Relation of chemokines to BMI and insulin resistance at ages 18-21

Objective:In obesity, adipose tissue becomes a significant source of chemokines and inflammatory cytokines that are associated with chronic systemic low-grade inflammation and may lead to insulin resistance. Studies in children have mainly focused on inflammatory cytokines and there are limited data for chemokines in adolescents and young adults. We studied the relation of chemokines to cardiovascular (CV)-risk factors, insulin resistance and adipocytokines in 18-21-year-old individuals.Subjects and Design:Cross-sectional data collected in a cohort originally enrolled at mean age 13, with data for the present study obtained from 252 examined at age 18.7±0.1 years.Methods:Multiple linear regression models were used to analyze the associations among chemokines (monocyte chemotactic protein-1, macrophage inflammatory protein-1β (MIP-1β), visfatin and interleukin-8 (IL-8)) and between chemokines and body mass index (BMI), glucose, lipids, blood pressure (BP), insulin resistance (euglycemic hyperinsulinemic clamp) and adipocytokines (IL-6, TNF- and adiponectin).Results:Chemokine levels were significantly intercorrelated. Significant associations (P<0.05) with adjustment for age, race and sex included: MIP-1β with waist circumference and IL-6, IL-8 with systolic BP and visfatin with IL-6. No other significant relations were found between the chemokines and the other variables. Further adjustment for BMI did not alter these conclusions.Conclusion:Considered in the context of prior studies in children and adults, these results suggest that in large part, the association between chemokines and CV risk or inflammatory factors does not appear to develop until adult life.