P = 0.004, I2 = 73%; P = 0.02) after rhGH therapy for 12 months. What is more, the rhGH/oxandrolone combination therapy suggested greater final height (MD 2.46 cm; 95% CI 0.73, 4.18; P = 0.005, I2 = 32%; P = 0.22), increase and faster HV (SMD 1.67 cm/year; 95% CI 1.03, 2.31; P < 0.03, I2 = 80%; P < 0.001), with no significant increase in HtSDS and bone maturation compared with rhGH therapy alone.

CONCLUSIONS

For TS patients, rhGH alone or with concomitant use of oxandrolone treatment had advantages on final height.

Response to three years of growth hormone therapy in girls with Turner syndrome

PURPOSE

Short stature is the most common finding in patients with Turner syndrome. Improving the final adult height in these patients is a challenge both for the patients and physicians. We investigated the clinical response of patients to growth hormone treatment for height improvement over the period of three years.

METHODS

Review of medical records from 27 patients with Turner syndrome treated with recombinant human growth hormone for more than 3 years was done. Differences in the changes of height standard deviation scores according to karyotype were measured and factors influencing the height changes were analyzed.

RESULTS

The response to recombinant human growth hormone was an increase in the height of the subjects to a mean value of 1.1 standard deviation for subjects with Turner syndrome at the end of the 3-year treatment. The height increment in the first year was highest. The height standard deviation score in the third year was negatively correlated with the age at the beginning of the recombinant human growth hormone treatment. Different karyotypes in subjects did not seem to affect the height changes.

CONCLUSION

Early growth hormone administration in subjects with Turner syndrome is helpful to improve height response to the treatment.

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.

Validation of growth charts for girls with Turner syndrome

Growth charts, which describe the natural course of growth in Turner syndrome (TS) patients, are commonly used in studies in lieu of control groups. While analysing data, various charts produce different final height estimations and height-gain predictions. The choice of an appropriate chart should be the first task when assessing effects of growth hormone treatment. The purpose of this study was to establish the most appropriate growth chart for the subsequent analysis of growth rate in the patients with TS observed initially for a short time without treatment in our clinic. We propose the criteria that a standardised chart should meet. The obtained height-standardised values (height standard deviation score -- Ht SDS) should represent normal distribution with a mean of 0 and standard deviation of 1; their initial mean value and mean change in these values during observation without treatment should not be different from 0. We studied 62 untreated girls with TS using three different growth charts. The values of Ht SDS based on the Lyon chart showed a significant difference from normal distribution (p < 0.05). Only the mean value of an initiaent from 0 (p = 0.088). The mean change of the Ht SDS value based on Lyon and Ranke charts during the follow-up period was not statistically different from 0 (p > 0.05), whereas the difference was statistically significant when the Wisniewski chart was used. Only the Ranke chart correctly characterised TS girls in our clinic. This analysis indicates the importance of careful selection of an appropriate growth chart for an observed population, before applying it to evaluate the effects of hormonal therapy.

Impact of growth hormone supplementation on adult height in turner syndrome: results of the Canadian randomized controlled trial

BACKGROUND

A randomized, controlled trial of GH supplementation to adult height in girls with short stature due to Turner syndrome was conducted in Canada. We report results in subjects who completed the protocol and subjects who participated in follow-up.

METHODS

One hundred fifty-four girls with Turner syndrome, aged 7-13 yr, were randomly assigned to one of two groups: 1) GH by sc injection six times per week (0.30 mg/kg.wk), and 2) control (C), no GH treatment. Both cohorts received standardized sex steroid replacement starting at a chronological age of 13 yr. Subjects were followed until protocol completion, defined as height velocity less than 2 cm/yr and bone age 14 yr or greater. A subsequent protocol addendum requested follow-up safety and efficacy assessment in all patients at least 1 yr after the last core protocol visit.

RESULTS

One hundred four patients completed the study (61 GH, 43 C), and 50 withdrew (15 GH, 35 C). At protocol completion, mean heights were 147.5 +/- 6.1 (GH) and 141.0 +/- 5.4 cm (C), respectively (P < 0.001). Of those who completed the protocol, 59 (40 GH, 19 C) had height data at least 1 yr after protocol completion; in that group, mean heights were 149.0 +/- 6.4 (GH) and 142.2 +/- 6.6 cm (C), respectively (P < 0.001). At protocol completion and follow-up, the mean height gain due to GH, estimated by analysis of covariance, was +7.2 cm (confidence interval 6.0, 8.4) and +7.3 cm (confidence interval 5.4, 9.2), respectively (both P < 0.001).

CONCLUSIONS

This is the first evidence from a randomized, controlled trial to adult height that GH supplementation with induction of puberty at a near physiological age increases the adult height of girls with Turner syndrome.

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.

Bone Age Progression during the First Year of Growth Hormone Therapy in Pre-Pubertal Children with Idiopathic Growth Hormone Deficiency, Turner Syndrome or Idiopathic Short Stature, and in Short Children Born Small for Gestational Age: Analysis of Data from KIGS (Pfizer International Growth Database)

BACKGROUND/AIMS

The beneficial effects of growth hormone (GH) therapy on statural growth in children are well established, but the effects on skeletal maturation are less clear. The progression of bone age (BA) was therefore studied during the first year of GH treatment in pre-pubertal children with idiopathic GH deficiency (GHD), Turner syndrome (TS) or idiopathic short stature (ISS), and in short pre-pubertal children born small for gestational age (SGA).

METHODS

Cross-sectional data on 2,209 short children with idiopathic GHD, 694 with TS, 569 with ISS and 153 with SGA were analysed. Longitudinal data were also analysed from 308 children with idiopathic GHD, 99 with TS, 57 with ISS and 29 with SGA. All patients included in the study were enrolled in KIGS (Pfizer International Growth Database) and were being treated with recombinant human GH (Genotropin). BA was assessed using the Greulich and Pyle method at baseline and after 1 year of GH therapy.

RESULTS

In all groups of patients the mean progression of BA was 1 year during the year of GH therapy, although there was considerable individual variation. Progression of BA was not correlated with chronological age, BA, height SD score (SDS) or body mass index SDS at the onset of GH therapy. There was also no consistent effect of the GH dose on BA progression.

CONCLUSION

Progression of BA appears to be normal in patients receiving GH in these diagnostic groups, at least over the first year of treatment in pre-puberty.

The use of somatropin (recombinant growth hormone) in children of short stature

The availability of somatropin [recombinant human growth hormone (GH)] has revolutionized the treatment of short stature resulting from GH deficiency. It is also widely used as an adjunct in the treatment of other disorders which do not fit the definition of classic GH deficiency, such as intrauterine growth restriction, Turner syndrome, healthy children with short stature and skeletal dysplasias. The widespread use and ready availability of GH treatment has prompted questions about its tolerability, rationality, and the psychological effects of long-term treatment, leading to several trials. Early treatment of GH deficiency will allow the child to reach his or her genetic potential, although there continues to be marked variability in the criteria used to diagnose the deficiency, and in the treatment schedule, especially during puberty. Treatment has also been shown to have a beneficial effect on growth in children with chronic renal failure, with no adverse effects on the renal function. There are, however, no long-term data to determine final height, or randomized controlled studies to justify routine use of GH in conditions such as intrauterine growth restriction. It remains controversial in conditions such as Turner syndrome and achondroplasia, where the response to treatment is only moderate. Healthy children with short stature have not been shown to have a psychological disadvantage, again proving difficult to justify prolonged GH treatment for idiopathic short stature. Meticulous monitoring, long-term follow-up to adult or near-adult final height, and well-defined endpoints of treatment need to be better clarified. The metabolic effects of treatment on the patient's lipid profile, bone mineral density, and muscle mass need careful documentation, especially with the high doses used in an already susceptible population such as low birthweight children and those with Turner syndrome. Lastly, the psychosocial impact of GH treatment, financial implications, and cost efficacy of treatment in an ever-increasing list of indications should be taken into consideration for rationalizing its use in future.

Favorable final height outcome in girls with Ullrich-Turner syndrome treated with low-dose growth hormone together with oxandrolone despite starting treatment after 10 years of age

The objective of this study was to find out whether moderate doses of growth hormone (GH) in combination with oxandrolone (Ox) and late initiation of puberty could improve adult height even in relatively old patients with Ullrich-Turner syndrome (UTS). Ninety-one patients with UTS were randomly assigned to receive either GH alone (Saizen, Ares-Serono, Geneva) 18 IU/m2/week (0.2 mg/kg/week) by daily s.c. injections (group GH) or a combination of GH and Ox 0.1 mg/kg/day p.o. (group GH + Ox). Prior to treatment mean age was 10.2 years (GH) and 10.5 years (GH + Ox), mean projected adult height (PAH) was 146.4 cm (GH) and 146.7 cm (GH + Ox). During year 2 the GH dose was increased in the GH group to 24 and later to 28 IU/m2/week (0.27 mg and later 0.31 mg/kg/week). In group GH + Ox, the Ox dose was reduced to 0.05 mg/kg/day after the first 12 months of therapy, and during the last treatment years the GH dose was raised to 24-28 IU/m2/week (0.27-0.31 mg/kg/week) due to declining growth promotion. Some of the patients of group GH were later given Ox in addition to GH because of waning growth velocity, whereas some of the patients of group GH + Ox were taken off Ox due to virilizing side-effects of the high Ox dose, thus making up a third group of patients: group GH + transient Ox. Puberty was induced at a mean age of 14.9 years. In group GH + Ox, cumulative growth during 5 years of therapy was twice the growth anticipated from standards of untreated patients with UTS. Forty-seven patients are now near or at final height: in group GH (n = 7), mean final height was 151.7 cm (PAH 148.1 cm, gain 3.6 cm); in group GH + Ox (n = 15), 155.1 cm (PAH 147.2 cm, gain 7.9 cm); and in group GH + transient Ox (n = 25), 152.8 cm (PAH 146.4 cm, gain 6.4 cm). These results should be regarded as an underestimate of true final height since some the patients are still growing. Moderate doses of GH plus Ox and late induction of puberty definitely improved final height even in patients with UTS treated relatively late.

A decade of growth hormone treatment in girls with Turner syndrome in the UK. UK KIGS Executive Group

Fifteen per cent of children treated with growth hormone (GH) are receiving treatment for Turner syndrome, but few results are available on final height in the UK. In this study, data were obtained from the UK KIGS database for 485 girls with Turner syndrome who were treated from 1986, allowing an audit of practice and outcome over 10 years. Over the decade, the mean age of starting growth hormone treatment fell from 10.4 to 8.5 years and the starting dose increased from 0.55 to 0.95 IU/kg/week. The frequency of injections increased from three to six or seven/week. Some girls received suboptimal doses, which also differed depending on whether they were based on weight or surface area. To assess what height gain might be expected at final height, all 52 girls who were prepubertal at the start of treatment, which continued for four years or more, and who had reached final height or had a growth velocity < 2 cm/year were selected. Their mean gain in final height was 5.2 cm and the GH dose was 0.78 IU/kg/week over 5.8 years. Final height gain correlated significantly with duration of treatment, total dose received, and first year response, which itself related to starting dose. This audit shows a changing pattern of treatment over the past decade, which in many instances has been inadequate. When treatment starts before puberty and continues through to final height, with a dose of 30 IU/m2/week in six or seven injections, a mean increase in final height of 5 cm or more would be expected.