De Bruyne P.,Ghent University |
De Guchtenaere A.,Zeepreventorium |
Van Herzeele C.,Ghent University |
Raes A.,Ghent University |
And 4 more authors.
European Journal of Pediatrics | Year: 2014
Desmopressin 120 μg oral lyophilisate and 200 μg tablet are considered bioequivalent, based on extrapolation of studies in a limited number of adults and on one dose-finding study of desmopressin oral lyophilisate in children. However, no comparative pharmacokinetic study in children was executed confirming this statement. No data are available on the influence of food intake on the bioavailability of desmopressin tablet in a pediatric setting, although studies in adults have documented that food intake results in a significantly lower desmopressin plasma concentration. In this study, we analyzed plasma concentrations of desmopressin oral lyophilisate and tablet with concomitant food intake. Twenty-three children with monosymptomatic nocturnal enuresis (mean age, 12.7 years) were recruited. Two tests were performed on two separate days in identical conditions with a standardized food and fluid intake. Desmopressin was administered as desmopressin tablet or desmopressin oral lyophilisate immediately after a meal. Desmopressin plasma concentration was measured at 1 h, 2 h, and 6 h postdosing. No significant difference in plasma concentration of 120 μg desmopressin oral lyophilisate and 200 μg tablet was demonstrated, even with concomitant food intake. A significant difference in variability was found, identifying a smaller variance for desmopressin oral lyophilisate plasma concentrations at all time points. This study demonstrates comparable plasma levels for desmopressin oral lyophilisate, despite the lower dose. The dosage for desmopressin oral lyophilisate is more predictable due to the significantly smaller variance. Therefore, desmopressin oral lyophilisate seems more suitable, especially in the younger age group for which time interval between dinner and drug administration is limited. © 2013 Springer-Verlag Berlin Heidelberg.
Verloigne M.,Ghent University |
De Bourdeaudhuij I.,Ghent University |
Tanghe A.,Zeepreventorium |
D'Hondt E.,Ghent University |
And 4 more authors.
International Journal of Behavioral Nutrition and Physical Activity | Year: 2011
Background: Within the Self-Determination Theory (SDT) framework, the first major study aim was to investigate the SDT tenets in an obese adolescent population by examining the factor structure of the Behavioural Regulation in Exercise Questionnaire-2 (BREQ-2) and by investigating associations between physical activity (PA) and motivation in obese adolescents. The second aim was to study differences in motivation according to adolescents' educational level, since lower educated obese adolescent are a sub-risk group for lower PA levels among the obese adolescents. The third aim was to investigate whether attending a residential obesity treatment program could lead to an increase in autonomous motivation towards PA and to see if the treatment effect on motivation was different in low versus high educated youth.Methods: For the first study aim, the sample comprised 177 obese adolescents at the start of a 10-month multidisciplinary residential obesity treatment program (BMI = 35.9 ± 6.0 kg/m2, 15.1 ± 1.5 years, 62% girls). A subsample of 65 adolescents (stratified by educational level) were divided into low (n = 34) versus high educated (n = 31) as part of the second and third study aim. Motivation was assessed using the BREQ-2 and PA using the Flemish Physical Activity Questionnaire.Results: Exploratory factor analysis showed sufficient validations with the original factor for 17 out of 19 BREQ-2 items. Significant positive correlations were found between PA and the composite score of relative autonomy (r = 0.31, p < 0.001), introjected (r = 0.23, p < 0.01), identified (r = 0.31, p < 0.001) and intrinsic regulation (r = 0.38, p < 0.001). Higher educated adolescents scored higher on the composite score of relative autonomy, introjected, identified and intrinsic regulation at the start of treatment (F = 3.68, p < 0.001). The composite score of relative autonomy, external, identified and intrinsic regulation significantly increased during treatment for all adolescents (F = 6.65, p < 0.001). Introjected regulation significantly increased for lower educated adolescents (F = 25.57, p < 0.001).Conclusions: The BREQ-2 can be used in an obese adolescent population. Higher levels of autonomous motivation towards PA were related to higher PA levels. Adolescents had increases in both autonomous and controlled forms of motivation during treatment. Special attention for lower educated adolescents during treatment is needed, as they have a lower autonomous motivation at the start of treatment and an increase in introjected regulation during treatment. © 2011 Verloigne et al; licensee BioMed Central Ltd.
Bruyndonckx L.,University of Antwerp |
Hoymans V.Y.,University of Antwerp |
Frederix G.,University of Antwerp |
De Guchtenaere A.,Zeepreventorium |
And 5 more authors.
Journal of Pediatrics | Year: 2014
Objective To examine the degree of microvascular endothelial dysfunction in relation to classical cardiovascular risk factors, arterial stiffness, and numbers of circulating endothelial progenitor cells (EPCs) and endothelial microparticles (EMPs), in obese and normal-weight children. Study design Cross-sectional study with 57 obese (15.2 ± 1.4 years) and 30 normal-weight children (15.4 ± 1.5 years). The principal outcome was microvascular endothelial function measured with peripheral arterial tonometry. Fasting blood samples were taken for biochemical analysis and EMPs (CD31 +/CD42b- particles) and EPCs (CD34+/KDR +/CD45dim/- cells) flow cytometry. Characteristics between groups were compared by use of the appropriate independent samples test; a stepwise multiple regression analysis was used to determine independent predictors of microvascular endothelial function. Results Microvascular endothelial function was significantly impaired in obese children and inversely correlated with body mass index Z scores (r = -0.249; P =.021) and systolic blood pressure (r = -0.307; P =.004). The number of EPCs was significantly lower in obese children and correlated with endothelial function (r = 0.250; P =.022), and the number of EMPs was significantly greater in obese children and correlated inversely with endothelial function (r = -0.255; P =.021). Multivariate analysis revealed that systolic blood pressure and numbers of circulating EPCs and EMPs are important determinants of endothelial function. Conclusion Obese children demonstrate impaired endothelial microvascular function, increased arterial stiffness, fewer EPCs, and more EMPs. Besides systolic blood pressure, EPC and EMP counts independently predict the presence of microvascular endothelial dysfunction. Copyright © 2014 Elsevier Inc. All rights reserved.
Van Hoorenbeeck K.,University of Antwerp |
Franckx H.,Zeepreventorium |
Debode P.,Zeepreventorium |
Aerts P.,University of Antwerp |
And 6 more authors.
Obesity | Year: 2012
Sleep-disordered breathing (SDB) is prevalent in childhood obesity. It may be an independent risk factor for the metabolic syndrome. Possible mechanisms are inflammation and oxidative stress. Adenotonsillectomy in childhood obesity is associated with a high recurrence rate and risk of postoperative weight gain. Therefore, this study assessed the effects of SDB on inflammation and oxidative stress in childhood obesity before and after weight loss. We included 132 obese subjects between 10 and 18 years consecutively. Median age was 15.4 years (10.1-18.0). Mean BMI z-score was 2.72 ± 0.42. Leukocytes and differentiation, high sensitivity C-reactive protein (hs-CRP), and uric acid (UA) were determined at baseline and subjects underwent a sleep assessment. SDB was diagnosed in 39%. Linear regression analysis showed an association between UAlog and oxygen desaturation indexlog (ODIlog) (r = 0.20; P = 0.03), between leukocytes log and respiratory disturbance index log (RDIlog) (r = 0.23; P = 0.01), and between lymphocytes log and RDIlog (r = 0.19; P = 0.04). Follow-up was organized after 4-6 months of treatment. Median decrease in BMI z-score was 32%. Laboratory measurements were repeated. Subjects with SDB at baseline underwent a second sleep study. Of these 49 subjects, 12 showed residual SDB. This corresponds with a treatment success rate of 71%. Unlike changes in inflammatory markers, improvements in UA were associated with improvements in RDI and ODI (respectively r = 0.44; P = 0.007, r = 0.41; P = 0.01). In conclusion, weight loss is effective in treating obese children with SDB. At baseline, a link exists between inflammation and SDB. Oxidative stress is reflected by UA at baseline and the concentration decreases after treatment according to improvements in SDB. © 2011 The Obesity Society.
Vandewalle S.,Ghent University |
Taes Y.,Ghent University |
Fiers T.,Ghent University |
Van Helvoirt M.,Zeepreventorium |
And 9 more authors.
Journal of Clinical Endocrinology and Metabolism | Year: 2014
Background: Childhood obesity is associated with an accelerated skeletal maturation. However, data concerning pubertal development and sex steroid levels in obese adolescents are scarce and contrasting. Objectives: To study sex steroids in relation to sexualandskeletal maturationandto serum prostate specific antigen (PSA), as a marker of androgen activity, in obese boys from early to late adolescence. Methods: Ninety obese boys (aged 10-19 y) at the start of a residential obesity treatment program and90 age-matched controlswerestudied cross-sectionally. Pubertal statuswasassessed according to the Tanner method. Skeletal age was determined by an x-ray of the left hand. Morning concentrations of total testosterone (TT) and estradiol (E2) were measured by liquid chromatographytandem mass spectrometry, free T (FT) was measured by equilibrium dialysis, and LH, FSH, SHBG, and PSA were measured by immunoassays. Results: Genital staging was comparable between the obese and nonobese groups, whereas skeletal bone advancement (mean, 1 y) was present in early and midadolescence in the obese males. Although both median SHBG and TT concentrations were significantly (P < .001) lower in obese subjects during mid and late puberty, median FT, LH, FSH, and PSA levels were comparable to those of controls. In contrast, serum E2 concentrations were significantly (P < .001) higher in the obese group at all pubertal stages. Conclusion: Obese boys have lower circulating SHBG and TT, but similar FT concentrations during mid and late puberty in parallel with a normal pubertal progression and serum PSA levels. Our data indicate that in obese boys, serum FT concentration is a better marker of androgen activity than TT. On the other hand, skeletal maturation and E2 were increased from the beginning of puberty, suggesting a significant contribution of hyperestrogenemia in the advancement of skeletal maturation in obese boys. Copyright © 2014 by the Endocrine Society.