Disfunção endotelial e apneia do sono em adolescentes obesos

Abstract

Introduction. The increased prevalence of obesity worldwide is affecting the childhood and adolescence, which in the future will increase the prevalence of non-transmissible chronic diseases such as type 2 diabetes, since obese adolescents tend to become obese adults. Endothelial dysfunction is an early marker of cardiovascular risk. Objective: Determine whether obese adolescents, apparently healthy, have endothelial dysfunction and if cardiovascular risk factors and obstructive sleep apnea are associated with endothelial dysfunction. Methods. We studied 20 obese adolescents (OA; + 2 Z-score – WHO Growth standards, median age14 years, 100.9±20.3 kg) between 12 and 17 years, post pubescent, sedentary, who were not engaged in dietary or drug treatment, compared to 10 lean adolescents (LA, median age15 years, 54.4±5.3 kg) paired for sex. The metabolic syndrome risk factors (MetS, International Diabetes Federation), vascular function (flow-mediated dilation, FMD, and peripheral arterial tonometry RHI, EndoPAT®) and obstructive sleep apnea using the apnea-hypopnea index (AHI, polysomnography) were evaluated. Results. The OA group presented greater cervical circumference, greater abdominal circumference (107.9 [100-114.5] vs. 67.5 [66.4-73.7], p <0.001), as well as a greater amount and proportion of fat than the LA group. In addition, OA had higher triglyceride levels, SBP, DBP, LDL-c and lower levels of HDL-c than LA. In the OA group, 35% presented Mets, and 1 of the 20 subjects in the OA group did not have metabolic analysis. There was no difference between the 2 groups studied in relation to AHI (5.68±3.89 vs.3.11±3.41; p=0.161), and 86.6% in the OA group (Polysomnographic study in 15 subjects) and 50% in the LA group presented OSAS (AHI> 1). The OA group presented lower FMD compared to the LA group (6.17 ± 2.72 vs. 9.37 ± 2.20%, p = 0.005), but there were no differences between the groups in relation to VO2peak and RHI. Among all the risk factors studied, there was only a correlation between FMD percentage and WC (r = -0.506, p=0.008) e and FMD percentage and SBP (r=-0.493, p=0.006). Conclusion. Most adolescents, regardless of obesity, have OSAS. Obese adolescents presented Mets and endothelial dysfunction. The increase in WC and SBP appear to be involved in this dysfunction.