Venous Thrombosis Biomarkers in Sickle Cell Disease and Sickle Cell Trait

Study point of contact

Brenda F Merriweather, R.N.
(301) 480-5168
[email protected]

Locations

1 United States site

Age

18 to 80 Years

Genotypes

HbSS, HbSC, HbAS

Study type

Observational

Gender

All

Compensation

Unknown

About the study

Background:

Venous thromboembolism (VTE) includes the abnormal clotting of blood in a deep vein of the
upper or lower limbs (deep vein thrombosis) that may travel to and block a blood vessel in
the lung (pulmonary embolism). Some people with sickle cell disease (SCD)-a red blood cell
disorder-seem to be at greater risk for developing these blood clots. Researchers want to
study the blood of people with SCD and VTE as well as healthy people to develop better
treatments to prevent blood clots.

Objective:

To study blood clotting in SCD because it is the most common cause of vascular death after a
heart attack or stroke.

Eligibility:

People ages 18-80 who have SCD (with or without a history of blood clots) or the trait for
SCD, and healthy volunteers

Design:

Participants will be screened with medical history, physical exam, and medical records
review. They will give blood samples.

Participants will have phone calls either every 3 months or once a year, for 2 years. They
will give updates on their health. They may give additional medical records. The phone calls
may last up to 30 minutes.

If participants have a VTE or pain crisis episode, they may visit the Clinical Center. These
visits may last up to 4 hours. They will repeat the screening tests and give blood samples.

Some participants may be invited to take part in blood studies.

After 2 years, some participants will have a follow-up visit at the Clinical Center.

Participation will last for about 2 years.

participation requirements

Sickle cell disease with and without VTE

– Sickle cell disease (HbSS, HbSC and HbS/beta-thalassemia genotypes) in steady state.

– Diagnosis of at least one or more VTE within 5 years of study enrolment confirmed by
radiologic imaging (for SCD patients with VTE).

– Absence of clinical history of VTE (for SCD controls)

– Between 18 and 80 years of age.

– Ability to provide informed written consent.

Sickle cell trait

– Sickle cell disease (HbAS genotype).

– Absence of clinical history of VTE

– Between 18 and 80 years of age.

– Ability to provide informed written consent.

Ethnically matched controls

– Between 18 and 80 years of age.

– African, or of African descent.

– Ability to provide informed written consent.

– Absence of clinical history of VTE

participation restrictions

SCD with and without VTE

– Pregnancy (test done at enrollment; if a subject becomes pregnant during the study
period, samples will not be obtained while the subject is pregnant and the subject
will be taken off study).

– Patients on exchange transfusion or having received a simple blood transfusion in the
past 60 days.

– Active viral infection as evidenced by testing positive for hepatitis B surface
antigen or hepatitis C virus (HCV) antibody (Ab) with signs of active hepatitis B or C
virus infection. If the subject is positive for HCV Ab, a reverse
transcriptasepolymerase chain reaction test will be conducted. Subjects with hepatitis
C may be rescreened after receiving appropriate hepatitis C treatment.

– Testing positive for human immunodeficiency virus 1 or 2 Ab with evidence for ongoing
active infection (i.e., CD 4 count <400/microL and viral load >100,000 copies/ml) on
antiretroviral therapy.

– Active acute inflammatory disorders rheumatoid arthritis or systemic lupus
erythematosus on disease modifying therapy.

– Diabetes mellitus judged to be under poor control by the Investigator evidenced by a
single fasting sugar value >250gm/dl or requiring >3 antidiabetic agents, including
insulin (all insulins are considered 1 agent); use of insulin per se is not
exclusionary.

SCT and ethnically matched controls

– Diagnosis of any of the following chronic disease or conditions: Sickle cell disease
(HbSS, HbSC and HbS/beta-thalassemia genotypes).

– Clinical history of VTE.

– Pregnancy (test done at enrollment; if a subject becomes pregnant during the study
period, samples will not be obtained while the subject is pregnant and the subject
will be taken off study.

– Active viral infection as evidenced by testing positive for hepatitis B surface
antigen or hepatitis C virus (HCV) antibody (Ab) with signs of active hepatitis B or C
virus infection. If the subject is positive for HCV Ab, a reverse
transcriptasepolymerase chain reaction test will be conducted. Subjects with hepatitis
C may be rescreened after receiving appropriate hepatitis C treatment.

– Testing positive for human immunodeficiency virus 1 or 2 Ab with evidence for ongoing
active infection (i.e., CD 4 count <400/microL and viral load >100,000 copies/ml) on
antiretroviral therapy.

– Active acute inflammatory disorders rheumatoid arthritis or systemic lupus
erythematosus on disease modifying therapy.

– Diabetes mellitus judged to be under poor control by the Investigator evidenced by a
single fasting sugar value >250gm/dl or requiring >3 antidiabetic agents, including
insulin (all insulins are considered 1 agent); use of insulin per se is not
exclusionary.

Locations

  • Bethesda, Maryland, United States, National Institutes of Health Clinical Center, 20892 [Recruiting]
Last updated 2021-07-22 Enroll Now