Sudden death in Prader-Willi syndrome during growth hormone therapy

We describe a child with Prader-Willi syndrome (PWS) aged 3 years and 11 months who suddenly died 7 months after the initiation of GH therapy. The child never showed respiratory problems, but suffered from severe obesity. This case raises the question about the association between sudden death in children with PWS (with or without respiratory problems) and GH therapy, as already suspected in the recent past. We suggest that further epidemiological studies are required in order to determine more accurately the frequency of this causal connection and better understand its pathogenesis.     

Deaths in children with Prader-Willi syndrome. A contribution to the debate about the safety of growth hormone treatment in children with PWS

Irrespective of GH treatment, children with Prader-Willi syndrome (PWS) suffer more frequently and more seriously from respiratory problems than healthy children. The pathogenesis of such respiratory problems in PWS seems to be multifactorial in origin, but mainly related to insufficiency of respiratory muscles and pharyngeal narrowness. Deaths of children with PWS are reported among GH treated as well as untreated children. Our data show that also disturbed body composition plays an important role in fatal outcomes, possibly enhancing the ventilation disorder. For several years, in our recommendations we have pointed out the secondary risks of increasing obesity. In addition, it is recommended for all children with PWS, in particular before institution of GH therapy, to have polysomnography and an otorhinolaryngologic examination performed, and tonsillectomy in the case of enlarged tonsils. Furthermore, upper airway infections should be treated aggressively.     

Carbohydrate metabolism is not impaired after 3 years of growth hormone therapy in children with Prader-Willi syndrome

BACKGROUND/AIM: In children with Prader-Labhart-Willi syndrome (PWS), the insulin secretion is reduced, despite obesity, being ascribed to the growth hormone (GH) deficiency of hypothalamic origin. Besides, an increased prevalence of diabetes mellitus was described in this syndrome. Hence, we addressed the questions of how body composition and insulin secretion are interrelated and what impact GH therapy has on the carbohydrate metabolism in PWS. METHODS: We measured weight, lean and fat mass (by dual-energy X-ray absorptiometry), triglycerides, HbA(1c), and fasting insulin and glucose levels in 17 children (age range 1.5-14.6 years) with PWS to examine whether the carbohydrate metabolism is altered during 36 months of therapy with 8 mg GH/m(2) body surface/week. In a subgroup of 8 children, the insulin secretion was longitudinally assayed during oral glucose tolerance at 0 and 12 months of therapy. RESULTS: Before therapy, the insulin secretion was lower and markedly delayed as compared with reference data and did not rise during therapy. The glucose tolerance was impaired in 2 of 12 children examined by oral glucose tolerance test before therapy and normalized during therapy. Fasting insulin and insulin resistance being normal at the beginning, significantly increased at 12 months and returned to initial levels at 36 months of GH therapy. Fasting glucose as well as HbA(1c) and triglyceride levels were always normal. The fat mass before GH therapy was increased (39.5%) and dropped into the upper normal range (28.3%) during 3 years of therapy, being correlated with fasting insulin concentration and indices of insulin sensitivity before and after 1 year of therapy. CONCLUSIONS: Children with PWS are characterized by an intact insulin sensitivity with a decrease and a delay of insulin secretion, regardless of moderate obesity or GH treatment. In the present setting, the carbohydrate metabolism is not impaired by GH therapy, but by the excessively increased fat mass.     

Is there growth hormone deficiency in prader-willi Syndrome? Six arguments to support the presence of hypothalamic growth hormone deficiency in Prader-Willi syndrome

Prader-Labhart-Willi syndrome (PWS) is the most frequent form of syndromal obesity. Its main features are associated with hypothalamic dysfunction, which has not yet been comprehensively described. The aim of this review is to present arguments to define the presence of genuine growth hormone (GH) deficiency (GHD) in these patients. Decreasing growth velocity despite the onset of obesity, reduced lean body mass in the presence of adiposity, small hands and feet, relatively low insulin-like growth factor-I and low insulin levels, as well as the dramatic effect of GH treatment on growth, support the presence of hypothalamic GHD in PWS. Even though it might be difficult to ultimately prove GHD in PWS because of the obesity-induced counterregulation, the hormonal situation differs from that in simple obesity. The effects of long-term therapies with GH on body composition in these patients are summarized. GH therapy dramatically changes the phenotype of PWS in childhood: height and weight become normal and there is a sustained impact on the net loss of body fat. We conclude that GHD may account for several features of PWS.     

Body composition abnormalities in children with Prader-Willi syndrome and long-term effects of growth hormone therapy

Obesity and hypothalamic GH deficiency contribute in different ways to the disturbances of body composition in Prader-Willi syndrome (PWS); while both increase the fat compartment, the reduction of lean tissue mass has been attributed mainly to GH deficiency. Therefore, body composition measured by dual-energy X-ray absorptiometry was prospectively studied in 12 overweight children with PWS and weight for height (WfH) SDS >0 before and during 3.5 years of treatment with hGH (0.037 mg/kg/day) on average. In the long term, there is a net reduction of body fat from 3.1 to 1.2 SD, with a minimum at the end of the second year of treatment. WfH SDS correctly reflects body fat mass and its changes. The initial deficit of lean mass (-1.6 SD) is counteracted by GH only during the first year of therapy (increase to -1.25 SD). But in the long term, GH therapy does not further compensate for this deficit, when lean mass is corrected for its growth-related increase. In conclusion, exogenous GH changes the phenotype of children with PWS: fat mass becomes normal, but, at least in the setting studied, GH is not sufficient to normalize lean tissue mass.     

Hyperghrelinemia is a common feature of Prader-Willi syndrome and pituitary stalk interruption: a pathophysiological hypothesis

BACKGROUND: Elevated plasma ghrelin levels have recently been reported in adults and children with Prader-Willi syndrome (PWS). The aim of the study is to investigate the relationship between obesity, growth hormone (GH) deficiency (GHD) and ghrelinemia in PWS and to examine whether hyperghrelinemia is specific to PWS. METHODS: We measured fasting ghrelinemia in children with PWS, idiopathic GHD (iGHD), obese children, controls and in 6 children presenting another congenital syndrome associated with GHD: pituitary stalk interruption (PSI). RESULTS: Children with PWS exhibited significantly higher ghrelin levels (995 pg/ml (801/1,099, median 1st/3rd quartile)) than iGHD (517 pg/ml (392/775)), obese (396 pg/ml (145/610)) and control (605 ng/ml (413/753)) children. Similar to PWS hyperghrelinemia was found in PSI children (1,029 pg/ml (705/1,151)), and was not modified by GH treatment. CONCLUSION: We conclude that hyperghrelinemia in PWS and PSI is not related to GH secretion. We hypothesize that a major site of ghrelin action is at the hypothalamic level and that a 'ghrelin resistance' syndrome may be present in these patients, primarily due to a hypothalamic defect. Combined alterations such as impaired serotonin receptor regulation associated with abnormal ghrelin responsiveness are probably responsible for obesity in PWS.     

Growth hormone treatment downregulates serum leptin levels in children independent of changes in body mass index

The changes in serum leptin levels during growth hormone (GH) treatment were studied in 27 children, 17 with GH deficiency (GHD), 10 with idiopathic short stature (ISS), and 9 with Prader-Willi syndrome (PWS). Within 1 month of GH treatment, serum leptin levels decreased by 40% in the GHD children (p < 0.01). There was no significant change in serum leptin level in the children with ISS. In children with PWS, the mean serum leptin level decreased by almost 60% after 3 months of treatment (p < 0.001). Thereafter, no further decline was observed in any of the 3 groups. Changes in body composition became evident first after the 3 months of treatment. In the GHD children, the BMI was unchanged while the mean body fat percentage was 2.7% lower after 1 year of GH treatment (p < 0.05). In the ISS children, neither BMI nor body fat percentage were significantly changed during treatment. The PWS children exhibited a significant decrease in BMI after 6 months of GH treatment without any further change during the remaining period of treatment. In this group, the mean body fat percentage decreased from 42 +/- 2.4 to 28 +/- 2.2% after treatment (p < 0.001). The finding that the fall in leptin occurs before changes in body composition become detectable suggests a direct effect of GH on leptin production, metabolism, or clearance.     

Effects of growth hormone therapy on glucose metabolism and insulin sensitivity indices in prepubertal children with Prader-Willi syndrome

In Prader-Willi syndrome (PWS) growth hormone therapy (GHT) improves height, body composition, agility and muscular strength. In such patients it is necessary to consider the potential diabetogenic effect of GHT, since they tend to develop type 2 diabetes, particularly after the pubertal age. The aim of our study was to investigate the effects of GHT on glucose and insulin homeostasis in PWS children. An oral glucose tolerance test (OGTT) was performed in 24 prepubertal PWS children (15 male, 9 female, age: 5.8 +/- 2.8 years), 16 were obese (group A) and 8 had normal weight (group B), before and after 2.7 +/- 1.3 years GHT (0.22 +/- 0.03 mg/kg/week) and, only at baseline, in 35 prepubertal children with simple obesity (19 male, 16 female) (group C). Fasting glucose and insulin, glucose tolerance, insulin sensitivity index (ISI), homeostasis model assessment of insulin resistance (HOMA-IR), quick insulin check index (QUICKI), area under the curves (AUC) of glucose and insulin were estimated. At the start of GHT, all PWS children were normoglycaemic and normotolerant but two developed impaired glucose tolerance after 2.2 and 1.9 years of therapy, respectively. At baseline, group A showed lower fasting insulin levels, HOMA-IR and AUC of insulin, higher ISI, QUICKI and AUC of glucose than group C. Comparing groups A and B, AUC of insulin was higher and ISI lower in group A. During GHT, a significant increase of fasting insulin and glucose, a worsening of insulin resistance (HOMA-IR) and insulin sensitivity (QUICKI) was found only in group A while ISI did not change. The AUC of glucose decreased in both groups instead AUC of insulin did not change. BMI-SDS decreased in group A and increased in group B. The increased insulin resistance and decreased insulin sensitivity in obese PWS patients, as well as the occurrence of impaired glucose tolerance during GHT, suggest that a close monitoring of glucose and insulin homeostasis is mandatory, especially in treated obese PWS children.     

Inflammatory markers in adults with Prader-Willi syndrome before and during 12 months growth hormone treatment

BACKGROUND: In Prader-Willi syndrome (PWS) obesity and partial growth hormone (GH) deficiency are frequently observed. The risks of cardiovascular diseases and early death are increased. We examined inflammatory markers in adult PWS, before and during 12 months of GH treatment. METHOD: Twelve PWS adults, median age 23.5 years (17-37) and median BMI 33.8 kg/m2 (21.2-50.4), participated. Serum interleukin-6, tumour necrosis factor alpha, high sensitive protein C-reactive protein (HCRP), cholesterol, triglycerides, leptin, adiponectin, glucose, insulin, insulin-like growth factor I and body composition were measured at baseline and after 6 and 12 months of GH treatment. RESULTS: Median and range at baseline for interleukin-6 was 9.87 ng/l (1.76-10.72), for tumour necrosis factor alpha 2.39 ng/l (1.00-3.26) and for HCRP 7.64 mg/l (0.41-41.1) (normal values < 5 ng/l, < 8 ng/l and<5 mg/l, respectively). At baseline correlations between inflammatory markers and age, anthropometry, body composition and the metabolic parameters were non-significant; only positive associations were found between tumour necrosis factor alpha and body weight (r = 0.617, p = 0.033) and between HCRP and BMI (r = 0.594, p = 0.041). GH treatment non-significantly decreased the levels of the inflammatory markers. CONCLUSION: In this pilot study, levels of interleukin-6 and HCRP were increased, and GH intervention did not significantly reduce the levels. Chronic inflammation might contribute to the increased cardiovascular morbidity and mortality in PWS.     

Treatment of thoraco-lumbar curves in adolescent females affected by idiopathic scoliosis with a progressive action short brace (PASB): assessment of results according to the SRS committee on bracing and nonoperative management standardization criteria

 

In children with Prader Willi syndrome (PWS), besides growth hormone (GH) therapy, control of the food environment and regular exercise, surgical treatment of scoliosis deformities seems the treatment of choice, even though the risks of spinal surgery in this specific population is very high. Therefore the question arises as to whether the risks of spinal surgery outweigh the benefits in a condition, which bears significant risks per se. The purpose of this systematic review of the Pub Med literature was to find mid or long-term results of spinal fusion surgery in patients with PWS, and to present the conservative treatment in a case study of nine patients with this condition.

Methods

Types of studies included; all kinds of studies; retrospective and prospective ones, which reported upon the outcome of scoliosis surgery in patients with PWS. Types of participants included: patients with scoliosis and PWS. Type of intervention: surgery. Search strategy for identification of the studies; Pub Med; limited to English language and bibliographies of all reviewed articles. Nine patients with PWS from our data-base treated conservatively have been found, being 19 years or over at the time this study has been performed. The results of conservative management are described and related to the natural history and treatment results found in the Pub Med review.

Results

From 2210 titles displayed in the Pub Med database with the key word being "Prader Willi syndrome", 5 different papers were displayed at the date of the search containing some information on the outcome of surgery and none appeared to contain a mid or long-term follow-up. The PWS patients treated conservatively from our series all stayed below 70° and some of which improved.

Discussion

If the curve of scoliosis patients with PWS can be kept within certain limits (usually below 70 degrees) conservatively, this treatment seems to have fewer complications than surgical treatments. The results of our retrospective study of nine patients demonstrate that scoliosis in this entity plays only a minor role and surgery is unnecessary when high quality conservative management exists.

Conclusion

There is lack of the long follow-up studies in post-surgical cases in patients with PWS and scoliosis. The rate of complications of spinal fusion in patients with PWS and scoliosis is very high and the death rates have been found to be higher than in patients with Adolescent Idiopathic Scoliosis (AIS). The long-term side-effects of the intervention are detrimental, so that the risk-benefit ratio favours the conservative approaches over spinal fusion surgery.     

Maintenance of a normal meal-induced decrease in plasma ghrelin levels in children with Prader-Willi syndrome.

Ghrelin is a 28-amino acid peptide recently identified in the stomach as the endogenous ligand for the growth hormone secretagogue receptor (GHS-R1a). Ghrelin is a potent stimulator of GH secretion. It was recently shown that circulating ghrelin levels in humans rise shortly before and fall shortly after every meal, and that ghrelin administration increases voluntary food intake. The hypothesis that ghrelin hypersecretion might contribute to genetic obesity has never been investigated. In this context, Prader-Willi syndrome is the most common form of human syndromic obesity. As ghrelin affects appetite as well as GH secretion and both are abnormal in PWS, it has been surmised that these alterations might be due to ghrelin dysregulation. The aim of the study was to investigate whether ghrelin is suppressed by the meals differently in PWS children than in PWS adults. Overnight circulating fasting ghrelin levels and ghrelin levels 120 min after breakfast were assayed in 7 PWS children (10.2 +/- 1.7 yr), 7 subjects with morbid obesity (10.3 +/- 1.3 yr), and 5 normal controls (8.4 +/- 1.4 yr). Because of the data spread, no statistical difference was observed in fasting ghrelin levels between PWS and control children (p = NS); anyway, fasting ghrelin levels were significantly lower in obese children than in the other groups (p < 0.05 vs. control and PWS children). Ghrelin levels were slightly suppressed by the meal in control subjects (mean fasting ghrelin: 160.2 +/- 82 pg/ml; after the meal, 141.2 +/- 57 pg/ml, p = NS); the meal failed to suppress ghrelin levels in obese children (mean fasting ghrelin: 126.4 +/- 8.5 pg/ml; after the meal, 119.1 +/- 8.3 pg/ml, p = NS). Interestingly, the meal markedly suppressed ghrelin levels in PWS children (mean fasting ghrelin: 229.5 +/- 70.4 pg/ml; after the meal, 155.8 +/- 34.2 pg/ml, p < 0.01). In conclusion, since a lack of decrease in circulating ghrelin induced by the meal was previously reported in PWS adults, the finding of a meal-induced decrease in ghrelin levels in our population of young PWS would imply that the regulation of the ghrelin system involved in the orexigenic effects of the peptide is operative during childhood, although it progressively deteriorates and is absent in adulthood when hyperphagia and obesity progressively worsen.     

Proteins and proteases of Prader–Willi syndrome: a comprehensive review and perspectives

Prader–Willi Syndrome (PWS) is a rare complex genetic disease that is associated with pathological disorders that include endocrine disruption, developmental, neurological, and physical problems as well as intellectual, and behavioral dysfunction. In early stage, PWS is characterized by respiratory distress, hypotonia, and poor sucking ability, causing feeding concern and poor weight gain. Additional features of the disease evolve over time. These include hyperphagia, obesity, developmental, cognitive delay, skin picking, high pain threshold, short stature, growth hormone deficiency, hypogonadism, strabismus, scoliosis, joint laxity, or hip dysplasia. The disease is associated with a shortened life expectancy. There is no cure for PWS, although interventions are available for symptoms management. PWS is caused by genetic defects in chromosome 15q11.2-q13, and categorized into three groups, namely Paternal deletion, Maternal uniparental disomy, and Imprinting defect. PWS is confirmed through genetic testing and DNA-methylation analysis. Studies revealed that at least two key proteins namely MAGEL-2 and NECDIN along with two proteases PCSK1 and PCSK2 are linked to PWS. Herein, we summarize our current understanding and knowledge about the role of these proteins and enzymes in various biological processes associated with PWS. The review also describes how loss and/or impairment of functional activity of these macromolecules can lead to hormonal disbalance by promoting degradation of secretory granules and via inhibition of proteolytic maturation of precursor-proteins. The present review will draw attention of researchers, scientists, and academicians engaged in PWS study and will help to identify potential targets and molecular pathways for PWS intervention and treatment.     

Prader-Willi syndrome: Methylation study or fluorescence in situ hybridization first?

Prader-Willi syndrome (PWS) is neurogenetic disorder involving the imprinting mechanism at 15q11-13 region. We report a 4-year-old girl who was referred to our laboratory to be investigated for clinical obesity, mental deficiency and respiratory problems. The patient was born for non-consanguineous and healthy biological parents. After normal pregnancy, the patient was delivered by cesarean section at full term, with a birth weight of 2500 g, and the height and head circumference were unknown. In neonatal stage, she presented severe hypotonia with feeding problems. Her developmental progress was delayed. She walked and developed speech at the age of 3 years. Since the age of 3 years, she presented severe dental problems. Methylation study had confirmed the diagnosis, and for detecting etiology, fluorescence in situ hybridization using probes for small nuclear ribonucleoprotein polypeptide N (SNRPN), which map inside the chromosomal region 15q11-15q13, was necessary to confirm the 15q11-15q13 deletion of paternal chromosome 15, which is the predominant genetic defect in PWS. In conclusion, we report this case with an objective to reinforce the necessity of analysis of DNA methylation within the 15q11-13 region, which is an important tool for the correct diagnosis among children presenting with neonatal hypotonia, mental deficiency and obesity.     

Reports of two cases of selective adrenocorticotropin (ACTH) and growth hormone (GH) deficiency: differential diagnosis from cases with isolated ACTH deficiency associated with transient GH insufficiency

An acquired partial pituitary insufficiency with selective ACTH and GH deficiency was demonstrated in two men aged 47 and 54, for which the clinical course over many years corresponds to Addison's disease. In one of the 2 cases, antibodies to anterior pituitary cell membrane, assayed by an immunofluorescence method with GH3 cells (rat GH and prolactin secreting cell) and AtT-20 cells (mouse ACTH secreting cell) as antigens, were positive. We also present a 55-year-old man with isolated ACTH deficiency associated with transient GH deficiency. In this case, hydrocortisone replacement corrected his subnormal, pre-therapy GH response to insulin tolerance and glucagon propranolol tests, although there was no response of serum GH to L-dops and arginine stimulation test before therapy. Selective ACTH and GH deficiency are very rare and the finding of transient GH insufficiency in a patient with isolated ACTH deficiency suggests that repeated testing while on hydrocortisone replacement therapy is of great diagnostic importance in order to distinguish between selective ACTH and GH deficiency and isolated ACTH deficiency accompanied by transient GH insufficiency.     

Turner syndrome, insulin sensitivity and growth hormone treatment

Mild insulin resistance appears to be an early metabolic defect in girls with Turner syndrome (TS). Impaired glucose tolerance has been reported in 10-34% of patients with TS, and type 2 diabetes mellitus is 2-4 times more common and occurs at a younger age in girls with TS than in the general population. In a mixed longitudinal and cross-sectional study, we analysed carbohydrate tolerance and insulin sensitivity in 46 children and adolescents with TS who reached their final height after long-term treatment (mean 6.3 +/- 2.5 years) with growth hormone (GH: 0.33 mg/kg/week [0.05 mg/kg/day]), and in 36 of these patients who were followed-up after the cessation of GH therapy (mean follow-up, 2.6 +/- 2.5 years; range, 1-9.5 years). Patients with TS were compared with an age-matched female control group. Insulin sensitivity appeared to be lower in patients with TS than in controls, even before the start of GH therapy. As in controls, insulin sensitivity decreased with age in patients with TS, and levels were lower in those aged >12 years than in those aged <12 years. GH therapy resulted in good catch-up growth in patients with TS, with final height significantly higher than projected height evaluated before the initiation of GH therapy. Insulin sensitivity increased after 7-8 years of therapy and, on the cessation of GH therapy, returned to pre-treatment levels. The increase in insulin sensitivity seen on the cessation of GH therapy appeared to be influenced negatively by body mass index and triglyceride levels, and correlated positively with the number of years since cessation of GH therapy. As in the general population, excess weight and an abnormal lipid profile, in particular excess triglyceride levels, worsened insulin sensitivity. In conclusion, our study confirms that GH therapy reduces insulin sensitivity, but at its cessation there is a return to pre-therapy values. We therefore report a progressive improvement in carbohydrate tolerance and insulin function in patients with TS, despite an increase in age.     

Adherence to Growth Hormone Therapy: Results of a Multicenter Study

ObjectiveTo evaluate the adherence to growth hormone (GH) therapy and identify the influencing factors and outcomes in children.MethodsA total of 217 GH-naïve patients in 6 pediatric endocrinology clinics were enrolled in the study. Structured questionnaires were filled out and patients were evaluated at the initiation and 3rd, 6th, and 12th months of therapy. Patients were categorized into 4 adherence segments based on percentage of doses omitted at each evaluation period, classified as excellent if 0%, good if 5%, fair if 5 to 10%, and poor if > 10%.Results:There was a decrement in adherence to GH therapy during the study period (P = .006). Patients who showed excellent and good adherence to therapy had better growth velocity and growth velocity standard deviation scores (SDSs) (P = .014 and P = .015, respectively). A negative correlation between growth velocity SDS and number of missed injections was also observed (r = − .412; P = .007). A positive correlation between delta insulin-like growth factor-1 (IGF-1) SDS and growth velocity was demonstrated (r = .239; P = .042). IGF-1 levels were significantly higher in patients who showed excellent and good adherence to therapy (P = .01). Adherence was better in boys than in girls (P = .035), but adherence rates were not associated with age, cause of GH treatment, socioeconomic status, person who administered the injections, type of injection device, or GH product.ConclusionPoor adherence to GH therapy was common in our group of patients and was one of the factors underlying suboptimal growth during therapy. Before considering other problems that can affect growth, clinicians should confirm good adherence to therapy. (Endocr Pract. 2014;20:46-51)     

Final height in children with idiopathic growth hormone deficiency treated with a fixed dose of recombinant growth hormone

There is no consensus regarding the optimal dosing of recombinant human growth hormone (rhGH) for children with growth hormone deficiency (GHD). Our objective was to evaluate the final adult height (FAH) in children with idiopathic GHD treated with a fixed rhGH dose of 0.18 mg/kg/week. We reviewed all charts of patients with idiopathic GHD treated with rhGH since 1985 who reached FAH. Ninety-six patients were treated for an average of 5.4 years. The mean age was 11.9 years, the mean height -2.87 standard deviation score (SDS) and the mean FAH was -1.04 SDS. Females had a lower predicted adult height than males at the initiation of therapy (-2.0 vs. -1.01 SDS; p = 0.0087) but a higher FAH - predicted adult height (1.08 vs. 0.04 SDS; p = 0.0026). In multiple regression analysis, the FAH SDS was positively related to the midparental height SDS, the height SDS at GH initiation and growth velocity during the first year of therapy, and negatively correlated with peak GH and bone age at initiation (r(2) = 0.51; p < 0.005). Treatment of children with idiopathic GHD with a fixed dose of 0.18 mg/kg/week rhGH is sufficient to reach FAH within 2 SDS of the normal population range (84%) with an average FAH within -0.5 SDS of midparental height.     

Effect of growth hormone replacement therapy on pituitary hormone secretion and hormone replacement therapies in GHD adults

OBJECTIVE: We tested the impact of commencement of GH replacement therapy in GH-deficient (GHD) adults on the circulating levels of other anterior pituitary and peripheral hormones and the need for re-evaluation of other hormone replacement therapies, especially the need for dose changes. METHODS: 22 GHD patients were investigated in a double-blind randomized study and 90 GHD patients in an open study at baseline and after 6 and 12 months of GH replacement therapy. RESULTS: In the placebo-controlled trial, the FT(3) levels increased after 6 months in the GH-treated group, and in the open study the FT(3) levels tended to increase. Other hormone concentrations did not change in either part of the study. Four patients required an increase in thyroxine dose, while 2 patients needed dose reduction. One originally euthyroid patient required thyroxine replacement. Two patients with originally conserved pituitary-adrenal function developed ACTH insufficiency. The hydrocortisone dose was increased in 1 and decreased in 1 of the 66 patients with secondary hypocortisolism. None of the females required any adjustment of sex hormone replacement therapy. Two of 37 males needed dose increase of testosterone, while 1 needed dose reduction. CONCLUSION: GH replacement therapy required dose adjustments regarding other hormone replacement therapies in 12.2% (n = 11), while initiation of new hormone replacement was performed in 3.3% (n = 3) of the 90 patients during the 1-year follow-up. Monitoring of pituitary hormone axes is advisable after commencement of GH replacement therapy, since changes of hormone replacement therapy was observed in a small but clinically significant number of patients.