The Influence of micro-and Macro Vascular Dysfunction on Clinical Severity in Adults With Sickle Cell Anemia (SS) and Sickle Cell Hemoglobin C Disease (SC)

NCT ID: NCT07277023

Last Updated: 2025-12-11

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 49 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2016-04-29
• Study Completion Date: 2021-10-29

Brief Summary

The primary aim of this study is to determine the implication of micro and macro vascular function on the clinical severity of SCD (SS, SC, Sß°) adults. The secondary aim of this study is to understand the contribution of several parameters, known to influence vascular function in non-SCD individuals, in SCD

Detailed Description

TSCD patients are characterized by vascular alterations, with vascular function being severely affected. However, the exact contribution of vascular dysfunction in the clinical severity and the risk for frequent vaso-occlusive crises in SCD is unknown. Furthermore the factors involved in this imbalance remain unclear but it is supposed that cerebral hypoxia, the deficit in nitric oxide, abnormal blood rheology, increased microparticles levels, autonomic nervous system imbalance and a low level of physical activity as well as poor physical fitness might be involved.

• Primary outcome: The primary outcome of the present study is to characterize the level of alteration of micro and macro vascular function in SCD (SS, SC and Sß°) adults measured by heat-mediated vasodilation and peripheral perfusion (Laser Doppler system) and pulse wave velocity and to test relationships between this measured vascular function and clinical severity which is based on the rate of vaso-occlusive crisis (severe if ≥ 3 per year), the rate of acute chest syndrome (severe if > 0 per year) and/or the presence of chronic complications.
• Secondary outcomes: To test the existence of relationships between several factors: biological (hematology, blood rheology, nitric oxide and microparticles), physiological (the autonomic nervous system activity measured by Holter electrocardiogram and tissue oxygenation (muscular and cerebral)) and physical activity level (estimated by questionnaire and accelerometer) and physical fitness (estimated by the six minute walk test with oxygen consumption measurements).
• Study design: This study has been designed as biomedical, monocentric prospective and interventional study

Conditions

Sickle Cell Anemia

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: NONE

Study Groups

functions micro and macro-vascular in connection the clinical

To characterize the level of alteration of micro and macro vascular function in SCD (SS, SC and Sß°) adults measured by heat-mediated vasodilation and peripheral perfusion (Laser Doppler system) and pulse wave velocity and to test relationships between this measured vascular function and clinical severity which is based on the rate of vaso-occlusive crisis (severe if ≥ 3 per year), the rate of acute chest syndrome (severe if \> 0 per year) and/or the presence of chronic complications.

Group Type: OTHER

The influence of micro-and macro vascular dysfunction on clinical severity in adults with sickle cell anemia (SS) and sickle cell hemoglobin C disease (SC)

Intervention Type: DIAGNOSTIC_TEST

The study permit to characterize the level of alteration of micro and macro vascular function in SCD (SS, SC and Sß°) adults measured by heat-mediated vasodilation and peripheral perfusion (Laser Doppler system) and pulse wave velocity and to test relationships between this measured vascular function and clinical severity which is based on the rate of vaso-occlusive crisis (severe if ≥ 3 within the 2 preceding years) and the rate of acute chest syndrome (severe if \> 0 in the last 2 years).

Interventions

The influence of micro-and macro vascular dysfunction on clinical severity in adults with sickle cell anemia (SS) and sickle cell hemoglobin C disease (SC)

The study permit to characterize the level of alteration of micro and macro vascular function in SCD (SS, SC and Sß°) adults measured by heat-mediated vasodilation and peripheral perfusion (Laser Doppler system) and pulse wave velocity and to test relationships between this measured vascular function and clinical severity which is based on the rate of vaso-occlusive crisis (severe if ≥ 3 within the 2 preceding years) and the rate of acute chest syndrome (severe if \> 0 in the last 2 years).

Intervention Type: DIAGNOSTIC_TEST

Eligibility Criteria

Inclusion Criteria

• adults ≥ 18 years old,
• medical diagnosed with SCD (genotype SS, SC or Sß°) by isoelectrofocusing or HPLC at clinical steady state at the time of the study (i.e., no blood transfusion within the last three months,
• absence of acute episodes of infection, vaso-occlusive crisis or acute chest syndrome at least one month before inclusion in the study),
• regularly followed by the Sickle Cell Unit of the Academic Hospital of Pointe-à-Pitre (Guadeloupe) and having signed well informed the letter of agreement.

Exclusion Criteria

• not at "steady-state";
• pregnancy or breast feeding;
• non-compliant patients to usual care;
• no signed informed consent

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Centre Hospitalier Universitaire de la Guadeloupe

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Marie BILLAUD, Doctor in the Sickle Cell

Role: PRINCIPAL_INVESTIGATOR

Hospital University Center of Pointe-à-Pitre

Locations

Hospital University Center of Pointe-à-Pitre

Pointe-à-Pitre, Guadeloupe, Guadeloupe

Countries

Guadeloupe

Other Identifiers

RBM-PAP-2015/108

Identifier Type: -

Identifier Source: org_study_id