Prevalence and Clinical Characteristics of Children and Adolescents with Metabolically Healthy Obesity: Role of Insulin Sensitivity

Abstract

Obesity represents a major risk factor for metabolic disorders, but some individuals, “metabolically healthy” (MHO), show less clinical evidence of these complications, in contrast to “metabolically unhealthy” (MUO) individuals. The aim of this cross-sectional study is to assess the prevalence of the MHO phenotype in a cohort of 246 overweight/obese Italian children and adolescents, and to evaluate their characteristics and the role of insulin resistance. Homeostasis model assessment–insulin resistance (HOMA-IR), insulin sensitivity index (ISI), insulinogenic index (IGI) and disposition index (DI) were all calculated from the Oral Glucose Tolerance Test (OGTT). MHO was defined by either: (1) HOMA-IR < 2.5 (MHO-IRes), or (2) absence of the criteria for metabolic syndrome (MHO-MetS). The MHO prevalence, according to MHO-MetS or MHO-IRes criteria, was 37.4% and 15.8%, respectively. ISI was the strongest predictor of the MHO phenotype, independently associated with both MHO-IRes and MHO-MetS. The MHO-MetS group was further subdivided into insulin sensitive or insulin resistant on the basis of HOMA-IR (either < or ≥ 2.5). Insulin sensitive MHO-MetS patients had a better metabolic profile compared to both insulin resistant MHO-MetS and MUO-MetS individuals. These data underscore the relevance of insulin sensitivity to identifying, among young individuals with overweight/obesity, the ones who have a more favorable metabolic phenotype.

Prevalence and clinical characteristics of metabolically healthy obese versus metabolically unhealthy obese school children

“…Although the hyperinsulinemic-euglycemic clamp is considered the gold standard for the identification of insulin resistance, due to its complexity and invasiveness, the most widespread method for assessing insulin resistance among children is through the calculation of HOMA-IR. Studies have found that children with MHO phenotype had lower HOMA-IR index as compared to children with MUO phenotype ( 13 , 29 , 31 , 37 , 38 ), however we did not observe this trend and our finding agrees with other more recent studies ( 39 , 40 ). A study found that both children with MHO and MUO phenotype had significantly higher HOMA-IR when compared to normal weight peers indicating that a state of insulin resistance was already present ( 40 ).…”

Diabetes and Obesity—Cumulative or Complementary Effects On Adipokines, Inflammation, and Insulin Resistance

“…At this moment, obesity is described as a heterogeneous syndrome (determined by the genetic and environmental factors' interaction) [8,[12][13][14]. Previous studies have pointed out the different obesity types [15]: "metabolically healthy obesity"-MHO (defined by obesity presence without metabolic disturbance or metabolic syndrome features [8,12,16] and "metabolically unhealthy obesity-MUO" [8,12,16].…”

Height-Corrected Definition of Metabolic Syndrome Is a Simple and Effective Method for Identifying Insulin Resistance and Low-Grade Inflammation in Adolescents: Metabolic Syndrome in Adolescents

“…The proportions of low-grade inflammation were similar to the adolescents with MetS defined by traditional definition. 30 These adolescents have an adverse status of insulin resistance and low-grade inflammation. So it may be suitable for considering these adolescents as MetS and giving early intervention.…”