OBJECTIVE: This cross-sectional study explores the association of adipokines and interleukin-6 (IL-6) with muscle and protein energy wasting (PEW) in children with chronic kidney disease (CKD).
METHODS: We measured serum adiponectin, leptin, resistin and IL-6 in 53 patients with CKD stage 3-5. Lean tissue (LTI) and fat tissue index (FTI) were estimated by bioimpedance analysis spectroscopy. PEW was defined as muscle wasting [LTI adjusted to height age (LTI HA) z-score <-1.65 SD) and at least two of the following: reduced body mass [body mass index adjusted to height age (BMI HA) z-score <-1.65 SD), poor growth [height z-score <-1.88 SD], questionnaire based decreased appetite, serum albumin ≤ 3.8 g/dl.
RESULTS: PEW, observed in 8 (15.1%) patients, was more prevalent in CKD stage 5 (p=0.010). Among the adipokines, adiponectin and resistin levels were significantly higher in CKD stage 5 (p<0.001, p=0.005). Adiponectin was correlated to LTI HA z-score (Rs=-0.417, p=0.002), leptin to FTI z-score (Rs=0.620, p<0.001), while no correlation was observed between resistin and body composition parameters. Resistin was the only adipokine correlated to IL-6 (Rs=0.513, p<0.001). After adjustment for CKD stage and patient age, PEW was associated with adiponectin and IL-6 rise by 1 μg/ml and 10 pg/ml respectively (OR 1.240, 95% CI 1.040, 1.478 and OR 1.405, 95% CI 1.075-1.836) but not with leptin, while resistin association with PEW lost its significance.
CONCLUSION: In pediatric CKD, adiponectin is associated with muscle wasting, leptin with adiposity and resistin with systemic inflammation. Adiponectin and cytokine IL-6 may serve as PEW biomarkers.