Effect of metformin and insulin vs. placebo and insulin on whole body composition in overweight patients with type 2 diabetes: a randomized placebo-controlled trial.

Some studies indicate potential beneficial effects of metformin on body composition and bone. This trial compared metformin + insulin vs placebo + insulin. Metformin treatment had a small but positive effect on bone quality in the peripheral skeleton, reduced weight gain, and resulted in a more beneficial body composition compared with placebo in insulin-treated patients with type 2 diabetes. INTRODUCTION: Glucose-lowering medications affect body composition. We assessed the long-term effects of metformin compared with placebo on whole body bone and body composition measures in patients with type 2 diabetes mellitus. METHODS: This was a sub-study of the Copenhagen Insulin and Metformin Therapy trial, which was a double-blinded randomized placebo-controlled trial assessing 18-month treatment with metformin compared with placebo, in combination with different insulin regimens in patients with type 2 diabetes mellitus (T2DM). The sub-study evaluates the effects on bone mineral content (BMC), density (BMD), and body composition from whole body dual-energy X-ray absorptiometry (DXA) scans which were assessed at baseline and after 18 months. RESULTS: Metformin had a small, but positive, (p < 0.05) effect on subtotal, appendicular, and legs BMC and BMD compared with placebo. After adjustment for sex, age, vitamin D, smoking, BMI, T2DM duration, HbA1c, and insulin dose, the effects on appendicular BMC and BMD persisted (p < 0.05 for both). The changes in appendicular BMC and BMD corresponded approximately to a 0.7% and 0.5% increase in the metformin group and 0.4% and 0.4% decrease in the placebo group, respectively. These effects were mostly driven by an increase in BMC and BMD in the legs and a loss of BMC and BMD in the arms. During 18 months, all participants increased in weight, fat mass (FM), FM%, and lean mass (LM), but decreased in LM%. The metformin group increased less in weight (subtotal weight (weight-head) - 2.4 [- 3.5, - 1.4] kg, p value < 0.001) and FM (- 1.5 [- 2.3, - 0.8] kg, p value < 0.001) and decreased less in LM% (0.6 [0.2, 1.1] %, p value < 0.001) compared with the placebo group. CONCLUSION: Metformin treatment had a small positive effect on BMC and BMD in the peripheral skeleton and reduced weight gain compared with placebo in insulin-treated patients with T2DM.

The effect of metformin versus placebo in combination with insulin analogues on bone mineral density and trabecular bone score in patients with type 2 diabetes mellitus: a randomized placebo-controlled trial.

Some antihyperglycemic medications have been found to affect bone metabolism. We assessed the long-term effects of metformin compared with placebo on bone mineral density (BMD) and trabecular bone score (TBS) in patients with type 2 diabetes. Metformin had no significant effect on BMD in the spine and hip or TBS compared with a placebo. INTRODUCTION: Patients with type 2 diabetes mellitus (T2DM) have an increased risk of fractures despite a high bone mass. Some antihyperglycemic medications have been found to affect bone metabolism. We assessed the long-term effects of metformin compared with placebo on bone mineral density (BMD) and trabecular bone score (TBS). METHODS: This was a sub-study of a multicenter, randomized, 18-month placebo-controlled, double-blinded trial with metformin vs. placebo in combination with different insulin regimens (the Copenhagen Insulin and Metformin Therapy trial) in patients with T2DM. BMD in the spine and hip and TBS in the spine were assessed by dual-energy X-ray absorptiometry at baseline and after 18 months follow-up. RESULTS: Four hundred seven patients were included in this sub-study. There were no between-group differences in BMD or TBS. From baseline to 18 months, TBS decreased significantly in both groups (metformin group, - 0.041 [- 0.055, - 0.027]; placebo group - 0.046 [- 0.058, - 0.034]; both p < 0.001). BMD in the spine and total hip did not change significantly from baseline to 18 months. After adjustments for gender, age, vitamin D, smoking, BMI, duration of T2DM, HbA1c, and insulin dose, the TBS between-group differences increased but remained non-significant. HbA1c was negatively associated with TBS (p = 0.009) as was longer duration of diabetes, with the femoral neck BMD (p = 0.003). Body mass index had a positive effect on the hip and femoral neck BMD (p < 0.001, p = 0.045, respectively). CONCLUSIONS: Eighteen months of treatment with metformin had no significant effect on BMD in the spine and hip or TBS in patients with T2DM compared with a placebo. TBS decreased significantly in both groups. TRIAL REGISTRATION: ClinicalTrials.gov (NCT00657943).

Study rationale and design of the CIMT trial: the Copenhagen Insulin and Metformin Therapy trial.

BACKGROUND: Patients with type 2 diabetes (T2DM) have an increased mortality rate primarily because of macrovascular disease. Where T2DM patients cannot be managed sufficiently through diet, exercise and peroral antidiabetic drugs, that is when haemoglobin A1c (HbA1c) is above 7.0%, it is yet unknown whether a combination of metformin and insulin analogues is superior to insulin analogues alone. Nor is it known which insulin analogue regimen is the optimal. OBJECTIVE: The primary objective of this trial is to evaluate the effect of an 18-month treatment with metformin vs. placebo in combination with one of three insulin analogue regimens, the primary outcome measure being carotid intima-media thickness (CIMT) in T2DM patients. DESIGN: A randomized, stratified, multicentre trial having a 2 x 3 factorial design. The metformin part is double masked and placebo controlled. The insulin treatment is open. The intervention period is 18 months. PATIENT POPULATION: Nine hundred and fifty patients with T2DM and HbA1c > or = 7.5% on treatment with oral hypoglycaemic agents or on insulin treatment and deemed able, by the investigator, to manage once-daily insulin therapy with a long-acting insulin analogue. RANDOMIZATION: Central randomization stratified for age (above 65 years), previous insulin treatment and treatment centre. INTERVENTIONS: Metformin 1 g x two times daily vs. placebo (approximately 475 patients vs. 475 patients) in combination with insulin detemir before bedtime (approximately 315 patients) or biphasic insulin aspart 30 before dinner with the possibility to increase to two or three injections daily (approximately 315 patients) or insulin aspart before the main meals (three times daily) and insulin detemir before bedtime (approximately 315 patients). Intervention follows a treat-to-target principle in all six arms aiming for an HbA1c < or = 7.0%. OUTCOME MEASURES: Primary outcome measure is the change in CIMT from baseline to 18 months. Secondary outcome measures comprises the composite outcome of death, acute myocardial infarction, stroke or amputation assessed by an adjudication committee blinded to intervention, other cardiovascular clinical outcomes, average postprandial glucose increment from 0 to 18 months, hypoglycaemia and any inadvertent medical episodes. In addition, change in plaque formation in the carotids, HbA1c, cardiovascular biomarkers, body composition, progression of microvascular complications and quality of life will be assessed as tertiary outcome measures. TIME SCHEDULE: Patient enrolment started May 2008. Follow-up is expected to finish in March 2011. CONCLUSION: CIMT is designed to provide evidence as to whether metformin is advantageous even during insulin treatment and to provide evidence regarding which insulin analogue regimen is most advantageous with regard to cardiovascular disease.

Skin morphological changes in growth hormone deficiency and acromegaly.

OBJECTIVE: To evaluate the histomorphology of skin and its appendages, especially eccrine sweat glands, in patients with GH disorders, because reduced sweating ability in patients with growth hormone deficiency (GHD) is associated with increased risk of hyperthermia under stressed conditions. DESIGN AND METHODS: A skin biopsy was obtained from 17 patients with GHD treated with GH, five patients with untreated GHD, 10 patients with active acromegaly and 13 healthy controls. RESULTS: The sweat secretion rate (SSR) was significantly decreased in both the untreated (median 41 mg/30 min, range 9-79 mg/30 min) and the GH-treated (median 98 mg/30 min, range 28-147 mg/30 min) patients with GHD compared with that in controls (median 119 mg/30 min, range 90-189 mg/30 min; P=0.001 and 0.01 respectively). Epidermal thickness was significantly decreased in both untreated (median 39 microm, range 28-55 microm) and GH-treated patients with GHD (median 53 microm, range 37-100 microm), compared with that in controls (median 66 microm, range 40-111 microm; P<0.02). A statistically non-significant tendency towards thinner epidermis (median 59 microm, range 33-83 microm) was recorded in acromegalic patients (P=0.08) compared with controls. There was no significant difference in the area of the sebaceous glands in the biopsies between the three groups and the controls. The area of eccrine sweat gland glomeruli was significantly decreased in the untreated patients with GHD (median 16407 microm2, range 12758-43976 microm2) compared with that in controls (median 29446 microm2, range 13511-128661 microm2; P=0.03), but there was no significant difference between the GH-treated patients with GHD and controls. CONCLUSIONS: We conclude that GH, either directly or via IGF-I, may have both a structural and a functional effect on human skin and its appendages, and that patients with GHD have histomorphological changes in skin compared with controls. Importantly, these changes are not fully reversed despite long-term and adequate GH treatment in patients with childhood onset GHD.

Total and free insulin-like growth factor I, insulin-like growth factor binding protein 3 and acid-labile subunit reflect clinical activity in acromegaly.

The aim was to evaluate, markers of disease activity in acromegaly in relation to perceived disease activity. Thirty-seven consecutively treated, acromegalic patients, classified by clinical symptoms as inactive (n=16), slightly active (n=10) and active (n=11), entered the study. When evaluating the inactive and the active groups, we found that positive and negative predictive values (PV(pos), PV(neg)) for clinical disease activity of total and free insulin-like growth factor-I (IGF-I) were 0.59, 0.90 and 1.00, 0.82 respectively. Acid-labile subunit (ALS) showed diagnostic merit similar to insulin-like growth factor binding protein-3 (IGFBP-3) with PV(pos) of 0.69 and 0.71 and PV(neg) of 0.91 and 0.92 respectively. We conclude that free IGF-I is more closely related than total IGF-I to perceived disease activity and is as such useful when evaluating previously treated acromegaly for disease activity. Total IGF-I, IGFBP-3 and ALS possess a higher PV(neg) for the clinical disease activity. None of the parameters can at present be claimed to be superior to the others and thus all the measured parameters are recommended to be part of the evaluation of acromegalic patients.

Consequences of stopping growth hormone (GH) therapy in young GH deficient patients with childhood onset disease.

Many studies have shown the beneficial, anabolic effects of growth hormone (GH) replacement therapy in GH deficient adults with childhood onset or adult onset disease. It is becoming increasingly evident, however, that these two groups of patients differ in many respects. Patients with adult onset GH deficiency represent fully developed individuals who have various organic, cerebral defects. By contrast, patients with childhood onset disease represent a heterogenous group comprising individuals with conditions, such as idiopathic isolated GH deficiency, genetic defects and organic defects. It is generally accepted that all children treated with GH should be retested in adulthood before adult replacement is started, as around 40% have a normal retest. It is unclear whether continued treatment with GH in childhood onset GH deficiency will yield results as positive as those seen in trials where GH is re-instituted after longer periods without treatment. Similarly, it is unknown at what timepoint cessation of GH treatment will cause a worsening in the physical state of the patient. In our placebo-controlled trial where GH was discontinued in 19 patients treated with GH during childhood, we determined exercise capacity, body composition, muscle mass and strength, cardiac function, sweating capacity, thyroid function and glucose metabolism before and after 12 months of continued treatment with GH.

[TPO immunostaining of the solitary, cold thyroid nodules]. / TPO-immunfarvning af den solitaere, kolde thyreoideaknude.

INTRODUCTION: The chance of malignancy in scintigraphically cold thyroid nodules is 2-24%. Differentiation between malignant and benign cytology is difficult. The aim of this study was to evaluate the ability of immunostaining (MoAB47--raised against thyroid peroxidase (TPO)) to differentiate between malignant and benign cells taken from cold thyroid nodules by fine needle aspiration biopsy (FNAB) in order to reduce the number of unnecessary thyroid operations. MATERIALS AND METHODS: One hundred and eighty-one patients (150 female) with a scintigraphically cold, solitary thyroid nodule were entered between 1993 and 1996. Fifty-seven were excluded for various reasons. Material removed by FNAB was stained with MoAB47 and routine staining. Staining of 80% or more of the cells was considered benign, less than 80% was considered malignant. Routine staining of operatively removed material was used as the final diagnosis. RESULTS: A pattern with negative TPO staining was found in all lesions that were subsequently proved to be malignant. In all but one, the lesions subsequently diagnosed as being benign stained positive for TPO. The sensitivity and specificity were respectively 1.0 and 0.99. CONCLUSION: TPO immunostaining of material removed by FNAB is a powerful tool in the differentiation between benign and malignant tumours.

Immune function during GH treatment in GH-deficient adults: an 18-month randomized, placebo-controlled, double-blinded trial.

OBJECTIVE: The aim of the present study was to investigate natural killer (NK) cell function and lymphocyte subsets in GH-deficient (GHD) adults, before and during long-term GH treatment. STUDY DESIGN: We investigated immune function in 19 adults with severe GHD, before and during 18 months of randomized treatment with GH or placebo. Measurement of lymphocyte subsets and NK cell activity was performed. Data obtained from 110 healthy adults served as reference values. RESULTS: NK cell activity, both unstimulated and stimulated by interferon-a or interleukin-2, was significantly impaired in GHD patients. Similarly, NK cell concentration and the proportion of NK cells (CD16+) were reduced in GHD patients compared to controls. Both total and proportional CD4 + cells were increased in patients compared with controls. IGF-I increased significantly during treatment, but the immune functions investigated were unaltered. CONCLUSIONS: GH deficiency was associated with changes in lymphocyte subsets and impaired unstimulated and stimulated natural killer cell activity, but these remained abnormal during 18 months of GH replacement therapy. Extra-pituitary GH gene expression in, e.g. lymphoid tissues may serve as an autocrine/paracrine factor in immunomodulation and explain the clinical normal immune function in adult GH-deficient patients.

Sweat secretion rates in growth hormone disorders.

BACKGROUND: While increased sweating is a prominent symptom in patients with active acromegaly, reduced sweating is gaining status as part of the growth hormone deficiency (GHD) syndrome. DESIGN AND SUBJECTS: Sweat secretion rate (SSR), as measured by pilocarpine iontophoresis represents the maximal capacity for stimulated sweat secretion in a localized skin area. SSR was studied in 37 patients with a history of acromegaly, 20 adult patients with GHD before and during long-term GH substitution of GHD adults, and 58 control subjects. RESULTS: Acromegaly: Patients with acromegaly had significantly higher SSR than healthy controls (Z-score + 1.9 (+/- 1.1) mean (+/- SD) (P < 0.001)). SSR was increased irrespective of current clinical disease activity. Thus, the SSR Z-scores in 16 clinically inactive patients were + 2.1 (+/- 1.2), in 10 slightly or doubtfully active patients + 1.5 (+/- 0.7) and in 11 active patients + 1.8 (+/- 1.3). There was no correlation between SSR and IGF-I. GHD: Twenty adult patients participated in an 18-month randomised, placebo controlled, double blinded study of physiological dose GH substitution, followed by 18 months of open GH treatment. SSR at baseline was reduced in male but not in female GHD patients. Mean SSR (95% confidence interval) for 11 male patients was 89.0 mg/30 minutes (51.9-126.1) as compared to 133.5 mg/30 minutes (59.2-259.9) (P = 0.01) in 24 male controls, and for 11 female patients 48.2 mg/30 minutes (25.9-70.6) as compared to 49.2 mg/30 minutes (12.6-93. 9) in 34 female controls. GH treatment in physiological substitution doses for up to 36 months had no effect on SSR. CONCLUSION: We have demonstrated that longstanding GH hypersecretion in patients with acromegaly induces irreversible changes of sweat gland function, with persistently elevated SSR despite treatment and clinical cure. In GHD patients, SSR was reduced in males but not in females, which together with the established gender difference in normal controls emphasises the role of androgen deficiency as a cofactor for reduced sweating in hypopituitary patients. Sweat gland development seems to be more susceptible to lack of hormones in childhood and adolescence than in adulthood, whereas growth hormone excess can modify sweat function later in life.

Thyroperoxidase (TPO) immunostaining of the solitary cold thyroid nodule.

OBJECTIVE: To evaluate the value of immunostaining using the monoclonal antibody (MoAB47) against thyroperoxidase (TPO) in distinguishing between benign and malignant tumour cells in fine needle aspiration cytology (FNAC) samples obtained from a solitary cold nodule of the thyroid gland for the purpose of strengthening the indication for thyroid surgery. DESIGN: A prospective, immunocytochemical study of FNACs taken from patients with solitary cold thyroid nodules who presented to Rigshospitalet, Copenhagen, Denmark, during the period April 1993 to May 1996. The first sample series was taken perioperatively in order to test the utility of the method. In the second part of the study samples were obtained preoperatively by ultrasonic guided aspiration. Tissue sections from the nodules obtained during a subsequent operation served as controls. PATIENTS: One hundred and eighty-one patients, 150 women and 31 men, were studied. The age range was 14-89 years with a median age of 44 years. Fifty-seven patients were excluded from the study for various reasons leaving us with a total of 124 nodules from 124 patients for final evaluation. METHODS: FNAC cells and corresponding nodular tissue were stained by immunocyto- and immuno-histochemistry using MoAb47 and by routine staining methods. Samples were considered benign if 80% or more of the epithelial-looking cells of both the FNACs and the histological tissue sections of the nodule were stained by TPO. Consequently, samples were considered malignant if more than 20% of the epithelial-looking cells failed to stain for TPO. Routinely stained tissue cells and sections served as diagnostic controls. RESULTS: A pattern with negative TPO staining was found in all lesions which, by conventional histological staining, were subsequently proven to be malignant. A universal and reliable, positive TPO staining pattern was found in all subsequently proven benign lesions, with the exception of one out of 26 follicular adenomas. This gave the method a sensitivity of 1.0 (negative TPO staining = malignancy in 27 out of 27) and a specificity of 0.99 (positive TPO staining = benign lesion, in 96 out of 97). Positive and negative predictive values were 0.96 and 1.00 respectively. CONCLUSION: Thyroperoxidase immunostaining of fine needle aspirates from solitary, scintigraphically cold nodules of the thyroid gland has proved to be an important and reliable diagnostic tool for distinguishing between benign and malignant nodules. Thus, patients might be spared further surgery if not otherwise indicated.