Inflammation and fatness in adolescents with and without Down syndrome: UP & DOWN study

Background The main objective of this study was to describe the inflammatory status of adolescents with Down syndrome (DS) and their relationship with adiposity. Methods Ninety‐five adolescents with DS (44.2% girls) and a control group of 113 adolescents (47.8% girls), aged between 11 and 18 years old, from the UP & DOWN study were included in this substudy. Serum C‐reactive protein, C3 and C4 complement factors, total proteins, interleukin‐6, tumour necrosis factor‐α, insulin, cortisol, leptin, adiponectin, galactin‐3 and visfatin were analysed; homeostatic model assessment index was calculated. In order to evaluate adiposity, we measured the following body fat variables: weight, height, waist circumference and skinfold thicknesses. Birth weight was obtained by questionnaire. In addition, body mass index, waist‐to‐height ratio (WHtR) and body fat percentage (BF%) were calculated. Results Down syndrome group showed higher levels of body mass index, WHtR, waist circumference, BF% and lower birth weight than controls (P < 0.001). In the general linear model in the total sample, WHtR was positively associated with C3 and C4 (P < 0.001) as well as with leptin levels (P = 0.015). BF% was positively associated with total proteins (P = 0.093) and leptin levels (P < 0.001). DS was positively associated with total proteins (P < 0.001), C3 (P = 0.047) and C4 (P = 0.019). Despite the higher levels of adiposity found in DS group, no direct association was found between BF% and leptin levels, comparing with the control group. Conclusions These findings suggest that abdominal obesity should be controlled in adolescents because of its relationship with acute phase‐inflammatory biomarkers but especially in DS adolescents who may show a peculiar metabolic status according to their relationship between adiposity and inflammatory biomarkers.We appreciate the following financial support: DEP 2010-21662-C04-00 grants from the National Plan for Research, Development and Innovation (R +D +i) MICINN