Objectives: Adipose tissue-derived inflammation may contribute to metabolic alterations and eventually to the metabolic syndrome (MetS). The purpose of this study was to: (1) examine the role of adipocytokines in the association between obesity and the MetS and (2) to determine whether the association is different in obese and non-obese persons.
Design: Cross-sectional population-based InCHIANTI study.
Subjects: A total of 944 community-dwelling adults aged 65 years and older living in Tuscany, Italy.
Measurements: Obesity was defined as body mass index > or =30 kg/m2 and MetS as > or =3 of the ATP-III criteria. Circulating levels of C-reactive protein, interleukin (IL)-6, IL-1 receptor antagonist (IL-1ra), IL-18, tumour necrosis factor (TNF)-alpha R1, adiponectin, resistin and leptin were measured. Additionally, insulin resistance was determined using the homeostasis model assessment (HOMA-IR).
Results: The prevalence of the MetS was 32%. Both overall and abdominal obesity were significantly associated with the MetS after adjusting for inflammatory cytokines, adipokines and lifestyle factors. After adjusting for multiple confounders and HOMA-IR, IL-1ra, TNF-alpha R1 and adiponectin (P < 0.05) remained significantly associated with the MetS. Having multiple cytokines in the highest tertile increased the likelihood of having the MetS in both obese (P for trend 0.002) and non-obese persons (P for trend 0.001) independent of insulin resistance.
Conclusions: Non-obese and obese individuals who develop an intense pro-inflammatory state may be more prone to develop the MetS than those with lower levels of inflammation.