Low Copeptin Levels in Patients With Intradialytic Hypotension.

Abstract

Intradialytic hypotension (IDH) is related to high morbidity and mortality. There is evidence that arginine-vasopressin (AVP) responses could play a role. Copeptin is a reliable biomarker of AVP. In this study, copeptin, aldosterone, epinephrine, and norepinephrine levels in patients with IDH were evaluated throughout a hemodialysis (HD) session and compared with the control group. The study includes 15 patients who were normotensive during HD and 15 patients with IDH with a minimum HD vintage of 1 year. Blood samples were collected before the initiation of an HD session (T0 ), in the mid-session for control group, 30 min after mean arterial pressure drop for IDH patients (T1 ), and at the end of the session (T2 ). Groups had similar demographic features and health parameters, interdialytic weight gains, and ultrafiltration amounts. The IDH group had a mean arterial pressure decline of 39.9 (±6.4) mm Hg. Copeptin levels of the control group increased an average of 79.9 (±97.5) pmol/L at T1 and an additional 24.8 (±33.9) pmol/L at T2 . In the IDH group, copeptin level increases at T1 and T2 were 3.2 (±5.5) pmol/L and 34 (±44.6) pmol/L, respectively. Copeptin levels of the IDH group were significantly lower at T1 (P < 0.001) and at the T0 -T2 interval than control group (P = 0.05). In the control group, aldosterone levels distinctly decreased, and in the IDH group, aldosterone levels were elevated (P < 0.001). Small changes were detected in epinephrine and norepinephrine levels for both groups but did not reach significance (P = 0.6 and P = 0.3, respectively). Lower copeptin level alterations suggest inadequate AVP responses in patients with IDH.