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L Van Gaal

Publications and source records attributed to L Van Gaal.

At least 19 recordsLinked to original sources
PubMed2007

Reference values for sleep-related respiratory variables in asymptomatic European children and adolescents.

AIM: Only a limited number of studies, designed to establish normal values for sleep-related respiratory variables in children, have been reported, and all are non-European. The aim of this study was to expand the knowledge on normative data in children. METHODS: Subjects ranging from 6 to 16 years were recruited and underwent full polysomnography. Only subjects without sleep disordered breathing or other sleep problems as assessed by clinical history were included. RESULTS: Sixty subjects were studied ( = 11.7 +/- 2.6 years; 28 boys; = 118.8 +/- 30.6%). was 0.85 +/- 1.06 (range: 0.0-5.5). was 0.06 +/- 0.16 (range: 0.0-0.9); 11 patients had a total of 31 obstructive apneas. Only five obstructive hypopneas were detected with = 0.08 +/- 0.17 (range: 0.0-0.9). was 1.98 +/- 1.39 (range: 0.1-7.2). was 97.0 +/- 0.6% (range: 96.0-98.0); was 91.8 +/- 2.7% (range: 82.0-96.0); <% of total sleep time with SaO2 >or= 95%> was 98.7 +/- 2.1% (range: 90.8-100.0); was 0.8 +/- 0.9 (range: 0.0-4.9) and was 6.1 +/- 1.8 (range: 2.7-10.9). Snoring was detected in 15 patients (4 overweight subjects), with no difference in patient characteristics and sleep-related respiratory variables between snorers and non-snorers. Subjects in the overweight group (n = 22) had a lower SaO2nadir (90.8 +/- 2.7 vs. 92.4 +/- 2.6; P = 0.01) and a higher ODI (1.3 +/- 1.3 vs. 0.4 +/- 0.4; P = 0.0002) than their normal weight peers. CONCLUSION: Our data are in agreement with other non-European studies, designed to establish normal values in children.

Adolescent↗
PubMed2006

Sex- and season-dependent differences in C-peptide levels at diagnosis of immune-mediated type 1 diabetes.

AIMS/HYPOTHESIS: The incidence of type 1 diabetes varies according to age, sex and season of diagnosis. We investigated whether these and other clinical, biological and anthropometric parameters were correlated with residual beta cell function in newly diagnosed patients, since it is possible that the nature of external and/or genetic disease accelerators may be (partly) reflected in the inaugural disease presentation. MATERIALS AND METHODS: The correlates of random C-peptide levels sampled shortly after diagnosis (median [interquartile range]: 3 [0-14] days) were studied by multivariate analysis in 1,883 islet-antibody-positive diabetic patients aged <40 years who were diagnosed between 1989 and 2000. RESULTS: Higher C-peptide levels (above percentile 50 of patients) were associated with older age at diagnosis, female sex, diagnosis in the high-incidence season (October to March), less-decreased BMI (expressed as a standard deviation score), lower insulin requirements after stabilisation, lower prevalence of ketonuria and a less-increased glycaemia at diagnosis (all p < 0.001). C-peptide levels were not correlated with calendar year at diagnosis, duration of symptoms prior to diagnosis, HLA-DQ2/DQ8 genotype or islet antibody status. CONCLUSIONS/INTERPRETATION: Sex- and season-dependent differences in residual functional beta cell mass and/or insulin resistance have been identified at diagnosis of type 1 diabetes. They may reflect differences in disease-precipitating external or lifestyle factors and should be further investigated longitudinally in prediabetes to further identify putative aetiological factors, which may provide targets for prevention.

Adolescent↗
PubMed2006

Screening for melanocortin-4 receptor mutations in a cohort of Belgian morbidly obese adults and children.

OBJECTIVE: To investigate whether pathogenic melanocortin-4 receptor (MC4R) mutations are a common cause of obesity in Belgium. DESIGN: Cross-sectional mutation analysis. SUBJECTS: In total, 95 morbidly obese adults (mean age 44.02+/-11.35 years; mean BMI 47.87+/-4.17 kg/m2 and 123 obese children and adolescents were screened for mutations in MC4R (mean age 16.56+/-2.58 years; BMI>95th percentile for age and sex; mean % overweight 170.86 +/- 23.63). MEASUREMENTS: A series of anthropometric (e.g. weight, height, waist, hip), biochemical and clinical measurements were performed on all subjects. The entire coding region of MC4R was screened using DHPLC, a highly sensitive and specific method for mutation analysis. Direct sequencing was performed when the chromatogram deviated from the WT pattern. RESULTS: Mutation screening of a cohort of Belgian obese adults and children did not detect any pathogenic mutations as only the previously described polymorphisms Val103Ile, Thr112Met and Ile251Leu were detected. CONCLUSION: Pathogenic mutations in MC4R are not a common cause of obesity in a Belgian population of obese adults, children and adolescents.

Adolescent↗
PubMed2005

Effects of micronized fenofibrate and vitamin E on in vitro oxidation of lipoproteins in patients with type 1 diabetes mellitus.

OBJECTIVE: The primary objective was to compare the antioxidant activity of micronised fenofibrate 200 mg to 400 IU of vitamin E and placebo, on the LDL and VLDL particles of patients with type 1 diabetes. The secondary objective was to investigate the possible synergy between micronized fenofibrate and vitamin E and to compare the efficacy of these treatments on lipids. METHODS: A double-blind, placebo-controlled trial in which patients were randomised into three treatment groups after a wash-out period of 8 weeks: the placebo group (Pla/Pla-group) in which patients received placebo during two consecutive periods of 8 weeks, the vitamin E group (Vit E/Vit E-group) in which patients received Vitamin E during two consecutive periods, and the fenofibrate/Vitamin E group (Fen/Fen + Vit E-group) in which patients received fenofibrate during the first period, followed by fenofibrate and vitamin E during the consecutive period. Blood samples taken at each visit, were analysed for routine biochemistry, blood lipids and copper mediated lipid peroxidation in vitro. RESULTS: The lag time of the non-HDL lipoprotein oxidation increased in the group given fenofibrate. The lag-time increased further when fenofibrate and vitamin E were given in association. (This reached significance in the intention-to-treat population, P = 0.034). The AUC of TBARS formation in the Vit E/Vit E group decreased after the first period, but this effect was not enhanced by continuing vitamin E for another 8 weeks. The AUC of TBARS formation did not change significantly after the administration of fenofibrate. Only after the second period, when vit E was given in association, the AUC of TBARS formation decreased significantly (P = 0.004). Fenofibrate caused a significant decrease in total and LDL-cholesterol and triglycerides (P < 0.05). In contrast, vitamin E had no effect on lipids. CONCLUSIONS: The combination of micronized fenofibrate 200 mg/day and vitamin E 400 IU/day tended to increase the resistance of non-HDL lipoproteins to copper-mediated oxidation, shown by a prolongation of the lag-time. Vitamin E administration only, decreased the oxidation of non-HDL lipoproteins shown by a reduction of TBARS formation. This protective effect of vitamin E tended to be amplified by micronized fenofibrate.

Adult↗
PubMed2005

X-PERT: weight reduction with orlistat in obese subjects receiving a mildly or moderately reduced-energy diet: early response to treatment predicts weight maintenance.

AIM: To determine the effect of two different levels of energy deficit on weight loss in obese patients treated with orlistat. METHODS: Patients (n=430) were randomized in a 1-year, multicentre, open-label, parallel group study conducted at 23 hospital centres and university medical departments worldwide. Obese outpatients (body mass index 30--43 kg/m(2)) aged 18--70 years with a body weight of >or=90 kg and a waist circumference of >or=88 cm (women) or >or=102 cm (men) were treated with orlistat 120 mg three times daily plus a diet that provided an energy deficit of either 500 or 1,000 kcal/day for 1 year. Orlistat treatment was discontinued in patients who did not achieve >or=5% weight loss after assessment at 3 and 6 months. The primary outcome measure was change in body weight from baseline at week 52. RESULTS: Reported mean difference in energy intake between the two groups (500-1,000 kcal/day deficit) at weeks 24 and 52 was actually 111 and 95 kcal/day respectively. Of the 430 patients involved in the study, 295 achieved >or=5% weight loss at both 3 and 6 months. In this population, at week 52, weight loss from baseline was similar for patients randomized to either the 500 or the 1,000 kcal/day deficit diet (-11.4 kg vs. -11.8 kg, respectively; p=0.778). After 12 months of treatment with orlistat, 84% (n=118/141) and 85% (n=131/154) of patients in the 500 and 1,000 kcal/day deficit groups, respectively, achieved >or=5% weight loss, and 50% (n=70/141) and 53% (n=82/154) of patients, respectively, achieved >or=10% weight loss. Patients in both the diet treatment groups showed similar significant improvements in blood pressure, lipid levels and waist circumference at week 52. CONCLUSIONS: Treatment with orlistat was associated with a clinically beneficial weight loss, irrespective of the prescribed dietary energy restriction (-500 or -1000 kcal/day). Patients who achieved >or=5% weight loss at 3 months achieved long-term, clinically beneficial weight loss with orlistat plus either diet. Therefore, identifying patients who lose at least 5% weight after 3 months and who maintain this weight loss up to 6 months is a valuable treatment algorithm to select patients who will benefit most from orlistat treatment in combination with diet.

Adolescent↗
PubMed2004

A randomized double-blind placebo-controlled study of the long-term efficacy and safety of topiramate in the treatment of obese subjects.

BACKGROUND: Treatment of obese subjects with topiramate has recently been associated with significant weight loss in a 6-month dose-ranging study. OBJECTIVE: To investigate the long-term efficacy and safety of topiramate in obese subjects. DESIGN: Randomised, double-blind, placebo-controlled study investigating three doses of topiramate: 96, 192, and 256 mg/day. All subjects also participated in a nonpharmacological weight-loss programme. SUBJECTS: The study included 1289 subjects 18-75 y with a body mass index >/=30 kg/m(2) and <50 kg/m(2) in the absence of comorbidities, or >/=27 kg/m(2) and <50 kg/m(2) in the presence of controlled hypertension and/or dyslipidaemia. DURATION: The original study design was for a 6-week, single-blind, placebo run-in phase followed by an 8-week titration phase and 2 y of maintenance at the assigned dose. Sponsor ended study early in order to develop a new controlled-release formulation with the potential to enhance tolerability and simplify dosing in this patient population. Therefore, none of the subjects completed the full 2 y of treatment. Efficacy results are based on subjects who were enrolled early enough to have had an opportunity to complete 1 y at their assigned dose (modified intent-to-treat population, MITT) before learning of the decision to terminate the study. Safety results are based on all subjects who took at least one dose of study medication. RESULTS: The safety population consisted of 1282 subjects, and the MITT efficacy population was 854 subjects. At 60 weeks, subjects in the placebo group lost 1.7% of their baseline body weight, while subjects in the topiramate 96, 192, and 256 mg/day treatment groups lost 7.0, 9.1, and 9.7%, respectively (P<0.001, MITT, last observation carried forward). Weight loss >/=5% of baseline weight was achieved by 18% of subjects in the placebo arm vs 54, 61, and 67% of subjects receiving topiramate 96, 192, and 256 mg/day, respectively; weight loss >/=10% was achieved by 6 vs 29, 40, and 44%, respectively (P<0.001). Weight loss was accompanied by significant improvements in blood pressure (systolic/diastolic changes of +0.4/+1.0, -3.1/-1.3, -5.7/-3.4, and -4.6/-2.4 mmHg were observed for placebo, topiramate 96 mg/day, 192 mg/day, and 256 mg/day, respectively, P<0.001) and glucose and insulin. The most common adverse events more frequently observed in topiramate-treated subjects occurred mostly during the titration phase and were related to the central or peripheral nervous system and included paresthesia, difficulty with concentration/attention, depression, difficulty with memory, language problems, nervousness, and psychomotor slowing. CONCLUSION: Topiramate treatment of obese subjects over the course of 1 y resulted in clinically significant weight loss. Improvements were also observed in blood pressure and glucose tolerance.

Adult↗
PubMed2004

Primary prevention of coronary heart disease in general practice: a cross sectional population study.

The aim of this study was to assess the interventions by general practitioners on cardiovascular risk factors among persons without a history of cardiovascular disease attending for a cardiovascular check-up. All inhabitants of three Belgian towns aged between 45 and 64 years were invited for a cardiovascular check-up and blood test. Of all the attending persons without a history of cardiovascular disease (n = 898), 51% received at least one prescription, diet or health advice: 28% for hyperlipidaemia, 23% for physical activity, 22% for caloric intake, 9% for blood sugar, 5% for blood pressure and 4% for smoking. Interventions on lipoproteins, blood sugar and smoking habits were significantly more often proposed to persons with a medium or high cardiovascular risk compared to those at low cardiovascular risk. For persons at low cardiovascular risk, therapeutic lifestyle changes are often not advised, and isolated risk factors often remain untreated.

Blood Glucose↗
PubMed2002

Assessing the impact of complications on the costs of Type II diabetes.

AIMS/HYPOTHESIS: 'The Cost of Diabetes in Europe - Type II (CODE-2) study' provides the first coordinated attempt to assess the total costs of managing people with Type II (non-insulin-dependent) diabetes mellitus in Europe. Type II diabetes is associated with a number of serious long-term complications, which are a major cause of morbidity, hospitalisation and mortality in diabetic patients. METHODS: Patients were divided into four broad categories defining their complication status in terms of no complications, one or more microvascular complications, one or more macrovascular complications or one or more of each microvascular and macrovascular complication. The prevalence of complications and associated costs were assessed retrospectively for 6 months. RESULTS: In total, 72% of patients in the CODE-2 study had at least one complication, with 19% having microvascular only, 10% having macrovascular only and 24% of the total having both microvascular and macrovascular complications. Of patients with microvascular complications, 28% had neuropathy, 20% renal damage, 20% retinopathy and 6.5% required treatment for eye complications. Among the patients with macrovascular complications, 18% had peripheral vascular disease, 17% angina, 12% heart failure and 9% had myocardial infarction. Percutaneous transluminal coronary angioplasty, coronary artery bypass graft or stroke occurred in 3%, 4% and 5% of the patients, respectively. In patients with both microvascular and macrovascular complications, the total cost of management was increased by up to 250% compared to those without complications. CONCLUSION/INTERPRETATION: Complications have a substantial impact on the costs of managing Type II diabetes. This study has confirmed that the prevention of diabetic complications will not only benefit patients, but potentially reduce overall healthcare expenditure.

Amputation, Surgical↗
PubMed2002

Nateglinide improves glycaemic control when added to metformin monotherapy: results of a randomized trial with type 2 diabetes patients.

AIMS/HYPOTHESIS: This study evaluated the addition of nateglinide, a d-phenylalanine derivative that restores early phase insulin release, to metformin in type 2 diabetes patients stabilized on high-dose metformin. METHODS: This multicentre, double-blind, parallel group trial included 467 metformin-treated patients with glycosylated haemoglobin (HbA1c) between 6.8% and 11%. Patients were randomized to add nateglinide 60 mg, 120 mg or placebo before three meals to metformin 1000 mg b.i.d. for 24 weeks. RESULTS: HbA1c was significantly reduced with nateglinide 60 mg and 120 mg plus metformin compared with metformin control (-0.36%, p = 0.003; -0.59%, p < 0.001 respectively). Greater benefits occurred if patients had elevated HbA1c at baseline (-1.38% with nateglinide 120 mg in patients with HbA1c > 9.5%). A modest fasting plasma glucose reduction was observed. Most symptoms suggestive of hypoglycaemia occurred in patients with low HbA1c levels (<or= 8%) at baseline, although no confirmed cases of hypoglycaemia occurred with nateglinide 60 mg in this patient group. Events suggestive of hypoglycaemia were confirmed in 1.1% of cases (plasma glucose <or= 3.3 mmol/l). Weight gain over 24 weeks was 0.9 kg with nateglinide 120 mg vs. metformin alone, and plasma lipids remained unchanged. CONCLUSIONS/INTERPRETATION: In patients stabilized on high-dose metformin, the addition of nateglinide improved glycaemic control. The combination of these agents was well tolerated and both doses of nateglinide proved effective. The efficacy of nateglinide 60 mg and the low rate of hypoglycaemia observed at this dose make it suitable for patients close to their therapeutic target on metformin monotherapy.

Aged↗
PubMed2002

Obesity.

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Cardiovascular Diseases↗
PubMed2001

Predictors of weight loss and maintenance during 2 years of treatment by sibutramine in obesity. Results from the European multi-centre STORM trial. Sibutramine Trial of Obesity Reduction and Maintenance.

BACKGROUND: In this report we assess pre-treatment determinants of weight loss and maintenance outcome in The Sibutramine Trial of Obesity Reduction and Maintenance (STORM), a 2 y randomized, double-blind, placebo-controlled, European multicenter study examining the effect of sibutramine (Sib) on inducing and maintaining weight loss in obese subjects. MATERIAL: A total of 605 obese patients (BMI: 30-45 kg/m2) of both gender were included from eight European centers and treated for 24 months. The patients were treated for the initial 6 months by Sib (10 mg/day) and a low-fat low-energy, individualized diet (600 kcal/day deficit). The 467 patients who achieved >5% weight loss after 6 months were randomized 3&ratio;1 to Sib (10 mg/day) (Sib/Sib) and placebo (Sib/Pla) for weight maintenance over a further 18 months. MAIN OUTCOME AND ANALYSES: Pre-treatment individual characteristics were assessed as predictors of 6 months weight loss (kg) and 24 months weight maintenance using simple and multivariate correlation and regression analyses. RESULTS: In univariate analyses, the 6 month weight loss (n=505) was positively associated with pre-treatment body weight (r=0.27), height (r=0.18), fat-free mass (r=0.21) (all P<0.001), fat mass (r=0.13, P<0.03), and resting metabolic rate (r=0.13, P<0.003). However, no relation was found with age, gender, smoking status, age at onset of obesity, or number of previous slimming attempts. The same predictors were found for weight change to endpoint in the Sib/Sib group (n=350), while no predictors were identified in the Sib/Pla (n=114). In the multivariate regression analysis only pre-treatment body weight predicted weight loss at 6 months (P<0.001). Weight change (kg) to 24 month was predicted by: 4.34+0.07*body weight (kg)-4*treatment (Sib=1, Pla=0)-0.06*age (y), (r2=8%, P<0.001). CONCLUSION: Only pre-treatment body weight seems to be an important independent predictor of 6 months weight loss and 24 month weight maintenance in this study on diet and Sib. As only 8% of the variation in 24 months weight change could be explained by the predictors, the clinical value of this information is limited.

Adolescent↗
PubMed2001

The effects of orlistat on weight and on serum lipids in obese patients with hypercholesterolemia: a randomized, double-blind, placebo-controlled, multicentre study.

OBJECTIVE: Assessment of the effects of orlistat 120 mg three times daily vs placebo on weight loss and serum lipids in obese hypercholesterolemic patients. DESIGN: A 24 week multicentre, double-blind, randomized, placebo-controlled trial. After a 2-week single-blind run-in period (placebo+diet (-600 kcal/day; < or =30% of calories as fat)), 294 patients were submitted to the hypocaloric diet and randomly assigned to either orlistat 120 mg or placebo three times daily. Patients who completed the double-blind study (n=255) were eligible for participation in a subsequent 24 week open-label orlistat extension phase. SUBJECTS: Patients with body mass index (BMI) 27-40 kg/m2 and hypercholesterolemia (low-density-lipoprotein cholesterol, LDL-C, 4.1-6.7 mmol/l). MEASUREMENTS: Efficacy assessments included weight loss, lipid levels, other cardiovascular risk factors and anthropometric parameters. Safety assessments. RESULTS: Weight loss during run-in was similar in both groups. After randomization, orlistat-treated patients lost significantly more weight than placebo recipients: mean percentage weight loss from start of run-in to week 24 was-6.8% in the orlistat group and -3.8% in the placebo group (P<0.001). Moreover, more patients in the orlistat group than in the placebo group achieved clinically meaningful weight loss of > or =5% (64 vs 39%) or > or =10% (23 vs 13%) at week 24. Treatment with orlistat was associated with significantly greater changes in total cholesterol (-11.9% vs -4.0%; P<0.001) and LDL-C (-17.6 vs -7.6%; P<0.001). For any category of weight loss during the double-blind treatment period, change in LDL-C was more pronounced in orlistat-treated patients than in placebo recipients, indicating that orlistat had a direct cholesterol-lowering effect that was independent of weight reduction (P<0.001). Adjunction of orlistat during the extension phase in patients who initially received placebo induced a further decrease in weight, total cholesterol and LDL-C. Orlistat was generally well tolerated with a safety profile comparable to placebo, with the exception of a higher incidence of gastrointestinal events (> or =1 event in 64 vs 38% of patients). CONCLUSION: Orlistat as an adjunct to dietary intervention promotes weight loss and reduces LDL-C beyond the effect of weight loss in overweight or obese patients with concomitant hypercholesterolemia.

Adolescent↗
PubMed2001

Miglitol combined with metformin improves glycaemic control in type 2 diabetes.

AIM: To investigate the efficacy and safety of miglitol vs. placebo in type 2 diabetic outpatients insufficiently controlled (HbA1c between 7.5 and 10.5%) with diet and metformin. METHODS: Patients treated with diet and metformin (1500-2250 mg/day) were randomized to receive additional treatment with either miglitol or placebo for 32 weeks. The dosages were force-titrated: 4 weeks at 25 mg miglitol t.i.d., 12 weeks at 50 mg miglitol t.i.d., and 16 weeks at 100 mg miglitol t.i.d. or matching placebo. If the highest dosage could not be tolerated, patients could be down-titrated to 50 mg t.i.d. The primary efficacy criterion was the change in glycated haemoglobin (HbA1c). Secondary efficacy parameters included fasting and 1 h postprandial blood glucose, serum insulin, and fasting and 1 h postprandial triglyceride levels. Safety and tolerability were evaluated by the incidence of adverse events and changes in vital signs or routine biochemical and haematological parameters. RESULTS: One hundred and fifty-two patients were valid for the intent-to-treat (ITT) analysis. There was a significant decrease in HbA1c on adding miglitol to metformin compared to adding placebo (miglitol treatment effect, - 0.21%; placebo treatment effect, + 0.22%; p = 0.011). Postprandial blood glucose declined in both the miglitol/metformin and placebo/metformin groups with a statistically significant difference in favour of miglitol/metformin (end of treatment adjusted means 13.8 mmol/l for miglitol vs. 15.8 mmol/l for placebo, p = 0.0007). Adverse events (AEs) were reported by only 8% more patients in the miglitol/metformin group than placebo/metformin. No cases of hypoglycaemia were reported. CONCLUSIONS: Miglitol can safely and effectively be added to diet and metformin in patients whose type 2 diabetes is insufficiently controlled, and improves glycaemic control by significantly reducing HbA1c and postprandial blood glucose levels.

1-Deoxynojirimycin↗
PubMed2001

Visceral fat is a determinant of PAI-1 activity in diabetic and non-diabetic overweight and obese women.

Plasminogen activator inhibitor type 1 (PAI-1), an inhibitor of fibrinolysis and an important and independent cardiovascular risk factor, has been shown to be elevated in obesity and type 2 diabetes. Recent study results have suggested that adipose tissue--visceral fat in particular--could play an important role in the fibrinolytic process.In order to assess the specific role of this fat distribution, we measured PAI-1 activity (AU/ml) and visceral fat (CT-scan at level L4-L5) in 2 groups of 30 overweight and obese diabetic and overweight and obese non-diabetic women. Subjects were matched for age, weight, body mass index, fat mass and total abdominal fat. Visceral adipose tissue and PAI-1 were significantly higher in diabetic women (p = 0.022 and p = 0.004 respectively) than in non-diabetic patients. Visceral fat correlated significantly with PAI-1 activity, even after correction for insulin and triglycerides (r = 0.28, p = 0.034). Stepwise regression analysis showed visceral fat as the most important determinant factor for PAI-1 in the whole group and in the non-diabetic group. In the diabetic group, fasting insulin was the most important determinant. These results show that visceral fat is more important than BMI or total body fat in the determination of PAI-1 levels. Furthermore, the increased amount of visceral fat in type 2 diabetics may contribute to the increase of PAI-1 activity levels and the subsequent increased risk for thrombovascular disease, regardless of BMI and total fatness.

Abdomen↗
PubMed2001

Leptin receptor gene polymorphisms are associated with insulin in obese women with impaired glucose tolerance.

Leptin receptors are present on beta-cells as well as on muscle and fat cells, thus enabling leptin to modulate both insulin secretion and insulin action. Leptin inhibits especially the glucose-stimulated insulin secretion from pancreatic cells. The leptin receptor (LEPR) gene could thus play a role in the regulation of glucose and insulin after an oral glucose load. Therefore, the relationship between LEPR polymorphisms and glucose and insulin response to an oral glucose tolerance test (OGTT) was investigated. Three LEPR polymorphisms (Lys(109)Arg, Gln(223)Arg, and Lys(656)Asn) were typed on genomic DNA of 358 overweight and obese women, aged 18-60 yr. Based on an OGTT, 269 subjects were defined with normal glucose tolerance, and 89 with impaired glucose tolerance (IGT). Associations between genotypes and glucose metabolism were analyzed with a general linear models procedure in pre- and postmenopausal women separately, after adjusting the data for age and fat mass. In postmenopausal women with IGT (n = 24), associations were found with Lys(109)Arg and Lys(656)Asn for fasting insulin (P = 0.05) and with Lys(109)Arg and Gln(223)Arg for the insulin response to an OGTT (P < 0.02). In the same group, trends were found with Lys(656)Asn for fasting glucose as well as in response to the OGTT. In premenopausal women with IGT (n = 65), associations were found with Lys(109)Arg and Lys(656)Asn for overall glucose response to the glucose load. In contrast, no associations with insulin or glucose were found in women with normal glucose tolerance. In conclusion, these data indicate that LEPR polymorphisms are associated with insulin and glucose metabolism in women with impaired glucose homeostasis.

Adolescent↗
PubMed2000

Associations of leptin with body fat distribution and metabolic parameters in non-insulin-dependent diabetic patients: no effect of apolipoprotein E polymorphism.

Leptin levels have been shown previously to be associated with anthropometric parameters such as the body mass index (BMI), total body fat, and subcutaneous fat. Since apolipoprotein E (apoE) polymorphism is known to be a genetic marker affecting the relationship between certain anthropometric and metabolic parameters, we evaluated whether the leptin level and/or associations between the leptin level and body composition in non-insulin-dependent diabetic patients could be determined by apoE polymorphism. In 171 type 2 diabetic patients (105 male and 66 female), body composition (BMI, waist to hip ratio [WHR], fat mass, and visceral fat) was measured and fasting blood samples were obtained to determine the apoE genotype, leptin, glucose, and insulin levels, and the lipid profile. The mean leptin level for the whole group was 11.7 +/- 9.3 ng/mL, with a significant difference (P < .001) between men (7.1 +/- 4.9 ng/mL) and women (19.0 +/- 10.1 ng/mL). No difference was found for leptin levels or anthropometric variables between the 3 different apoE genotypes (E3/E3 homozygotes, E2 carriers, and E4 carriers). Only low-density lipoprotein (LDL) cholesterol was significantly different between the 3 apoE subgroups. The correlations of leptin with anthropometric variables, especially visceral fat, tended to be different between the 3 apoE groups, but this was not independent and no effect was found after controlling for the other parameters in the model. A multiple regression model containing gender, subcutaneous fat, fasting glucose, triglycerides, and high-density lipoprotein (HDL) cholesterol explained 81% of the variance in leptin levels. We conclude that apoE polymorphism has no effect on the leptin level or its associations with other anthropometric and metabolic parameters.

Apolipoproteins E↗
PubMed2000

High frequency of persisting or increasing islet-specific autoantibody levels after diagnosis of type 1 diabetes presenting before 40 years of age. The Belgian Diabetes Registry.

OBJECTIVE: To study the presence and levels of GAD65 antibodies (GADA), IA-2 antibodies (IA-2-A), and islet cell antibodies (ICA) during the first years after clinical onset of type 1 diabetes in relation to age at diagnosis. RESEARCH DESIGN AND METHODS: Type 1 diabetic patients (n = 194) <40 years of age were consecutively recruited at the time of diagnosis by the Belgian Diabetes Registry and followed during the first 4 years of insulin treatment. ICA were determined by indirect immunofluorescence assay and IA-2-A, GADA, and insulin autoantibodies by a radioligand assay. RESULTS: Overall, 94% of initially antibody-positive patients (n = 180) remained positive for at least 1 antibody type 4 years after diagnosis. In the case of diagnosis after 7 years of age, GADA, IA-2-A, and ICA persisted in 91, 88, and 71%, respectively, of the initially antibody-positive patients. Antibody persistence was lower in those diagnosed at <7 years of age, amounting to 60% for GADA, 71% for IA-2-A, and 39% for ICA. In 57% of the initially antibody-positive patients, at least 1 type of autoantibody reached peak values after diagnosis. This occurred more frequently for clinical onset after 7 years of age and more often for GADA (49%) than for IA-2-A (29%) or ICA (19%). Of the patients, 24% that were negative for GADA at onset became GADA-positive during the following 4 years. Among the 7% initially antibody-negative patients, 2 of 14 subjects developed antibodies after clinical onset. CONCLUSIONS: In particular, for diagnosis after 7 years of age, islet cell-specific autoantibodies generally persist for many years after diagnosis. There is also a high frequency of increasing antibody levels and of conversion to antibody positivity in the first 4 years after diagnosis and start of insulin treatment. Thus, determination of antibodies at diagnosis can underestimate the number of cases with autoimmune type 1 diabetes, in particular with assays of lower sensitivity. The divergent temporal patterns of ICA, GADA, and IA-2-A suggest that the ICA test recognizes other antibody specificities besides GADA and IA-2-A and reflects other autoimmune processes; it also indicates that GADA assays have a higher diagnostic sensitivity in the period after clinical onset.

Adolescent↗