Blood Viscosity in Polycythemia Patients

Not yet recruiting

• Conditions: Polycythemia, Primary; Polycythemia Secondary

• Registration Number: NCT06421025
• Lead Sponsor: Hospices Civils de Lyon

Brief Summary

Polycythemia (PG) corresponds to an increase in erythrocyte parameters on a blood test. A distinction is usually made between primary and secondary PG. The most common primary PG is Vaquez's disease, a hematological cancer. In Vaquez disease, an increase in hematocrit has been reported to be associated with a logarithmic increase in blood viscosity.

The main complications of primary PGs (especially in Vaquez disease) are thromboembolic complications. In contrast, thromboembolic complications are rarer in secondary PG. In Vaquez disease, a hematocrit ≤ 45% has been defined as the therapeutic goal for significantly reducing thromboembolic risk. However, this has not been established for secondary PGs. All in all, the definition of the 45% threshold is based solely on clinical studies with no obvious biological argument. What's more, simply lowering blood mass through cytoreduction alone does not appear to be sufficient to significantly reduce thromboembolic risk.

To investigator knowledge, there are no studies prospectively evaluating blood viscosity, its determinants and coagulation in different types of polycythemia. Nor are there any data on the direct effect on blood viscosity of the various treatments usually offered.

Detailed Description

Not available

Study Timeline

• Status Verified: 2024-05
• Study First Submitted: 2024-05-15
• Study First Submitted QC: 2024-05-15
• Last Update Submitted: 2024-05-19
• Study First Posted: 2024-05-20
• Last Update Posted: 2024-05-21
• Study Start: 2024-05-30
• Primary Completion: 2031-05-30
• Study Completion: 2031-05-30

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 160

Inclusion Criteria

• 18 years of age or older
• Followed for a diagnosis or suspicion of polycythemia (hematocrit greater than or equal to 49% in men and 48% in women), whatever the suspected etiology.
• Patient affiliated to a social security scheme or similar

Exclusion Criteria

• Patient having undergone therapeutic bloodletting within 3 months prior to inclusion, or having initiated cytoreductive therapy prior to inclusion.
• Any disease or condition other than polycythemia, chronic or not, likely to induce a change in blood viscosity (at the investigator's discretion)
• Patient participating in another interventional research protocol that may interfere with the present protocol (at the investigator's discretion).
• Patient under guardianship, curatorship or safeguard of justice
• Person under psychiatric care
• Patient under legal protection.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Whole blood viscosity levels in patients with polycythemia	Baseline	The investigators expect higher blood viscosity values in polyglobulic patients with symptoms of clinical hyperviscosity than in polyglobulic patients without symptoms of clinical hyperviscosity, but no differences in hematocrit between the two polycythemia groups

Trial Locations

Locations (1)

Service d'hématologie, Hôpital Lyon Sud; 🇫🇷 Pierre-Bénite, Lyon, France