Blood Thickness and Exercise Limits in Polycythemia Vera
Studies blood thickness during exercise testing in adults with polycythemia vera.
Plain-language title generated from the registry record
Registry title: Potential Biological and Physiological Determinants for Exercice in Patients With Polycythemia Vera
Key facts
- Where
- Lyon, FranceSee the site
AI summary: who the study is looking for
From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.
The trial is looking for adults aged 18 to under 70 with polycythemia vera (confirmed JAK2 V617F mutation) who have been prescribed a cardiopulmonary exercise test because they want to resume regular physical activity.
- Age
- At least 18 years and under 70 years
- Sex
- All sexes can join
- Disease stage
- Polycythemia vera, followed for this diagnosis, with a cardiopulmonary exercise test (CPET) prescribed because of their wish to resume regular physical activity
- Biomarker or test result
- Confirmed JAK2 V617F mutation
Main reasons for not taking part
- Known heart disease or chronic lung illness (for example asthma) that could affect VO₂max on its own
- Known history of major thromboembolic complication
- Body mass index (BMI) greater than 35
- Taking part in another interventional research study that may interfere
- Under legal protection (guardianship, curatorship), currently receiving psychiatric care, or deprived of liberty
Read by machine on 12 November 2026.
Could this be for you?
Answer for yourself. This is not a decision: only the study team can say whether you can take part.
- Are you between 18 and 70 years old?
Source: NCT07341048, who can take part
Where in France
- Department of Sports Medicine and Physical Activity. Pulmonary Function Testing. Croix Rousse Hospital.Lyon, FranceContact: Emeric Stauffer, DrNo longer taking part
Questions to ask the study team
- How often do I need to come in, and for how long each time?
- Are travel costs paid?
- Can I keep my own doctor?
- What happens if I want to stop?
Contact the study team: see the registry record → Contacts and Locations
Print a page for my doctorTrial details
- Who runs it
- Hospices Civils de Lyon
- Trial code
- NCT07341048
- Record updated
- 15 January 2026
- Original description
Polycythemia vera (PV) is a rare haematological disorder characterized by an excessive production of red blood cells, associated with the somatic JAK2 V617F mutation. Clinical manifestations are varied and often include exercise intolerance but the underlying mechanisms remain poorly understood.Read full original descriptionShow less
Characterization of Exercise Intolerance in Patients With Polycythemia Vera: Study of Potential Biological and Physiological Determinants.
Polycythemia vera (PV) is a rare haematological disorder characterized by an excessive production of red blood cells, associated with the somatic JAK2 V617F mutation. Clinical manifestations are varied and often include exercise intolerance but the underlying mechanisms remain poorly understood.
Physical activity is recommended in the management of chronic diseases, but it must be tailored to the physiological profile of the patient. A cardiopulmonary exercise test (CPET) is essential to ensure safety, detect possible contraindications, and assess maximal oxygen uptake (VO₂max), a key indicator of aerobic performance.
This prospective, experimental, non-randomized study will include patients with PV followed at Lyon Sud University Hospital and for which a CPET is scheduled in their routine clinical follow-up. The primary objective is to compare VO₂max between two groups of patients: moderate (<10%) versus marked (≥10%) extent of blood viscosity increase after the completion of the CPET. The main hypothesis is that a significant increase in blood viscosity during exercise (≥10%) is a major limiting factor in oxygen transport and leads to a reduced VO₂max, reflecting impaired exercise tolerance.
Secondary analyses will focus on hemorheological parameters, tissue oxygenation, and cardiorespiratory and metabolic responses. The study aims to better understand the biological and physiological determinants of exercise intolerance in this population.
Inclusion: Patient aged at least 18 years and under 70; Patient followed for a diagnosis of Polycytemia vera (confirmed JAK2 V617F mutation) and who were prescribed a CPET because of their wish to resume regular physical activity; Patient affiliated with or benefiting from a social security scheme.
Exclusion: Subject currently receiving psychiatric care; Any known history of heart disease or chronic respiratory illness likely to affect VO₂max independently of Polycytemia vera (e.g., asthma), according to the investigator's judgment; Any known history of major thromboembolic complication, according to the investigator's judgment; Body mass index (BMI) greater than 35, according to the investigator's judgment; Participation in another interventional research protocol that may interfere with the present study, according to the investigator's judgment; Adult subject under legal protection measures (guardianship, curatorship); Subject deprived of liberty by judicial or administrative decision.