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van CCT (UK)

van CCT (UK)

BLO2D Unlimited

- candidate number26828
- NTR NumberNTR6279
- ISRCTNISRCTN no longer applicable
- Date ISRCTN created
- date ISRCTN requested
- Date Registered NTR5-mrt-2017
- Secondary IDsNL61217.068.17 METC172011
- Public TitleBLO2D Unlimited
- Scientific TitleThe effect of repeated exercise at high altitude on blood coagulation
- hypothesisIt is hypothesized that strenuous exercise at high altitude causes increased thrombin generation, but that this effect will be attenuated during prolonged exposure and repeated exercise.
- Healt Condition(s) or Problem(s) studiedThrombosis, Blood coagulation, Physical activity, high altitude
- Inclusion criteria- Healthy male volunteer
- Age between 18 and 50 years old
- Exclusion criteria- Previous history of cardiovascular disease, pulmonary disease, bleeding disorder or venous thromboembolism
- Medication interfering with blood coagulation (low molecular weight heparins, vitamin K antagonists, direct oral anticoagulants, non-steroidal anti-inflammatory drugs)
- Impaired mobility
- Active smoking
- Not passing medical assessment
- Disapproval of contacting general practitioner in case of abnormalities found during medical assessment or during the study.
- mec approval receivedyes
- multicenter trialno
- randomisedno
- group[default]
- TypeSingle arm
- Studytypeobservational
- planned startdate 17-jun-2017
- planned closingdate30-jun-2017
- Target number of participants6
- Interventions- Strenuous physical exercise (heart rate reserve 60-85%) during 2 hours, once at sea level (baseline) and repeated 3x at high altitude (3,883 m above sea level)
- Venipuncture just before and immediately after exercise (8x27 ml)
- Primary outcomeTrombin generation
- Secondary outcome- Plasmin generation
- Platelet function test
- Thromboelastometry
- Blood count
- Fibrinolysis (clot lysis time)
- Coagulation factor analysis: von Willebrand factor (vWF), factor 8 (FVIII), D-dimers
- Biochemical markers: lactate, creatinine, urea, albumin

Other outcome parameters:
- Age
- Vital signs (heart rate, blood pressure and SpO2)
- Questionnaire (Lake Louise AMS)
- TimepointsN/A
- Trial web site
- statusstopped: trial finished
- Sponsor/Initiator Maastricht University Medical Center (MUMC+), Synapse Research Institute
- Funding
(Source(s) of Monetary or Material Support)
Synapse Research Institute
- Publications
- Brief summaryStrenuous exercise activates blood coagulation, mostly due to elevated platelet count, platelet hyperreactivity, increased thrombin generation and increased activity of several coagulation factors, especially factor 8 (FVIII) and von Willebrand factor (vWF). Mountaineering also appears to pose a risk for developing thrombosis. Healthy lowlanders moving to high altitude for a mean duration of 10 months were found to have a 30 times increased risk of developing a venous thromboembolism (VTE). Similarly, healthy soldiers stationed at high altitude were characterized by an almost 25-fold increased risk of developing deep calf vein thrombosis. Mountaineering usually involves repeated strenuous exercise, when walking, climbing, skiing or cycling. Because hypoxia and exercise both cause procoagulant changes, one might expect that exercise will amplify the altitude-induced hypercoagulability.

From 2 recent studies (Mont Blanc 1 and 2 studies), we concluded that hypoxia induces prothrombotic changes in blood. We have also found that strenuous exercise leads to prothrombotic changes (Red Meets Gold study), but these appear to be attenuated during repeated exercise (unpublished work). Mountaineering combines both hypoxia and repeated strenuous exercise.

In this study we aim to investigate the effect of 3x repeated strenuous exercise at high altitude on blood, using advanced techniques for studying thrombin generation, platelet function and fibrinolysis. It is hypothesized that high altitude and strenuous exercise cause increased thrombin generation, but that this effect will be attenuated during prolonged exposure and repeated exercise.
- Main changes (audit trail)METC goedkeuring verkregen op 01-jun-2017.
- RECORD5-mrt-2017 - 3-mrt-2018

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