RESUMO
BACKGROUND: Studies on adults have reported inverse association between the homeostatic model assessment (HOMA) of adiponectin (HOMA-Adiponectin) and the insulin resistance assessed by the glucose clamp technique. To our knowledge, in the pediatric population this association has not been previously investigated. OBJECTIVES: To evaluate the association between the HOMA-Adiponectin and the insulin resistance assessed by the glucose clamp technique in adolescents, and to compare the accuracy of HOMA-Adiponectin and HOMA-insulin resistance (HOMA-IR) for identifying insulin resistance. METHODS: This was a cross-sectional study of 56 adolescents (aged 10-18 years). Insulin resistance was assessed using the HOMA-IR, HOMA-Adiponectin and the hyperglycaemic clamp technique. The clamp-derived insulin sensitivity index, HOMA-Adiponectin, and HOMA-IR were log-transformed to get closer to a normal distribution before analysis. RESULTS: In the multivariable linear regression analysis controlling for sex and Tanner stage, HOMA-Adiponectin was inversely associated with the clamp-derived insulin sensitivity index (unstandardized coefficient [B] = -0.441; P < 0.001). After additional adjustment for waist circumference-to-height ratio, this association remained significant (B = -0.349; P = < 0.001). Similar results were observed when HOMA-IR replaced HOMA-Adiponectin in the model (B = -1.049 and B = -0.968 after additional adjustment for waist circumference-to-height ratio); all P < 0.001. The area under the receiver operating characteristic curve for predicting insulin resistance was 0.712 (P = 0.02) for HOMA-Adiponectin and 0.859 (P < 0.0001) HOMA-IR. CONCLUSIONS: The HOMA-Adiponectin was independently associated with insulin resistance and exhibited a good discriminatory power for predicting it. However, it did not show superiority over HOMA-IR in the diagnostic accuracy.
Assuntos
Adiponectina/sangue , Homeostase , Resistência à Insulina , Modelos Biológicos , Adolescente , Criança , Estudos Transversais , Feminino , Técnica Clamp de Glucose , Humanos , MasculinoRESUMO
OBJECTIVE: To evaluate the association of the sagittal abdominal diameter (SAD) with insulin resistance (IR) and metabolic syndrome (MetS) components, and to compare SAD with waist circumference (WC). SUBJECTS/METHODS: This was a multicenter, cross-sectional study of 520 adolescents (10- to 18-years old). IR was assessed using the homeostasis model assessment of IR (HOMA-IR) and the hyperglycaemic clamp (n = 76). RESULTS: SAD and WC were positively correlated with HOMA-IR (r = 0.637 and r = 0.653) and inversely correlated with the clamp-derived insulin sensitivity index (ISI) (r = -0.734 and r = -0.731); P < .001. In the multivariable linear regression analysis, SAD was positively associated with HOMA-IR (B = 0.046 ± 0.003) and inversely associated with the clamp-derived ISI (B = -0.084 ± 0.009) after adjusting for sex, age, and Tanner's stages (P < .001). When WC replaced the SAD, it was positively associated with HOMA-IR (B = 0.011 ± 0.001) and inversely associated with the clamp-derived ISI (B = -0.018 ± 0.002); P < .001. The values of the areas under the curves (AUC) were 0.823 and 0.813 for SAD and WC, respectively. In Bland-Altman analysis, there were agreement between both, SAD and WC, with the clamp-derived ISI (mean = 0.00; P > .05). The SAD and WC were positively associated with blood pressure, triglycerides, and uric acid, and inversely associated with high-density lipoprotein (HDL)-cholesterol after adjusting for sex, age, and Tanner's stages. CONCLUSION: The SAD was associated with IR and MetS components, with a good discriminatory power for detecting IR. When compared to WC, SAD showed equivalent results.
Assuntos
Resistência à Insulina , Síndrome Metabólica/fisiopatologia , Diâmetro Abdominal Sagital , Gordura Abdominal , Adolescente , Brasil , Criança , Estudos Transversais , Feminino , Técnica Clamp de Glucose , Humanos , Masculino , Circunferência da CinturaRESUMO
OBJECTIVE: This study aimed to identify cutoff points for detecting hypertriglyceridemic waist phenotype (HTWP) in adolescents and to investigate the association of the HTWP with insulin resistance (IR) and metabolic syndrome components. METHODS: A multicentric cross-sectional study of 861 adolescents (10-19 years of age, 504 girls) was conducted. Pubertal stage, anthropometric, and laboratory parameters were assessed. IR was assessed by Homeostasis Model Assessment for Insulin Resistance (HOMA1-IR) index and hyperglycemic clamp (n = 80). HTWP was defined by the presence of increased plasma triglycerides (TGs) and increased waist circumference (WC) according to cutoff points obtained in ROC curve analysis given the HOMA1-IR index as a reference method. RESULTS: Cutoffs for WC and TGs, with a higher sum of sensitivity (S) and specificity (E), were, respectively: >84 cm (S:65.1%, E:71.9%) and >87 mg/dL (S:65.1%, E:73.4%) in pubertal girls; >88.5 cm (S:80.2%, E:60.2%) and >78 mg/dL (S:60.5%, E:53.2%) in postpubertal girls; >94 cm (S:73.1%, E:83.1%) and >79 mg/dL (S:61.5%, E:60.2%) in pubertal boys; and >99 cm (S:81.3%, E:78.7%) and >86 mg/dL in postpubertal boys (S:68.1%, E:60.7%). HTWP frequency was 27.5%. In the phenotype presence, after adjustment for age and pubertal stage, blood pressure and fasting glucose levels were elevated and high-density lipoprotein cholesterol was lower (p < 0.001). Adolescents with the HTWP showed more IR, evaluated both by the HOMA1-IR and by the clamp test (p < 0.003). CONCLUSION: The findings suggest HTWP as an IR status in adolescents. Cutoff point standardization for gender and pubertal stage, combined with the ease of application of the method, may allow their use for screening adolescents who would most benefit from lifestyle changes.
Assuntos
Cintura Hipertrigliceridêmica , Resistência à Insulina/fisiologia , Adolescente , Pressão Sanguínea , Brasil/epidemiologia , Criança , Estudos Transversais , Feminino , Teste de Tolerância a Glucose , Humanos , Cintura Hipertrigliceridêmica/sangue , Cintura Hipertrigliceridêmica/epidemiologia , Masculino , Obesidade Infantil/sangue , Obesidade Infantil/epidemiologia , Fenótipo , Puberdade/fisiologia , Fatores de RiscoRESUMO
OBJECTIVE: To evaluate the correlation between neck circumference and insulin resistance and components of metabolic syndrome in adolescents with different adiposity levels and pubertal stages, as well as to determine the usefulness of neck circumference to predict insulin resistance in adolescents. METHODS: Cross-sectional study with 388 adolescents of both genders from ten to 19 years old. The adolescents underwent anthropometric and body composition assessment, including neck and waist circumferences, and biochemical evaluation. The pubertal stage was obtained by self-assessment, and the blood pressure, by auscultation. Insulin resistance was evaluated by the Homeostasis Model Assessment-Insulin Resistance. The correlation between two variables was evaluated by partial correlation coefficient adjusted for the percentage of body fat and pubertal stage. The performance of neck circumference to identify insulin resistance was tested by Receiver Operating Characteristic Curve. RESULTS: After the adjustment for percentage body fat and pubertal stage, neck circumference correlated with waist circumference, blood pressure, triglycerides and markers of insulin resistance in both genders. CONCLUSIONS: The results showed that the neck circumference is a useful tool for the detection of insulin resistance and changes in the indicators of metabolic syndrome in adolescents. The easiness of application and low cost of this measure may allow its use in Public Health services.