Race modifies the association between adiposity and inflammation in patients with chronic kidney disease: findings from the chronic renal insufficiency cohort study.

ABSTRACT

OBJECTIVE: The race-specific association of inflammation with adiposity and muscle mass in subjects with chronic kidney disease (CKD) was examined. METHODS: Plasma concentration of interleukin (IL)-1ß, IL-1 receptor antagonist (IL-1RA), IL-6, IL-10, tumor necrosis factor (TNF)-α, TGF-ß, high-sensitivity C-reactive protein (hs-CRP), fibrinogen, and serum albumin was measured in 3,939 Chronic Renal Insufficiency Cohort study participants. Bioelectric impedance analysis was used to determine body fat mass (BFM) and fat-free mass (FFM). RESULTS: Plasma levels of hs-CRP, fibrinogen, IL-1RA, IL-6, and TNF-α increased and serum albumin decreased across the quartiles of body mass index. In multivariable analysis, BFM and FFM were positively associated with hs-CRP, fibrinogen, IL-1ß, IL-1RA, and IL-6. One standard deviation (SD) increase in BFM and FFM was associated with 0.36 (95% confidence interval [CI] = 0.33, 0.39) and 0.26 (95% CI = 0.22, 0.30) SD increase in log-transformed hs-CRP, respectively (P < 0.001). Race stratified analysis showed that the association between biomarkers and BFM and FFM differed by race, with Caucasians, demonstrating a stronger association with markers of inflammation than African Americans. CONCLUSIONS: BFA and FFM are positively associated with markers of inflammation in patients with CKD. Race stratified analysis showed that Caucasians have a stronger association with markers of inflammation compared to African Americans.