Muscularity and adiposity are differently associated with inflammatory and nutritional biomarkers among patients on hemodialysis and peritoneal dialysis

Purpose: Nutritional alterations are prevalent in patients undergoing hemodialysis (HD) and peritoneal dialysis (PD). We aimed at evaluating whether body composition parameters in HD vs PD are differently associated with nutritional and inflammatory biomarkers.

Methods: Body composition was assessed by bioimpedance analysis. Neutrophil to lymphocyte ratio (NLR), serum albumin and C-reactive protein were used as nutritional and inflammatory biomarkers. Multivariable linear regression analysis was used to determine association(s) of body composition parameters with biomarkers.

Results: We enrolled a total of 108 patients, 58 on HD and 50 on PD. Fat free mass percent was higher in HD patients than PD (p = 0.006) and higher extracellular water (ECW)/intracellular water (ICW) in HD compared to PD patients (p = 0.023), as well as fat mass index was greater in PD than HD (p = 0.004). In HD patients, albumin positively correlated with fat free mass (r = 0.42; p = 0.001) and ICW/h² (r = 0.31; p = 0.02). In PD, NLR positively correlated with fat mass (r = 0.36; p = 0.01), fat mass index (r = 0.37; p = 0.01) and ECW (r = 0.41; p = 0.005), and negatively correlated with fat free mass percent (r = -0.30; p = 0.04) and ICW percent (r = -0.34; p = 0.02). By linear regression analysis, in HD fat free mass index was associated with albumin and the absence of diabetes. In PD, the association of fat free mass index was present with NLR. Regarding adiposity, in HD we found no association of ECW/ICW with NLR and CRP, whereas in PD the ECW/ICW was associated with NLR.

Conclusion: Inflammation drives body composition changes with differences according to the type of dialysis, as expressed by the modulation of some circulating biomarkers.