**Author details**

cents, although slightly higher than references from Lopez-Capapé (18%) [25], Tapia (18.6%) [27] and Olza (16.8%) [28] in Spanish obese pediatric population. Nevertheless, the contrast of the rate of prevalence from different studies has a relative value, since the criteria applied are different, and even different cut points for each component of metabolic syndrome are used

This study follows Cook modified criteria (abdominal perimeter has been replaced by BMI in the assessment of obesity, and fasting plasma glucose higher than 110 mg/dl has been replaced by HOMA index higher than 3.8). These criteria have gradually acquired clinical relevance in the assessment of metabolic syndrome in pediatric age and support from the scientific community [12, 25, 27, 28, 31]; this allows, on one side, the achievement of comparisons among the results of the different national and international studies and, on the other side, justifies its

The IDF considers fat distribution and, concretely, central or visceral obesity—which is defined by abdominal perimeter—as a "sine qua non" criterion for the diagnosis of metabolic syndrome due to its high predictive value for cardiovascular disease in adult life [36, 37]. However, there is some controversy regarding the adequacy of its use as a main and/or necessary diagnostic criterion [38]; in fact, recent studies conducted in pediatric population have used both abdominal perimeter [12, 13, 15, 39] and BMI [14, 16, 18, 25] interchangeably. In this case, the inclusion criterion was BMI value (*Z*-score) higher than +2.0 (97th percentile) by age and sex according to the growing charts from Ferrández et al. (Centro Andrea Prader, Zaragoza

Insulin resistance, as several authors have highlighted [16, 25], has been a very frequently noted metabolic disorder in the population studied. It is worth indicating that, when Reaven [40] described the syndrome X, he considered insulin resistance as the determining pathophysiological factor and, in fact, the WHO included it as main and necessary criterion in order to diagnose the metabolic syndrome [20]. However, the diagnosed criteria subsequently proposed by the National Cholesterol Education Programs Adult Treatment Program III [21] and the IDF [23] opted for a "lipid centric" theory, with special focus on dyslipidemia and/or fat

Even though several criteria have been used to evaluate peripheral insulin sensitivity and/or alterations in glucose metabolism (fasting glucose, glycemia after an oral glucose tolerance test (OGTT), fasting insulin levels, etc.), the use of a mathematical model called *homeostasis model assessment* (HOMA) as a criterion for insulin resistance has been widely contrasted as an early disorder in glucose homeostasis (hyperinsulinemia with euglycemia). In this case, despite the application of a quite restrictive cut point [21], insulin resistance was already detected in 39% of the patients included in the study. In addition, the existing correlation between the HOMA indexes and the age of the patients at the moment of examination suggests that the onset of this metabolic comorbidity associated with obesity is related to hormonal changes concomitant

The situation of insulin resistance usually involves a disturbance in lipid profile by stimulating lipolysis and, therefore, an increase in plasma exchange of fatty acids that, at the same time,

[26, 28].

2002) [33].

distribution.

use as reference diagnosis criteria in this work.

158 Adiposity - Epidemiology and Treatment Modalities

with puberty rather than to the evolution time of obesity.

Teodoro Durá-Travé1,2,3\*, Fidel Gallinas-Victoriano2 , Leyre Lloreda-Martín1 , Alberto Ríos-Muñoz2 , Inés Niyubahwe2 and Ander Ernaga-Lorea2

\*Address all correspondence to: tduratra@cfnavarra.es

1 Department of Pediatrics, School of Medicine, University of Navarra, Pamplona, Spain

2 Department of Pediatrics, Navarra Hospital Complex, Pamplona, Spain

3 Navarra Institute for Health Research (IdisNa), Pamplona, Spain
