1 Universidade de São Paulo, Brazil.
Introduction: Leptin and adiponectin are adipokines with inverse metabolic effects. While leptin associates with impaired glucose homeostasis, adiponectin increases insulin sensitivity. Adiponectin / leptin (A/L) ratio has been reported to be a useful parameter for assessing insulin resistance in both diabetic and healthy adults. Objectives: To verify the relationship between A/L ratio and markers of glucose metabolism among non-diabetic adolescents. Methods: Cross-sectional study with 63 adolescents aged 14 to 18 years old. Blood samples were collected to serum measurement of fasting glucose (enzymatic colorimetric method), insulin (chemiluminescence), leptin (ELISA) and adiponectin (ELISA). Height, weight, waist and hip circumferences were assessed in duplicate. Homeostasis model assessment estimates of insulin resistance (HOMACOMUNICACIONES IR) and beta-cell function (HOMA-beta), the quantitative insulin sensitivity check index (QUICKI), A/L ratio and body mass index (BMI) were calculated. Pearson’s correlation and Student’s T-test were performed using IBM SPSS Statistics Software 22.0. Results: From the total, 49.2% were male and 69.8% were overweight or obese. Subjects with weight excess presented higher leptin (46.3 ng/ mL, Standard Deviation – SD = 16.4 vs. 13.6 ng/mL, SD = 12.7; p < 0.0001) and lower adiponectin (19.3 μg/mL, SD = 15.4 vs. 26.7 μg/mL, SD = 17.7; p = 0.015) than normal weight subjects. A/L ratio positively correlated with QUICKI (r = 0.726; p<0.0001), and negatively correlated with waist circumference (r = -0.651; p<0.0001), hip circumference (r = -0.716; p<0.0001), insulin (r = -0.736; p<0.0001), HOMA-IR (r = -0.699; p<0.0001), HOMA-beta (r = -0.733; p<0.0001), weight (r = -0.608; p<0.0001) and BMI (r = -0.711; p<0.0001). Conclusions: A/L ratio strongly correlated with markers of glucose metabolism in a sample of non-diabetic adolescents, what indicates this measure may be a useful parameter when evaluating insulin resistance in this life stage.