Low Grade Inflammation in Childhood Obesity : an Independent Risk Factor for Endothelial Dysfunction
Phase: NA
Conditions: Obesity, Childhood, Obesity, Endothelial Dysfunction, Cardiovascular Risk Factor, Inflammation
Sponsor: Universitair Ziekenhuis Brussel

 
 
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Protocol Clinical Trial 
 
 
Study synopsis 
 
 
 
 
Study overview 
Title of clinical trial 
 
Sponsor name 
University Hospital of Brussels 
Principal Investigator 
prof. dr. Jean De Schepper / Inge Gies 
Medical condition or 
disease under 
investigation 
Obesity and overweight, cardiovascular risk factors 
Purpose of clinical trial 
To assess whether low grade inflammation in childhood obesity 
contributes to endothelial dysfunction  
Primary objective 
To investigate if the reactive hyperemia index by peripheral 
arterial tonometry is higher in adolescents with a history of 
childhood obesity and presenting a low grade inflammation in 
comparison with those without low grade inflammation ( hSCRP 
< or > 1 mg/L)  
Secondary objective (s) 
To analyze the changes in hCRP and adiposity in obese children 
and adolescents after 5 to 10 years  
Trial Design 
Observational cohort study 
Endpoints 
RH-PAT scores, measured by peripheral artery tonometry . 
hSCRP, measured by automated immunoturbidometry 
BMI z-score and % body fat by skinfold thichness  
Sample Size 
54  (α= 0,05 – power 80%) 
Summary of eligibility 
criteria 
Overweight and obese adolescents, aged 12 to 21 years, with a 
known level of hs-CRP at initial evaluation for metabolic 
syndrome  
Maximum duration of 
intervention 
Single visit 
Version and date of 
final protocol 
Protocol version 1, date 18/08/2018 
Version and date of 
protocol amendments 
Not applicable 

 
 
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Study Schedule 
 
 Administrative information  
1. Sponsor 
The study is sponsored by the division of pediatric endocrinology of the  University Hospital 
of Brussels ( UZ Brussel).  
 
2. (Principal) Investigator(s) 
 
 
Prof. dr. J. De Schepper 
Dr. K. Stabenow 
Prof. Dr. Inge Gies 
Dr. Karolien Van De Maele 
Dr. Jesse Vanbesien  
 
3. Departments involved 
 
Department of Pediatrics 
Division of Pediatric Endocrinology 
University Hospital of Brussels 
Laarbeeklaan 101, 1090 Brussel 
 
 
 
Ethical and regulatory information  
1. Study registration 
The study is registered at ClinicalTrials.gov and has a unique number: ###. 
 
2. Study type 
The study is an observational cohort study  
 
3. Competent Ethics Committee 
 
Central Ethics Committee:  
Ethical Committee University Hospital of Brussels 
Phone: 32 2 474 94 15 
Email: Centraal_Studieloket@uzbrussel.be 
 
 
4. Ethical conduct of the study 
The trial will be conducted in compliance with the principles of the Declaration of Helsinki 
(current version), the principles of Good Clinical Practice (GCP) and in accordance with all 

 
 
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applicable regulatory requirements. This protocol and related documents will be submitted 
for review to Ethics Committee before start of the trial. 
 
5. Declaration of conflict of interest 
The investigators of this study declare that they don’t have any competing interests. 
 
 
6. Patient information and informed consent 
The study will be conducted only after obtaining a prior informed consent of the legal 
representatives of the children and obtaining an assent of the children according to their age 
and maturity. The legal representatives of the children will sign an informed consent form 
and the assent of the children will be noted in the corresponding file. The informed consent 
form and the assent will be reviewed by the Ethics Committee prior to the start of 
recruitment. 
 
7. Participant privacy and confidentiality 
The investigators shall treat all information and data relating to the study disclosed to 
Participating Site and/or Investigator in this Study as confidential and shall not disclose such 
information to any third parties or use such information for any purpose other than the 
performance of the study. The collection, processing and disclosure of personal data, such as 
patient health and medical information is subject to compliance with applicable personal data 
protection and the processing of personal data (Directive 95/46/EC and Belgian law of 
December 8, 1992 on the Protection of the Privacy in relation to the Processing of Personal 
Data) as well as the General Data Protection of April 2018.  
The data will be coded. There continues to be a link between the data and the individual 
who provided it. The research team is obligated to protect the data from disclosure outside 
the research according to the terms of the research protocol and the informed consent 
document. The subject’s name or other identifiers are stored separately from their research 
data and replaced with a unique code to create a new identity for the subject. 
 
8. Early termination of the study 
Not applicable. 
 
9. Protocol amendments 
Changes to the study protocol will be submitted to the Ethics Committee and will not be 
performed before obtaining an approval. 
 
10. Reward  
Participant will not receive a compensation for their participation in the study. If needed, an 
absence certificate will be provided for the participant and/or the accompanying adult at the 
time of the study visit. 
 
Background and rationale 
Obesity and overweight have become an important health burden in children and adolescents, with 
19% of all children between 5 and 18 years being either obese or overweight in Belgium(1,2). Obesity 
and especially visceral adiposity early in life may contribute to the development of cardiovascular 
disease at older age, as it shows tracking into adulthood and is be associated with cardiovascular risk 

 
 
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factors such as dyslipidemia, insulin resistance, arterial hypertension and low grade inflammation, in 
a variable percentage (4) (5)  
Low grade inflammation, as assessed by hSCRP, was found to be present in 20.6 % and 19.8 % of 
overweight children and adolescents (6). In adults, hSCRP levels between 1 and 3 mg/L and above 3 
mg/L are considered coronary disease risk factors (7). 
Endothelial dysfunction, know to precede the formation of atherosclerotic plaque, can be assessed in 
a non-invasive manner in children by peripheral artery tonometry. (8)  Only few studies have been 
performed in obese children with this bed-side technique, showing either normal of a disturbed 
function, reflected by a lower reactive hyperemia index (9, 10,11) The association with low grade 
inflammation however was assessed in only one study.  We hypothesize that in adolescents and 
young adults with a history of childhood obesity a more disturbed endothelial function will be 
present in those with and /or current elevated hSCRP value.  
Study Objectives 
To investigate whether obese and overweight adolescents with an elevated hs-CRP are more 
at risk for the development of endothelial dysfunction assessed peripheral artery tonometry, 
compared to those with a normal hs-CRP at their initial evaluation for obesity-associated metabolic 
syndrome  
 
To assess the degree of endothelial dysfunction, assessed by the reactive hyperemia index 
by peripheral artery tonometry in adolescents and young adults with a history of childhood 
obesity in relation to the their current hS CRP value 
 
To investigate the changes in hs-CRP and adiposity in adolescence and young adulthood of 
initially obese children and adolescents with either normal or elevated hs-CRP levels  
 
Study outcomes 
1. Primary outcome 
Reactive hyperemia index (RHI) measured by the EndoPAT device  
2. Secondary outcome 
hS CRP value , BMI z-score and body fat percentage assessed by skinfold thickness  
 
Study design 
1. Overall design 
This is an observational cohort study  
 
2. Randomization/blinding procedure. 
Not applicable. 
 
3. Statistical methodology 
 
The statistical analysis will be done with the SPSS software.  
The difference in THI index between the population with and without low grade inflammation  
will be evaluated by the Mann Whitney U test and Multivariate analysis of variance, taking 
current hCRP, age, BMI z-score, and systolic blood pressure into account. The change in hS 

 
 
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CRP in the population with and without low grade inflammation will be analyzed by the 
Kruskall Wallace test.  
 
The power calculation was done at clincalc.com/stats/samplesize software. Assuming a mean 
RHI score of 1.51 in overweight children with a standard deviation of 0.2 (9), assuming an 
equal distribution between the study groups (elevated vs. normal hs-CRP), we have a power 
of 0.80 to demonstrate a difference of 20 % between the two groups with 27 patients enrolled 
in each group.  
 
 
Study population 
1. Recruitment 
Eligible candidates will be recruited within the children with overweight and obesity having a 
metabolic risk evaluation before treatment in the period 2006 and 2010 at the pediatric 
clinic of the UZ Brussel  In total 60 participants will be investigated. Firstly, 30 participating 
patients with initially elevated hsCRP will be selected at random ( following the date of their 
initial investigation) and afterwards matched for age, BMI z-score, and blood pressure with 
the same number of patients without initially elevated hCRP values  
 
2. Recruitment procedure 
Eligible candidates, or their parents if underage, will be personally contacted by telephone 
and/or e-mail  by their initial pediatric endocrinologist and  will be invited to partake in the 
study. All written information about the study will be provided beforehand.  
 
3. Eligibility criteria 
 Inclusion Criteria:  
o Age 12-21 years at the moment of evaluation   
o BMI > 1.3 SDS at the  initial evaluation  
o Hs-CRP available at initial evaluation  
 Exclusion Criteria 
o Acute of chronic Infection at the time of the study visit  
Be or have been a smoker of tabacco    
 
 
 

 
 
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Study intervention 
1. Study overview 
A single visit is planned. During this visit a standard questionnaire on current health status,  
life style will be filled in a selfscore of pubertal development using standardized pictures will 
be done. Standard anthropometrics and blood-pressure measurements , a blooddrawn for 
hSCRP and a peripheral artery tonometry will be performed.  
 
 
2. Identification of intervention 
 
 Anthropometry: 
Anthropometric measurement sites are defined according to the international standards. (10) 
 
- 
Weight will be measured using a calibrated digital scale (SECA, Hamburg, Germany) 
and will be rounded up to the nearest 0,05 kg. Participants will be wearing light 
clothing (underwear). 
- 
 
Standing height will be measured using a stadiometer with a movable headboard and 
vertical backboard and will be rounded up to the nearest 0,1 cm. 
 
- 
Waist circumference will be measured in the middle of the lowest rib (10th rib) and 
the iliac crest at the end of a normal expiration. The girths will be measured with a 
flexible Lufkin steel anthropometric tape (Lufkin W606PM).  
 
- 
Tricipital and subscapular skinfold thickness will be measured by a Harpenden caliper 
using the Slaughter guidelines.  
 
- 
The BMI z-score will be calculated using the Vlaamse groeistudie 2004 references  
 
- 
The Slaughter formula will be used to calculate the body fat percentage.  
 
 
 Blood pressure (mean of 3 measurements) 
Blood pressure will be measured using an oscillometric, electronic device (Mindray). The blood 
pressure will be measured 3 times; the first measurement will not be taken into account and 
the mean of the second and third measurement will be calculated.  
 
 Peripheral arterial tonometry 
The pulse wave amplitude will be measured by a commercial finger plethysmograph 
EndoPAT, Itamar Medical Ltd, Caesarea, Isreal.)  
 
Briefly explained, both index fingers of the patient are placed in the pneumatic probes. First 
the device performs 5 minutes of baseline measurement and thereafter a blood pressure 
cuff occludes the arterial flow of the arm for 5 minutes. After a rapid deflation of the cuff a 

 
 
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reactive hyperemia takes place which is a measure for the arterial endothelial function. 
There is a concomitant software package which calculates the Reactive Hyperemia Index 
(RHI) and peak dilatation.  
 
Participants will be asked not to engage in strenuous sport activities the 24 hours preceding 
the test. (12)   
 
                    hS-CRP  
 
Will be measured at the Chemical Chemistry Laboratory of the UZ Brussel using by 
immunoturbimety by the Vitros 4600 / Ortho Clinical Diagnostics analyzer.  
 
 
Safety  
1. Insurance  
All damage or injuries resulting from the study participation will be covered by the no fault 
insurance available at Ethias through the University Hospital of Brussels.  
 
2. Anticipated possible adverse events 
The peripheral arterial tonometry can cause a tingling feeling in the occluded arm that will 
disappear after deflation of the cuff. 
Drawing blood may lead to discomfort, pain or a hematoma at the puncture site and syncope. 
 
Quality assurance 
EndoPAT device measurements will be done by the same person after training by the  
technicians.  Calibrated instrumented will be used and blood will be drawn according to 
standard procedures in the University Hospital of Brussel (UZ Brussel). The CRP analysis has a 
CV of 4.8 % for 1.03 mg/L value.  
 
Privacy policy   
The medical file data will be collected after agreement of the responsible treating paediatric 
endocrinologist. The questionnaire data and medical file data will be merged into an Excel 
document, which will be protected by a password. All the obtained data will be handled in a 
confidential way. All names, birth dates and residence data will be erased from the final 
datafile, which will be stored on a protected server of the UZ Brussel by Prof dr Jean De 
Schepper, who is the responsible for the data collection and storage. Collected data will be 
stored for 5 years. The Data Protection Officer of the UZ Brussel ( Audrey Van Scharen 
(dpo@vub.be ) is  responsible for further information on data protection. Participants will be 
informed about the DPO and their right to correct of withdraw collected data. 
 
Publication policy 
All publication rights of unprocessed and processed data belong to the investigators.  
 
 
 
 

 
 
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national prevalence of overweight and obesity in children and adults during 1980-2013: a 
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81. 
2.Wetenschappelijk Instituut Volksgezondheid. Gezondheidsenquête 2013. 
3. Ogden CL, Carroll MD, Kit BK, Flegal KM.Prevelance of childhood and adult obesity in the 
United States. JAMA. 2014; 311(8):806-14. 
4.Park MK. Park's pediatric cardiology – sixth edition. Philadelphia: Elsevier Saunders; 2014. 
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5. Franks PW et. Al. Childhood obesity, other cardiovascular risk factors and premature death. 
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7. Pearson TA et al. Markers of inflammation and cardiovascular disease: application to clinical 
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499-51 
8. Skrzypyck P, Panczyk-Tomaszewska M. Methods to evaluate arterial structure and function 
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9.Pareyn A, Allegaert K, Verhamme P, VInckx J, Casteels K. Impaired endothelial function in 
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10. Tryggestad JB, Thompson DM, Copeland KC, Short KR. Obese children have higher arterial 
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20: 165-171.  
11. Tomsa A et al. Endothelial function in youth. A biomarker modulated by adiposity-related 
insulin resistance. Pediatric: 178: 171-177..  
12.Bruyndonckx L, Radtke T, Eser P, Vrints CJ, Ramet J, Wilhelm M, et al. Methodological 
considerations and practical recommendations for the application of peripheral arterial 
tonometry in children and adolescents. Int J Cardiol. 2013;168(4):3183-90.