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Observational Aspirin Use and CVD in the Physicians' Health Study

This study has been completed.
Information provided by:
National Heart, Lung, and Blood Institute (NHLBI) Identifier:
First received: May 25, 2000
Last updated: March 15, 2016
Last verified: August 2004
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.

Cardiovascular Diseases
Coronary Disease
Heart Diseases
Myocardial Infarction
Cerebrovascular Accident

Study Type: Observational

Further study details as provided by National Heart, Lung, and Blood Institute (NHLBI):

Study Start Date: April 1998
Study Completion Date: March 2001
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.


Ages Eligible for Study:   up to 100 Years   (Child, Adult, Senior)
Genders Eligible for Study:   Male
Accepts Healthy Volunteers:   No
No eligibility criteria
  Contacts and Locations
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Please refer to this study by its identifier: NCT00005493

Sponsors and Collaborators
National Heart, Lung, and Blood Institute (NHLBI)
OverallOfficial: Nancy Cook Brigham and Women's Hospital
  More Information

Publications: Identifier: NCT00005493     History of Changes
Other Study ID Numbers: 5010  R03HL058476 
Study First Received: May 25, 2000
Last Updated: March 15, 2016
Health Authority: United States: Federal Government

Additional relevant MeSH terms:
Cardiovascular Diseases
Heart Diseases
Myocardial Infarction
Coronary Disease
Coronary Artery Disease
Pathologic Processes
Myocardial Ischemia
Vascular Diseases
Arterial Occlusive Diseases
Cerebrovascular Disorders
Brain Diseases
Central Nervous System Diseases
Nervous System Diseases processed this record on October 21, 2016