Iron Mediated Vascular Disease in Sickle Cell Anemia Patients

Study Overview
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Brief Summary
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The purpose of this research study is to determine the frequency and severity of iron overload in patients with Sickle Cell Anemia and its relationship to blood vessel function. The investigators hypothesize that intermittent transfusions that these patients receive during hospitalizations produces significant iron overload and impairs blood vessel relaxation.

Detailed Description
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Patients with sickle cell anemia often require blood transfusion as part of the treatment for their disease. Each teaspoon of transfused blood contains about 5 mg of iron and the levels of iron in sickle cell patients increase rapidly with each transfusion. While iron is necessary for many bodily functions, too much iron damages blood vessels, liver, hormone producing glands (pancreas, pituitary and thyroid) and the heart. It is important to know how iron damages blood vessels because most of the problems experienced by sickle cell anemia patients (stroke, kidney failure, pulmonary hypertension, heart disease) result from blood vessel damage. In this trial, iron in the liver, pancreas, and kidney will be measured noninvasively by MRI while vascular function will be measured by ultrasound and tissue Doppler. Patients will be recruited primarily from the greater Los Angeles area, although patients from greater distances will be allowed to participate.

Official Title
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Iron-mediated Vascular Disease in Sickle Cell Disease.

Conditions
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Sickle Cell Disease

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age > 13 years Documented diagnosis of sickle cell anemia (SS, SC, Sß0, Sß+) Transfused no more than 8 times in a year. Exclusion Criteria: Cardiac pacemaker, implantable neurostimulator or other MRI incompatible device. History of extreme claustrophobia in MRI machine or other reason for inability to do MRI without sedation. Inability to be positioned on the MRI table for sufficient time to complete the MRI exams. Any medical or psychological condition that, in the opinion of the local investigator, would make it unsafe or ill-advised for the subject to participate. Currently not receiving chronic transfusion therapy, defined as greater than 8 transfusions per year.

Ages Eligible for Study
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Minimum Age: 13 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Liver iron concentration (LIC), pancreas R2*, and kidney R2*, measured by MRI | Liver iron concentration (LIC) will be used as a surrogate for total body iron, pancreatic iron represents a surrogate for extravascular iron deposition, and renal iron as a surrogate for chronic intravascular hemolysis. In addition, labile plasma iron will be measured in blood plasma. | 15 min MRI done completed during one time study visit | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Vascular function. | Measurements will be done through several procedures: Ultrasound of artery in upper arm, Ultrasound of artery in neck, and blood tests of ascorbate and hydrobiopterins. | Scheduled during one time study visit | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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sickle cell disease, sickle cell anemia, sickled cells, blood vessel, iron overload