Risk Factors for Venous Thromboembolism in the Community

This study has been completed.
Sponsor:
Collaborator:
Information provided by:
Mayo Clinic
ClinicalTrials.gov Identifier:
NCT00011180
First received: February 13, 2001
Last updated: December 5, 2012
Last verified: December 2012
  Purpose

To evaluate the trends in the incidence of venous thromboembolism, to determine the risk factors for venous thromboembolism in patients with medical and surgical illness, and to evaluate the efficacy of the anticoagulant therapy in reducing venous thromboembolism.


Condition
Cardiovascular Diseases
Thromboembolism

Study Type: Observational
Study Design: Observational Model: Case Control
Time Perspective: Retrospective
Official Title: Subtherapeutic Heparin Anticoagulation as a Predictor of Recurrent Venous Thromboembolism: A Population-Based Cohort Study

Resource links provided by NLM:


Further study details as provided by Mayo Clinic:

Primary Outcome Measures:
  • Mean time interval between commencing unfractionated heparin therapy and achieving a therapeutic activated partial thromboplastin time (aPTT) [ Time Frame: Day 1 in hospital ] [ Designated as safety issue: No ]
    The time interval (minutes) was measured retrospectively, using the electronic medical record for each subject.


Biospecimen Retention:   Samples With DNA

Plasma and genomic DNA


Enrollment: 385
Study Start Date: April 2001
Study Completion Date: May 2009
Primary Completion Date: May 2009 (Final data collection date for primary outcome measure)
Groups/Cohorts
Incident Cohort with VTE
Olmsted County, Minnesota residents with with a first-lifetime deep vein thrombosis (DVT) or pulmonary embolism (PE) during the five year period, 1996-2000.
Controls without VTE
Two Olmsted County, Minnesota residents without venous thromboembolism (VTE) were matched by age and gender to each definite or probable case of VTE within the 1996-2000 cohort.

Detailed Description:

BACKGROUND:

Venous thromboembolism (VTE) occurs frequently among patients hospitalized for major surgery or hospitalized for a medical illness primarily due to prolonged duration of immobilization. However, many patients undergo major surgery without any occurrence of VTE. Standard prophylactic therapy after surgery is heparin, which reduces the risk of VTE. However, heparin is associated with bleeding complications. Thus, it would be desirable to identify patients at high risk for VTE who might benefit the most from heparin therapy. An important focus of the study is to look at genetic factors which might play an important role in VTE incidence.

DESIGN NARRATIVE:

The study is a population based, retrospective case and case-control investigation of the genetic and environmental determinants of venous thromboembolism in the Rochester Minnesota Olmsted County population. The first five years of the study had three specific aims. The first specific aim was to update the 1966-1995 inception cohort to include Olmsted County residents with VTE during the five year period, 1996-2000. The second aim was to extend the analysis of risk factors for VTE by identifying two Olmsted County residents (controls) without VTE matched by age and gender to each definite or probable case within the 1996-2000 cohort, and to obtain plasma and genomic DNA from all cases and controls and perform a case-control study. The third specific aim was to evaluate the efficacy of anticoagulant therapy to prevent VTE recurrence.

The study was extended through March, 2009 to investigate trends in the incidence of venous thromboembolism, new risk factors including lipid-lowering, beta-blocker, and ACE-inhibitor therapies, and introduction of low molecular weight heparin (LMWH) therapy.

  Eligibility

Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Sampling Method:   Probability Sample
Study Population

Using the data resouces of the Rochester Epidemiology Project, we will update the 1966-1995 inception cohort to include Olmsted County, Minnesota residents with with a first-lifetime deep vein thrombosis (DVT) or pulmonary embolism (PE) during the five year period, 1996-2000. All subjects will be followed forward in time through their linked medical records in the community (retrospective cohort study), until death or the most recent clinical contact. For each subject, all inpatient and outpatient medical records of any local health care provider will be searched for vital status at last clinical contact. For deceased patients, all death certificates will be reviewed regardless of the patient location at death.

We also identified two Olmsted County residents (controls) without VTE matched by age and gender to each definite or probable case within the 1996-2000 cohort to perform a case-control study.

Criteria

No eligibility criteria

  Contacts and Locations
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Please refer to this study by its ClinicalTrials.gov identifier: NCT00011180

Locations
United States, Minnesota
Mayo Clinic
Rochester, Minnesota, United States, 55905
Sponsors and Collaborators
Mayo Clinic
Investigators
Principal Investigator: John Heit, MD Mayo Clinic
  More Information

Publications:

ClinicalTrials.gov Identifier: NCT00011180     History of Changes
Other Study ID Numbers: 864-98, R01HL066216
Study First Received: February 13, 2001
Last Updated: December 5, 2012
Health Authority: United States: Institutional Review Board

Keywords provided by Mayo Clinic:
Venous thromboembolism (VTE)
Deep vein thrombosis (DVT)
Pulmonary embolism (PE)

Additional relevant MeSH terms:
Cardiovascular Diseases
Thromboembolism
Venous Thromboembolism
Venous Thrombosis
Embolism and Thrombosis
Vascular Diseases
Thrombosis

ClinicalTrials.gov processed this record on July 20, 2014