Objective: Patients with chronic kidney disease (CKD) are susceptible to systemic inflammation and nutritional disorders, which are associated with morbidity and mortality. The aim of the present study was to evaluate the relationship between nutritional status, lean body mass, physical activity, and systemic inflammation in patients with stage 3-5 non-dialysis-dependent CKD.

Methods: A total of 55 predialysis patients with CKD were included in this cross-sectional study. Patients were divided into two groups according to the Subjective Global Assessment: 35 with normal nutritional status (NN) and 20 with malnutrition (MN). Anthropometric measurements, fat-free mass, muscle strength, physical activity, biochemical parameters, and serum cytokine levels of the patients were compared.

Results: Patients with CKD and malnutrition (CKD-MN) had higher serum phosphate, interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF)-α levels and lower serum albumin levels and blood lymphocyte counts than those with CKD-NN independent from glomerular filtration rate. Regression analysis showed a relationship between MN and serum phosphate level, blood lymphocyte count, and serum IL-6 and TNF-α levels. Muscle strength and gait speed showed a positive relationship with nutritional status and negative relationship with inflammation.

Conclusion: An increased inflammatory environment in patients with non-dialysis-dependent CKD was significantly associated with MN and decreased physical activity. An increased serum phosphate level appears to contribute to this MN-inflammation environment.

Keywords: Cytokine, inflammation, kidney failure, malnutrition, predialysis