Blood Flow and Pain Crises in People With Sickle Cell Disease
| Status: | Completed |
|---|---|
| Conditions: | Anemia |
| Therapuetic Areas: | Hematology |
| Healthy: | No |
| Age Range: | 18 - 99 |
| Updated: | 10/11/2018 |
| Start Date: | March 21, 2012 |
| End Date: | October 5, 2018 |
Measurement of the Reactive Hyperemia Index in Sickle Cell Patients During Pain Crisis and After Recovery
Background:
- Many people with sickle cell disease have repeated episodes of severe pain that lasts for
days, requiring hospital care. These episodes, called pain crises, may be caused by changes
in blood flow. Researchers want to study blood flow in people with sickle cell disease who
are having a pain crisis and compare it with their blood flow after the pain crisis has
resolved. They also want to compare these measurements against blood flow in healthy people
who do not have sickle cell disease.
Objectives:
- To study whether changes in blood flow cause pain crises in people with sickle cell
disease.
Eligibility:
- Individuals at least 18 years of age who have sickle cell disease and are being treated
for a pain crisis.
- Individuals at least 18 years of age who have sickle cell disease and are not
experiencing a pain crisis.
- Healthy volunteers matched by age and gender with the participants who have sickle cell
disease.
Design:
- Participants will be screened with a physical exam and medical history. Blood and urine
samples will be collected.
- Participants having a sickle cell pain crisis will have two visits, one during the
crisis and one about 4 weeks after the crisis has resolved.
- Participants not having a sickle cell pain crisis will have one or two study visits.
Blood samples will be collected during at least one of these visits.
- Healthy volunteers will have one or two study visits. Blood samples will be collected
during at least one of these visits.
- During each visit for all participants, cameras and blood flow monitoring equipment will
be used to measure blood flow in the forearm.
sickle cell disease.
- Many people with sickle cell disease have repeated episodes of severe pain that lasts for
days, requiring hospital care. These episodes, called pain crises, may be caused by changes
in blood flow. Researchers want to study blood flow in people with sickle cell disease who
are having a pain crisis and compare it with their blood flow after the pain crisis has
resolved. They also want to compare these measurements against blood flow in healthy people
who do not have sickle cell disease.
Objectives:
- To study whether changes in blood flow cause pain crises in people with sickle cell
disease.
Eligibility:
- Individuals at least 18 years of age who have sickle cell disease and are being treated
for a pain crisis.
- Individuals at least 18 years of age who have sickle cell disease and are not
experiencing a pain crisis.
- Healthy volunteers matched by age and gender with the participants who have sickle cell
disease.
Design:
- Participants will be screened with a physical exam and medical history. Blood and urine
samples will be collected.
- Participants having a sickle cell pain crisis will have two visits, one during the
crisis and one about 4 weeks after the crisis has resolved.
- Participants not having a sickle cell pain crisis will have one or two study visits.
Blood samples will be collected during at least one of these visits.
- Healthy volunteers will have one or two study visits. Blood samples will be collected
during at least one of these visits.
- During each visit for all participants, cameras and blood flow monitoring equipment will
be used to measure blood flow in the forearm.
sickle cell disease.
Severe recurrent pain is the most common cause of acute morbidity in sickle cell disease1.
The underlying pathogenesis was initially thought to be ischemia from obstruction of
capillary beds by stiffened red blood cells; however, there is evidence that other factors
contribute to the pathogenesis of sickle cell pain crisis, such as inflammation and
coagulation, ischemia-reperfusion injury, angiogenesis balance, and vasomotor tone processes
that are regulated by endothelial nitric oxide.
Recent clinical data suggest that subjects with sickle cell disease suffer from chronically
impaired nitric oxide bioavailability. This has been attributed to increased consumption of
nitric oxide by hemoglobin and reactive oxygen species, or decreased production of nitric
oxide by endothelial cells; however the roles of nitric oxide bioavailability and endothelial
dysfunction during acute pain crisis are controversial and incompletely understood. Although
there have been several studies of endothelial function in steady state sickle cell disease,
there has been no comprehensive study of endothelial function during pain crisis.
In this study, our primary objective is to measure the reactive hyperemia index (a measure of
the endothelial response to shear stress) in twenty sickle cell subjects during acute pain
crisis and to compare it with the reactive hyperemia index measured after recovery from pain
crisis. This will identify whether there are acute changes in endothelial cell function
during sickle cell pain crisis. Our secondary objective is to compare the reactive hyperemia
index of thirty-five sickle cell subjects in steady state versus the reactive hyperemia index
of thirty-five healthy control subjects. This will identify whether there are chronic
differences in endothelial function between sickle cell subjects and healthy control
subjects.
This study will determine if there are defects in endothelium-dependent vasodilation in
response to shear stress during sickle cell pain crisis. Moreover, this study provides an
opportunity to evaluate new physiologic biomarkers of sickle cell pain crisis based on
measurements of blood flow, temperature, and oxygenation in the skin. These measurements may
serve as clinical endpoints in future studies of disease pathogenesis or therapeutic
interventions for sickle cell disease.
The underlying pathogenesis was initially thought to be ischemia from obstruction of
capillary beds by stiffened red blood cells; however, there is evidence that other factors
contribute to the pathogenesis of sickle cell pain crisis, such as inflammation and
coagulation, ischemia-reperfusion injury, angiogenesis balance, and vasomotor tone processes
that are regulated by endothelial nitric oxide.
Recent clinical data suggest that subjects with sickle cell disease suffer from chronically
impaired nitric oxide bioavailability. This has been attributed to increased consumption of
nitric oxide by hemoglobin and reactive oxygen species, or decreased production of nitric
oxide by endothelial cells; however the roles of nitric oxide bioavailability and endothelial
dysfunction during acute pain crisis are controversial and incompletely understood. Although
there have been several studies of endothelial function in steady state sickle cell disease,
there has been no comprehensive study of endothelial function during pain crisis.
In this study, our primary objective is to measure the reactive hyperemia index (a measure of
the endothelial response to shear stress) in twenty sickle cell subjects during acute pain
crisis and to compare it with the reactive hyperemia index measured after recovery from pain
crisis. This will identify whether there are acute changes in endothelial cell function
during sickle cell pain crisis. Our secondary objective is to compare the reactive hyperemia
index of thirty-five sickle cell subjects in steady state versus the reactive hyperemia index
of thirty-five healthy control subjects. This will identify whether there are chronic
differences in endothelial function between sickle cell subjects and healthy control
subjects.
This study will determine if there are defects in endothelium-dependent vasodilation in
response to shear stress during sickle cell pain crisis. Moreover, this study provides an
opportunity to evaluate new physiologic biomarkers of sickle cell pain crisis based on
measurements of blood flow, temperature, and oxygenation in the skin. These measurements may
serve as clinical endpoints in future studies of disease pathogenesis or therapeutic
interventions for sickle cell disease.
- INCLUSION CRITERIA FOR SUBJECTS WITH SICKLE CELL DISEASE IN PAIN CRISIS:
1. Age 18 years or older.
2. Diagnosis of sickle cell anemia:
1. Diagnosis of sickle cell disease (electrophoresis or HPLC documentation of
hemoglobin SS, SC, S-beta-thalassemia or other hemoglobinopathies causing
sickle cell disease is required).
2. Acute onset pain crisis in a distribution typical for that subject, onset
within the last 7 days and for which hospitalization and parenteral narcotic
pain treatment are required.
3. Ability to provide informed written consent.
EXCLUSION CRITERIA FOR SUBJECTS WITH SICKLE CELL DISEASE IN PAIN CRISIS:
1. Pregnancy.
2. History of non-trivial injury, burns, surgery or skin ulcers on the arms.
3. Carrier of drug resistant bacteria that normally requires isolation while visiting a
hospital.
4. Administration of any of the following drugs within the last 14 days:
- Phosphodiesterase-5 inhibitors (sildenafil, vardenafil, tadalafil)
- Endothelin-1 receptor blockers (bosentan, sitaxentan, ambrisentan, tezosentan)
- Nitric oxide donors (nitroglycerin, nitroprusside, nitrates)
5. Ingestion of caffeine within the 12 hours before the start of the study appointment,
or tobacco use within the 30 days before the study appointment.
6. Diagnosis with any of the following chronic diseases or conditions:
- Uncontrolled high blood pressure (systolic blood pressure must not be greater
than 160 mmHg or diastolic blood pressure greater than 90 mmHg)
- Uncontrolled high cholesterol (total cholesterol must not be greater than 240
mg/dL)
- Uncontrolled diabetes (must not have both a documented history of diabetes and
random blood glucose of greater than 200 mg/dL)
- Chronic kidney disease (serum creatinine must not be greater than 2 mg/dL)
- Coronary artery disease
- Peripheral vascular disease
7. Received a blood transfusion within 7 days of the study procedure.
SICKLE CELL DISEASE SUBJECTS IN STEADY STATE
INCLUSION CRITERIA FOR SUBJECTS WITH SICKLE CELL DISEASE IN STEADY STATE:
1. Age 18 years or older.
2. Diagnosis of sickle cell anemia:
a.Diagnosis of sickle cell disease (electrophoresis or HPLC documentation of
hemoglobin SS, SC, S-beta-thalassemia or other hemoglobinopathies causing sickle cell
disease is required).
3. Ability to provide informed written consent.
EXCLUSION CRITERIA FOR SUBJECTS WITH SICKLE CELL DISEASE IN STEADY STATE:
1. Pregnancy.
2. History of non-trivial trauma, burns, surgery or skin ulcers on the arms.
3. Carrier of drug resistant bacteria that normally requires isolation while visiting a
hospital.
4. Experience of an acute pain crisis requiring intravenous (IV) narcotics and hospital
admission within the last 14 days.
5. Ingestion of caffeine within the 12 hours before the start of the study appointment,
or tobacco use within the 30 days before the study appointment.
6. Administration of any of the following drugs within the last 14 days:
- Phosphodiesterase-5 inhibitors (sildenafil, vardenafil, tadalafil)
- Endothelin-1 receptor blockers (bosentan, sitaxentan, ambrisentan, tezosentan)
- Nitric oxide donors (nitroglycerin, nitroprusside, nitrates)
7. Diagnosis of any of the following chronic diseases or conditions:
- Uncontrolled high blood pressure (systolic blood pressure must not be greater
than 160 mmHg or diastolic blood pressure greater than 90 mmHg)
- Uncontrolled high cholesterol (total cholesterol must not be greater than 240
mg/dL)
- Uncontrolled diabetes (must not have both a documented history of diabetes and
random blood glucose of greater than 200 mg/dL)
- Chronic kidney disease (serum creatinine must not be greater than 2 mg/dL)
- Coronary artery disease
- Peripheral vascular disease
8. Received a blood transfusion within 7 days of the study procedure.
HEALTHY CONTROL SUBJECTS
INCLUSION CRITERIA FOR HEALTHY CONTROL SUBJECTS
1. Age 18 years or older.
2. African, of African descent or Hispanic
3. Ability to provide informed written consent.
EXCLUSION CRITERIA FOR HEALTHY CONTROL SUBJECTS
1. Pregnancy.
2. History of non-trivial injury, burns, surgery or skin ulcers on the arms.
3. Carrier of drug resistant bacteria that normally requires isolation while visiting a
hospital.
4. Administration of any of the following drugs within the last 14 days:
- Phosphodiesterase-5 inhibitors (sildenafil, vardenafil, tadalafil)
- Endothelin-1 receptor blockers (bosentan, sitaxentan, ambrisentan, tezosentan)
- Nitric oxide donors (nitroglycerin, nitroprusside, nitrates)
5. Ingestion of caffeine in the 12 hours before the start of the study appointment, or
used tobacco in the 30 days before the study appointment.
6. Diagnosis with any of the following chronic diseases or conditions:
- Sickle cell disease
- Uncontrolled high blood pressure (systolic blood pressure must not be greater
than 160 mmHg or diastolic blood pressure greater than 90 mmHg)
- Uncontrolled high cholesterol (total cholesterol must not be greater than 240
mg/dL)
- Uncontrolled diabetes (must not have both a documented history of diabetes and
random blood glucose of greater than 200 mg/dL)
- Chronic kidney disease (serum creatinine must not be greater than 2 mg/dL)
- Coronary artery disease
- Peripheral vascular disease
We found this trial at
1
site
9000 Rockville Pike
Bethesda, Maryland 20892
Bethesda, Maryland 20892
Click here to add this to my saved trials
