Clinical Trial: Sickle Cell Trait and the Risk of Venous Thromboembolism

Study Status: Terminated
Recruit Status: Terminated
Study Type: Observational

Official Title: Sickle Cell Trait and the Risk of Venous Thromboembolism

Brief Summary: The purpose of this trial is to investigate D-Dimer levels, a surrogate marker of venous thromboembolism, in pregnant/postpartum white women as compared to pregnant/postpartum black women, and pregnant/postpartum women with sickle cell trait. The investigators will determine whether increased D-Dimer levels are reflected in a greater incidence of thrombosis in the postpartum patient, as well as the prevalence of symptomatic venous thrombosis in black patients as compared to pregnant white patients and women with sickle cell trait. The investigators will also investigate the effect of blood group on these parameters. If there is evidence that there is an increased risk of thrombosis in sickle cell trait, the investigators will plan a trial of prophylactic anticoagulation during the last trimester and the four weeks post partum for patients with sickle cell trait and compare this population to patients who do not receive prophylactic anticoagulation.

Detailed Summary:

Venous thromboembolism is the major cause of maternal mortality in the United States and there are emerging data that the thrombotic risk is higher in peripartum black women as compared to white women. The reasons are unclear: indeed, the few genetic risk factors for venous thrombosis that have been identified are more common in whites than blacks. This raises the possibility of yet undescribed mutations. To bolster this theory, some intriguing studies have noted a similar frequency of 'familial' thrombosis in blacks and whites, supporting the existence of yet unidentified hereditary component(s). Sickle cell anemia is a genetic disease more prevalent in the black population. Whereas sickle cell anemia has been associated with a prothrombotic state, there are limited data to support a prothrombotic state in sickle cell trait. We plan to examine whether sickle cell trait might play a role in increasing the incidence of thrombosis in the black population.

Peripartum women are 4-5 times more likely to develop venous thrombosis. Scant literature exists on the thrombotic risk in women from different races in the peripartum period and there are no studies evaluating venous thrombosis risk in sickle cell trait women during this time of increased thrombogenicity. In a retrospective analysis of deliveries of 12,000 women at Einstein/Montefiore, a higher incidence of venous thrombosis in black peripartum women was observed and, among the black population, a trend for sickle cell trait women to be at higher risk compared to black women with the normal hemoglobin (Hb) AA.

Given the medical importance and financial/sociological impact of venous thrombosis, it is important to determine whether black women, and specifically black women with sickle cell trait, are really at increased risk for thromboembolic disease during the peripartum p
Sponsor: Albert Einstein College of Medicine, Inc.

Current Primary Outcome: To investigate whether D-Dimer levels differ in black peripartum women with SCT than in black women with Hb AA and white women with Hb AA. [ Time Frame: One year ]

The primary outcome measure will be D-Dimer measured on a continuous scale. We will compare mean D-Dimer of Black SCT women, Black AA women and White AA women using an independent samples t tests if normality assumptions are met and Mann-Whitney test of mean ranks if not. We will use a one-sided, non-inferiority test of


Original Primary Outcome: Same as current

Current Secondary Outcome:

Original Secondary Outcome: Thromboprophylaxis for peripartum SCT [ Time Frame: 3 years ]

If there is evidence of an increased risk of thrombosis, we will investigate whether therapeutic intervention is beneficial by planning a trial of prophylactic anticoagulation during the peripartum period for women with SCT.


Information By: Albert Einstein College of Medicine, Inc.

Dates:
Date Received: June 21, 2010
Date Started: July 2010
Date Completion:
Last Updated: April 15, 2015
Last Verified: April 2015