Does growth-hormone supplementation affect adult height in Turner's syndrome?

Adult Height in 299 Patients with Turner Syndrome with or without Growth Hormone Therapy: Results and Literature Review

CONTEXT

Treatment with growth hormone (GH) is considered effective in improving adult height (AH) in Turner syndrome (TS). However, there are few studies comparing AH between treated patients and a concurrent untreated group.

OBJECTIVE

To assess the efficacy of GH treatment in improving AH in TS and to review previous published studies with treated and untreated groups.

PARTICIPANTS AND METHODS

We retrospectively analyzed clinical data and AH of a large cohort of GH-treated (n = 168) and untreated (n = 131) patients with TS. Data are shown as median and interquartile range (IQR). We assessed pretreatment variables related with AH and compared our results with 16 studies that also included an untreated group.

RESULTS

The GH-treated group was 6.2 cm taller than the untreated group (AH = 149 cm [IQR 144.5-152.5 cm] vs. 142.8 cm [IQR 139-148 cm], p < 0.001) after 4.9 years of GH treatment with a dose of 0.35 mg/kg/week. AH SDS corrected for target height (TH) was 7.2 cm higher in GH-treated patients. AH SDS ≥-2 was more frequent in GH-treated patients (43%) than in untreated patients (16%, p < 0.001). AH SDS was also more frequently within the TH range in the GH-treated group (52%) than in the untreated group (15%, p < 0.001). Height SDS at start of GH therapy and TH SDS were positively correlated with AH (p < 0.001; R2 = 0.375). Considering the current result together with previous similar publications, a mean AH gain of 5.7 cm was observed in GH-treated (n = 696) versus untreated (n = 633) patients.

CONCLUSIONS

Our study strengthens the evidence for efficacy of GH therapy in patients with TS from different populations.

Height predict incident non-alcoholic fatty liver disease among general adult population in Tianjin, China, independent of body mass index, waist circumference, waist-to-height ratio, and metabolic syndrome

Background

Early-life hormonal and nutritional factors can greatly influence the risk of non-alcoholic fatty liver disease (NAFLD). Adult height is a simple marker for these factors. This study aimed to investigate the association between adult height and NAFLD.

Methods

We performed a prospective cohort study of 35,994 participants aged 25 years or over with measured height at baseline. NAFLD was diagnosed by abdominal ultrasound and self-reported history of alcohol intake. Multivariable Cox proportional hazards regression models were conducted to assess the gender-specific association between height and the risk of NAFLD.

Results

During a follow-up period of 5.5 years, 6245 of 35,994 subjects developed NAFLD. The adjusted hazard ratios (95% confidence interval) of NAFLD for increasing quintiles of height were 1.00 (reference), 0.82 (0.73, 0.92), 0.84 (0.73, 0.97), 0.72 (0.61, 0.85) and 0.63 (0.50, 0.79) (P for trend < 0.0001) in males, and 1.00 (reference), 1.00 (reference), 0.80 (0.69, 0.91), 0.72 (0.61, 0.85), 0.60 (0.49, 0.74) and 0.45 (0.35, 0.59) (P for trend < 0.0001) in females, respectively.

Conclusions

A higher adult height was associated with lower risk of NAFLD among males and females in Tianjin, China.

Bone age is the best predictor of growth response to recombinant human growth hormone in Turner's syndrome

BACKGROUND AND OBJECTIVES:

Recombinant human growth hormone (rhGH) is approved for use in children with Turner’s syndrome (TS) in most industrialized countries and is recommended in the recently issued guidelines. We determined the growth responses of girls who are treated with rhGH for TS, with an aim to identify the predictors of growth response.

MATERIALS AND METHODS:

Fifty-six prepubertal girls with TS, documented by peripheral blood karyotype, were enrolled. All the patients received biosynthetic growth hormone therapy with a standard dose of 30 IU/m²/week. The calculated dose per week was divided for 6 days and given subcutaneously at night.

RESULTS:

This study showed that rhGH therapy provides satisfactory auxological results. Bone age delay is to be considered as a predictive factor which may negatively influence the effect of rhGH therapy on final height. The growth velocity in the preceding year is the most important predictor of rhGH therapy response.

CONCLUSION:

These observations help us to guide rhGH prescription, to reduce the risks and costs.

Moving toward an understanding of hormone replacement therapy in adolescent girls: looking through the lens of Turner syndrome

Turner syndrome (TS) is a relatively common disorder of phenotypic females caused by loss of all or part of the second sex chromosome. Most individuals with TS have short stature and gonadal dysgenesis and are at risk for many other medical and learning problems. In the 45,X ovary, germs cells multiply quite normally during fetal development, but there is accelerated atresia of oocytes in the second half of pregnancy that produces gonadal insufficiency by birth. In girls with other karyotypes, especially those mosaic for 45,X/46,XX, gonadal function may be normal or near-normal. In this chapter, management goals for gonadal insufficiency in girls with TS are presented. The effects of estrogen deficiency and its replacement on three specific problems associated with TS-short stature, cardiovascular disease, and developmental differences in brain structure and function-are explored. General guidelines for estrogen replacement therapy using transdermal estrogen, the most physiologic option, are provided and future research goals are outlined.

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.

Final height in girls with turner syndrome after long-term growth hormone treatment in three dosages and low dose estrogens

Although GH treatment for short stature in Turner syndrome is an accepted treatment in many countries, which GH dosage to use and which age to start puberty induction are issues of debate. This study shows final height (FH) in 60 girls with Turner syndrome treated in a randomized dose-response trial, combining GH treatment with low dose estrogens at a relatively young age. Girls were randomly assigned to group A (4 IU/m(2).d; approximately 0.045 mg/kg/d), group B (first year, 4 IU/m(2).d; thereafter 6 IU/m(2).d), or group C (first year, 4 IU/m(2).d; second year, 6 IU/m(2).d; thereafter, 8 IU/m(2).d). After a minimum of 4 yr of GH treatment, at a mean age of 12.7 +/- 0.7 yr, low dose micronized 17beta-estradiol was given orally. After a mean duration of GH treatment of 8.6 +/- 1.9 yr, FH was reached at a mean age of 15.8 +/- 0.9 yr. FH, expressed in centimeters or SD score, was 157.6 +/- 6.5 or -1.6 +/- 1.0 in group A, 162.9 +/- 6.1 or -0.7 +/- 1.0 in group B, and 163.6 +/- 6.0 or -0.6 +/- 1.0 in group C. The difference in FH in centimeters, corrected for height SD score and age at start of treatment, was significant between groups A and B [regression coefficient, 4.1; 95% confidence interval (CI), 1.4, 6.9; P < 0.01], and groups A and C (coefficient, 5.0; 95% CI, 2.3, 7.7; P < 0.001), but not between groups B and C (coefficient, 0.9; 95% CI, -1.8, 3.6). Fifty of the 60 girls (83%) had reached a normal FH (FH SD score, more than -2). After starting estrogen treatment, the decrease in height velocity (HV) changed significantly to a stable HV, without affecting bone maturation (change in bone age/change in chronological age). The following variables contributed significantly to predicting FH SD score: GH dose, height SD score (ref. normal girls), chronological age at start of treatment, and HV in the first year of GH treatment. GH treatment was well tolerated. In conclusion, GH treatment leads to a normalization of FH in most girls, even when puberty is induced at a normal pubertal age. The optimal GH dosage depends on height and age at the start of treatment and first year HV.

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.

Turner's syndrome: a paediatric perspective

In childhood the symptoms with the greatest impact on girls with Turner's syndrome are: (1) congenital cardiac abnormalities (which can be corrected by surgical intervention); (2) short stature (mean adult height between 142 and 147 cm); and (3) ovarian failure (absent spontaneous puberty). Recent studies have shown that growth hormone (GH) treatment in young girls (8 years of age or younger) with Turner's syndrome results in normalization of adult height in most of the girls when using the 'standard' GH dose of about 4 IU/m(2) per day ( approximately 0.045 mg/kg per day). Higher GH doses (6 or 8 IU/m(2) per day) or the use of oxandrolone may be more effective, but their efficacy on adult height and safety in the very long term still have to be proven. If GH treatment is started early, low-dose oestrogens for induction of puberty can be given at 12 years of age without interfering with the capability of the GH treatment to normalize adult height. GH does not seem to have negative side effects on body proportions, cardiac dimensions, blood pressure, carbohydrate metabolism or bone mineral density.

Aspects of the treatment of Turner syndrome

Several issues have to be considered when taking care of girls and women with Turner syndrome. During childhood, short stature is the primary concern and treatment with growth hormone (GH) is now widely used, often in conjunction with the androgen, oxandrolone. Recent studies indicate that doses used previously in the treatment of short stature have been too small. Induction of puberty should be performed at an appropriate age with reference to the peers of the patient. In adulthood, female sex hormone substitution should be offered to possibly prevent the increased morbidity seen in Turner syndrome, which consists of increased risk of fractures and osteoporosis, a clustering of diseases like ischaemic heart disease, hypertension, stroke and Type 2 diabetes, the latter entities being involved in the insulin resistance syndrome. Furthermore, hypothyreosis are often seen and the risk of Type 1 diabetes may also be increased. Congenital malformations of the heart are frequently seen in Turner syndrome, possibly increasing the risk of dissecting aorta aneurism. Liver enzymes are often elevated in Turner syndrome and there may be an increased risk of cirrhosis of the liver. Mortality does seem to be increased in Turner syndrome and women with the 'pure' 45,X karyotype do seem to be most severely affected. In the clinical practice of Turner syndrome, a careful monitoring of glucose and bone metabolism, weight, thyroid function and blood pressure should be performed. A cardiovascular risk profile should be determined and the patient informed concerning risks and benefits from sex hormone replacement therapy. Based on the available literature, sex hormone replacement therapy is highly recommended, although at present there are no longitudinal data documenting the long-term positive effect of sex steroid substitution. However, hypogonadism is expected to explain at least part of the decreased lifespan found in Turner syndrome. Since general physicians encounter Turner patients infrequently, it is recommended that the care and treatment of Turner syndrome is centralised.

Growth hormone treatment of children with brain tumors and risk of tumor recurrence

GH is increasingly used for treatment of children and adults. It is mitogenic, however, and there is therefore concern about its safety, especially when used to treat cancer patients who have become GH deficient after cranial radiotherapy. We followed 180 children with brain tumors attending three large hospitals in the United Kingdom and treated with GH during 1965-1996, and 891 children with brain tumors at these hospitals who received radiotherapy but not GH. Thirty-five first recurrences occurred in the GH-treated children and 434 in the untreated children. The relative risk of first recurrence in GH-treated compared with untreated patients, adjusted for potentially confounding prognostic variables, was decreased (0. 6; 95% confidence interval, 0.4-0.9) as was the relative risk of mortality (0.5; 95% confidence interval, 0.3-0.8). There was no significant trend in relative risk of recurrence with cumulative time for which GH treatment had been given or with time elapsed since this treatment started. The relative risk of mortality increased significantly with time since first GH treatment. The results, based on much larger numbers than previous studies, suggest that GH does not increase the risk of recurrence of childhood brain tumors, although the rising trend in mortality relative risks with longer follow-up indicates the need for continued surveillance.

Compliance with growth hormone treatment - is it a problem?

Treatments fail for a number of reasons. These include the failure of medicines at a molecular level, failure to achieve the correct diagnosis and therefore use of the correct medication, problems surrounding the doctor-patient relationship, and failure of the service to meet patients' expectations. Compliance is characteristically viewed as the major cause of treatment failures but implicit in the use of the term compliance is the reliance on an imbalance of power where the patient follows what is ordered. Such an approach is likely to lead to failure. A better model is concerned with promoting the full participation of the patient to generate a therapeutic alliance. Despite the need for parental administration and a daily therapeutic regimen there appears to be little evidence to suggest that concordance is a major problem in growth hormone therapy. This is probably because treatment administration relies on the presence of a carer and there are tangible effects. However, concordance is likely to be an issue where there is mismatch between the patient's expectations and those of the doctor. Such a situation may arise when the therapeutic margin is narrow or the therapeutic effect minimal. To resolve this situation, adequate pre-intervention discussion is essential, which should include a clear statement of short- and long-term treatment targets and the likelihood of these being achieved or not. Carefully constructed health care plans are the key and should include educational programmes, home support and regular reinforcement. When concordance problems are suspected, careful consideration needs to be given as to whether the diagnosis is correct, is the treatment really effective and appropriate and does the patient really want the treatment.

Role of oestrogen therapy in the management of short stature in Turner syndrome

It is now clear that parenteral growth hormone (GH) therapy stimulates growth and increases the adult stature of girls with Turner syndrome. In addition, oestrogens are given to almost all girls with this syndrome because of primary hypogonadism. Oestrogens influence both growth and maturation of the epiphyseal growth plates. Therefore, the form and timing of oestrogen therapy may have an important impact on the outcome of other growth-promoting therapies. To examine the impact of the timing of oestrogen initiation on growth, a randomized trial was conducted in patients with Turner syndrome who were receiving GH. Some patients received oestrogen at 12 years of age, while in others this treatment was not started until 15 years of age. Those girls that received oestrogen later were significantly taller as adults. The single most important factor in determining height gain appeared to be the number of years of GH therapy prior to the initiation of oestrogen treatment.

Treatment of achondroplasia with growth hormone: six years of experience

We describe the effects of recombinant hGH (r-hGH) therapy for up to 6 y on stature and body proportions of 35 children with achondroplasia (Ach). Consecutive height (Ht) measurements were plotted on disease-specific Ach growth curves, but age and sex SD scores (SDS) of Ht, sitting Ht, subischial leg length, and Ht velocity were made with respect to Tanner normal standards. r-hGH was administered by daily subcutaneous injections at a median (range) dose of 30 (15.8-40) U/m2 per week [0.06 (0.04-0.08) mg.kg(-1).24 h(-1)]. Patients were treated for 3 (1-6) y from age 2.25 (1.2-9.3) y. Before treatment, Ht SDS was -4.6 (-6.5 to -3.24). Treatment caused a significant increase in Ht SDS year to year until y 4 (ANOVA F = 46.94; p < 0.01) that was subsequently sustained with no significant further change (y 5 and 6 versus y 4, p > 0.05). When the response to r-hGH was also expressed as a change in Ht velocity, there was a significant increase in the first year of therapy that was maintained over subsequent treatment years (ANOVA = 4.28, p = 0.001). Age was the most important variable accounting for the first-year response in Ht SDS (r2 = 0.41, p < 0.001), and dose of r-hGH did not influence this. Increments in sitting Ht SDS were greater than subischial leg length SDS (F = 26.25, p < 0.001; F = 9.04, p < 0.001, respectively). r-hGH treatment improved the Ht position of Ach children relative to their normal and Ach peers without obvious side effects. A young age at initiation of therapy prevented the characteristic Ht deficit from accumulating. The greater increase in spinal Ht accentuated the existing disproportion. The addition of later surgical leg lengthening could offer the possibility of proportionate adult stature just within the normal range.

Final height in girls with Turner's syndrome treated with once or twice daily growth hormone injections. Dutch Advisory Group on Growth Hormone

OBJECTIVES

To study final height in girls with Turner's syndrome treated with once or twice daily injections of growth hormone (GH) in combination with low dose ethinyl oestradiol.

DESIGN

Until final height was reached, the effect of fractionated subcutaneous injections given twice daily was compared with once daily injections of a total GH dose of 6 IU/m2/day. Twice daily injections were given as one third in the morning and two thirds at bedtime. All girls concurrently received low dose oestradiol (0.05 microgram ethinyl oestradiol/kg/day, increased to 0.10 microgram/kg/day after 2.25 years).

PATIENTS

Nineteen girls with Turner's syndrome aged > or = 11 years (mean (SD) 13.6 (1.7) years).

MEASUREMENTS

To determine final height gain, we assessed the difference between the attained final height and the final height predictions at the start of treatment. These final height predictions were calculated using the Bayley-Pinneau (BP) prediction method, the modified projected adult height (mPAH), the modified index of potential height (mIPHRUS), and the Turner's specific prediction method (PTSRUS).

RESULTS

The gain in final height (mean (SD)) was not significantly different between the once daily and the twice daily regimens (7.6 (2.3) v 5.1 (3.2) cm). All girls exceeded their adult height prediction (range, 1.6-12.3 cm). Thirteen of the 19 girls had a final height gain > 5.0 cm. Mean (SD) attained final height was 155.5 (5.4) cm. A "younger bone age" at baseline and a higher increase in height standard deviation score for chronological age (Dutch-Swedish-Danish references) in the first year of GH treatment predicted a higher final height gain after GH treatment.

CONCLUSIONS

Division of the total daily GH dose (6 IU/m2/day) into two thirds in the evening and one third in the morning is not advantageous over the once daily GH regimen with respect to final height gain. Treatment with a GH dose of 6 IU/m2/day in combination with low dose oestrogens can result in a significant increase in adult height in girls with Turner's syndrome, even if they start GH treatment at a relatively late age.

Recombinant human growth hormone: old and novel uses

Recent studies of the growth hormone insulinlike growth factor I (IGFI) axis suggest that these hormones are involved in several physiologic processes, in addition to growth. Thus, several lines of evidence indicate an increasingly important role for recombinant human growth hormone as a part of the modern therapeutic armamentarium. In addition to the treatment of children with growth hormone deficiency, administration of growth hormone appears to be of considerable benefit to girls with Turner syndrome, children with chronic renal failure, and adults with growth hormone deficiency or human immunodeficiency virus (HIV) wasting syndrome. Moreover, its therapeutic use is being investigated in other conditions, such as children with idiopathic short stature, the healthy elderly, and the critically ill. However, long-term surveillance among growth hormone recipients is needed to fully evaluate its risk-benefit profile.

Age-related perception of stature, acceptance of therapy, and psychosocial functioning in human growth hormone-treated girls with Turner's syndrome

This study evaluated the perception of stature, acceptance of therapy, and psychosocial functioning in relation to age at onset and time on treatment during 2 yr of GH therapy in 31 girls with Turner's syndrome grouped by age (group A: 3.7-5.8 yr, n = 9; group B: 7.2-11.8 yr, n = 13; group C: 12.5-16.4 yr, n = 9). The growth response after 2 yr was significant in the 3 groups when calculated in terms of growth norms for untreated Turner girls (mean increase in height SD score: +1.2, +1.5, and +1.1, respectively). The effect was less marked in terms of growth norms for normal girls, particularly in group B (+0.5 SD score). Height was perceived as a problem by most patients, except in the youngest girls at the start of treatment (group A) and in the majority of the adolescents after 2 yr of GH therapy (group C), without evidence of relation to growth response during therapy. The GH injections were fairly well accepted by all patients, except those younger than 6 yr. In all patients, expected adult height was unrealistic and became more realistic with age, whereas no consistent changes were observed in relation to growth response to GH therapy. The Child Behavior Checklist revealed elevated mean scores at the behavioral subscales of attention problems (group A and B), social problems, withdrawal, and anxiety-depression (most obviously in group B). No significant changes were seen during GH therapy. In group C, an elevated mean social problem score at the Youth Self Report and a low mean social self-esteem score at the Self-Esteem Inventory were observed before therapy and showed a significant improvement during 2 yr of GH treatment. These results, however, might be biased due to an increase in social desirability during therapy. We conclude that the perception of height, acceptance of GH therapy, and psychosocial functioning in girls with Turner's syndrome show important differences between age groups, with only slight changes observed during GH therapy.

Near normalization of final height with adapted doses of growth hormone in Turner's syndrome

An adapted GH dose regimen was evaluated in 14 untreated patients with Turner's syndrome. The initial GH dose (0.7 U/kg.BW) was increased by 0.7 U/kg.BW, up to a maximum of 2.1 U/kg.BW, when growth velocity (GV) declined to less than 200% of the pretreatment level. These patients were compared to a group of 17 patients with similar initial characteristics, who received a fixed dose of 0.9 U/kg.BW GH. Tolerance to both GH regimens was excellent. The adapted GH doses only partially prevented the waning effect observed with conventional doses of GH, and the initial goal of doubling GV was only achieved in 42% of the 112 patient-semesters. Doubling the GH dose from 0.7 to 1.4 U/kg.BW increased the GV by 1.6 +/- 1.8 cm/yr (P < 0.006); increasing the GH dose from 1.4 to 2.1 U/kg.BW increased GV by 0.8 +/- 1.3 cm/yr (P = NS). The overall height gain during the 4-yr trial was 25.6 +/- 3.9 cm in the adapted dose group and 21.8 +/- 3.9 cm in the conventional group (P < 0.02). Final height (FH) results were obtained in 12 of 14 patients in the adapted dose group and all 17 patients in the conventional group and compared to the predicted FH using Lyon's method. The estimated height benefit was 10.6 +/- 3.8 cm in the adapted dose group compared to 5.2 +/- 3.7 cm in the conventional group (P < 0.01). Eighty-three percent of the patients in the adapted dose group had an FH superior or equal to -2 SD score for the general population compared to 29% in the conventional group. In conclusion, a marked increment in the GH dose in girls with Turner's syndrome associated with a relatively late age at introduction of estrogen therapy brought 83% of the patients into the lower range of the normal height distribution of the general population.

Advances in endocrinology

Molecular genetics will continue to help us to make precise diagnoses. At present, the expertise to achieve this for a specific disease is often exclusive to one unit with a research interest. It will be important to establish a coordinated approach at a supraregional level to provide molecular diagnosis for rare disorders as a fast reliable clinical service. In addition understanding the molecular mechanisms of disease is likely to direct a search for new treatments. For instance, calcium channel blockers have been used in nesidoblastosis to reduce the hypersecretion of insulin, as a result of the recognition of the role that calcium has in the function of the beta-cell ATP sensitive K+ channel. Although the potential benefits of hGH are now being clearly defined in a range of growth disorders, the treatment is invasive and expensive. It is likely that future endocrine therapeutic developments could include slow release growth hormone preparations, orally active growth hormone mimetics, or even hormone production from an ectopic viral cDNA vector. The next "advances in endocrinology" will also reveal whether leptin will have a therapeutic role in appetite control or even the modulation of pubertal development.