title: Childhood obesity classification systems and cardiometabolic risk factors: a comparison of the Italian, World Health Organization and International Obesity Task Force references.
abstract: BACKGROUND
  Body Mass Index Italian reference data are available for clinical and/or epidemiological use, but no study compared the ability of this system to classify overweight and obesity and detect subjects with clustered cardiometabolic risk factors with international standards. Therefore our aim was to assess 1) the agreement among the Italian Society for Pediatric Endocrinology and Diabetology (ISPED), the World Health Organisation (WHO) and the International Obesity Task Force (IOTF) Body Mass Index cut-offs in estimating overweight or obesity in children and adolescents; 2) the ability of each above-mentioned set of cut-points to detect subjects with cardiometabolic risk factors.
  
  
  METHODS
  Data of 6070 Italian subjects aged 5-17 years were collected. Prevalence of normal-weight, overweight and obesity was determined using three classification systems: ISPED, WHO and IOTF. High blood pressure, hypertriglyceridemia, low high density lipoprotein-cholesterol and impaired fasting glucose were considered as cardiometabolic risk factors.
  
  
  RESULTS
  ISPED and IOTF classified more subjects as normal-weight or overweight and less subjects as obese as compared to WHO (p <0.0001) in the whole sample and in groups divided by gender and age. The strength of agreement between the three methods compared to each other was excellent for overweight (including obesity) definition (k > 0.900), while it differed for obesity definition, ranging from the highest agreement between ISPED and IOTF (k 0.875) to the lowest between ISPED and WHO (k 0.664). WHO had the highest sensitivity, while ISPED and IOTF systems had the highest specificity, in identifying obese subjects with clustered cardiometabolic risk factors. Analogous results were found in subjects stratified by gender or age.
  
  
  CONCLUSIONS
  ISPED and IOTF systems performed similarly in assessing overweight and obesity, and were more specific in identifying obese children/adolescents with clustered cardiometabolic risk factors; on the contrary, the WHO system was more sensitive. Given the seriousness of the obesity epidemic, we wonder whether the WHO system should be preferable to the national standards for clinical practice and/or obesity screening.
authors.affiliation: Department of Movement Sciences and Wellbeing, Parthenope University, Naples, Italy. giuliana.valerio@uniparthenope.it.
authors.forename: Giuliana
authors.identifier: http://orcid.org/0000-0001-5063-4333
authors.initials: G
authors.lastname: Valerio
authors.affiliation: Department of Medical and Surgical Sciences, Pediatric Unit, Azienda Ospedaliero-Universitaria S.Orsola-Malpighi, Bologna, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Balsamo
authors.affiliation: Department of Experimental Medicine, Sapienza University of Roma, Rome, Italy.|Endocrinology and Diabetes, Department of Medical Sciences, University of Cagliari, Cagliari, Italy.
authors.forename: Marco Giorgio
authors.initials: MG
authors.lastname: Baroni
authors.affiliation: Endocrinology and Diabetes Unit, Bambino Gesù Children's Hospital, Rome, Italy.|Azienda Unità Sanitaria Locale di Viterbo, Viterbo, Italy.
authors.forename: Claudia
authors.initials: C
authors.lastname: Brufani
authors.affiliation: Department of Pediatrics, Santa Maria delle Grazie Hospital, Pozzuoli, Napoli, Italy.
authors.forename: Claudia
authors.initials: C
authors.lastname: Forziato
authors.affiliation: Division of Auxology, Italian Auxological Institute, Verbania, Italy.
authors.forename: Graziano
authors.initials: G
authors.lastname: Grugni
authors.affiliation: Department of Pediatrics, AORN Santobono-Pausilipon, Naples, Italy.
authors.forename: Maria Rosaria
authors.initials: MR
authors.lastname: Licenziati
authors.affiliation: Pediatric Diabetes & Metabolic Disorders Unit, Department of Surgical Sciences, Dentistry, Gynecology and Pediatrics, University of Verona, Verona, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Maffeis
authors.affiliation: Department of Woman, Child and General and Specialized Surgery, University of Campania "Luigi Vanvitelli", Napoli, Italy.
authors.forename: Emanuele
authors.initials: E
authors.lastname: Miraglia Del Giudice
authors.affiliation: Pediatric Diabetes & Metabolic Disorders Unit, Department of Life & Reproduction Sciences, University Hospital of Verona, Verona, Italy.
authors.forename: Anita
authors.initials: A
authors.lastname: Morandi
authors.affiliation: Department of Pediatrics and Child Neuropsychiatry, Sapienza University of Rome, Rome, Italy.
authors.forename: Lucia
authors.initials: L
authors.lastname: Pacifico
authors.affiliation: Department of Pediatrics, Santa Maria delle Grazie Hospital, Pozzuoli, Napoli, Italy.|Division of Auxology, Italian Auxological Institute, Milan, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Sartorio
authors.affiliation: Research Unit for Multifactorial Diseases, Scientific Directorate, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy.
authors.forename: Melania
authors.initials: M
authors.lastname: Manco
mesh_terms: D000293:Adolescent; D026683:Advisory Committees; D001786:Blood Glucose; D015992:Body Mass Index; D002648:Child; D002675:Child, Preschool; D008078:Cholesterol, LDL / Q000097:blood; D032921:Consensus; D005260:Female; D006801:Humans; D006973:Hypertension; D007558:Italy / Q000453:epidemiology; D008297:Male; D050177:Overweight / Q000145:classification / Q000175:diagnosis; D063766:Pediatric Obesity / Q000145:classification* / Q000175:diagnosis* / Q000453:epidemiology; D015995:Prevalence; D012016:Reference Values; D012307:Risk Factors; D012955:Societies, Medical; D014280:Triglycerides / Q000097:blood; D014944:World Health Organization
chemical_list: D001786:Blood Glucose; D008078:Cholesterol, LDL; D014280:Triglycerides
keywords: Adolescents; Body mass index; Cardiometabolic risk factors; Children; Classification; Cut-offs; Obesity; Overweight