patients were malnourished. Plasma copeptin, proadrenomedullin, myeloperoxidase, protein, albumin, sodium and systemic blood pressure were not significantly different in each groups. Degrees of over-hydration were not different however, extracellular and intracellular fluid ratio (EI) were different in PD (p ¼ 0.03) and CKD-ND (p ¼ 0.12). EI were 1.08 vs. 0.94 for PD and 1.13 vs. 0.82 for CKD-ND. In pooled analysis, copeptin (0.44 6 0.28 vs 0.35 6 0.19, p ¼ 0.07) and EI (1.04 6 0.23 vs. 0.89 60.15, p ¼ 0.001) were different between malnutrition and normal group. CONCLUSIONS: Malnutrition CKD patients showed higher EI ratio. Even though the overall degree of over-hydration was not different, malnourished CKD patient showed more extracellular fluid accumulation despite similar oncotic pressure (albumin, protein) and plasma osmolality (sodium). This study showed the possibility of causal rela