Prolactin insufficiency but normal thyroid hormone levels after cranial radiotherapy in long-term survivors of childhood leukaemia

BACKGROUND

Acute lymphoblastic leukaemia (ALL) patients treated with cranial radiotherapy (CRT) have an increased risk of GH deficiency (GHD). Little is known about insufficiencies of prolactin (PRL) and TSH, but also lactation failure has been reported in this population.

OBJECTIVE

To study the long-term outcome of CRT on PRL and thyroid hormone levels in GHD ALL patients and the prevalence of lactation failure.

DESIGN

Case-control study.

PATIENTS

We examined 40 GHD and 4 GH insufficient ALL patients, in median 20 years (range: 8-27) after ALL diagnosis and 44 matched population controls.

MEASUREMENTS

PRL secretion (area under the curve; AUC) after GHRH-arginine test in all patients and matched controls, and PRL and TSH AUC after a TRH-test in 13 patients and 13 controls. And basal PRL and thyroid hormone levels after 5 years with GH therapy and 8 years without GH therapy.

RESULTS

Compared with controls, ALL patients had significantly lower basal and AUC PRL after GHRH-Arginine (P = 0·03, P = 0·02), and AUC PRL after TRH (P = 0·001). After 5 and 8 years, PRL levels decreased further (P = 0·01, P = 0·03), but thyroid hormones remained normal at baseline and at follow-up. PRL insufficiency was significantly associated with increased levels of BMI and insulin. Six out of seven pregnant ALL women reported lactation failure.

CONCLUSIONS

Long-term ALL survivors treated with CRT have GHD and PRL insufficiency, and a high prevalence of lactation failure, but thyroid hormones remained normal. PRL insufficiency was associated with cardiovascular risk.

Deaths among adult patients with hypopituitarism: hypocortisolism during acute stress, and de novo malignant brain tumors contribute to an increased mortality

CONTEXT

Patients with hypopituitarism have an increased standardized mortality rate. The basis for this has not been fully clarified.

OBJECTIVE

To investigate in detail the cause of death in a large cohort of patients with hypopituitarism subjected to long-term follow-up.

DESIGN AND METHODS

All-cause and cause-specific mortality in 1286 Swedish patients with hypopituitarism prospectively monitored in KIMS (Pfizer International Metabolic Database) 1995-2009 were compared to general population data in the Swedish National Cause of Death Registry. In addition, events reported in KIMS, medical records, and postmortem reports were reviewed.

MAIN OUTCOME MEASURES

Standardized mortality ratios (SMR) were calculated, with stratification for gender, attained age, and calendar year during follow-up.

RESULTS

An excess mortality was found, 120 deaths vs 84.3 expected, SMR 1.42 (95% confidence interval: 1.18-1.70). Infections, brain cancer, and sudden death were associated with significantly increased SMRs (6.32, 9.40, and 4.10, respectively). Fifteen patients, all ACTH-deficient, died from infections. Eight of these patients were considered to be in a state of adrenal crisis in connection with death (medical reports and post-mortem examinations). Another 8 patients died from de novo malignant brain tumors, 6 of which had had a benign pituitary lesion at baseline. Six of these 8 subjects had received prior radiation therapy.

CONCLUSION

Two important causes of excess mortality were identified: first, adrenal crisis in response to acute stress and intercurrent illness; second, increased risk of a late appearance of de novo malignant brain tumors in patients who previously received radiotherapy. Both of these causes may be in part preventable by changes in the management of pituitary disease.

Incidence of second neoplasm in childhood cancer survivors treated with GH: an analysis of GeNeSIS and HypoCCS

OBJECTIVE

Childhood cancer survivors are commonly treated with GH for GH deficiency that develops either as a result of primary malignancy or its treatment. One study--the Childhood Cancer Survivor Study (CCSS)--demonstrated increased risk of second neoplasm (SN) in GH-treated childhood cancer survivors compared with non-GH treated, after adjusting for key risk factors. We assessed the incidence of SN in GH-treated childhood cancer survivors in outpatient observational studies of GH replacement.

DESIGN

Retrospective analysis of two prospective cohort studies that collected data on safety of GH replacement as prescribed in clinical practice.

METHODS

Childhood cancer survivors enrolled in Eli Lilly and Company's pediatric (Genetics and Neuroendocrinology of Short Stature International Study (GeNeSIS)) and adult (Hypopituitary Control and Complications Study (HypoCCS)) observational studies of GH treatment were assessed for incidence of SN.

RESULTS

The percentage of childhood cancer survivors treated with GH who developed a SN was 3.8% in pediatric GeNeSIS participants and 6.0% in adult HypoCCS participants. The estimated cumulative incidence of SN at 5 years of follow-up in these studies was 6.2 and 4.8% respectively.

CONCLUSIONS

The incidence of SN in GeNeSIS and HypoCCS GH-treated participants is similar to the published literature and is thus consistent with increased risk of SN in childhood cancer survivors treated with GH. As follow-up times were relatively short (<3 years), longer observation is recommended. Nevertheless, clinicians should be alerted to the possibility of increased risk of SN in childhood cancer survivors treated with GH and continue chronic surveillance.

Prospective safety surveillance of GH-deficient adults: comparison of GH-treated vs untreated patients

CONTEXT

In clinical practice, the safety profile of GH replacement therapy for GH-deficient adults compared with no replacement therapy is unknown.

OBJECTIVE

The objective of this study was to compare adverse events (AEs) in GH-deficient adults who were GH-treated with those in GH-deficient adults who did not receive GH replacement.

DESIGN AND SETTING

This was a prospective observational study in the setting of US clinical practices.

PATIENTS AND OUTCOME MEASURES

AEs were compared between GH-treated (n = 1988) and untreated (n = 442) GH-deficient adults after adjusting for baseline group differences and controlling the false discovery rate. The standardized mortality ratio was calculated using US mortality rates.

RESULTS

After a mean follow-up of 2.3 years, there was no significant difference in rates of death, cancer, intracranial tumor growth or recurrence, diabetes, or cardiovascular events in GH-treated compared with untreated patients. The standardized mortality ratio was not increased in either group. Unexpected AEs (GH-treated vs untreated, P ≤ .05) included insomnia (6.4% vs 2.7%), dyspnea (4.2% vs 2.0%), anxiety (3.4% vs 0.9%), sleep apnea (3.3% vs 0.9%), and decreased libido (2.1% vs 0.2%). Some of these AEs were related to baseline risk factors (including obesity and cardiopulmonary disease), higher GH dose, or concomitant GH side effects.

CONCLUSIONS

In GH-deficient adults, there was no evidence for a GH treatment effect on death, cancer, intracranial tumor recurrence, diabetes, or cardiovascular events, although the follow-up period was of insufficient duration to be conclusive for these long-term events. The identification of unexpected GH-related AEs reinforces the fact that patient selection and GH dose titration are important to ensure safety of adult GH replacement.

Mortality and morbidity in adult craniopharyngioma

A craniopharyngioma (CP) is an embryonic malformation of the sellar and parasellar region. The annual incidence is 0.5-2.0 cases/million/year and approximately 60 % of CP are seen in adulthood. Craniopharyngiomas have the highest mortality of all pituitary tumors. Typical initial manifestations at diagnosis in adults are visual disturbances, hypopituitarism and symptoms of elevated intracranial pressure. The long-term morbidity is substantial with hypopituitarism, increased cardiovascular risk, hypothalamic damage, visual and neurological deficits, reduced bone health, and reduction in quality of life and cognitive function. Therapy of choice is surgery, followed by cranial radiotherapy in about half of the patients. The standardised overall mortality rate varies 2.88-9.28 in cohort studies. Patients with CP have a 3-19 fold higher cardiovascular mortality in comparison to the general population. Women with CP have an even higher risk.

Assessment of primary cancers in GH-treated adult hypopituitary patients: an analysis from the Hypopituitary Control and Complications Study

OBJECTIVE

GH and IGFs have mitogenic properties, causing speculation that GH treatment could increase risk of malignancy. While studies in GH-treated childhood cancer survivors have suggested a slight increase in second neoplasms, studies in GH-treated adults have been equivocal. Design Incidence of de novo and second cancers was evaluated in 6840 GH-treated and 940 non GH-treated adult patients in the Hypopituitary Control and Complications Study pharmacoepidemiological database.

METHODS

Evident cancer cases were evaluated in the main analysis, with sensitivity analyses including probable and possible cancers. Standardized incidence ratios (SIRs) for cancers were calculated using Surveillance, Epidemiology and End Results for the USA and GLOBOCAN for all other countries.

RESULTS

During the mean follow-up of 3.7 years/GH-treated patient, 142 evident cancer cases were identified, giving an overall SIR of 0.88 (95% confidence interval (CI) 0.74-1.04); 95% CIs included the value of 1.0 for each country examined. The SIR for GH-treated patients from the USA (71 cases) was 0.94 (95% CI 0.73-1.18), and for non GH-treated patients from the USA (27 cases) was 1.16 (95% CI 0.76-1.69). For GH-treated patients from the USA aged <35 years, the SIR (six cases) was 3.79 (1.39-8.26), with SIR not elevated for all other age categories; SIR for patients from the USA with childhood onset (CO) GH deficiency (GHD) was 2.74 (95% CI 1.18-5.41). The SIR for colorectal cancer in GH-treated patients (11 cases) was 0.60 (95% CI 0.30-1.08).

CONCLUSIONS

With relatively short follow-up, the overall primary cancer risk in 6840 patients receiving GH as adults was not increased. Elevated SIRs were found for subgroups in the USA cohort defined by age <35 years or CO GHD.

Hypothalamic involvement and insufficient sex steroid supplementation are associated with low bone mineral density in women with childhood onset craniopharyngioma

CONTEXT

Data on bone mineral density (BMD) are lacking in adults with childhood onset (CO)-craniopharyngioma (CP) with hypothalamic damage from the tumor. In patients with CO GH deficiency, BMD increases during GH treatment.

OBJECTIVE

The aims were to evaluate BMD in adults with CO-CPs on complete hormone replacement, including long-term GH and to evaluate the impact of hypothalamic damage on these measures.

DESIGN AND PARTICIPANTS

BMD (dual-energy X-ray absorptiometry), markers of bone turn over, physical activity and calcium intake were assessed in 39 CO-CP adults (20 women), with a median age of 28 (17-57) years, in comparison with matched population controls.

RESULTS

Late puberty induction was recorded in both genders, but reduced androgen levels in females only. Only CP women had lower BMD (P=0.03) at L2-L4, and reduced Z-scores at femoral neck (P=0.004) and L2-L4 (P=0.004). Both genders had increased serum leptin levels (P=0.001), which significantly correlated negatively with BMD at L2-L4 (P=0.003; r=-0.5) and 45% of CP women had Z-score levels ≤-2.0 s.d. Furthermore, 75% of those with a Z-score ≤-2.0 s.d. had hypothalamic involvement by the tumor. Calcium intake (P=0.008) and physical activity (P=0.007) levels were reduced in CP men only. Levels of ostecalcin and crossLaps were increased in CP men only.

CONCLUSIONS

Despite continuous GH therapy, low BMD was recorded in CO-CP females. Insufficient estrogen and androgen supplementation during adolescence was the main cause, but hypothalamic involvement with consequent leptin resistance was also strongly associated with low BMD in both genders.

Bone loss after childhood acute lymphoblastic leukaemia: an observational study with and without GH therapy

OBJECTIVE

Bone mineral density (BMD) in survivors of acute lymphoblastic leukaemia (ALL) seems to vary with time, type of treatments and GH status. We aimed to evaluate BMD in ALL patients with GH deficiency (GHD), with and without GH therapy.

DESIGN

Case-control study.

METHODS

We examined 44 (21 women) GHD patients (median 25 years) treated with cranial radiotherapy (18-24 Gy) and chemotherapy and matched population controls for BMD with dual-energy X-ray absorptiometry. For 5 and 8 years, two subgroups with (0.5 mg/day) (n=16) and without GH therapy (n=13) and matched controls were followed respectively.

RESULTS

At baseline, no significant differences in BMD or Z-scores at femoral neck and L2-L4 were recorded (all P>0.3). After another 8 years with GHD, the Z-scores at femoral neck had significantly decreased compared with baseline (0.0 to -0.5; P<0.03) and became lower at the femoral neck (P=0.05), and at L2-L4 (P<0.03), compared with controls. After 5 years of GH therapy, only female ALL patients had a significantly lower femoral neck Z-scores (P=0.03). The female ALL patients reached an IGF1 level of -0.7 s.d. and male patients reached the level of +0.05 s.d.

CONCLUSIONS

On average, 25 years after diagnosis, GH-deficient ALL patients experienced a significant decrease in Z-scores at femoral neck, and if Z-scores continue to decrease, there could be a premature risk for osteoporosis. GH therapy was not shown to have a clear beneficial effect on BMD. Whether higher GH doses, particularly in women, will improve Z-scores needs further investigation.

Cardiovascular risk, cardiac function, physical activity, and quality of life with and without long-term growth hormone therapy in adult survivors of childhood acute lymphoblastic leukemia

CONTEXT

Long-term data are missing in GH-treated acute lymphoblastic leukemia (ALL) patients. GH therapy may result in poorer outcome regarding cardiovascular (CV) and particularly cardiac effects than in patients with hypothalamic-pituitary disease.

OBJECTIVE

Our objective was to evaluate GH therapy on CV risk, cardiac function, physical activity, and quality of life in ALL patients treated with cranial radiotherapy (18-24 Gy) and chemotherapy (anthracycline dose 120 mg/m2).

DESIGN AND SETTING

We conducted a 5- and 8-yr open nonrandomized prospective study in a university hospital clinic.

STUDY PARTICIPANTS

Two groups of GH-deficient ALL patients (aged 25 yr; range 19-32 yr) and matched population controls participated.

INTERVENTIONS

One ALL group (n=16) received GH for 5 yr, and the other ALL group (n=13) did not receive GH therapy.

MAIN OUTCOME MEASURES

We evaluated the prevalence of CV risk factors and metabolic syndrome (International Diabetes Federation consensus), cardiac function (echocardiography), and quality of life and physical activity questionnaires.

RESULTS

In comparison with 8 yr without, 5 yr with GH therapy resulted in significant positive changes in plasma glucose (-0.5 vs. 0.6 mmol/liter, P=0.002), apolipoprotein B/apolipoprotein A1 ratio (-0.1 vs. 0.0, P=0.03), and high-density lipoprotein-cholesterol (0.20 vs.-0.01 mmol/liter, P=0.008) and a significant reduction in the prevalence of metabolic syndrome (P=0.008). No significant difference in the left-ventricular systolic function or in physical activity and quality of life was recorded before and after 5 or 8 yr, respectively (all P>0.3).

CONCLUSION

GH therapy reduced the CV risk in this young ALL population but resulted in no clear benefit or deterioration in cardiac function.

Prevalence of metabolic syndrome in adult hypopituitary growth hormone (GH)-deficient patients before and after GH replacement

CONTEXT AND OBJECTIVE

Metabolic and body compositional consequences of GH deficiency (GHD) in adults are associated with a phenotype similar to the metabolic syndrome (MetS).

PATIENTS

We assessed MetS prevalence in adult GHD patients (n = 2531) enrolled in the Hypopituitary Control and Complications Study. Prevalence was assessed at baseline and after 3 yr of GH replacement in a subset of 346 adult-onset patients.

RESULTS

Baseline MetS crude prevalence was 42.3%; age-adjusted prevalence in the United States and Europe was 51.8 and 28.6% (P < 0.001), respectively. In the United States, age-adjusted prevalence was significantly higher (P < 0.001) than in a general population survey. Increased MetS risk at baseline was observed for age 40 yr or older (adjusted relative risk 1.34, 95% confidence interval 1.17-1.53, P < 0.001), females (1.15, 1.05-1.25, P = 0.002), and adult onset (1.77, 1.44-2.18, P < 0.001). In GH-treated adult-onset patients, MetS prevalence was not changed after 3 yr (42.5-45.7%, P = 0.172), but significant changes were seen for waist circumference (62.1-56.9%, P = 0.008), fasting glucose (26.0-32.4%, P < 0.001), and blood pressure (59.8-69.7%, P < 0.001). Significantly increased risk of MetS at yr 3 was associated with baseline MetS (adjusted relative risk 4.09, 95% confidence interval 3.02-5.53, P < 0.001) and body mass index 30 kg/m(2) or greater (1.53, 1.17-1.99, P = 0.002) and increased risk (with a P value < 0.1) for GH dose 600 microg/d or greater (1.18, 95% confidence interval 0.98-1.44, P = 0.088).

CONCLUSION

MetS prevalence in GHD patients was higher than in the general population in the United States and higher in the United States than Europe. Prevalence was unaffected by GH replacement, but baseline MetS status and obesity were strong predictors of MetS after GH treatment.

Adult survivors of childhood acute lymphoblastic leukaemia with GH deficiency have normal self-rated quality of life but impaired neuropsychological performance 20 years after cranial irradiation

OBJECTIVE

Cranial radiotherapy (CRT) was, until recently, important for achieving long-term survival in acute lymphoblastic leukaemia (ALL). Because survival rates have improved markedly, the long-term complications, such as GH deficiency (GHD) and neuropsychological impairment, have become increasingly important.

DESIGN AND PATIENTS

The level of self-reported quality of life and neuropsychological functioning was investigated in 44 adults (21 women) with a median age of 25 years who had been treated for childhood onset (CO) ALL with CRT (median 24 Gy). Comparison was made with matched population controls. A subset of patients with GHD was evaluated for neuropsychological functioning after 1 year of GH treatment.

RESULTS

Compared to controls, the patients had significantly lower performance in neuropsychological tests. Early age at treatment had a significant negative impact on neuropsychological performance in adulthood. No relationship was found between dose of CRT, time since treatment of ALL or gender and neuropsychological performance. Compared to controls, the patients did not show a poor quality of life or a lowered availability of social interactions or social networks; however, significantly more patients were living alone or with their parents. After GH testing, the patients were all considered GH deficient or insufficient, but no relationship was observed between stimulated peak GH secretion and neuropsychological performance. Treatment with GH for 1 year in a subgroup of the patients did not improve their neuropsychological performance.

CONCLUSIONS

This study showed that adults treated with CRT for CO ALL had GHD and significantly impaired neuropsychological performance, although self-reported quality of life was not affected. The effect of GH treatment in this patient group has to be further elucidated.

Associations between CB-153 and p,p'-DDE and hormone levels in serum in middle-aged and elderly men

BACKGROUND

Animal and epidemiologic data indicate that exposure to persistent organochlorine pollutants (POPs) may disrupt the hypothalamus-pituitary-thyroid (HPT) and the hypothalamus-pituitary-gonadal (HPG) axes. We have assessed whether the POP-biomarkers 2,2'4,4',5,5'-hexachlorobiphenyl (CB-153) and 1,1-dichloro-2,2-bis(4-chlorophenyl)-ethene (p,p'-DDE) affect thyrotropin (TSH), thyroid hormones, gonadotropins or sex hormone concentrations in men.

METHODS

Lipid adjusted serum concentrations of CB-153, and p,p'-DDE, were determined in 196 men (median age 59 years, range 48-82). Hormone analyses in serum were performed with immunoassays. The effect of CB-153 and p,p'-DDE (as continuous or categorized variables) were evaluated by linear regression models, adjusting for potential confounders.

RESULTS

There was a significant positive association between p,p'-DDE and TSH. An increase of 100 ng/g lipid of p,p'-DDE corresponded to an increase of 0.03 mU/l (95% Confidence Interval (CI) 0.01, 0.05) in TSH level. The explanatory value (R(2)) of the multivariate model was only 7%. Moreover, there was a significant negative association between p,p'-DDE and estradiol. An increase of 100 ng/g lipid of p,p'-DDE corresponded to a decrease of 0.57 pmol/l (95% CI -1.0, -0.12) in estradiol level. The R(2)-value was only 4%. No associations were observed between any of the POP biomarkers and the other hormones.

CONCLUSIONS

The positive association between p,p'-DDE and TSH and the negative association between p,p'-DDE and estradiol, among middle-aged and elderly men, were not accompanied by associations between the POP-markers and thyroxin, testosterone, and gonadotropins, respectively. The results gives some additional support for that POP exposure may affect HPT- and HPG-axes also in humans, but the overall epidemiological data are still not coherent enough to allow any firm conclusions.

Improvement in cardiac systolic function and reduced prevalence of metabolic syndrome after two years of growth hormone (GH) treatment in GH-deficient adult survivors of childhood-onset acute lymphoblastic leukemia

CONTEXT

Survivors of childhood-onset (CO) acute lymphoblastic leukemia (ALL) treated with prophylactic cranial radiotherapy often exhibit GH deficiency (GHD), which is associated with increased prevalence of cardiovascular risk factors and cardiac dysfunction.

OBJECTIVE

The objective of the study was to evaluate the effect of GH replacement on cardiovascular risk factors and cardiac function in former CO ALL patients.

DESIGN

Eighteen former CO ALL patients (aged 19-32 yr) treated with cranial radiotherapy (18-24 Gy) and chemotherapy and with confirmed GHD were studied at baseline and after 12 (n = 18) and 24 months (n = 13) of GH treatment (median 0.5 mg/d). A group of 18 age- and sex-matched subjects served as controls.

RESULTS

After 12 months of GH treatment, a significant decrease in serum leptin (P = 0.002), leptin per kilogram fat mass (FM) (P = 0.01), plasma glucose (P = 0.004), FM (P = 0.002), and hip (P = 0.04) and waist (P = 0.02) circumference and increased muscle mass (P = 0.004) were recorded in the patients. Before GH treatment six patients had a metabolic syndrome, but after 12 months only one had it and after 24 months none. After 24 months of GH treatment, an increase in left ventricular mass index (P = 0.06) and significant improvements in cardiac systolic function, measured as fractional shortening (P = 0.03) and ejection fraction (P = 0.03), were recorded.

CONCLUSIONS

Improvement in cardiac systolic function and reduced prevalence of metabolic syndrome were recorded after 2 yr of GH replacement in former CO ALL patients with GHD. Long-term follow-up is highly warranted.

Risk for severe hypoglycaemia with unawareness in GH-deficient patients during the insulin tolerance test

OBJECTIVE

The insulin tolerance test (ITT) has been suggested as the gold standard for diagnosing GH deficiency (GHD). The ITT is, however, potentially hazardous. Glucose monitoring during the ITT varies between centres and there is surprisingly little information on the actual level of blood glucose nadir and the duration of hypoglycaemia in patients undergoing the ITT. The aim of the present study was to closely monitor the blood glucose level and to register the presence of symptoms and signs of hypoglycaemia during the ITT.

DESIGN AND PATIENTS

Sixteen patients (seven women), aged 22-59 years were consecutively recruited for an ITT, and showed GHD (peak GH < 3 microg/l).

RESULTS

In five (31%) of the patients unawareness of hypoglycaemia was recorded, the median nadir blood glucose level was 1.4 mmol/l (range 1.1-1.9) and the duration of blood glucose < 2.2 mmol/l was 25 min (range 20-33). The remaining 11 patients were symptomatic, and tiredness (n=6) and dizziness (n=3) were the most frequent symptoms. In these symptomatic patients the median nadir blood glucose level was 1.3 mmol/l (range 1.0-1.6) and the duration of blood glucose < 2.2 mmol/l was 25 min (range 15-30).

CONCLUSIONS

In patients with GHD subjected to the ITT, symptoms of hypoglycaemia were scarce and a third showed unawareness. Close blood glucose monitoring is recommended at the ITT as low nadir blood glucose levels and long duration of hypoglycaemia may be present irrespective of symptoms of hypoglycaemia. Recommendations for intervention with intravenous glucose, at unacceptable low blood glucose levels or at prolonged hypoglycaemia, are warranted.

The utility of the growth hormone (GH) releasing hormone-arginine test for diagnosing GH deficiency in adults with childhood acute lymphoblastic leukemia treated with cranial irradiation

CONTEXT

The insulin tolerance test (ITT) is the current standard diagnostic test for the diagnosis of adult GH deficiency (GHD), but alternative tests, such as the GHRH-arginine test, have been proposed.

OBJECTIVE

We investigated the sensitivity and specificity of the GHRH-arginine test using ITT as the gold standard in diagnosing GHD in a group of young adults treated with cranial irradiation (CRT) for childhood acute lymphoblastic leukemia (ALL). We estimated the positive and negative predictive values of the GHRH-arginine test among patients as well as a number of individual characteristics and therapy-related factors during both the GHRH-arginine test and ITT.

DESIGN

Forty-three young adults, treated for childhood ALL with 18-30 Gy CRT and chemotherapy, were studied, and comparison was made with matched controls.

RESULTS AND CONCLUSIONS

We evaluated four different cutoff levels for GHD in the GHRH-arginine test: 5, 7.5, 9, and 16.5 microg/liter. Using 7.5 microg/liter as the cutoff yielded high specificity (94%), but at the same time the sensitivity was only 66%, which leads to a low negative predictive value (27%). In contrast, a failed GH response to the GHRH-arginine test accurately reflects the presence of radiation-induced GHD, illustrated by a high positive predictive value (95% at 7.5 microg/liter). Only age at CRT and body mass index remained significant predictors of the peak GH during the GHRH-arginine test. Because a high proportion of GHD patients show a normal response to the GHRH-arginine test, it cannot be used reliably to exclude GHD in these patients. Complementary ITT is also warranted to confirm GHD in obese patients.

Cerebrovascular disease in patients with pituitary tumors

Several studies have shown that patients with acromegaly have increased mortality rates for cardiovascular disease and cerebrovascular disease (CVD). Similar associations have also been seen for patients with hypopituitarism or with non-functional pituitary adenomas. This review summarizes these data and discusses the relative importance of different risk factors for cardiovascular, especially CVD, mortality among patients with acromegaly or non-functional pituitary adenomas, and for those with hypopituitarism as a result of other causes.

Baseline characteristics and response to 2 years of growth hormone (GH) replacement of hypopituitary patients with GH deficiency due to adult-onset craniopharyngioma in comparison with patients with nonfunctioning pituitary adenoma: data from KIMS (Pfizer International Metabolic Database)

OBJECTIVE

In epidemiological studies, hypopituitary adults show increased mortality compared with population controls. Patients with hypopituitarism caused by a craniopharyngioma (CP) and/or its treatment have a higher mortality than patients with other etiologies, such as a nonfunctioning pituitary adenoma (NFPA). To analyze this difference, we used the KIMS database (Pfizer International Metabolic Database) comparing CP and NFPA patients in terms of baseline characteristics and responses to GH replacement.

PATIENTS

Baseline characteristics were studied in 351 CP patients (189 men and 162 women; mean age, 42.5 yr) and compared with 370 NFPA patients, matched for age and sex (185 men and 185 women; mean age, 42.5 yr). The effects of 2 yr of GH replacement were analyzed in a subgroup of 183 CP and 209 NFPA patients.

RESULTS

At baseline, both CP and NFPA patients had characteristic features of GH deficiency, with low serum IGF-I, increased body fat, dyslipidemia, and reduced quality of life. Male CP patients were significantly more obese (30.0 vs. 28.2 kg/m2; P = 0.0003) compared with NFPA patients, had a higher waist/hip ratio (P = 0.004), higher triglycerides (P = 0.003), and lower high-density lipoprotein cholesterol (P = 0.03). Similar, but much smaller, differences were seen in female CP compared with NFPA patients, only reaching significance for waist/hip ratio (P = 0.05) and triglycerides (P = 0.0004). CP patients had more often undergone surgery by the transcranial route (68.8% vs. 30.9%; P < 0.0001), and panhypopituitarism was more prevalent in CP than in NFPA patients (58.7% vs. 19.8%; P < 0.0001). The incidence of previous fractures, hypertension, coronary heart disease, claudication, and diabetes mellitus was high, but not different, between CP and NFPA patients. After 2 yr of GH replacement therapy, similar significant improvements were evident in both groups in fat-free mass, total and low-density lipoprotein cholesterol, and Quality-of-Life-Assessment in GH Deficient Adults score compared with baseline. In contrast to NFPA patients, CP patients had no significant decrease in body fat with GH therapy.

CONCLUSIONS

In the KIMS database, patients with CP have more often undergone surgery by the transcranial route than patients with NFPA, have a higher prevalence of pituitary deficiencies, are more obese (predominantly males), and have more dyslipidemia. This could provide an explanation, at least in part, for the higher mortality rate in CP patients observed in epidemiological studies. CP patients respond equally well to GH therapy in fat-free mass, lipids, and quality of life, but are less likely to lose body fat. We assume that this difference in response merely reflects the stronger tendency of CP patients to accumulate fat over time.

The clinical, metabolic and endocrine features and the quality of life in adults with childhood-onset craniopharyngioma compared with adult-onset craniopharyngioma

BACKGROUND

Craniopharyngioma is a parasellar tumour that, although benign, tends to behave aggressively. It can occur at any age but most commonly presents in childhood or adolescence.

OBJECTIVES

To investigate the frequency and severity of problems associated with craniopharyngioma, using the large international database (KIMS) for adult patients with GH deficiency (GHD), and to assess the differences between the adult onset (AO, aged 18 or above) disease and adults with childhood onset (CO) craniopharyngioma.

DESIGN

Inclusion criteria were: an established diagnosis of craniopharyngioma, severe GHD and no recent GH treatment. These criteria were fulfilled by 393 (184 female, 209 male) patients; 241 had AO (mean age 28.7 +/- 8.7 years) and 152 had CO disease (age 42.0 +/- 12.3 years). Disease history, clinical features and anthropometric data were recorded at the time of enrolment in the database, and body composition, serum IGF-I, serum lipids and quality of life (QoL) were assessed.

RESULTS

Peak age at onset of craniopharyngioma was 15-20 years. Ninety percent of patients had been treated surgically. CO patients were shorter than AO patients and had much lower IGF-I standard deviation scores (SDS). The majority had hypopituitarism and over 60% had diabetes insipidus. Body mass index (BMI) was higher in AO males (30.2 +/- 5.5) than in CO males (28.5 +/- 7.5); waist circumference was also greater. Obesity was more common in AO patients (51.8% vs 39.1%). Body composition did not differ between groups. Cholesterol and triglycerides were higher in AO than in CO patients, but high density lipoprotein (HDL)- and low density lipoprotein (LDL)-cholesterol did not differ. Quality of life, assessed by Quality of Life-Assessment of Growth Hormone Deficiency in Adults (QoL-AGHDA) and the Nottingham Health Profile, was markedly reduced in all groups with no significant differences between them; the QoL-AGHDA score correlated with age at onset of both craniopharyngioma and GHD, and also with BMI in AO patients.

CONCLUSIONS

These data emphasise the generally poor state of health of patients treated for craniopharyngioma, with respect to endocrine and metabolic function, and also the markedly reduced quality of life. In addition to GHD, most patients have evidence of hypothalamic damage with associated obesity, diabetes insipidus and hypopituitarism. Adults with CO craniopharyngioma were shorter, had lower IGF-I, lower BMI, less obesity and slightly lower blood lipid levels than patients with AO craniopharyngioma.

Survivors of childhood acute lymphoblastic leukaemia, with radiation-induced GH deficiency, exhibit hyperleptinaemia and impaired insulin sensitivity, unaffected by 12 months of GH treatment

OBJECTIVE

Adult survivors of childhood acute lymphoblastic leukaemia (ALL) often exhibit GH deficiency (GHD), due to prophylactic cranial radiotherapy (CRT). It is not known whether the observed risk for adiposity in these patients is associated with impaired insulin sensitivity and whether the insulin sensitivity is affected by GH replacement therapy.

SUBJECTS AND DESIGN

Eleven patients with GHD (median age 29 years), previously given prophylactic CRT for ALL, and 11 sex-, age- and body mass index (BMI)-matched controls were investigated with bioimpedance analysis (BIA) and analysis of serum leptin, serum free fatty acids (FFA) and serum insulin. Insulin sensitivity was measured by a euglycaemic-hyperinsulinaemic clamp technique (IS-clamp). Moreover, the effects of 12 months of individually titrated GH treatment (median dose 0.5 mg/day) on these parameters were investigated.

RESULTS

At baseline, the patients had lower fat free mass (FFM) (P = 0.003), higher percentage fat mass (FM) (P = 0.05), serum insulin (P = 0.02) and serum leptin/kg FM (P = 0.01) than controls. The patients had a tendency towards impaired IS-clamp (P = 0.06), which disappeared after correction for body composition (IS-clamp/kg FFM; P > 0.5). In the patients, time since CRT was positively correlated with percentage FM (r = 0.70, P = 0.02), and there was an independent negative association between serum FFA and IS-clamp (P = 0.05). Twelve months of GH treatment increased serum IGF-I (P = 0.003) and FFM (P = 0.02) and decreased percentage FM (P = 0.03), but no significant changes were seen in serum leptin/kg FM, serum FFA, FFA-clamp, serum insulin or IS-clamp (all, P > or = 0.2).

CONCLUSIONS

Young adult survivors of childhood ALL with GHD had increased fat mass, hyperleptinaemia and impaired insulin sensitivity, which could be a consequence of radiation-induced impairment of GH secretion or mediated by other hypothalamic dysfunctions, such as leptin resistance or other unknown factors, affected by CRT. Twelve months of individualized GH replacement therapy led to positive effects on body composition, but the hyperleptinaemia, hyperinsulinaemia and the impaired insulin sensitivity remained unchanged.

Changes in height, weight, and body mass index in children with craniopharyngioma after three years of growth hormone therapy: analysis of KIGS (Pfizer International Growth Database)

Extreme degrees of obesity may occur in association with hypothalamic tumors, usually after surgical intervention. This phenomenon has been reported to occur in as many as 25-75% of children undergoing extensive surgical extirpation of craniopharyngiomas (Cranio). Because less is known about the auxology of children with Cranio with milder alterations in growth, we undertook a 3-yr longitudinal analysis, using the KIGS database (Pfizer International Growth Database), to study their growth patterns and evolution of weight. We compared the effect of GH therapy on height, weight, and body mass index (BMI) in 199 prepubertal children with diagnosed Cranio treated by surgery and/or radiotherapy to two other groups of children with other causes of organic GH deficiency (OGHD): one with postsurgical and/or postirradiated OGHD (OGHD + S/I; n = 92) and the other with OGHD not due to Cranio and not having undergone either surgery or irradiation (OGHD - S/I; n = 85). At the start of GH therapy, 1) mean chronological (P < 0.0001) and bone (P = 0.0002) ages were youngest in OGHD - S/I and oldest in OGHD + S/I; 2) the mean height sd score (SDS) was lowest in OGHD - S/I and comparably higher in the other two groups (P < 0.0001); 3) mean weight and BMI SDS were greatest in Cranio and least in OGHD - S/I (both P < 0.0001); and 4) the mean initial GH dose prescribed was highest in OGHD - S/I and comparable in the other two groups (P < 0.0001). After 3 yr of GH therapy, 1) mean bone age remained youngest in OGHD - S/I and oldest in OGHD + S/I (P < 0.0001); 2) mean height SDS was highest in Cranio and comparably lower in the other two groups (P = 0.0159); 3) mean weight and BMI SDS remained greatest in Cranio and least in OGHD - S/I (P < 0.0001 and P = 0.0003, respectively); and 4) the mean GH dose remained highest in the OGHD - S/I group and least in the Cranio group (P = 0.0082). There were statistically significant increases within each group between the start of treatment and after 3 yr of GH therapy in height and weight, but not in BMI SDS. Lastly, after 3 yr of GH treatment, children in the Cranio group continued to have disproportionately heavier weight and higher BMI (with the greatest values in those with lower stimulated peak GH concentrations) compared with members of the other two groups, with no salutary effect of GH treatment on weight SDS and a mild improvement in BMI SDS. After S/I treatment, children with Cranio are disproportionately prone to varying degrees of weight gain compared with children with other forms of OGHD. In the present cohort of prepubertal children with Cranio, GH therapy induced excellent linear growth, but failed to have an ameliorative effect on weight gain and had only a slight beneficial effect on BMI gain. Because affected children may have resultant significant long-term medical morbidity and diminished quality of life, it is critical that the mechanism of this phenomenon be determined to devise helpful preventive or therapeutic interventions.

Growth hormone deficiency predicts cardiovascular risk in young adults treated for acute lymphoblastic leukemia in childhood

Acute lymphoblastic leukemia (ALL) is the most common childhood malignancy, and until recently prophylactic cranial radiotherapy (CRT) was important for achieving long-term survival. Hypothalamic-pituitary hormone insufficiency is a well-recognized consequence of CRT for childhood cancer. Another problem is increased cardiovascular risk, which has been shown in long-term survivors of other childhood cancers. In the only previously reported study on cardiovascular risk after childhood ALL, obesity and dyslipidemia were recorded in a small subgroup treated with CRT, compared with patients treated with chemotherapy. The mechanisms behind the increase in cardiovascular risk in survivors of childhood cancer are not clarified. The aim of the present study was to elucidate mechanisms of increased cardiovascular risk in former childhood ALL patients. A group of 44 ALL survivors (23 males, median age 25 yr, range 19-32 yr at the time of study) treated with CRT (median 24 Gy, 18-30 Gy) at a median age of 5 yr (1-18 yr) and chemotherapy were investigated for prevalence of GH deficiency and cardiovascular risk factors. Comparison was made with controls randomly selected from the general population and individually matched for sex, age, smoking habits, and residence. All patients and controls underwent a GHRH-arginine test, and patients with a peak GH 3.9 microg/liter or greater were further investigated with an additional insulin tolerance test. Significantly higher plasma levels of insulin (P = 0.002), blood glucose (P = 0.01), and serum levels of low-density lipoprotein cholesterol, apolipoprotein (Apo) B, triglycerides, fibrinogen, and leptin (all P <or= 0.05) were recorded among the ALL patients, compared with controls. Furthermore, the serum levels of high-density lipoprotein cholesterol (P = 0.03) and Apo A1 (P = 0.005) were significantly lower among the patients. Compared with controls, the patients had higher body mass index and waist to hip ratio, and body composition measured with dual-energy x-ray absorptiometry showed significantly higher fat mass and lower lean mass (P < 0.001). Forty of 44 ALL patients (91%) were considered GH deficient according to the insulin tolerance test and/or the GHRH-arginine test, and the rest were considered GH insufficient. In patients, peak GH during GHRH-arginine was significantly negatively correlated to total body fat mass measured with dual-energy x-ray absorptiometry (r = -0.48, P = 0.001), waist to hip ratio (r = -0.32, P = 0.03), plasma insulin (r = -0.49, P = 0.001), and leptin (r = -0.46, P = 0.002). Moreover, a significantly positive correlation was recorded with high-density lipoprotein cholesterol (r = 0.38, P = 0.012). Using Doppler echocardiography, a marked reduction in cardiac dimensions and performance (ejection fraction P < 0.001 and fractional shortening P = 0.01), compared with controls, was recorded. In conclusion, at a median 17 yr after treatment with CRT and chemotherapy in former childhood ALL patients, a significant increase in cardiovascular risk factors was recorded. We suggest that GH deficiency, induced by CRT, is a primary cause for this because strong correlations between the stimulated GH peak and several of the cardiovascular risk factors were observed.

Is growth hormone deficiency contributing to heart failure in patients with beta-thalassemia major?

A 21-year-old woman with beta-thalassemia major (beta-TM) and GH deficiency developed end-stage heart failure, New York Heart Association (NYHA) functional class IV, within 3 months after withdrawal of recombinant human growth hormone (GH). A myocardial biopsy excluded myocarditis and showed moderate iron deposit in the heart. Before her admission, intensified treatments with digoxin, angiotensin-converting enzyme inhibitor, diuretics and extra chelation therapy (desferrioxamine (DFO)) had not improved her progressive heart failure. At admission, GH was reinstituted together with intensified treatment of cardiac drugs and low doses of DFO, and her heart failure reversed. Four months later, NYHA functional class II was reached and within 1 year her cardiac function was normalised. We suggest that GH deficiency due to iron-induced damage to the hypothalamic-pituitary axis can contribute to heart failure in adult patients with beta-TM.

Long-term improvement of quality of life during growth hormone (GH) replacement therapy in adults with GH deficiency, as measured by questions on life satisfaction-hypopituitarism (QLS-H)

Questions on Life Satisfaction-Hypopituitarism (QLS-H) is a new quality-of-life (QoL) questionnaire developed for adults with hypopituitarism. To determine the effects of long-term GH treatment on QoL, we evaluated QLS-H Z-scores in 576 adult patients with GH deficiency (GHD) enrolled in HypoCCS, an international observational study, using data from five countries in which comparative QLS-H data from the general population were available. Baseline QLS-H Z-scores were significantly lower in GH-deficient patients than in the general population of the same age, gender, and nationality. Z-scores were also significantly lower in female patients vs. males (P = 0.006) and in adult-onset vs. childhood-onset GHD (P = 0.002). Multivariate analysis associated female gender, multiple pituitary hormone deficiencies, low serum IGF-I values (<75 micro g/liter), and concomitant antidepressant medication with low baseline Z-scores. QLS-H Z-scores increased from -1.02 +/- 1.43 (SD) at baseline to -0.25 +/- 1.34 (SD) after 1 yr of GH treatment (P < 0.001) and were no longer significantly different from the general population after 4 yr of treatment. There was no correlation between change in Z-score and GH dose or changes in IGF-I and IGF binding protein-3 during treatment. This study demonstrates that 1) improvements in QoL, as measured by the QLS-H, are maintained during long-term GH replacement therapy of adults with GHD, and 2) the QLS-H is a useful tool for evaluating QoL in hypopituitary patients treated in clinical practice. The authors suggest that evaluation of QoL should be a part of the routine clinical management of adult GH-deficient patients, complementing the measurement of surrogate biological markers or other clinical end points.

Doubled mortality rate in irradiated patients reoperated for regrowth of a macroadenoma of the pituitary gland

BACKGROUND

Reduced life expectancy has been shown in patients with hypopituitarism, mainly caused by cardiovascular diseases. A major cause of hypopituitarism is pituitary adenomas, and radiotherapy may be employed as a treatment modality to reduce the post-operative regrowth rate of these tumours. Recently, we showed that in patients with craniopharyngiomas, tumour regrowth foreshadowed a fourfold risk increase for death. For patients with pituitary adenomas, the impact of regrowth on life expectancy is, however, not known.

OBJECTIVE

To assess the impact of a reoperation due to a regrowth of a pituitary macroadenoma on mortality, taking into account other candidate prognostic factors.

DESIGN AND PATIENTS

In 281 patients with operated and irradiated macroadenomas, excluding acromegaly and Cushing's disease, 35 patients had a regrowth (median follow-up 16.6 years). Possible risk factors for tumour regrowth were investigated by Cox regression models.

RESULTS

For tumour regrowth, age, calendar time at primary surgery, gender and extension of tumour growth had no statistically significant impact. For younger patients, the proportion of regrowths was higher, but after age-stratified Cox regression analysis only regrowth was shown to have a significant impact on mortality, with a more than doubled mortality risk for patients with tumour regrowth as compared with the non-regrowing tumour patients (hazard ratio=2.24, P<0.001). This finding was corroborated by cohort analyses using the general population as an external comparison group.

CONCLUSION

Among patients with irradiated pituitary macroadenomas, excluding acromegaly and Cushing's disease, a doubled mortality rate was observed for those reoperated for tumour regrowth as compared with patients with non-regrowing tumours.