Different Immune Signature in Youths Experiencing Antipsychotic-Induced Weight Gain Compared to Untreated Obese Patients.

OBJECTIVES: To assess cytokine and chemokine levels in youth experiencing antipsychotic-induced weight gain (AIWG) compared to obese patients, hypothesizing a different "immune signature" between the two kinds of obesity. METHODS: We compared a group of youth experiencing AIWG (N 19, mean age 159 months, mean body mass index [BMI] z-score 1.81) and an age-, gender-, and BMI-matched group of untreated obese patients (N 19, mean age 147 months, mean BMI z-score 2) for a wide range of cytokines and chemokines by using a multiplex ELISA test. RESULTS: Platelet-derived growth factor (PDGF), interleukin (IL)1-?, IL4, IL8, IL9, IL12, IL 17, eotaxin, FGF, GMCSF, IP10, MIP1b, and vascular-endothelial growth factor (VEGF) were significantly lower in the AIWG group, whereas IL13 and RANTES were significantly higher. Controlling for age, sex, and BMI, PDGF, IL4, IL8, IL13, IL17, eotaxin, fibroblast growth factor (FGF), granulocyte-macrophage colony-stimulating factor (GMCSF), IP10, MIP1b, and VEGF remain significantly different. CONCLUSION: A clearly different pattern of cytokines distinguishes the two kinds of obesity, suggesting a different immune signature. Interestingly, most of the cytokines and chemokines bearing proinflammatory effects resulted decreased in the AIWG group, whereas IL-13, which holds an immune-modulatory effect, resulted increased.