Biomedical subjects

Luc Van Gaal

Publications and source records attributed to Luc Van Gaal.

12 recordsLinked to original sources

PubMed2006

Sleep-disordered breathing in overweight and obese children and adolescents: prevalence, characteristics and the role of fat distribution.

AIMS: To determine the prevalence of sleep-disordered breathing (SDB) in a clinical sample of overweight and obese children and adolescents, and to examine the contribution of fat distribution. METHODS: Consecutive subjects without chronic lung disease, neuromuscular disease, laryngomalacia, or any genetic or craniofacial syndrome were recruited. All underwent measurements of neck and waist circumference, waist-to-hip ratio, % fat mass and polysomnography. Obstructive apnoea index > or =1 or obstructive apnoea-hypopnoea index (OAHI) > or =2, further classified as mild (2< or =OAHI<5) or moderate-to-severe (OAHI> or =5), were used as diagnostic criteria for obstructive sleep apnoea (OSA). Central sleep apnoea was diagnosed when central apnoeas/hypopnoeas > or =10 s were present accompanied by >1 age-specific bradytachycardia and/or >1 desaturation <89%. Subjects with desaturation < or =85% after central events of any duration were also diagnosed with central sleep apnoea. Primary snoring was diagnosed when: snoring was detected by microphone and normal obstructive indices and saturation. RESULTS: 27 overweight and 64 obese subjects were included (40 boys; mean (standard deviation (SD)) age 11.2 (2.6) years). Among the obese children, 53% were normal, 11% had primary snoring, 11% had mild OSA, 8% had moderate-to-severe OSA and 17% had central sleep apnoea. Half of the patients with central sleep apnoea had desaturation <85%. Only enlarged tonsils were predictive of moderate-to-severe OSA. On the other hand, higher levels of abdominal obesity and fat mass were associated with central sleep apnoea. CONCLUSION: SDB is very common in this clinical sample of overweight children. OSA is not associated with abdominal obesity. On the contrary, higher levels of abdominal obesity and fat mass are associated with central sleep apnoea.

Adiposity↗

PubMed2006

Body surface area in normal-weight, overweight, and obese adults. A comparison study.

Values for body surface area (BSA) are commonly used in medicine, particularly to calculate doses of chemotherapeutic agents and index cardiac output. Various BSA formulas have been developed over the years. The DuBois and DuBois (Arch Intern Med 1916;17:863-71) BSA equation is the most widely used, although derived from only 9 subjects. More recently, Mosteller (N Engl J Med 1987;317:1098) produced a simple formula, [weight (kg) x height (cm)/3600](1/2), which could be easily remembered and evaluated on a pocket calculator, but validation data in adults are rare. The purpose of the present study was to examine the BSA based on Mosteller's formula in normal-weight (body mass index [BMI], 20-24.9 kg/m(2)), overweight (BMI, 25-29.9 kg/m(2)), and obese (BMI, >/=30 kg/m(2)) adults (>18 years old) in comparison with other empirically derived formulas (DuBois and DuBois, Boyd [The growth of the surface area of the human body. Minneapolis: University of Minnesota Press; 1935], Gehan and George [Cancer Chemother Rep 1970;54:225-35], US Environmental Protection Agency [Development of statistical distributions or ranges of standard factors used in exposure assessments Washington, EPA/600/8-85-010. Office of Health and Environmental Assessment; 1985), Haycock et al [J Pediatr 1978;93:62-6], Mattar [Crit Care Med 1989;17:846-7], Livingston and Scott [Am J Physiol Endocrinol Metab 2001;281:E586-91]) and with the new 3-dimensional-derived formula of Yu et al (Appl Ergon. 2003;34:273-8). One thousand eight hundred sixty-eight patients were evaluated (397 normal weight [BMI, 23 +/- 1 kg/m(2); age, 50 +/- 14 years; M/F, 289/108], 714 overweight [BMI, 27 +/- 1 kg/m(2); age, 52 +/- 11 years; M/F, 594/120], and 757 obese [BMI, 36 +/- 6 kg/m(2); age, 53 +/- 11 years; M/F, 543/215]). The overall BSA was 2.04 +/- 0.24 m(2): 1.81 +/- 0.19 m(2) in normal-weight, 1.99 +/- 0.16 m(2) in overweight, and 2.21 +/- 0.22 m(2) in obese subjects. These values were significantly higher in overweight and obese patients compared with the values using the DuBois-DuBois formula (overall, 2.00 +/- 0.22 m(2), P < .01; normal weight, 1.81 +/- 0.19 m(2), P = .93; overweight, 1.97 +/- 0.16 m(2), P < .01; obese, 2.14 +/- 0.21 m(2), P < .001). We could show an excellent correlation between the results obtained from each formula, with all correlations of 0.97 or higher (between 0.971 and 0.999). Body surface area prediction with the commonly used DuBois formula underestimated BSA in obese patients by as much as 3% (male) to 5% (female). Based on the formula of Yu et al, however, BSA is overestimated when these traditional formulas are used. Although Mosteller's formula is recommended based on its simplicity and suitability for laboratory and clinical work in adults, accuracy studies in whites with 3-dimensional one-pass whole-body scanning are needed.

Adult↗

PubMed2006

Intensive insulin therapy in the intensive care unit: assessment by continuous glucose monitoring.

OBJECTIVE: Hyperglycemia occurs in most critically ill patients. Using continuous glucose monitoring (CGM), we investigated whether intensive insulin therapy based on discontinuous glucose monitoring can achieve normoglycemia (80-110 mg/dl) in a medical intensive care unit (MICU). RESEARCH DESIGN AND METHODS: Fifty adults (men/women 31/19, age 62 +/- 16 years, nondiabetic/diabetic 30/20, intravenous/subcutaneous insulin 22/28, and Acute Physiology and Chronic Health Evaluation II score 22 +/- 7) were prospectively recruited. Forty-eight-hour CGM was performed using a subcutaneous glucose sensor (GlucoDay) and compared with arterial glycemia. Main outcome measures were percent of time in normoglycemia and accuracy/applicability of CGM. RESULTS: During 48-h CGM, glycemia reached target (80-110 mg/dl) in only 22 +/- 18%, was >140 mg/dl in 39 +/- 27%, and was <60 mg/dl in 5 +/- 10% of the time. Patients on subcutaneous versus intravenous insulin had more glycemia readings >110 mg/dl (P = 0.016). Glycemia was higher in diabetic patients (170 +/- 77 vs. 129 +/- 35 mg/dl, P = 0.013). BMI was an independent determinant for bad glycemic control (beta = 0.73, P < 0.0001). Diabetic state (beta = 0.47, P < 0.0001), septic shock (beta = 0.22, P = 0.045), sequential organ failure assessment score (beta = 0.40, P = 0.001), and use of corticoids (beta = 0.28, P = 0.014) and inotropics (beta = -0.24, P = 0.035) were independent determinants of insulin dose. GlucoDay values and arterial glycemia correlated well (r = 0.85, P < 0.0001, n = 555 after six-point calibration), with 97% of data falling in regions A and B of error grid analysis. There were no adverse events using GlucoDay. CONCLUSIONS: GlucoDay, a well-tolerated 48-h CGM system, revealed that normoglycemia was only achieved 22% of the time in MICU patients. Further studies should investigate whether application of CGM to titrate insulin therapy can improve patient outcome.

Blood Glucose↗

PubMed2005

Flow mediated dilatation and cardiac function in type 1 diabetes mellitus.

The present study sought to examine the occurrence of subclinical markers of cardiovascular risk and cardiac dysfunction with increasing disease duration in type 1 diabetes mellitus (DM). There are few data on subclinical cardiovascular abnormalities in type 1 DM. The study included 100 patients without any cardiovascular complaints (mean age 46.6 years, range 22 to 63), with a history of type 1 DM ranging from 2 to 36 years, and 75 age-matched controls. Standard 2-dimensional and Doppler echocardiography and pulse-wave tissue Doppler (tD) mapping of systolic (Sm) and diastolic (Em, Am) velocities (12 left ventricular [LV] segments and right-sided cardiac) were performed. An Em/Am ratio of <1 was considered to represent abnormal segmental diastolic function. Flow-mediated dilation (FMD) of the brachial artery, carotid intima media thickness (IMT) measurement, and extensive laboratory analysis were performed. The FMD was reduced, and IMT increased in patients (p < 0.01). Regional tD-derived diastolic and systolic functional abnormalities were observed within the first decade of the disease. Significant correlations were found between FMD and LV segments with tD-derived dysfunction, the duration of DM, and fibrinogen (p < 0.0001 for all). Stepwise regression analysis showed that FMD was the strongest predictor of abnormal segmental function (p < 0.0001). Data further presented as an analysis of tertiles by DM duration show an increasing occurrence of subclinical cardiac dysfunction and cardiovascular risk markers compared with age-matched controls. In conclusion, FMD is associated with abnormal segmental cardiac function in type 1 DM.

Adult↗

PubMed2005

Nicotinic acid in the management of dyslipidaemia associated with diabetes and metabolic syndrome: a position paper developed by a European Consensus Panel.

Individuals with type 2 diabetes and metabolic syndrome are at markedly increased risk of cardiovascular morbidity and mortality. The increasing prevalence of both conditions poses a major challenge for clinicians in the 21st century. Both diabetes and metabolic syndrome are associated with a clustering of cardiovascular risk factors. In particular, dyslipidaemia characterised by low plasma levels of high-density lipoprotein cholesterol (HDL-C), elevated triglycerides and an increase in small, dense low-density lipoprotein (LDL) particles (the lipid triad), has been established as the most important modifiable risk factor for coronary heart disease (CHD). Current treatment guidelines recognise the increased CHD risk associated with diabetes and metabolic syndrome and focus on LDL-C lowering with statin treatment, in addition to dietary and lifestyle modification, as the primary lipid-modifying therapy. However, while there is no doubt that statin therapy significantly reduces CHD risk in these patients, their residual absolute risk remains higher than in individuals without diabetes or metabolic syndrome. Thus, there is a clear need to target other aspects of lipoprotein metabolism, notably low HDL-C and hypertriglyceridaemia, to further reduce CHD risk. Combining statin therapy (targeting LDL-C) with interventions that also modify low HDL-C and elevated triglycerides could be a useful strategy to optimise CHD risk reduction. Cautious combination of a fibrate or nicotinic acid with a statin is useful for the management of combined dyslipidaemia. Nicotinic acid is the more potent agent for raising HDL-C (by up to 29% at clinically recommended doses). It also substantially reduces triglycerides and LDL-C, and promotes a shift from small, dense LDL to larger, more buoyant LDL particles. Preliminary clinical data suggest that combining nicotinic acid with a statin will produce a greater reduction in cardiovascular risk in patients with diabetes and metabolic syndrome than statin monotherapy alone. Nicotinic acid is also safe for use in patients with diabetes, with no evidence of clinically relevant deterioration in glycaemic control at recommended doses (< or = 2 g/day). On review of the available evidence, this European Consensus Panel recommends the combination of nicotinic acid and a statin, together with lifestyle modification, as a useful strategy to lower CHD risk in patients with diabetes and metabolic syndrome. Prolonged-release nicotinic acid with improved tolerability compared with previous formulations may have obvious advantages for use in this setting.

Cardiovascular Diseases↗

PubMed2004

Impact of Vitamin E supplementation on lipoprotein peroxidation and composition in Type 1 diabetic patients treated with Atorvastatin.

OBJECTIVE: To investigate the impact of Vitamin E on lipids and peroxidation during statin treatment. RESEARCH DESIGN AND METHODS: T1DM patients with high cholesterol received Atorvastatin 20mg with either placebo (group AP, n = 11) or d-alpha-tocopherol 750 IU (group AE, n = 11) daily. They were monitored for blood biochemistry, low-density lipoprotein (LDL) subfractions and lipid peroxidation at inclusion and after 3 and 6 months. RESULTS: Serum cholesterol and triglycerides decreased to the same extent (29 and 21% respectively) in both groups. Serum tocopherol decreased by 18% in AP and increased by 50% in AE (P < 0.0001, between-group comparison by repeated measures ANOVA) but relative to lipids it increased by 15% in AP and by 100% in AE. Copper-induced production of thiobarbituric reactive substances in the LDL + VLDL fraction increased by 18% in AP and did not change in AE (P = 0.02). The lagtime for the production of fluorescent products was prolonged by 13 min only in group AE (P = 0.028). Plasma malondialdehyde decreased by 35% in both groups (P = 0.002) but not when adjusted for lipids. CONCLUSIONS: In T1DM Vitamin E supplements do not affect the lowering of lipids and plasma malondialdehyde achieved by Atorvastatin. They reverse the increase of in vitro peroxidation caused by Atorvastatin but do not achieve the decreases observed in patients not receiving lipid-lowering drugs. These results indicate that the antioxidant effect of Vitamin E is attenuated when given in conjunction with this statin.

Adult↗

PubMed2004

Evolution of serum alpha-tocopherol in the postprandial and postabsorptive phases in type 1 diabetes mellitus.

Blood glucose, lipids, alpha-tocopherol, and malondialdehyde were monitored in type 1 diabetes mellitus patients for 8 hours after a standard fat-rich breakfast and lunch. Although glucose and triglycerides increased, alpha-tocopherol decreased and malondialdehyde increased in the postprandial phase. In the postabsorptive phase values returned to fasting levels. These results point to the possible relevance of postprandial alpha-tocopherol depletion and lipid peroxidation to an increased cardiovascular risk in these patients.

Absorption↗

PubMed2004

Long term magnesium supplementation influences favourably the natural evolution of neuropathy in Mg-depleted type 1 diabetic patients (T1dm).

Chronic Mg depletion in T1dm has been linked to polyneuropathy (PNP). Short term Mg supplementation has suggested a decrease in pathological EMG signs typical for PNP. The aim of this study is to determine if long term supplementation under stable metabolic control can normalize the Mg status and influence the natural evolution of PNP. 110 T1dm (60 M,50 W) with chronic Mg depletion (erythrocyte Mg < 2.3 mMol/l) were randomised to receive 300 mg Mg++ daily or no supplement for a period of 5 years. Follow-up was organized by the same diabetologist: HbA1c, renal function and Mg status every 3 months, electromyography (EMG) and clinical neurological control with staging every year. Drop-out was decided for recurrent DKA, diseases or drugs interfering with Mg status or side-effects of Mg treatment. 97 patients (53 M,44 W) finished the study: 49 (27 M,22W) were supplemented (group A) and 48 (26 M,22 W) served as controls (group B). At the start there were no significant differences between both groups. HbA1c after 5 years (A:7.80% sd 0.80, B:7.75% sd 0.75) was not significantly different from the start. Erythrocyte Mg (Mg rbc) rose significantly (p < 0.0001) in group A to normal levels but remained low in group B. Staging of PNP after 5 years shows a decrease in 39%, statu quo in 49% and a worsening in 12% in group A and 8,31 and 61% respectively in group B (Fisher Exact test: p < 0.0001). Normalization of EMG signs was only seen in incipient PNP. Logistic regression analysis shows that longer duration of diabetes (p < 0.006) and low Mgrbc (p < 0.05) are the major determinants of PNP evolution. Under stable metabolic control long term Mg supplementation is able to restore a normal Mg status and influence favourably the natural evolution of PNP as compared to non supplemented T1dm controls.

Adult↗

PubMed2002

Relation between disease phenotype and HLA-DQ genotype in diabetic patients diagnosed in early adulthood.

We investigated inaugural disease phenotype in relation to the presence or absence of diabetes-associated autoantibodies and human leukocyte antigen (HLA) DQ risk genotypes in adult-onset diabetic patients. Blood samples and questionnaires were obtained from 1584 recent-onset Belgian Caucasian patients (age 15-39 yr at diagnosis of primary diabetes) who were recruited by the Belgian Diabetes Registry over an 11-yr period. At clinical diagnosis, antibody-positive patients (n = 1198) were on average younger and had more symptoms, a more acute disease onset, lower body mass index, and random C-peptide levels, but higher insulin needs, glycemia, and prevalence of ketonuria, HLA-DQ, and 5' insulin gene susceptibility genotypes (P < 0.001 vs. antibody-negative patients; n = 386). In antibody-positive patients, these characteristics did not differ according to HLA-DQ genotype. However, in antibody-negative subjects, we found that patients were younger (P = 0.001); had a lower body mass index (P < 0.001), higher insulin needs (P = 0.014), and amylasemia (P = 0.001); and tended to have a higher glycemia and lower C-peptide in the presence of susceptible HLA-DQ genotypes. Differences according to HLA-DQ genotype subsisted after careful age-matching. In conclusion, we found no relation between initial disease phenotype and HLA-DQ genotype in antibody-positive diabetic young adults. In contrast, antibody-negative patients displayed more type 1-like features when carrying susceptible HLA-DQ genotypes known to promote the development of antibody-positive diabetes. The overrepresentation of these susceptibility genotypes in antibody-negative patients suggests the existence of an immune-mediated disease process with as yet unidentified immune markers in a subgroup of seronegative patients.

Adolescent↗

PubMedDate not supplied

Postprandial glucose monitoring in type 1 diabetes mellitus: use of a continuous subcutaneous monitoring device.

BACKGROUND: Pre-prandial glucose gives insufficient information on glycemic excursions throughout the day. We aimed to test a continuous subcutaneous glucose-monitoring device (GlucoDay) to describe postprandial glucose changes. METHODS: In 23 T1DM patients, 24-h GlucoDay registrations were started about 14 h before receiving a standard breakfast B and 3 h later lunch L. RESULTS: The 3-min glucose values were computed into parameters describing the postprandial changes after B and L. Two-hour glucose was higher after B (243 +/- 69 vs 180 +/- 79 mg/dL after L, p < 0.0001). Maximum glycemia (313 +/- 105 mg/dL after B and 304 +/- 119 after L, p < 0.0001) was higher and was reached after 78 and 57 min respectively. Three-hour AUC was higher but 30-min AUC was lower after B (5725 +/- 2414 vs 7488 +/- 2208 min mg/dL after L, p = 0.004). Glucose spikes (maximum peak minus fasting plasma glucose) were similar after B and L but the difference between maximum and minimum values was smaller after B (165 +/- 110 vs 219 +/- 115 mg/dL after L, p = 0.020). Duration of hyperglycemic periods >200, 140 or 126 mg/dL were not different after B or L, but time spent at glucose <100 mg/dL was longer after L (p < 0.0001). CONCLUSIONS: These results illustrate the use of subcutaneous glucose registration to characterize postprandial glycemia patterns in T1DM. Application of such methods to evaluate this and other clinical situations in DM can lead to therapeutic and dietary adjustments and ultimately improve glycemic control.

Adult↗

PubMedDate not supplied

Impact of diabetes mellitus on the relationships between iron-, inflammatory- and oxidative stress status.

BACKGROUND: Diabetes is an inflammatory condition associated with iron abnormalities and increased oxidative damage. We aimed to investigate how diabetes affects the interrelationships between these pathogenic mechanisms. METHODS: Glycaemic control, serum iron, proteins involved in iron homeostasis, global antioxidant capacity and levels of antioxidants and peroxidation products were measured in 39 type 1 and 67 type 2 diabetic patients and 100 control subjects. RESULTS: Although serum iron was lower in diabetes, serum ferritin was elevated in type 2 diabetes (p = 0.02). This increase was not related to inflammation (C-reactive protein) but inversely correlated with soluble transferrin receptors (r = - 0.38, p = 0.002). Haptoglobin was higher in both type 1 and type 2 diabetes (p < 0.001) and haemopexin was higher in type 2 diabetes (p < 0.001). The relation between C-reactive protein and haemopexin was lost in type 2 diabetes (r = 0.15, p = 0.27 vs r = 0.63, p < 0.001 in type 1 diabetes and r = 0.36, p = 0.001 in controls). Haemopexin levels were independently determined by triacylglycerol (R(2) = 0.43) and the diabetic state (R(2) = 0.13). Regarding oxidative stress status, lower antioxidant concentrations were found for retinol and uric acid in type 1 diabetes, alpha-tocopherol and ascorbate in type 2 diabetes and protein thiols in both types. These decreases were partially explained by metabolic-, inflammatory- and iron alterations. An additional independent effect of the diabetic state on the oxidative stress status could be identified (R(2) = 0.5-0.14). CONCLUSIONS: Circulating proteins, body iron stores, inflammation, oxidative stress and their interrelationships are abnormal in patients with diabetes and differ between type 1 and type 2 diabetes.

Adult↗

PubMedDate not supplied

Are all glitazones the same?

This supplement focuses on the benefits of targeting insulin resistance through therapy with a new class of oral antidiabetic agents, the thiazolidinediones (TZDs) or 'glitazones'. There are important differences between the three TZD class members that warrant discussion to enable physicians to make rational and informed therapeutic choices between the agents. Overall the TZDs appear to be similar in their effects on blood glucose, as all class members have demonstrated effective glycaemic control, both as monotherapy and in combination with sulphonylureas, metformin or exogenous insulin. The safety profiles of the three agents are more diverse, with what appear to be 'TZD class effects', (probably mediated via activation of peroxisome proliferator-activated receptor gamma [PPAR gamma]) and 'TZD-specific effects', which are unique to each agent and may be a consequence of differing chemical structures. While rosiglitazone and pioglitazone share some class effects with troglitazone, they have several characteristics that define them as unique agents. By tackling the control of type 2 diabetes through direct effects on insulin resistance, the TZDs represent an important new therapeutic tool for healthcare professionals.

Chromans↗