Evaluation of treated acromegalic patients with normal growth hormone levels during oral glucose load

1984 ◽  
Vol 107 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Max Rieu ◽  
Jean-Marc Kuhn ◽  
Henri Bricaire ◽  
Jean-Pierre Luton

Abstract. Twenty-one treated acromegalics with plasma GH levels ≤ 5 ng/ml were evaluated during an oral glucose tolerance test (OGTT). Serum insulin-like growth factor (IGF) levels, measured by a competitive binding assay, were high in 10, normal in 8 and low in 3 patients. Urinary calcium excretion (Ca U), measured over 24 h, was elevated in 9 of the 10 patients whose IGF levels were high, whereas only 1 of the patients with normal or low IGF levels was hypercalciuric. A paradoxical rise in GH following TRH injection was observed in 5 of the 10 patients whose IGF levels were high, whereas all patients with normal or low IGF levels showed no GH response to TRH. GH levels ≥ 10 ng/ml occurred during ornithine (ORN) administration in 6 of the 18 patients with normal or high IGF levels. The remaining 12 patients with no GH rise during ORN included 2 cases in which IGF levels were high and GH rose following TRH, and 2 cases in which IGF levels were normal and GH levels were ≥ 10 ng/ml during insulin-induced hypoglycaemia (IIH), thus excluding a GH deficiency. These results show that acromegaly is not cured in certain treated patients with normal GH levels during OGTT. It seems that IGF and Ca U determinations are valuable indices of activity, in contrast to GH response to ORN. The GH response to TRH is also relatively useful.

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 2158-2158
Author(s):  
Mohamed A. Yassin ◽  
Ahmed M Elawa ◽  
Ashraf T Soliman

Abstract Abstract 2158 Introduction: Both insulin deficiency and insulin resistance are reported in patients with β thalassemia major (BTM). The use of continuous blood glucose monitoring system (CGMS) among the different methods for early detection of glycaemic abnormalities has not been studied thoroughly in these patients. Aims: The aims of this study were: 1. to detect glycaemic abnormalities, if any, in young adults with BTM using fasting blood glucose (FBG), oral glucose tolerance test (OGTT), 72-h continuous glucose concentration by CGMS system, and serum insulin and C-peptide concentrations 2. To compare the results of these two methods in detecting glycaemic abnormalities in these patients and 3. To calculate homeostatic model assessment (HOMA), and the quantitative insulin sensitivity check index (QUICKI) in these patients. In order to evaluate whether glycaemic abnormalities are due to insulin deficiency and/or resistance. Materials and methods: Randomly selected young adults (n = 14) with BTM were the subjects of this study. All patients were investigated using a standard oral glucose tolerance test (OGTT) (using 75 gram of glucose) and 72-h continuous glucose concentration by CGM system (Medtronic system). Fasting serum insulin and C-peptide concentrations were measured and HOMA-B, HOMA-IR were calculated accordingly. Results: Using OGTT, 5 patients had impaired fasting glucose (IFG) (Fasting BG from 5.6 to 6.9 mmol/L). Two of them had impaired glucose tolerance IGT (BG from 7.8 and < 11.1 mmol/L) and one had BG = 16.2 mmol/L after 2-hrs (diabetic). Using CGMS in addition to the glucose data measured by glucometer (3–5 times/ day), 6 patients had IFG. The maximum (postprandial) BG recorded exceeded 11.1 mmol/L in 4 patients (28.5%) (Diabetics) and was > 7.8 but < 11.1 mmol/L in 8 patients (57%) (IGT). The mean values of HOMA and QUICKI in patients with BTM were < 2.6 (1.6± 0.8) and > 0.33 (0.36±0.03) respectively ruling out significant insulin resistance in these adolescents. There was a significant negative correlation between the β-cell function (B %) on the one hand and the fasting and the 2-h BG (r= −0.6, and − 0.48, P< 0.01 respectively) on the other hand. Serum insulin concentrations were not correlated with fasting BG or ferritin levels. The average and maximum BG levels recorded by CGMS were significantly correlated with the fasting BG (r= 0.69 and 0.6 respectively with P < 0.01) and with the BG at 2-hour after oral glucose intake (r= 0.87and 0.86 respectively with P < 0.01). Ferritin concentrations were positively correlated with the fasting BG and the 2-h BG levels in the OGTT (r= 0.69, 0.43 respectively, P < 0.001) as well as with the average and the maximum BG recorded by CGM (r =0.75, and 0.64 respectively with P < 0.01). Ferritin concentrations were negatively correlated with the β-cell function (r= −0.41, P< 0.01). Conclusion: CGMS has proved to be superior to OGTT for the diagnosis of glycaemic abnormalities in young adult patients with BTM. In our patients, defective β-cell function rather than insulin resistance appeared to be the cause for these abnormalities. The significant correlations between serum ferritin concentrations and the beta cell functions suggested the importance of adequate chelation to prevent β-cell dysfunction Disclosures: No relevant conflicts of interest to declare.


1967 ◽  
Vol 37 (4) ◽  
pp. 443-453 ◽  
Author(s):  
IRIS M. TRAYNER ◽  
T. A. WELBORN ◽  
A. H. RUBENSTEIN ◽  
T. RUSSELL FRASER

SUMMARY As measured both by immunoassay and bioassay during a glucose tolerance test (50 g.) on ten subjects in the third trimester of pregnancy, the serum insulin levels fasting, 1 and 2 hr. after glucose were raised at least threefold compared with the levels in 23 non-pregnant women. The renal clearance of immunoassayable insulin was lower than that in the non-pregnant state (the mean in the pregnant subjects was 0·18 ml./min. compared with 0·45 ml./min. in the normal non-pregnant subjects). In the same subjects the mean serum non-suppressible insulin-like activity, which is unaltered by oral glucose, was 1·5 times higher than the non-pregnant mean level, but this difference was not significant. Four pregnant latent diabetics, tested similarly in the latter part of pregnancy, showed even higher fasting serum insulin levels than the normal pregnant subjects, but a lessened response to the same glucose load.


2007 ◽  
Vol 98 (3) ◽  
pp. 556-562 ◽  
Author(s):  
Mark J. Dekker ◽  
Jenny E. Gusba ◽  
Lindsay E. Robinson ◽  
Terry E. Graham

Acute caffeine ingestion increases serum NEFA and plasma adrenaline and decreases insulin sensitivity. Although frequently suggested, it is not known if a tolerance to these alterations in glucose homeostasis is developed in habitual caffeine consumers. Our objective was to determine whether acute caffeine ingestion continued to alter insulin, glucose, NEFA and adrenaline during an oral glucose tolerance test (OGTT) following 14 d of caffeine consumption. Twelve caffeine-naive young males underwent four OGTTs over a 4-week period. Subjects ingested a gelatin-filled placebo (PLA) capsule on the first trial day and 5 mg caffeine/kg body weight on the remaining three trial days (day 0, day 7, day 14) before a 2 h OGTT. Following day 0 and day 7, subjects were given six dosages of 5 mg caffeine/kg to consume per d between trials. Serum insulin and blood glucose area under the curve (AUC) were significantly elevated (P < 0·05) v. PLA on day 0 (36 and 103 %, respectively) and were not different from PLA on day 7. On day 14, insulin AUC was 29 % greater than PLA (P < 0·05), and glucose was greater (P < 0·05) during the first hour, although the 50 % elevation in glucose AUC was not different from PLA. Before the OGTT, caffeine resulted in greater (P < 0·05) serum NEFA and plasma adrenaline concentrations in all three caffeine trials, but both NEFA and adrenaline concentrations were decreased (P < 0·05) on day 14 v. day 0. Although 14 d of caffeine consumption by previously caffeine-naive subjects reduced its impact on glucose homeostasis, carbohydrate metabolism remained disrupted.


2007 ◽  
Vol 92 (1) ◽  
pp. 229-234 ◽  
Author(s):  
Won Hah Park ◽  
Yoo Joung Oh ◽  
Gae Young Kim ◽  
Sang Eun Kim ◽  
Kyung-Hoon Paik ◽  
...  

Abstract Context: Obestatin is a peptide hormone derived from the proteolytic cleavage of ghrelin preprohormone. In Prader-Willi syndrome (PWS), the levels of total ghrelin (TG) and acylated ghrelin (AG) are increased, and these hormones are regulated by insulin. Objective: Our objective was to analyze the changes in the obestatin levels after glucose loading and to characterize the correlations of obestatin with TG, AG, and insulin. Design: Plasma obestatin, TG, AG, and insulin levels were measured in PWS children (n = 15) and controls (n = 18) during an oral glucose tolerance test. Setting: All subjects were admitted to the Samsung Medical Center. Interventions: An oral glucose tolerance test was performed after an overnight fast. Main Outcome Measures: The plasma levels of obestatin, TG, AG, and serum insulin were measured at 0, 30, 60, 90, and 120 min after glucose challenge, and areas under the curves (AUCs) were calculated. Results: No significant difference in AUC of the plasma obestatin was found between the PWS children and normal obese controls (P = 0.885), although AUC of AG (P = 0.002) and TG (P = 0.003) were increased in the PWS children. Moreover, There was a negative correlation between the AUC of AG and AUC of insulin both in PWS (r = −0.432; P = 0.049) and in controls (r = −0.507; P = 0.016). However, AUC of obestatin was not significantly correlated with AUC of insulin (in PWS, r = 0.168 and P = 0.275; in controls, r = −0.331 and P = 0.09). Conclusions: Our results indicate that plasma obestatin is not elevated in PWS children and is not regulated by insulin both in PWS children and in obese controls.


1994 ◽  
Vol 39 (3) ◽  
pp. 71-73
Author(s):  
C. Bengtsson ◽  
L. Lapidus

Felodipine,1 a vascular selective antihypertensive calcium antagonist, was compared with hydrochlorothiazide, a diuretic, with respect to glucose tolerance. An open crossover study was performed comprising 16 non-diabetic hypertensive women (age range 59–75 years). The women continued to take a beta-blocker as a basal therapy. Each treatment period lasted three months. The blood pressure was similar irrespective of treatment. Blood glucose values were not significantly different during the oral glucose tolerance test. Serum insulin levels after glucose administration were lower when the patients were treated with felodipine than when taking hydrochlorothiazide. A possible explanation for this observation may be an increased insulin release as a consequence of treatment with a diuretic in order to maintain normal blood glucose levels during the glucose tolerance test. Felodipine appears preferable to hydrochlorothiazide as an addition to a beta blocker in hypertensive patients from a glucose metabolism point of view.


1978 ◽  
Vol 88 (1) ◽  
pp. 18-22 ◽  
Author(s):  
A. D. B. Harrower ◽  
N. McD. Davidson ◽  
P. L. Yap ◽  
I. M. Nairn ◽  
J. A. Fyffe ◽  
...  

ABSTRACT Insulin tolerance tests were carried out in 10 acromegalic patients after 1 mg dexamethasone had been given the previous evening (DEX-ITT). Nine patients showed a rise in plasma 11-OHCS and four patients showed a rise in plasma growth hormone (GH) levels. These responses were unaltered after treatment with bromocriptine 10 mg daily for two months. Basal plasma GH levels fell in 6 of the patients and the mean plasma GH levels of the 10 patients during an oral glucose tolerance test (OGTT) fell from 63.2 ± 25.5 ng/ml before treatment to 53.0 ± 27.1 ng/ml (mean ± sem; P < 0.05). These data fail to confirm a previous report of abnormal hypothalmic-pituitary-adrenal suppressibility during a DEX-ITT in acromegalic patients. They also indicate that bromocriptine does not alter the responses of plasma 11-OHCS and plasma GH to the DEX-ITT despite lowering plasma GH levels.


2001 ◽  
Vol 79 (7) ◽  
pp. 559-565 ◽  
Author(s):  
Terry E Graham ◽  
Premila Sathasivam ◽  
Mary Rowland ◽  
Natasha Marko ◽  
Felicia Greer ◽  
...  

We tested the hypothesis that caffeine ingestion results in an exaggerated response in blood glucose and (or) insulin during an oral glucose tolerance test (OGTT). Young, fit adult males (n = 18) underwent 2 OGTT. The subjects ingested caffeine (5 mg/kg) or placebo (double blind) and 1 h later ingested 75 g of dextrose. There were no differences between the fasted levels of serum insulin, C peptide, blood glucose, or lactate and there were no differences within or between trials in these measures prior to the OGTT. Following the OGTT, all of these parameters increased (P [Formula: see text] 0.05) for the duration of the OGTT. Caffeine ingestion resulted in an increase (P [Formula: see text] 0.05) in serum fatty acids, glycerol, and plasma epinephrine prior to the OGTT. During the OGTT, these parameters decreased to match those of the placebo trial. In the caffeine trial the serum insulin and C peptide concentrations were significantly greater (P [Formula: see text] 0.001) than for placebo for the last 90 min of the OGTT and the area under the curve (AUC) for both measures were 60 and 37% greater (P [Formula: see text] 0.001), respectively. This prolonged, increased elevation in insulin did not result in a lower blood glucose level; in fact, the AUC for blood glucose was 24% greater (P = 0.20) in the caffeine treatment group. The data support our hypothesis that caffeine ingestion results in a greater increase in insulin concentration during an OGTT. This, together with a trend towards a greater rather than a more modest response in blood glucose, suggests that caffeine ingestion may have resulted in insulin resistance.Key words: adenosine, skeletal muscle, methylxanthines, glucose uptake, diabetes.


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