Insulin Resistance as a Diagnostic Criterion for Metabolically Healthy Obesity in Children

Abstract

Objectives: In recent years, a subgroup of individuals with obesity has been described as having a lower risk of metabolic and cardiovascular complications. These individuals have what is referred to as metabolically healthy obesity (MHO), which has a favorable metabolic profile and a lower probability of longterm complications. The definition of this subtype in children is not clear. The aim of the present study was to determine whether Homeostasis Model Assessment (HOMA) above a set threshold could be the marker of metabolically unhealthy obesity (MUO) in children, or a parameter that can be used in the overall assessment. It is intended to compare the International Diabetes Federation (IDF) criteria against HOMA in the diagnosis of MUO. Methods: This observational, retrospective, cohort study included children with obesity and analyzed their metabolic state by means of blood testing and dual-energy X-ray absorptiometry. Results: A total of 96 patients were included, 44.8% boys and 55.2% girls, ages 6-17 years. The patients with MHO according to the HOMA criterion were younger (P ¼ 0.001), had a lower body mass index (BMI) z score (P ¼ 0.006), waist-height index (P ¼ 0.009), hip-height index (P ¼ 0.010), blood glucose (P ¼ 0.003), insulin (P < 0.001), and lower percentages of total fat (P ¼ 0.002), trunk fat (P ¼ 0.001), and android fat (P ¼ 0.009) than those with MUO. The logistic regression analysis according to IDF criteria detected an area under the receiver operating characteristic (ROC) curve of 0.659 (95% CI 0.546-0.771; P ¼ 0.009) versus the area under the ROC curve of 0.854 (95% CI 0.777-0.931; P < 0.001) for the HOMA definition. Therefore, the determination of the metabolic state according to HOMA has greater sensitivity and specificity than the IDF criteria. The multivariate analysis in children classified according to HOMA revealed that the percentage of total fat and gynoid fat distributions and triglyceride level could be markers of a healthy or unhealthy metabolic state in children with obesity (P < 0.001). Conclusions: The use of HOMA as a single criterion was demonstrated to be an effective and simple detector of adiposity, which predicts the metabolically healthy obesity in children.

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 ).…”

Mechanisms and risk factors of metabolic syndrome in children and adolescents

“…An MHO phenotype during childhood is more likely to be retained during adulthood [ 86 , 87 ]. Furthermore, the conversion of MHO children to MUO is determined by the loss of insulin sensitivity [ 88 , 89 ], thus corroborating the hypothesis that MetS begins with obesity but requires IR to develop [ 90 ]. It is important to note that a physiological and transient IR occurs during pubertal development, and it could accelerate the onset of MetS in a pre-existing state of obesity-dependent IR [ 16 , 35 ].…”

Degree of Accuracy of the BMI Z-Score to Determine Excess Fat Mass Using DXA in Children and Adolescents

“…Given the increase in childhood obesity and its associated complications in adulthood, early detection is of great importance for early intervention, which is why it is important to use precise diagnostic criteria agreed upon by scientific societies [21][22][23]. This is especially true when the presence of symptoms associated with the metabolic syndrome begin to be present during childhood in a significant number of children with obesity [4].…”

“…Childhood obesity, defined as an excessive accumulation of energy in the form of fat in the pediatric population, is associated with a wide range of serious health complications and an increased risk of early onset of diseases such as diabetes, dyslipidemia, and cardiovascular disease, among others [1,3,4].…”