Copeptin Concentration Measured in Plasma Samples and Intradialytic Blood Pressure Variation (CODIALHYP)

Vasopressin is a key regulator of water and vascular homeostasis, acting through V2 receptors to control renal water reabsorption and through V1a receptors to influence vascular tone. Copeptin, a stable surrogate marker of vasopressin release, provides a reliable measure of vasopressin activity. In hemodialysis, where ultrafiltration and osmotic shifts challenge fluid balance, the contribution of vasopressin to intradialytic blood pressure regulation remains uncertain. Elevated copeptin levels in dialysis patients have been associated with interdialytic weight gain and adverse cardiovascular outcomes. This study (CODIALHYP) tests the hypothesis that vasopressin activity, assessed through copeptin levels, is associated with intradialytic hypertension. The primary objective is to evaluate the relationship between copeptin concentrations and blood pressure changes during hemodialysis. Secondary objectives include assessing whether vasopressin's antidiuretic effect is preserved in hemodialysis patients and exploring the contribution of other hormonal pathways involved in fluid and vascular regulation.

Study Overview

• Status: Active, not recruiting
• Conditions: Hemodialysis
• Intervention / Treatment: Diagnostic test: Routine biology samples et blood pressure mesures

Detailed Description

This study investigates the role of vasopressin activity, assessed through copeptin levels, in the hemodynamic changes occurring during hemodialysis. Vasopressin is involved in both water homeostasis and vascular regulation, yet its contribution to intradialytic blood pressure variations remains insufficiently characterized. Hemodialysis induces rapid shifts in osmotic gradients and extracellular volume, creating conditions in which vasopressinmediated mechanisms may influence vascular tone and fluid balance. The research is based on a retrospective observational design involving chronic hemodialysis patients. Clinical records were reviewed to collect blood pressure measurements obtained before, during, and after dialysis sessions, as well as laboratory data including copeptin, plasma osmolality, cortisol, and aldosterone.

When residual diuresis was present, urinary volume and osmolality were documented. Additional information related to dry weight, ultrafiltration parameters, and routine markers of fluid balance was extracted from standard clinical evaluations.

These data provide a framework for examining the association between vasopressin activity and intradialytic hypertension, and for exploring the contribution of other hormonal pathways involved in fluid and vascular regulation.

• Study Type: Observational
• Enrollment (Actual): 71

Contacts and Locations

Study Locations

• France
  • Vandœuvre-lès-Nancy, France, 54500
    • CHRU de NANCY

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

The study population consists of adult patients (≥18 years old) undergoing chronic hemodialysis for more than three months. All included patients were clinically stable, not hospitalized at the time of data collection, and received treatment within the ALTIR network (Association Lorraine pour le Traitement de l'Insuffisance Rénale).

Data were obtained from three hemodialysis centers: Nancy-Brabois, Champelle, and Épinal.

Description

Inclusion Criteria:

• Adult patients (≥18 years old).
• Undergoing chronic hemodialysis treatment > 3 months.
• Availability of routine predialysis blood samples for copeptin and biochemical measurements.
• Availability of blood pressure recordings before, during, and after hemodialysis sessions.

No exclusion criteria if inclusion criteria is filled

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Intervention / Treatment

Selected hemodialysis patients group; The study population consists of adult patients (≥18 years old) undergoing chronic hemodialysis for more than three months. All included patients were clinically stable, not hospitalized at the time of data collection, and received treatment within the ALTIR network (Association Lorraine pour le Traitement de l'Insuffisance Rénale). Data were obtained from three hemodialysis centers: Nancy-Brabois, Champelle, and Épinal.

Diagnostic test: Routine biology samples et blood pressure mesures; Copeptin concentration will be measured from routine plasma samples, and blood pressure values will be recorded before, during, and after hemodialysis sessions using standard clinical monitoring. The primary outcome is the association between copeptin levels and intradialytic blood pressure variation.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Copeptin Concentration Measured in Plasma Samples and Intradialytic Blood Pressure Variation	Copeptin concentration will be measured from routine plasma samples, and blood pressure values will be recorded before, during, and after hemodialysis sessions using standard clinical monitoring. The primary outcome is the correlation between copeptin levels and intradialytic blood pressure variation.	At baseline (M0) and at 3 months (M3), with copeptin measured at dialysis initiation (prehemodialysis) without additional blood sampling.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Plasma Osmolality	Plasma osmolality (mOsm/kg) will be obtained from routine predialysis laboratory measurements. These measurements will be used to evaluate whether the antidiuretic effect of vasopressin is preserved in hemodialysis patients.	Baseline (M0)
Copeptin level	Copeptin levels (pmol/L) will be obtained from routine predialysis laboratory measurements.	Baseline (M0)
Serum Cortisol and Aldosterone Concentrations	Serum cortisol and aldosterone concentrations will be measured from routine predialysis blood samples collected as part of standard care. These hormonal markers will be used to explore additional mechanisms potentially involved in intradialytic hypertension.	Baseline (M0)
Urinary Osmolality	Urinary volume and urine osmolality will be collected from standard clinical assessments in patients with residual diuresis. These measurements will be used to evaluate whether the antidiuretic effect of vasopressin is preserved in hemodialysis patients.	Baseline (M0)

Collaborators and Investigators

• Sponsor: Central Hospital, Nancy, France
• Collaborators: ALTIR Nancy

Study record dates

Study Major Dates

• Study Start (Actual): December 22, 2025
• Primary Completion (Estimated): March 1, 2026
• Study Completion (Estimated): March 1, 2026

Study Registration Dates

• First Submitted: February 11, 2026
• First Submitted That Met QC Criteria: February 23, 2026
• First Posted (Actual): February 27, 2026

Study Record Updates

• Last Update Posted (Actual): February 27, 2026
• Last Update Submitted That Met QC Criteria: February 23, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: Hemodialysis; Vasopressin; Fluid Balance; Intradialytic Hypertension; CTAVP; Copeption
• Additional Relevant MeSH Terms: Urogenital Diseases; Endocrine System Diseases; Male Urogenital Diseases; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Pituitary Diseases; Diabetes Insipidus
• Other Study ID Numbers: 2025PI192-671

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: The investigators designed the study as a pilot study and do not intend to share IPD with other study

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No