Abstract: Objective To study the correlation between plasma asymmetric dimethylarginine (ADMA) level and blood pressure change during hemodialysis (HD) session in end-stage renal disease patients. Methods Thirty-one patients on maintenance hemodialysis (MHD) for more than six months were enrolled in this study. They had appropriate dry body weight detected by bioelectrical impedance. Based on intradialytic blood pressure change, the 31 MHD patients were divided into intradialytic hypertension, hypotension and stable blood pressure groups. Plasma ADMA was measured by enzyme linked immunosorbent assay (ELISA) before and after HD session. The correlation between ADMA and blood pressure change during HD session was investigated. The possible influential factors including metabolic bone disease indexes, electrolytes, nutrition status, micro-inflammatory status, serum lipids, pulse pressure difference, and antihypertensive therapy were compared between the three groups. Results Plasma ADMA elevated at the beginning and fell at the end of HD sessions in MHD patients (3.37±1.48 μmol/L vs. 1.71±0.80 μmol/L), both higher than the normal reference interval from foreign countries. The plasma ADMA values before and after HD were significantly higher in the intradialytic hypotension group (4.38±1.56 μmol/L and 2.25±0.83 μmol/L, respectively) than in the intradialytic hypertension group (2.70±1.18 μmol/L and 1.32±0.60 μmol/L, respectively; P=0.006) and intradialytic stable blood pressure group (2.78±0.88 μmol/L and 1.43±0.56 μmol/L, respectively; P=0.006). The pulse pressure difference was significantly higher in intradialytic hypertension group (62.41±11.57 mmHg) than in
intradialytic hypotension group and intradialytic stable blood pressure group (48.80±12.88 mmHg and 44.56±8.30 mmHg, respectively; P =0.004). Alkaline phosphatase (ALP), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C) and high-sensitivity c-reactive protein (Hs-CRP) were higher in intradialytic hypertension and intradialytic hypotension groups than in intradialytic stable blood pressure group (P<0.05), but were statistically insignificant between intradialytic hypertension and hypotension groups (P＞0.05). Conclusion ADMA was significantly elevated in MHD patients with appropriate dry body weight. The intradialytic blood pressure fluctuation was closely related to endothelial dysfunction, micro- inflammation and vascular
stiffness.

Key words: Hemodialysis, Asymmetric Dimethylarginine, Intradialytic hypertention, Intradialytic hypotention