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Observational Aspirin Use and CVD in the Physicians' Health Study

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00005493
Recruitment Status : Completed
First Posted : May 26, 2000
Last Update Posted : March 16, 2016
Information provided by:
National Heart, Lung, and Blood Institute (NHLBI)

Brief Summary:
To analyze existing data from the Physicians Health Study (PHS), a randomized primary prevention trial of low-dose aspirin and beta carotene conducted among 22,071 U.S. male physicians, to address questions concerning aspirin and cardiovascular (CV) disease that could not adequately be addressed during the randomized aspirin period.

Condition or disease
Cardiovascular Diseases Coronary Disease Heart Diseases Myocardial Infarction Cerebrovascular Accident

Detailed Description:


The aspirin component of the trial was terminated on January 25, 1988, due to a demonstrated benefit of aspirin on myocardial infarction. At that time, however, the number of strokes and CV deaths experienced by trial participants was inadequate to definitively evaluate these endpoints. The beta carotene component of the trial continued uninterrupted until its scheduled termination in December, 1996. During this period detailed information continued to be collected on post-trial aspirin use through annual questionnaires. As of October, 1995, the number of deaths, including cardiovascular deaths, had increased fourfold from that in the randomized period, and the number of strokes had increased 3.5 times. The investigators used data from both the randomized aspirin period and the observational period following the trial to assess the impact of aspirin use on cardiovascular and total mortality, and the long-term impact of aspirin use on subsequent stroke and MI. The methods included analyses of both randomized aspirin assignment and of time-varying aspirin use, as assessed on the annual questionnaires. Because of the potential for bias, the propensity for aspirin use, particularly during the observational period was taken into account. Analyses included use of proportional hazards models allowing for both time-varying effects of aspirin use and controlling for time-varying confounders, as well as more complex procedures using causal modeling.

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

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Study Type : Observational
Study Start Date : April 1998
Actual Study Completion Date : March 2001

Information from the National Library of Medicine

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Ages Eligible for Study:   up to 100 Years   (Child, Adult, Older Adult)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   No
No eligibility criteria

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00005493

Sponsors and Collaborators
National Heart, Lung, and Blood Institute (NHLBI)
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OverallOfficial: Nancy Cook Brigham and Women's Hospital
Layout table for additonal information Identifier: NCT00005493    
Other Study ID Numbers: 5010
R03HL058476 ( U.S. NIH Grant/Contract )
First Posted: May 26, 2000    Key Record Dates
Last Update Posted: March 16, 2016
Last Verified: August 2004
Additional relevant MeSH terms:
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Cardiovascular Diseases
Heart Diseases
Myocardial Infarction
Coronary Disease
Pathologic Processes
Myocardial Ischemia
Vascular Diseases
Cerebrovascular Disorders
Brain Diseases
Central Nervous System Diseases
Nervous System Diseases