title: Association of myeloperoxidase levels with cardiometabolic factors and renal function in prepubertal children.
abstract: BACKGROUND
  Myeloperoxidase (MPO), an enzyme linking obesity and cardiovascular (CV) risk in adults, has rarely been studied in young children and no studies assessed its association with renal function. We sought to explore a possible association between serum MPO levels, obesity, CV risk factors and renal function in prepubertal children.
  
  
  METHODS
  Cross-sectional evaluation of 309 children aged 8-9 years (161 normal weight, 148 overweight/obese), members of the birth cohort Generation I (Portugal). Anthropometrics (body mass index (BMI), waist-to-height ratio (WHtR) and % body fat mass (%BFM) by bioelectrical impedance analysis), 24-h ambulatory blood pressure monitoring and pulse wave velocity (PWV) were measured. Insulin resistance was estimated by the HOMA index (considering serum fasting glucose and insulin determinations). Serum MPO levels were assessed by immunoenzymatic assay.
  
  
  RESULTS
  MPO levels were positively associated with obesity indices (BMI z-score, WHtR and %BFM). Higher MPO levels were associated with higher 24-h and night-time mean arterial pressure, with nondipping and with higher values of insulin resistance. In normal weight children, the endothelial function, as evaluated indirectly by PWV, was an independent predictor of MPO levels. In overweight/obese children, estimated glomerular filtration rate increased significantly across tertiles of MPO (Ptrend = 0·031) and this association held after adjustment for age, sex, neutrophil and monocyte counts and CV risk factors.
  
  
  CONCLUSIONS
  Our results reinforce the role of MPO as a risk marker in obesity and related CV morbidities in young children. MPO levels associate with the dipping pattern and PWV and, among overweight/obese children, an association exists between MPO and renal function.
authors.affiliation: EPIUnit - Institute of Public Health, University of Porto, Porto, Portugal.|Division of Pediatric Nephrology, Integrated Pediatric Hospital, Centro Hospitalar São João, Porto, Portugal.
authors.forename: Liane
authors.initials: L
authors.lastname: Correia-Costa
authors.affiliation: Department of Pharmacology and Therapeutics, Faculty of Medicine of University of Porto, Porto, Portugal.|MedInUP - Center for Drug Discovery and Innovative Medicines, University of Porto, Porto, Portugal.
authors.forename: Teresa
authors.initials: T
authors.lastname: Sousa
authors.affiliation: Department of Pharmacology and Therapeutics, Faculty of Medicine of University of Porto, Porto, Portugal.|MedInUP - Center for Drug Discovery and Innovative Medicines, University of Porto, Porto, Portugal.|Laboratory of Pharmacology, Department of Drug Sciences, Faculty of Pharmacy of Porto, REQUIMTE, University of Porto, Porto, Portugal.
authors.forename: Manuela
authors.initials: M
authors.lastname: Morato
authors.affiliation: EPIUnit - Institute of Public Health, University of Porto, Porto, Portugal.|Department of Pharmacology and Therapeutics, Faculty of Medicine of University of Porto, Porto, Portugal.
authors.forename: Dina
authors.initials: D
authors.lastname: Cosme
authors.affiliation: Department of Pharmacology and Therapeutics, Faculty of Medicine of University of Porto, Porto, Portugal.
authors.forename: Joana
authors.initials: J
authors.lastname: Afonso
authors.affiliation: Division of Pediatric Cardiology, Integrated Pediatric Hospital, Centro Hospitalar São João, Porto, Portugal.
authors.forename: Cláudia
authors.initials: C
authors.lastname: Moura
authors.affiliation: Division of Pediatric Cardiology, Integrated Pediatric Hospital, Centro Hospitalar São João, Porto, Portugal.
authors.forename: Cláudia
authors.initials: C
authors.lastname: Mota
authors.affiliation: Division of Pediatric Cardiology, Integrated Pediatric Hospital, Centro Hospitalar São João, Porto, Portugal.
authors.forename: José Carlos
authors.initials: JC
authors.lastname: Areias
authors.affiliation: Division of Pediatric Nutrition, Integrated Pediatric Hospital, Centro Hospitalar São João, Porto, Portugal.
authors.forename: António
authors.initials: A
authors.lastname: Guerra
authors.affiliation: Division of Pediatric Nephrology, Center for Pediatrics and Adolescent Medicine, University of Heidelberg, Heidelberg, Germany.
authors.forename: Franz
authors.initials: F
authors.lastname: Schaefer
authors.affiliation: EPIUnit - Institute of Public Health, University of Porto, Porto, Portugal.|Division of Pediatric Nephrology, Integrated Pediatric Hospital, Centro Hospitalar São João, Porto, Portugal.
authors.forename: Alberto
authors.initials: A
authors.lastname: Caldas Afonso
authors.affiliation: EPIUnit - Institute of Public Health, University of Porto, Porto, Portugal.|Department of Clinical Epidemiology, Predictive Medicine and Public Health, Faculty of Medicine of University of Porto, Porto, Portugal.
authors.forename: Henrique
authors.initials: H
authors.lastname: Barros
authors.affiliation: Department of Pharmacology and Therapeutics, Faculty of Medicine of University of Porto, Porto, Portugal.|MedInUP - Center for Drug Discovery and Innovative Medicines, University of Porto, Porto, Portugal.
authors.forename: António
authors.initials: A
authors.lastname: Albino-Teixeira
authors.affiliation: EPIUnit - Institute of Public Health, University of Porto, Porto, Portugal.|Department of Clinical Epidemiology, Predictive Medicine and Public Health, Faculty of Medicine of University of Porto, Porto, Portugal.
authors.forename: Ana
authors.initials: A
authors.lastname: Azevedo
mesh_terms: D000273:Adipose Tissue; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure; D018660:Blood Pressure Monitoring, Ambulatory; D001823:Body Composition; D002318:Cardiovascular Diseases / Q000097:blood* / Q000453:epidemiology; D002648:Child; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D017097:Electric Impedance; D004730:Endothelium, Vascular; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D008297:Male; D009765:Obesity / Q000097:blood* / Q000453:epidemiology; D050177:Overweight / Q000097:blood / Q000453:epidemiology; D009195:Peroxidase / Q000097:blood*; D011174:Portugal / Q000453:epidemiology; D063177:Pulse Wave Analysis; D012307:Risk Factors
chemical_list: D001786:Blood Glucose; D007328:Insulin; D009195:Peroxidase
keywords: Blood pressure; childhood obesity; glomerular filtration rate; myeloperoxidase; pulse wave velocity