AzTrials
AzTrials

Cardiovascular DiseasesNCT00005329

Protein S and Myocardial Infarction

An observational study of Cardiovascular Diseases and Heart Diseases, run by National Heart, Lung, and Blood Institute (NHLBI).

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
Search all trials

Trial summary

To test the hypothesis that low levels of free protein S, a natural anticoagulant protein in plasma, were associated with an increased incidence of myocardial infarction in middle aged men and women. Read more about this study

Who is it for?
Ages Up to 100 years, men only
How many people
Not given
Where
No sites listed yet
Study dates
May 1992to Mar 1997
Phase
Observational
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages Up to 100 years
  • Men only
  • No healthy volunteers
  • Child, Adult, Older adult

No eligibility criteria

About this study

To test the hypothesis that low levels of free protein S, a natural anticoagulant protein in plasma, were associated with an increased incidence of myocardial infarction in middle aged men and women.

Read the detailed description

BACKGROUND:

Free protein S (that portion of plasma protein S which is not in complex with C4b binding protein) is a cofactor for the anticoagulant effect of activated protein C. Patients presenting with acute myocardial infarction have significantly reduced levels of free protein S. If the major hypothesis proved correct, patients at high risk of myocardial infarction could be identified and could be targeted for future studies to examine specific intervention therapy.

DESIGN NARRATIVE:

The blinded and prospective study began in 1992, although the grant was first awarded in 1983. The goal was to determine if low levels of free protein S were associated with an increased incidence of myocardial infarction. Plasma samples were obtained yearly from 2,224 men aged 50-59 years who were participants in the Second Northwick Park Heart Study sponsored by the British Medical Research Council Epidemiology and Medical Care Unit. Clinical endpoints for the study were documented fatal and non-fatal myocardial infarction. To prevent potential bias, this laboratory was blinded to the clinical endpoints until all samples had been collected and all causes of death in the study population had been adjudicated. ln addition to free protein S, total protein S and C4b binding protein were measured. The study design permitted the assessment of the temporal relationship between the development of low free protein S levels and the occurrence of myocardial infarction and the presence or absence of a biologic gradient (dose-response) between levels of free protein S and the frequency of infarction. These two analyses were important in assessing whether the observed association was causal or whether low protein S occured as a consequence of myocardial infarction. Three levels of free protein S had been defined prior to initiating the study to determine if the frequency of myocardial infarction did follow a biologic gradient. The measurement of other potential markers of risk by other laboratories, such as prothrombin fragment Fl+2 and factor X activation peptide, permitted a comprehensive evaluation of hemostatic risk factors in myocardial infarction. A second study was conducted in women to examine protein S as a risk factor for myocardial infarction.

The study completion date listed in this record was obtained from the "End Date" entered in the Protocol Registration and Results System (PRS) record.

Medical subject headings
Cardiovascular Diseases, Heart Diseases, Myocardial Infarction

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted26 May 2000 (estimated)
  2. Study startMay 1992
  3. Study completionMar 1997

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Observational
IDs, dates and publications
ClinicalTrials.gov ID
NCT00005329
Sponsor's protocol ID
4128
Other IDs
R01HL030443
Status last verified
Mar 2005
First submitted
25 May 2000
Last updated
13 May 2016
Results posted
No

Publications

  • Eichner JE, Moore WE, McKee PA, Schechter E, Reynolds DW, Qi H, Comp PC. Fibrinogen levels in women having coronary angiography. Am J Cardiol. 1996 Jul 1;78(1):15-8. doi: 10.1016/s0002-9149(96)00219-6.

    PubMed 8712111
  • Thorisdottir H, Evans JA, Schwartz HJ, Comp P, Haluschak J, Ratnoff OD. Some clotting factors in plasma during danazol therapy: free and total protein S, but not C4b-binding protein, are elevated by danazol therapy. J Lab Clin Med. 1992 Jun;119(6):698-701.

    PubMed 1534346
  • Rudnicka AR, Miller GJ, Nelson T, Doray D, Comp PC. An association between plasma free protein s concentration and risk of coronary heart disease in middle-aged men. Thromb Res. 2001 Jan 15;101(2):1-11. doi: 10.1016/s0049-3848(00)00379-0.

    PubMed 11342201

Questions about this trial

What is this clinical trial studying?

An observational study of Cardiovascular Diseases and Heart Diseases, run by National Heart, Lung, and Blood Institute (NHLBI).

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 13 May 2016. Status can change between updates, so confirm with the study contact before making plans.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT00005329, which also lists 3 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 13 May 2016.

Free account

Log in to keep searching

You’ve used your 3 free searches. AzTrials is free: log in or create a free account to keep searching clinical trials and save the ones you want to follow.

Create a free accountLog in