Evaluating potential predictors of weight loss response to liraglutide in adolescents with obesity: A post hoc analysis of the randomized, placebo-controlled SCALE Teens trial

BACKGROUND

As childhood obesity prevalence increases, determining which patients respond to anti-obesity medications would strengthen personalized approaches to obesity treatment. In the SCALE Teens trial among pubertal adolescents with obesity (NCT02918279), liraglutide 3.0 mg (or maximum tolerated dose) significantly reduced body mass index (BMI) standard deviation score on average versus placebo. That said, liraglutide effects on BMI reduction varied greatly among adolescents, similar to adults.

OBJECTIVES

To identify post hoc characteristics predictive of achieving ≥5% and ≥10% BMI reductions at 56 weeks with liraglutide versus placebo in adolescents from the SCALE Teens trial.

METHODS

Logistic regression analysis was performed in 251 adolescents treated with liraglutide (n = 125) or placebo (n = 126) for 56 weeks. Baseline characteristics (selected a priori) included sex, race, ethnicity, age, Tanner (pubertal) stage, glycemic status (hyperglycemia [type 2 diabetes/prediabetes] vs. normoglycemia), obesity category (Class II/III vs. I), severity of depression symptoms (Patient Health Questionnaire-9), and weight variability (weight fluctuations over time). The effects of early responder status (≥4% BMI reduction at week 16) on week 56 response were assessed using descriptive statistics.

RESULTS

Baseline characteristics did not affect achievement of ≥5% and ≥10% BMI reductions at week 56 in adolescents treated with liraglutide. Further, there was no association between weight variability and BMI reduction. Early liraglutide responders appeared to have greater BMI and body weight reductions at week 56 compared with early non-responders.

CONCLUSIONS

This secondary analysis suggests that adolescents with obesity may experience significant BMI reductions after 56 weeks of liraglutide treatment, regardless of their sex, race, ethnicity, age, pubertal stage, glycemic status, obesity category, severity of depression symptoms, or weight variability. Early response may predict greater week 56 response.

Liraglutide for Weight Management in Children and Adolescents With Prader-Willi Syndrome and Obesity

CONTEXT

Prader-Willi syndrome (PWS) is characterized by lack of appetite control and hyperphagia, leading to obesity. Pharmacological options for weight management are needed.

OBJECTIVE

To determine whether liraglutide treatment for weight management is superior to placebo/no treatment in pediatric individuals with PWS.

METHODS

This was a multicenter, 52-week, placebo-controlled trial with a 16-week double-blinded period. Adolescents (n = 31, aged 12-17 years; Tanner stage 2-5) and children (n = 24, aged 6-11 years; Tanner stage <2) with PWS and obesity were included. Patients were randomized 2:1 to liraglutide 3.0 mg (or maximum-tolerated dose) or placebo for 16 weeks, after which placebo was stopped. Liraglutide was continued for 52 weeks. All patients followed a structured diet and exercise program throughout the trial. The coprimary endpoints were change in body mass index (BMI) standard deviation score (SDS) from baseline to 16 and 52 weeks. Secondary endpoints included other weight-related parameters, hyperphagia, and safety.

RESULTS

Change in BMI SDS from baseline to weeks 16 and 52 was not significantly different between treatments in adolescents (estimated treatment difference: -0.07 at week 16 and -0.14 at week 52) and children (-0.06 and -0.07, respectively). Changes in other weight-related parameters between treatments were not significant. At week 52, hyperphagia total and drive scores were lower in adolescents treated with liraglutide vs no treatment. The most common adverse events with liraglutide were gastrointestinal disorders.

CONCLUSION

Although the coprimary endpoints were not met, changes in hyperphagia total and drive scores in adolescents warrant further studies on liraglutide in this population.

Liraglutide pharmacokinetics and exposure-response in adolescents with obesity

BACKGROUND

Obesity in adolescence presents a major public health challenge, often leading to obesity in adulthood with associated chronic disease.

OBJECTIVES

This study aimed to perform a population pharmacokinetic and exposure-response analysis of liraglutide by meta-analysis of data from trials conducted in children, adolescents and adults with obesity.

METHODS

The population pharmacokinetic analysis investigated the effect of covariates body weight, age group (children, adolescents and adults) and sex on liraglutide exposure in adolescents compared with previous results in adults. The exposure-response relationship of liraglutide for the change from baseline in body mass index standard deviation score (BMI SDS) was evaluated in adolescents and compared to that in adults.

RESULTS

Body weight was the main covariate affecting liraglutide exposure, with lower exposures at higher body weights, whereas age group was of no importance and sex was of little importance. An exposure-response relationship was demonstrated for liraglutide in both adolescents and adults as the decrease in BMI SDS from baseline increased in an exposure-dependent manner with increasing liraglutide exposure.

CONCLUSIONS

The population pharmacokinetic analysis supported similar liraglutide exposures in adolescents and adults; body weight was the most important covariate affecting exposure. An exposure-response relationship was established for liraglutide.

Effect of liraglutide treatment on body mass index and weight parameters in children and adolescents with type 2 diabetes: Post hoc analysis of the ellipse trial

BACKGROUND

Weight loss in children and adolescents with type 2 diabetes (T2D) is associated with improved glycaemic control.

OBJECTIVES

To assess the effects of liraglutide vs placebo on body mass index (BMI) and weight parameters in children and adolescents with T2D using data from the ellipse trial (NCT01541215).

METHODS

The ellipse trial randomized participants (10-<17 years old, BMI >85th percentile, T2D, glycated haemoglobin [HbA_1c ] 7.0%-11.0% [if diet- and exercise-treated] or 6.5% to 11.0% [if treated with metformin, basal insulin or both]) to liraglutide or placebo. This post-hoc analysis evaluated changes from baseline to weeks 26 and 52 in absolute BMI, percent change in BMI and other weight-related parameters. Changes were assessed by liraglutide overall (all doses) and liraglutide by dose (0.6, 1.2 and 1.8 mg/day) vs placebo using a pattern mixture model of observed data, with missing observations imputed from each treatment group.

RESULTS

In total, 134 participants were included. There were statistically significant differences between groups in certain parameters, including absolute BMI (estimated treatment difference [ETD] -0.89 kg/m² ; 95% confidence interval [CI] -1.71,-0.06) and percent change in BMI (ETD -2.73%; 95% CI -5.15,-0.30) at week 52, but none at week 26. Dose-dependent effects were not observed for liraglutide vs placebo for all BMI/weight parameters.

CONCLUSIONS

Compared with placebo, liraglutide was associated with statistically significant reductions in BMI/weight parameters at week 52, but not week 26, in children and adolescents with T2D.

Liraglutide pharmacokinetics and exposure-response in pediatric patients with type 2 diabetes

Objectives Based on the ellipse trial, liraglutide was recently approved for use in pediatric patients with type 2 diabetes. We report the comparative exposure of liraglutide in pediatric vs. adult patients. Methods In this pharmacokinetic (PK) and exposure-response meta-analysis, data from two pediatric trials (including ellipse) and two adult trials of liraglutide were compiled (1,137 PK observations from 116 patients) to determine the impact of body weight, age and sex on liraglutide exposure. The exposure-response relationship for glycated hemoglobin (HbA1c) and body weight was compared between pediatric and adult patients. Additionally, the relationships between exposure and change from baseline in body mass index (BMI) and BMI standard deviation score (SDS) were assessed. Results The same liraglutide dose showed comparable exposure levels in pediatric and adult patients. Body weight and sex were the most important covariates for liraglutide exposure. There was an increasing response with higher liraglutide concentrations, and greater reductions were observed from baseline in HbA1c at 26 weeks vs. placebo. A trend toward lower body weight, BMI and BMI SDS was observed at 26 weeks. Conclusions These results support use of the same liraglutide dosing regimen in children and adolescents, aged ≥10 years, as that used in adults.

A Randomized, Controlled Trial of Liraglutide for Adolescents with Obesity

BACKGROUND

Obesity is a chronic disease with limited treatment options in pediatric patients. Liraglutide may be useful for weight management in adolescents with obesity.

METHODS

In this randomized, double-blind trial, which consisted of a 56-week treatment period and a 26-week follow-up period, we enrolled adolescents (12 to <18 years of age) with obesity and a poor response to lifestyle therapy alone. Participants were randomly assigned (1:1) to receive either liraglutide (3.0 mg) or placebo subcutaneously once daily, in addition to lifestyle therapy. The primary end point was the change from baseline in the body-mass index (BMI; the weight in kilograms divided by the square of the height in meters) standard-deviation score at week 56.

RESULTS

A total of 125 participants were assigned to the liraglutide group and 126 to the placebo group. Liraglutide was superior to placebo with regard to the change from baseline in the BMI standard-deviation score at week 56 (estimated difference, -0.22; 95% confidence interval [CI], -0.37 to -0.08; P = 0.002). A reduction in BMI of at least 5% was observed in 51 of 113 participants in the liraglutide group and in 20 of 105 participants in the placebo group (estimated percentage, 43.3% vs. 18.7%), and a reduction in BMI of at least 10% was observed in 33 and 9, respectively (estimated percentage, 26.1% vs. 8.1%). A greater reduction was observed with liraglutide than with placebo for BMI (estimated difference, -4.64 percentage points) and for body weight (estimated difference, -4.50 kg [for absolute change] and -5.01 percentage points [for relative change]). After discontinuation, a greater increase in the BMI standard-deviation score was observed with liraglutide than with placebo (estimated difference, 0.15; 95% CI, 0.07 to 0.23). More participants in the liraglutide group than in the placebo group had gastrointestinal adverse events (81 of 125 [64.8%] vs. 46 of 126 [36.5%]) and adverse events that led to discontinuation of the trial treatment (13 [10.4%] vs. 0). Few participants in either group had serious adverse events (3 [2.4%] vs. 5 [4.0%]). One suicide, which occurred in the liraglutide group, was assessed by the investigator as unlikely to be related to the trial treatment.

CONCLUSIONS

In adolescents with obesity, the use of liraglutide (3.0 mg) plus lifestyle therapy led to a significantly greater reduction in the BMI standard-deviation score than placebo plus lifestyle therapy. (Funded by Novo Nordisk; NN8022-4180 ClinicalTrials.gov number, NCT02918279.).

OR33-01 Liraglutide for Weight Management in Pubertal Adolescents with Obesity: A Randomized Controlled Trial

Background: Pediatric obesity is a chronic disease with rising prevalence and limited treatment options; first-line intervention is lifestyle therapy, which is typically unsuccessful.¹ Liraglutide (3.0 mg) as an adjunct to lifestyle therapy has provided weight loss and improved cardiometabolic risk factors in adults.² Here we report the results of liraglutide 3.0 mg in adolescents with obesity who failed to respond to lifestyle therapy.

Methods: A multinational, randomized, double-blind trial (NCT02918279) with a 12-wk run-in of lifestyle therapy, 4-8-wk dose escalation, 52-wk maintenance period and 26-wk follow-up off trial drug. Adolescents aged 12-<18 years with obesity, stable weight and suboptimal response to lifestyle therapy alone were randomized 1:1 to once-daily subcutaneous liraglutide 3.0 mg (or maximum tolerated dose) or placebo (PBO), both as an adjunct to lifestyle therapy. Randomization was stratified by pubertal and glycemic (normal vs prediabetes/type 2 diabetes) status. Primary endpoint was change in BMI standard deviation score (SDS)³ from wk 0 to 56.

Results: Of 125 adolescents randomized to liraglutide 3.0 mg and 126 to PBO, 101 and 100 completed treatment at wk 56, respectively; 99 in each arm completed the trial at wk 82. 40.6% were male; mean age 14.5 years; mean BMI 35.6 kg/m²; mean BMI SDS 3.17. Liraglutide 3.0 mg was superior to PBO for change in BMI SDS at wk 56 (estimated treatment difference [ETD] -0.22; 95% CI -0.37, -0.08; p=0.0022). In the liraglutide 3.0 mg vs PBO arm, 43.25% vs 18.73% (p=0.0002) and 26.08% vs 8.11% (p=0.0006) of adolescents had ≥5% and ≥10% reduction in baseline BMI at wk 56, respectively. A significant difference in change in BMI was seen for liraglutide 3.0 mg vs PBO: ETD -4.64%; 95% CI -7.14, -2.14; p=0.0003. A significant reduction in waist circumference with liraglutide 3.0 mg was shown at wk 56 (p=0.0126). Greater weight regain/rebound in BMI SDS at wk 82 was seen for liraglutide 3.0 mg vs PBO after drug discontinuation (ETD 0.15; 95% CI 0.07, 0.23; p=0.0002). There were no significant differences in blood pressure, fasting lipids, fasting plasma glucose or HbA1c at wk 56. No unexpected safety concerns and no severe hypoglycemia were reported. During treatment (0–56 wks), more adolescents in the liraglutide 3.0 mg (64.8%) vs PBO arm (36.5%) reported gastrointestinal adverse events (AEs), and 3 vs 5 adolescents, respectively, reported serious AEs. Mental health questionnaire results were similar in both arms at wk 56. No effect on growth or pubertal development was found.

Conclusions: This trial demonstrates clinically meaningful⁴ weight loss in adolescents with obesity treated with liraglutide 3.0 mg as an adjunct to lifestyle therapy. The safety profile was similar to that observed in adults.

References

1. Ryder et al Obesity 2018;26:951

2. Pi-Sunyer et al N Engl J Med 2015;373:11

3. EMA doc. ref. EMEA/402888/2008

4. Grossman et al JAMA 2017;317:2417

Liraglutide in Children and Adolescents with Type 2 Diabetes

BACKGROUND

Metformin is the regulatory-approved treatment of choice for most youth with type 2 diabetes early in the disease. However, early loss of glycemic control has been observed with metformin monotherapy. Whether liraglutide added to metformin (with or without basal insulin treatment) is safe and effective in youth with type 2 diabetes is unknown.

METHODS

Patients who were 10 to less than 17 years of age were randomly assigned, in a 1:1 ratio, to receive subcutaneous liraglutide (up to 1.8 mg per day) or placebo for a 26-week double-blind period, followed by a 26-week open-label extension period. Inclusion criteria were a body-mass index greater than the 85th percentile and a glycated hemoglobin level between 7.0 and 11.0% if the patients were being treated with diet and exercise alone or between 6.5 and 11.0% if they were being treated with metformin (with or without insulin). All the patients received metformin during the trial. The primary end point was the change from baseline in the glycated hemoglobin level after 26 weeks. Secondary end points included the change in fasting plasma glucose level. Safety was assessed throughout the course of the trial.

RESULTS

Of 135 patients who underwent randomization, 134 received at least one dose of liraglutide (66 patients) or placebo (68 patients). Demographic characteristics were similar in the two groups (mean age, 14.6 years). At the 26-week analysis of the primary efficacy end point, the mean glycated hemoglobin level had decreased by 0.64 percentage points with liraglutide and increased by 0.42 percentage points with placebo, for an estimated treatment difference of -1.06 percentage points (P<0.001); the difference increased to -1.30 percentage points by 52 weeks. The fasting plasma glucose level had decreased at both time points in the liraglutide group but had increased in the placebo group. The number of patients who reported adverse events was similar in the two groups (56 [84.8%] with liraglutide and 55 [80.9%] with placebo), but the overall rates of adverse events and gastrointestinal adverse events were higher with liraglutide.

CONCLUSIONS

In children and adolescents with type 2 diabetes, liraglutide, at a dose of up to 1.8 mg per day (added to metformin, with or without basal insulin), was efficacious in improving glycemic control over 52 weeks. This efficacy came at the cost of an increased frequency of gastrointestinal adverse events. (Funded by Novo Nordisk; Ellipse ClinicalTrials.gov number, NCT01541215.).

Liraglutide effects in a paediatric (7-11 y) population with obesity: A randomized, double-blind, placebo-controlled, short-term trial to assess safety, tolerability, pharmacokinetics, and pharmacodynamics

BACKGROUND

Childhood obesity is a major public health concern with limited treatment options.

OBJECTIVE

The aim of this study was to assess safety, tolerability, pharmacokinetics, and pharmacodynamics during short-term treatment with liraglutide in children (7-11 y) with obesity.

METHODS

In this randomized, double-blind, placebo-controlled trial, 24 children received at least one dose of once-daily subcutaneous liraglutide (n = 16) or placebo (n = 8) starting at 0.3 mg with weekly dose escalations up to 3.0 mg or maximum tolerated dose, and 20 children completed the trial (14 in the liraglutide group and six in the placebo group). The primary endpoint was the number of adverse events.

RESULTS

Baseline characteristics (mean ± standard deviation) included the following: age 9.9 ± 1.1 years, weight 71.5 ± 15.4 kg, and 62.5% male. Thirty-seven adverse events were reported in nine liraglutide-treated participants (56.3%) versus 12 events in five placebo-treated participants (62.5%). Most adverse events were mild in severity, three were of moderate severity, and none were severe. Gastrointestinal disorders were the most frequently reported events occurring in 37.5% of liraglutide-treated participants compared with placebo (12.5%). Six asymptomatic hypoglycaemic episodes occurred in five participants of whom four were liraglutide treated. Liraglutide exposure was consistent with dose proportionality. Body weight was the only covariate to significantly impact exposure. A significant reduction in body mass index (BMI) Z score from baseline to end of treatment (estimated treatment difference: -0.28; P = 0.0062) was observed.

CONCLUSION

Short-term treatment with liraglutide in children with obesity revealed a safety and tolerability profile similar to trials in adults and adolescents with obesity, with no new safety issues.

Liraglutide in an Adolescent Population with Obesity: A Randomized, Double-Blind, Placebo-Controlled 5-Week Trial to Assess Safety, Tolerability, and Pharmacokinetics of Liraglutide in Adolescents Aged 12-17 Years

OBJECTIVES

To investigate the safety, tolerability, and pharmacokinetics of liraglutide in adolescents with obesity.

STUDY DESIGN

This was a randomized, double-blind, placebo-controlled trial. Twenty-one subjects, aged 12-17 years and Tanner stage 2-5, with obesity (body mass index [BMI] corresponding to both a BMI ≥95th percentile for age and sex and to a BMI of ≥30 kg/m² for adults; additionally, BMI was ≤45 kg/m²) were randomized (2:1) to receive 5 weeks of treatment with liraglutide (0.6 mg with weekly dose increase to a maximum of 3.0 mg for the last week) (n = 14) or placebo (n = 7). The primary endpoint was number of treatment-emergent adverse events (TEAEs). Secondary endpoints included safety measures, and pharmacokinetic and pharmacodynamic endpoints.

RESULTS

All participants receiving liraglutide, and 4 receiving placebo (57.1%), had at least 1 TEAE. The most common TEAEs were gastrointestinal disorders. No severe TEAEs, TEAE-related withdrawals, or deaths occurred. Twelve hypoglycemic episodes occurred in 8 participants receiving liraglutide and 2 in 1 participant receiving placebo. No severe hypoglycemic episodes were reported. Liraglutide exposure in terms of trough concentration increased with dose, although dose proportionality was confounded by unexpectedly low trough concentration values at the 2.4 mg dose. Exposure in terms of model-derived area under the plasma concentration time curve from 0 to 24 hours after dose in steady state was similar to that in adults with obesity.

CONCLUSIONS

Liraglutide had a similar safety and tolerability profile compared with adults when administered to adolescents with obesity, with no unexpected safety/tolerability issues. Results suggest that the dosing regimen approved for weight management in adults may be appropriate for use in adolescents.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01789086.

Liraglutide's safety, tolerability, pharmacokinetics, and pharmacodynamics in pediatric type 2 diabetes: a randomized, double-blind, placebo-controlled trial

BACKGROUND

The prevalence of type 2 diabetes (T2D) in youth is increasing. Treatment options beyond metformin and insulin are needed. The safety, tolerability, pharmacokinetics, and pharmacodynamics of liraglutide once daily in youth (10-17 years old) with T2D were investigated in a randomized, double-blind, placebo-controlled trial.

SUBJECTS AND METHODS

Youth treated with diet/exercise alone or with metformin and having a hemoglobin A1c (HbA1c) level of 6.5-11% were randomized to liraglutide (n=14) or placebo (n=7). Starting at 0.3 mg/day, doses were escalated weekly to 0.6, 0.9, 1.2, and 1.8 mg/day (or placebo equivalent) for 5 weeks.

RESULTS

Nineteen participants completed the trial. Baseline characteristics were similar between groups, with mean (SD) values for age of 14.8 (2.2) years, weight of 113.2 (35.6) kg (range, 57-214 kg), diabetes duration of 1.7 (1.4) years, and HbA1c level of 8.1% (1.2%). No serious adverse events (AEs), including severe hypoglycemia, occurred. Transient gastrointestinal AEs were most common at lower liraglutide doses during dose escalation. No significant changes in safety and tolerability parameters occurred. There was no evidence of pancreatitis or lipase elevations above three times the upper normal limit; calcitonin levels remained within the normal range. For liraglutide 1.8 mg, mean half-life was 12 h, and clearance was 1.7 L/h. After 5 weeks, the decline in HbA1c level was greater with liraglutide versus placebo (-0.86 vs. 0.04%, P=0.0007), whereas mean body weight remained stable (-0.50 vs. -0.54 kg, P=0.9703).

CONCLUSIONS

Liraglutide was well tolerated in youth with T2D, with safety, tolerability, and pharmacokinetic profiles similar to profiles in adults.

Weight maintenance and additional weight loss with liraglutide after low-calorie-diet-induced weight loss: the SCALE Maintenance randomized study

OBJECTIVE

Liraglutide, a once-daily human glucagon-like peptide-1 analog, induced clinically meaningful weight loss in a phase 2 study in obese individuals without diabetes. The present randomized phase 3 trial assessed the efficacy of liraglutide in maintaining weight loss achieved with a low-calorie diet (LCD).

METHODS

Obese/overweight participants (≥18 years, body mass index ≥30 kg m(-2) or ≥27 kg m(-2) with comorbidities) who lost ≥5% of initial weight during a LCD run-in were randomly assigned to liraglutide 3.0 mg per day or placebo (subcutaneous administration) for 56 weeks. Diet and exercise counseling were provided throughout the trial. Co-primary end points were percentage weight change from randomization, the proportion of participants that maintained the initial ≥5% weight loss, and the proportion that lost ≥5% of randomization weight (intention-to-treat analysis). ClinicalTrials.gov identifier: NCT00781937.

RESULTS

Participants (n=422) lost a mean 6.0% (s.d. 0.9) of screening weight during run-in. From randomization to week 56, weight decreased an additional mean 6.2% (s.d. 7.3) with liraglutide and 0.2% (s.d. 7.0) with placebo (estimated difference -6.1% (95% class intervals -7.5 to -4.6), P<0.0001). More participants receiving liraglutide (81.4%) maintained the ≥5% run-in weight loss, compared with those receiving placebo (48.9%) (estimated odds ratio 4.8 (3.0; 7.7), P<0.0001), and 50.5% versus 21.8% of participants lost ≥5% of randomization weight (estimated odds ratio 3.9 (2.4; 6.1), P<0.0001). Liraglutide produced small but statistically significant improvements in several cardiometabolic risk factors compared with placebo. Gastrointestinal (GI) disorders were reported more frequently with liraglutide than placebo, but most events were transient, and mild or moderate in severity.

CONCLUSION

Liraglutide, with diet and exercise, maintained weight loss achieved by caloric restriction and induced further weight loss over 56 weeks. Improvements in some cardiovascular disease-risk factors were also observed. Liraglutide, prescribed as 3.0 mg per day, holds promise for improving the maintenance of lost weight.

Patient-reported outcomes following treatment with the human GLP-1 analogue liraglutide or glimepiride in monotherapy: results from a randomized controlled trial in patients with type 2 diabetes

AIM

As weight gain and hypoglycaemia associated with glimepiride therapy can negatively impact weight perceptions, psychological well-being and overall quality of life in type 2 diabetes, we investigated whether liraglutide treatment could improve these factors.

METHODS

Seven hundred and thirty-two patients with type 2 diabetes completed a 77-item questionnaire during a randomized, 52-week, double-blind study with liraglutide 1.2 mg (n = 245) or 1.8 mg (n = 242) compared with glimepiride 8 mg (n = 245).

RESULTS

Mean (SE) decreases in glycated haemoglobin levels were greater with liraglutide 1.2 mg [-0.84 (0.08)%] and 1.8 mg [-1.14 (0.08)%] than glimepiride [-0.51 (0.08)%; p = 0.0014 and p < 0.0001, respectively]. Patients gained weight on glimepiride [mean (SE), 1.12 (0.27) kg] but lost weight on liraglutide [1.2 mg: -2.05 (0.28) kg; 1.8 mg: -2.45 (0.28) kg; both p < 0.0001]. Patient weight assessment was more favourable with liraglutide 1.8 mg [mean (SE) score: 40.0 (2.0)] than glimepiride [48.7 (2.0); p = 0.002], and liraglutide 1.8 mg patients were 52% less likely to feel overweight [odds ratio (OR) 0.48; 95% confidence interval (CI): 0.331-0.696]. Mean (SE) weight concerns were less with liraglutide [1.2 mg: 30.0 (1.2); 1.8 mg: 32.8 (1.2)] than glimepiride [38.8 (1.2); p < 0.0001 and p < 0.001, respectively], with liraglutide groups 45% less likely to report weight concern (OR 0.55, 95% CI: 0.41-0.73). Mean (SE) mental and emotional health and general perceived health improved more with liraglutide 1.8 mg [476.1 (2.8) and 444.2 (3.2), respectively] than glimepiride [466.3 (2.8) and 434.5 (3.2), respectively; p = 0.012 and p = 0.033, respectively].

CONCLUSIONS

Improved glycaemic control and decreased weight with liraglutide 1.8 mg vs. glimepiride can improve psychological and emotional well-being and health perceptions by reducing anxiety and worry associated with weight gain.

Efficacy and safety of the human glucagon-like peptide-1 analog liraglutide in combination with metformin and thiazolidinedione in patients with type 2 diabetes (LEAD-4 Met+TZD)

OBJECTIVE

To determine the efficacy and safety of liraglutide (a glucagon-like peptide-1 receptor agonist) when added to metformin and rosiglitazone in type 2 diabetes.

RESEARCH DESIGN AND METHODS

This 26-week, double-blind, placebo-controlled, parallel-group trial randomized 533 subjects (1:1:1) to once-daily liraglutide (1.2 or 1.8 mg) or liraglutide placebo in combination with metformin (1 g twice daily) and rosiglitazone (4 mg twice daily). Subjects had type 2 diabetes, A1C 7-11% (previous oral antidiabetes drug [OAD] monotherapy >or=3 months) or 7-10% (previous OAD combination therapy >or=3 months), and BMI <or=45 kg/m(2).

RESULTS

Mean A1C values decreased significantly more in the liraglutide groups versus placebo (mean +/- SE -1.5 +/- 0.1% for both 1.2 and 1.8 mg liraglutide and -0.5 +/- 0.1% for placebo). Fasting plasma glucose decreased by 40, 44, and 8 mg/dl for 1.2 and 1.8 mg and placebo, respectively, and 90-min postprandial glucose decreased by 47, 49, and 14 mg/dl, respectively (P < 0.001 for all liraglutide groups vs. placebo). Dose-dependent weight loss occurred with 1.2 and 1.8 mg liraglutide (1.0 +/- 0.3 and 2.0 +/- 0.3 kg, respectively) (P < 0.0001) compared with weight gain with placebo (0.6 +/- 0.3 kg). Systolic blood pressure decreased by 6.7, 5.6, and 1.1 mmHg with 1.2 and 1.8 mg liraglutide and placebo, respectively. Significant increases in C-peptide and homeostasis model assessment of beta-cell function and significant decreases in the proinsulin-to-insulin ratio occurred with liraglutide versus placebo. Minor hypoglycemia occurred more frequently with liraglutide, but there was no major hypoglycemia. Gastrointestinal adverse events were more common with liraglutide, but most occurred early and were transient.

CONCLUSIONS

Liraglutide combined with metformin and a thiazolidinedione is a well-tolerated combination therapy for type 2 diabetes, providing significant improvements in glycemic control.

Liraglutide versus glimepiride monotherapy for type 2 diabetes (LEAD-3 Mono): a randomised, 52-week, phase III, double-blind, parallel-treatment trial

BACKGROUND

New treatments for type 2 diabetes mellitus are needed to retain insulin-glucose coupling and lower the risk of weight gain and hypoglycaemia. We aimed to investigate the safety and efficacy of liraglutide as monotherapy for this disorder.

METHODS

In a double-blind, double-dummy, active-control, parallel-group study, 746 patients with early type 2 diabetes were randomly assigned to once daily liraglutide (1.2 mg [n=251] or 1.8 mg [n=247]) or glimepiride 8 mg (n=248) for 52 weeks. The primary outcome was change in proportion of glycosylated haemoglobin (HbA(1c)). Analysis was done by intention-to-treat. This trial is registered with ClinicalTrials.gov, number NTC00294723.

FINDINGS

At 52 weeks, HbA(1c) decreased by 0.51% (SD 1.20%) with glimepiride, compared with 0.84% (1.23%) with liraglutide 1.2 mg (difference -0.33%; 95% CI -0.53 to -0.13, p=0.0014) and 1.14% (1.24%) with liraglutide 1.8 mg (-0.62; -0.83 to -0.42, p<0.0001). Five patients in the liraglutide 1.2 mg, and one in 1.8 mg groups discontinued treatment because of vomiting, whereas none in the glimepiride group did so.

INTERPRETATION

Liraglutide is safe and effective as initial pharmacological therapy for type 2 diabetes mellitus and leads to greater reductions in HbA(1c), weight, hypoglycaemia, and blood pressure than does glimepiride.

Repaglinide versus nateglinide monotherapy: a randomized, multicenter study

OBJECTIVE

A randomized, parallel-group, open-label, multicenter 16-week clinical trial compared efficacy and safety of repaglinide monotherapy and nateglinide monotherapy in type 2 diabetic patients previously treated with diet and exercise.

RESEARCH DESIGN AND METHODS

Enrolled patients (n = 150) had received treatment with diet and exercise in the previous 3 months with HbA(1c) >7 and < or =12%. Patients were randomized to receive monotherapy with repaglinide (n = 76) (0.5 mg/meal, maximum dose 4 mg/meal) or nateglinide (n = 74) (60 mg/meal, maximum dose 120 mg/meal) for 16 weeks. Primary and secondary efficacy end points were changes in HbA(1c) and fasting plasma glucose (FPG) values from baseline, respectively. Postprandial glucose, insulin, and glucagon were assessed after a liquid test meal (baseline, week 16). Safety was assessed by incidence of adverse events or hypoglycemia.

RESULTS

Mean baseline HbA(1c) values were similar in both groups (8.9%). Final HbA(1c) values were lower for repaglinide monotherapy than nateglinide monotherapy (7.3 vs. 7.9%). Mean final reductions of HbA(1c) were significantly greater for repaglinide monotherapy than nateglinide monotherapy (-1.57 vs. -1.04%; P = 0.002). Mean changes in FPG also demonstrated significantly greater efficacy for repaglinide than nateglinide (-57 vs. -18 mg/dl; P < 0.001). HbA(1c) values <7% were achieved by 54% of repaglinide-treated patients versus 42% for nateglinide. Median final doses were 6.0 mg/day for repaglinide and 360 mg/day for nateglinide. There were 7% of subjects treated with repaglinide (five subjects with one episode each) who had minor hypoglycemic episodes (blood glucose <50 mg/dl) versus 0 patients for nateglinide. Mean weight gain at the end of the study was 1.8 kg in the repaglinide group as compared with 0.7 kg for the nateglinide group.

CONCLUSIONS

In patients previously treated with diet and exercise, repaglinide and nateglinide had similar postprandial glycemic effects, but repaglinide monotherapy was significantly more effective than nateglinide monotherapy in reducing HbA(1c) and FPG values after 16 weeks of therapy.

Combination therapy for type 2 diabetes: repaglinide plus rosiglitazone

AIMS

This 24-week, randomized, multicentre, open-label, parallel-group clinical trial compared efficacy and safety of repaglinide monotherapy, rosiglitazone monotherapy, and combination therapy (repaglinide plus rosiglitazone) in Type 2 diabetes after unsatisfactory response to sulphonylurea or metformin monotherapy.

METHODS

Enrolled patients (n = 252) were adults having Type 2 diabetes for at least 1 year, with HbA(1c) values > 7.0% after previous monotherapy (sulphonylurea or metformin, >/= 50% maximal dose). Prior therapy was withdrawn for 2 weeks, followed by randomization to repaglinide, rosiglitazone, or repaglinide/rosiglitazone. Study treatments were initiated with a 12-week dose optimization period (doses optimized according to labelling), followed by a 12-week maintenance period. Efficacy endpoints were changes in HbA(1c) values (primary) or fasting plasma glucose values (secondary).

RESULTS

Baseline HbA(1c) values were comparable (9.3% for repaglinide, 9.0% for rosiglitazone, 9.1% for combination). Mean changes in HbA(1c) values at the end of treatment were greater for repaglinide/rosiglitazone therapy (-1.43%) than for repaglinide (-0.17%) or rosiglitazone (-0.56%) monotherapy. Reductions of fasting plasma glucose values were also greater for combination therapy (-5.2 mmol/l, -94 mg/dl) than for repaglinide monotherapy (-3.0 mmol/l, -54 mg/dl) or rosiglitazone monotherapy (-3.7 mmol/l, -67 mg/dl). Minor hypoglycaemic events occurred in 9% of combination therapy patients, vs. 6% for repaglinide and 2% for rosiglitazone. Individual weight gains for combination therapy were correlated to HbA(1c) response.

CONCLUSIONS

The combination therapy regimen was well tolerated. In patients previously showing unsatisfactory response to oral monotherapy, glycaemic reductions were greater for the repaglinide/rosiglitazone combination regimen than for use of either repaglinide or rosiglitazone alone.

Treatment of type 2 diabetes with a combination regimen of repaglinide plus pioglitazone

The efficacy and safety of combination therapy (repaglinide plus pioglitazone) was compared to repaglinide or pioglitazone in 24-week treatment of type 2 diabetes. This randomized, multicenter, open-label, parallel-group study enrolled 246 adults (age 24-85) who had shown inadequate response in previous sulfonylurea or metformin monotherapy (HbA(1c) > 7%). Prior therapy was withdrawn for 2 weeks, followed by randomization to repaglinide, pioglitazone, or repaglinide/pioglitazone. In the first 12 weeks of treatment, repaglinide doses were optimized, followed by 12 weeks of maintenance therapy. Pioglitazone dosage was fixed at 30 mg per day. Baseline HbA(1c) values were comparable (9.0% for repaglinide, 9.1% for pioglitazone, 9.3% for combination). Mean changes in HbA(1c) values at the end of treatment were -1.76% for repaglinide/pioglitazone, -0.18% for repaglinide, +0.32% for pioglitazone. Fasting plasma glucose reductions were -82 mg/dl for combination therapy, -34 mg/dl for repaglinide, -18 mg/dl for pioglitazone. Minor hypoglycemia occurred in 5% of patients for the combination, 8% for repaglinide, and 3% for pioglitazone. Weight gains for combination therapy were correlated to individual HbA(1c) reductions. In summary, for patients who had previously failed oral antidiabetic monotherapy, the combination repaglinide/pioglitazone had acceptable safety, with greater reductions of glycemic parameters than therapy using either agent alone.

Efficacy and safety of combination therapy: repaglinide plus metformin versus nateglinide plus metformin

OBJECTIVE

An open-label, parallel-group, randomized, multicenter trial was conducted to compare efficacy and safety of repaglinide versus nateglinide, when used in a combination regimen with metformin for treatment of type 2 diabetes.

RESEARCH DESIGN AND METHODS

Enrolled patients (n = 192) had HbA(1c) >7% and < or =12% during previous treatment with a sulfonylurea, metformin, or low-dose Glucovance (glyburide < or =2.5 mg, metformin < or =500 mg). After a 4-week metformin run-in therapy period (doses escalated to 1,000 mg b.i.d.), patients were randomized to addition of repaglinide (n = 96) (1 mg/meal, maximum 4 mg/meal) or nateglinide (n = 96) (120 mg/meal, reduced to 60 mg if needed) to the regimen for 16 weeks. Glucose, insulin, and glucagon were assessed after a liquid test meal at baseline and week 16.

RESULTS

Final HbA(1c) values were lower for repaglinide/metformin treatment than for nateglinide/metformin (7.1 vs. 7.5%). Repaglinide/metformin therapy showed significantly greater mean reductions of HbA(1c) (-1.28 vs. -0.67%; P < 0.001) and of fasting plasma glucose (FPG) (-39 vs. -21 mg/dl; P = 0.002). Self-monitoring of blood glucose profiles were significantly lower for repaglinide/metformin before breakfast, before lunch, and at 2:00 A.M. Changes in the area under the curve of postprandial glucose, insulin, or glucagon peaks after a test meal were not significantly different for the two treatment groups during this study. Median final doses were 5.0 mg/day for repaglinide and 360 mg/day for nateglinide. Safety assessments were comparable for the two regimens.

CONCLUSIONS

The addition of repaglinide to metformin therapy resulted in reductions of HbA(1c) and FPG values that were significantly greater than the reductions observed for addition of nateglinide.

Assessment of growth and immunologic function in HIV-infected and exposed children

Many children who are HIV infected grow poorly. An epidemiological framework guided a retrospective chart review assessing growth in three groups of children (n = 192): (a) children who were HIV infected secondary to maternal transmission (n = 77), (b) children who had been HIV-positive at birth but became seronegative and continue to be observed (seroreverters) (n = 84), and (c) HIV-infected children who had died (n = 31). Growth failure in the HIV-infected children was significantly greater than that expected in the general population. The seroreverters also demonstrated significantly more growth failure than that expected in the general population. Of the children who had linear growth failure, only 3 of 12 HIV-infected children and 2 of 11 seroreverters also had inadequate weight gain. However, 13 of 15 children with growth failure who subsequently died had poor weight gain. HIV classification was not significantly related to growth. These findings extend our understanding to a large, urban population of children in the United States including those who are older than children in other studies and who developed HIV through perinatal transmission. Nursing clinical practice and research implications are offered.

Assessment of growth by primary health care providers

INTRODUCTION

Precise measurements of children are critical for accurate growth assessment. Many children are referred to endocrine practices in error because heights are obtained but plotted on length growth charts, giving the appearance that growth has decelerated.

METHOD

In an attempt to evaluate growth assessment in primary care practices (PCPs), we instituted a telephone survey to gather the following data: (a) how often children are measured, (b) the criteria for whether children are measured standing or lying, (c) the methods for measuring children, and (d) whether measurements are plotted on growth charts and by whom.

RESULTS

In PCPs, children were reported to be measured at every visit or only at well child visits. The criteria most frequently used to determine when children should be measured standing was "if they can stand, they are measured standing." Significantly more pediatric practices than family practices measured children standing at the correct age. Heights were most often obtained on a scale with a floppy arm. All but 4 practices reported that measurements on growth charts were plotted by the nurse or physician.

DISCUSSION

Many practices had an incorrect policy related to obtaining measurements of length versus height. Children are measured with the correct equipment in only 22% of PCPs for height and 12% of PCPs for length. Most PCPs are diligent about plotting growth data. Clearly, education of personnel in PCPs is crucial so that accurate growth measurements can be obtained, necessary referrals can be made, and unnecessary referrals can be avoided.

Risk factors for cardiovascular disease in children with Type I diabetes

BACKGROUND

The major cause of morbidity and mortality in individuals with Type I insulin-dependent diabetes mellitus (IDDM) is premature and extensive atherosclerotic cardiovascular disease (CVD).

OBJECTIVES

To determine the prevalence and predictors of hypercholesterolemia and to examine the distribution and interrelationship of risk factors for CVD.

METHODS

This observational (mixed-longitudinal) study, guided by an epidemiologic framework, assessed a sample of 140 children with IDDM. Total cholesterol (TC) and diabetes control were measured in the total sample. Standard CVD risk factors were measured in a subsample of 67 children.

RESULTS

Observed frequency of TC greater than the 75th percentile and greater than the 95th percentile was significantly more than expected (p < 0.01 and p < 0.0001, respectively). In the total sample, TC-CVD risk factor associations were not observed. However, diabetes control and physical activity were correlated with TC in the risk sample of children at highest risk, as demonstrated by hypercholesterolemia.

CONCLUSIONS

Results demonstrate the importance of assessing the lipid profile in children with IDDM and monitoring CVD risk factors in hyperlipidemic children with IDDM. Future research should focus on prospective longitudinal studies in population-based multiethnic samples of children with IDDM.

Factors predicting cerebral edema in young children with diabetic ketoacidosis and new onset type I diabetes

We have attempted to identify any characteristics which could be used to predict the development of cerebral edema in four children under 5 years of age with new onset insulin-dependent diabetes mellitus and diabetic ketoacidosis. We retrospectively analysed and compared the concentration of serum sodium (corrected for serum glucose value) and effective serum osmolality of these 4 children with values of 10 age-matched controls with new onset insulin-dependent diabetes mellitus who did not develop cerebral edema during treatment of diabetic ketoacidosis. The initial serum sodium values of the two groups were not statistically different. Patients who developed cerebral edema had lower initial serum glucose values and effective serum osmolality. During treatment, patients who developed cerebral edema had consistently lower mean serum sodium and osmolality than controls at each 4-h interval after the first 4 h of therapy. Serum sodium and osmolality declined progressively after the initiation of therapy in cerebral edema patients, while remaining stable in controls. These data suggest that children who develop cerebral edema during treatment for diabetic ketoacidosis initially may have a relatively normal serum osmolality and subsequently develop progressive hyponatremia and/or a trend of declining serum sodium before developing cerebral edema.

Improvement of cortical morphology in infantile hydrocephalic animals after ventriculoperitoneal shunt placement

As a sequel to our previous descriptions of the pathological changes induced by hydrocephalus in the infantile cerebral cortex, the study presented here has evaluated the effects of surgical decompression on cortical cytology and cytoarchitecture. Hydrocephalus was induced in 14 kittens by the intracisternal injection of kaolin at 4 to 11 days of age. Nine of these hydrocephalic animals received low-pressure ventriculoperitoneal shunts at 9 to 15 days after kaolin injection; these animals were monitored preoperatively and postoperatively by ultrasound and were killed at various postshunt intervals up to 30 days. Five normal or saline-injected animals served as age-matched controls. At the time of shunt placement, the ventricular index confirmed that all recipient animals had attained moderate or severe degrees of ventriculomegaly. Within 3 days after shunt placement, the size of the lateral ventricles had decreased to control levels and was accompanied by rapid and dramatic improvements in behavior and skull ossification. When the animals were killed, gross inspection revealed that about half of the animals exhibited mild to moderate ventriculomegaly, with cortical mantles 50 to 80% their normal thickness. Tissue from frontal (primary motor), parietal (association), and occipital (primary visual) cortical areas was processed for light microscopic analysis. Pyknotic or dark shrunken neurons, which are found typically in hydrocephalic brains, were observed only occasionally in the cortex of shunted animals. Gliosis and mild edema were prevalent, however, in the periventricular white matter. The laminae of the cerebral cortex could be identified in all shunted animals. In those animals with mild residual ventriculomegaly, the entire cortical mantle was somewhat compressed, as evidenced by an increased packing density of neurons. Furthermore, the somata of some neurons were disoriented. Overall, these results indicate that most of the morphological characteristics of the cerebral cortex are preserved after surgical decompression and suggest that ventriculoperitoneal shunts may prevent neuronal damage and/or promote neuronal repair.

Testosterone infusion reduces nocturnal luteinizing hormone pulse frequency in pubertal boys

Administration of testosterone (T) can inhibit LH secretion in early pubertal boys. However, the GnRH pulse generator is relatively resistant to the effects of T, since T infusion beginning at 2100 h, 3 h before the usual nighttime increase in T, does not suppress the characteristic increase in LH pulse frequency or amplitude associated with the onset of sleep in early pubertal boys. To test the hypothesis that the hypothalamic-pituitary axis must be exposed to T for a longer duration to suppress the nocturnal rise in LH pulse frequency and amplitude, we infused saline or T at one third the adult male production rate (320 nmol/h), beginning at 1200 h on two consecutive weekends in each of eight early to midpubertal boys. Blood was obtained from 2000-0800 h every 10 min for LH and every 30 min for T measurements. T infusion increased the mean plasma T concentration from 6.9 +/- 1.7 to 11.8 +/- 1.4 nmol/L (P less than 0.01) between 2000-0800 h. Despite the T infusion, the nocturnal rise in mean LH concentration and LH pulse frequency persisted, suggesting that the nocturnal amplification of LH, and by inference GnRH, secretion is resistant to the negative feedback effects of T. A higher dose of T, approximating the adult male production rate (960 nmol/h), was given to eight additional boys beginning at 1200 h. The mean T concentration increased from 4.2 +/- 1.7 to 20.8 +/- 3.1 (P less than 0.001) nmol/L between 2000-0800 h. The mean plasma LH concentration was suppressed by T infusion from 5.2 +/- 0.5 to 2.9 +/- 0.4 IU/L, and LH pulse frequency decreased from 0.50 +/- 0.04 to 0.27 +/- 0.11 pulses/boy/h (P less than 0.01). There was no nocturnal amplification of LH secretion, but high amplitude LH pulses did occur during the night in six of the eight boys. The low dose T infusion had no effect on pituitary LH release by exogenous GnRH. With the high dose T infusion, however, the ability of GnRH, at 25 ng/kg but not at 250 ng/kg, to release pituitary LH was amplified. Thus, T supplementation at one third the adult male production rate does not blunt the sleep-associated nighttime rise in LH pulse frequency or LH concentration. T infusion approximating the adult male production rate suppresses the nocturnal increase in LH pulse frequency and mean LH concentration, and high amplitude, slow frequency LH pulses similar to patterns seen in adult men persist.(ABSTRACT TRUNCATED AT 400 WORDS)

Tactical considerations for HIS strategy--Part II

In the second part of his two-part commentary, Paul M. Hale describes the four primary HIS strategies emerging in response to the trends described in Part I.

Nocturnal serum growth hormone concentration is not augmented by short-term testosterone infusion in pubertal boys

Chronic exposure to testosterone (T) increases growth hormone (GH) secretion. To determine whether acute exposure to T would also enhance GH secretion, we infused saline, followed 1 wk later by T, for 18-24 h at one-third the adult male production rate in 12 pubertal boys and at the adult male production rate in eight additional pubertal boys. Blood was obtained every 20 min for GH and every 30 min for T from 2000-0800 h. Though infusion significantly increased serum T concentrations in all 20 boys, mean GH concentration, GH pulse frequency, and GH pulse amplitude did not increase compared to the saline infusion night. The secretory dynamics of GH as a function of 3-h time blocks from 2000-0800 h were also determined in the eight boys who received the higher dose of T. The profile for mean GH concentration, pulse frequency, pulse amplitude, and peak area were not affected by acute infusion of T at concentrations sufficient to alter LH secretion. This suggests that, at least in pubertal boys, one must be exposed to T for a period longer than 12-18 h to induce increased GH secretion.

T cell multideterminant regions in the human immunodeficiency virus envelope: toward overcoming the problem of major histocompatibility complex restriction

Helper T cell determinants should be an important component of an anti-human immunodeficiency virus (HIV) vaccine aimed at either antibody or cytotoxic T cell immunity. However, model protein studies have raised concern about the usefulness of any single determinant, because a given determinant is likely to be seen by only a small subset of major histocompatibility complex (MHC) types within the population. Here, we use 44 peptides, including ones predicted and not predicted on the basis of amphipathicity to be potential T cell sites, to locate T cell antigenic determinants recognized by mice of four MHC haplotypes immunized with the whole gp 160 envelope protein. Although the preselection of peptides necessitates caution in a statistical analysis, alpha-amphipathic peptides predominated among sites eliciting the strongest response. Although we have not tested the entire sequence, we have identified six multideterminant regions, in which overlapping peptides are recognized by mice of either three or all four MHC types. Four of the six regions have sequences relatively conserved among HIV-1 isolates. The existence of such multideterminant regions recognized by multiple MHC haplotypes suggests the possibility that use of peptides longer than a minimal determinant and containing several overlapping determinants may be a possible approach to circumvent the serious problem of MHC restriction in peptide vaccines aimed at eliciting T cell immunity.

Effects of human growth hormone on insulin-stimulated glucose metabolism in 3T3-F442A adipocytes

GH is believed to play a role in promoting insulin resistance in patients with diabetes and with GH excess. The means by which GH produces insulin resistance may be through direct suppression of glucose metabolism in target cells (insulin-independent) or by interfering with the ability of insulin to stimulate glucose metabolism (insulin-dependent). In 3T3-F442A adipocytes, long term incubation (24-72 h) with GH directly inhibits glucose oxidation and lipid synthesis in the absence of insulin. To distinguish the insulin-independent effects of GH on glucose metabolism from the insulin-dependent effects of GH, we examined the effect of GH on insulin-stimulated lipid accumulation in cultured 3T3-F442A adipocytes. Cells were incubated for 48-72 h with GH and then treated with insulin. Insulin stimulated lipid accumulation in GH-pretreated and control cells. Compared to control, GH-treated cells had lower absolute levels of lipid accumulation in the absence of insulin and at each insulin concentration tested. Thus, GH directly suppresses basal lipid accumulation and lowers the response to insulin. In addition, a 10 times higher insulin concentration was required to reach maximum stimulation of lipid accumulation in GH-treated cells (50 ng/ml) than in control cells (5 ng/ml). When cells were exposed simultaneously to insulin and GH for 72 h, GH treatment inhibited the ability of insulin to stimulate lipid accumulation, and the degree of suppression by GH was related to the GH concentration present. These observations suggest that GH suppresses glucose metabolism not only in the absence but also in the presence of insulin. Since short term (4-h) incubation with GH increases glucose metabolism transiently in GH-deficient preparations, we also examined the influence of short term incubation with GH on insulin responses. Cells were incubated for 4 h with varying concentrations of insulin in the simultaneous presence or absence of GH. Insulin stimulated the conversion of glucose to lipid when tested alone or in the presence of GH. Short term exposure to GH alone also stimulated glucose metabolism. The stimulation of lipid accumulation at insulin concentrations less than 5 ng/ml was greater with GH, but responses were comparable above 5 ng/ml insulin. The ability of insulin to bind to its receptor was not affected by prior treatment with GH for either short or prolonged time periods.(ABSTRACT TRUNCATED AT 400 WORDS)

Increased luteinizing hormone pulse frequency during sleep in early to midpubertal boys: effects of testosterone infusion

Gonadotropin secretion is pulsatile in prepubertal and early pubertal boys, and the onset of puberty is characterized by a sleep-associated rise in LH pulse amplitude. To determine whether an augmentation in LH pulse frequency as well as amplitude occurs at the onset of puberty, we studied gonadotropin secretion in 21 early to midpubertal boys. Blood samples were taken every 20 min (every 15 min in 4 boys) for LH determinations. A 2-fold increase in LH pulse frequency occurred during the nighttime sampling period (2200-0400 h) compared to that in the hours when the boys were awake (1000-2200 h). The maximum frequency (0.7 pulses/h) occurred between 2400 and 0200 h. The mean plasma LH concentration increased during the night from 2.3 +/- 0.2 (+/- SE) mIU/mL (2.3 +/- 0.2 IU/L) between 2000-2200 h to a maximum of 6.2 +/- 0.4 (6.2 +/- 0.4 IU/L) between 0200-0400 h. The mean plasma LH decreased to 5.5 +/- 0.4 mIU/mL (5.5 +/- 0.4 IU/L) between 0400-0600 h and to 4.2 +/- 0.5 (4.2 +/- 0.5 IU/L) between 0600-0800 h. Plasma testosterone rose during the night to a mean maximum value of 2.4 +/- 0.5 (+/- SE) ng/mL (8.3 +/- 1.7 nmol/L). This finding suggested that the rise in testosterone might play a role in decreasing LH secretion during the later hours of sleep (after 0400 h). To address this question and to study further the effects of testosterone in early puberty, we measured plasma LH concentrations every 10 min from 2000-0800 h in 8 early to mid-pubertal boys before and during short term testosterone administration. Saline or testosterone at a concentration of 9.33 micrograms/mL (32 mumol/L) was infused at a rate of 10 mL/h from 2100-1200 h to shift the nighttime testosterone rise 3 h earlier than would occur spontaneously. Blood samples were obtained every 10 min for LH and every 30 min for testosterone determinations from 2000-0800 h. Pituitary responsiveness was assessed by administering sequential doses of synthetic GnRH (25 and 250 ng/kg) at 1000 and 1200 h, respectively. The nighttime increase in LH pulse frequency and mean plasma LH concentration occurred between 2300 and 0200 h despite testosterone infusion. However, testosterone infusion was associated with significantly lower mean plasma LH concentrations from 0200-0800 h compared to those on the night of the saline infusion. Pituitary responsiveness to synthetic GnRH was unaltered by testosterone administration.(ABSTRACT TRUNCATED AT 400 WORDS)

State of the art: islet cell antibody tests

The discovery of anti-islet cell antibodies (ICAb's) in the sera of individuals with insulin- dependent diabetes (IDDM) was a significant milestone in the history of diabetes research. ICAb's have been found in the sera of 60%-85% of new-onset diabetic patients. It has been suggested that ICAb's play a role in the destruction of beta cells possibly by complement- mediated beta cell lysis, or by acting as mediators in antibody- dependent cell-mediated cytotoxicity. ICAb's have been shown to be markers of ongoing beta cell destruction. The presence of ICAb's has preceded the appearance of clinical evidence of IDDM by as long as eight years. The detection of ICAb's in first-degree relatives of individuals with IDDM identifies a population at risk for developing IDDM. Means of intervention need to be established to prevent progressive beta cell destruction in these individuals.