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Trial record 5 of 8380 for:    Physicians Health Study

Physicians' Health Study

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ClinicalTrials.gov Identifier: NCT00000500
Recruitment Status : Completed
First Posted : October 28, 1999
Last Update Posted : January 28, 2021
National Heart, Lung, and Blood Institute (NHLBI)
Information provided by (Responsible Party):
John Michael Gaziano, MD, Brigham and Women's Hospital

Brief Summary:
To assess the effect on cardiovascular mortality of alternate-day consumption of 325 milligrams of aspirin and, secondarily, the effect on cancer incidence of alternate-day consumption of 50 milligrams of beta-carotene.

Condition or disease Intervention/treatment Phase
Cardiovascular Diseases Coronary Disease Heart Diseases Myocardial Ischemia Drug: aspirin Drug: carotene Phase 3

Detailed Description:


Thrombosis plays a major role in the late stages of coronary occlusion. Platelet aggregation is a large component in the formation of arterial thrombi. In pharmacologic studies, aspirin has been shown to inhibit platelet aggregation and, therefore, might be expected to prevent coronary occlusion. These effects are apparent in the dose range of l00-l000 mg/day, and may be most evident at l60 milligrams daily. Higher doses seem to be no more effective in either inhibition of platelet agreeability or prolonged bleeding time.

Although an early case-control study by Jick and Miettinen showed a large benefit, most observational studies had shown a cardiovascular benefit of about 20 percent. Conclusive data could only result from a randomized trial with a large sample size.


Randomized, double-blind, fixed sample. Participants were randomized into one of four treatment groups: one 325 milligram aspirin tablet every other day, alternating with one 30 milligram capsule of beta-carotene; one aspirin every other day, alternating with one capsule of beta-carotene placebo; one aspirin placebo tablet every other day, alternating with one capsule of beta-carotene; and one aspirin placebo tablet every other day, alternating with one capsule of beta-carotene placebo. Major endpoints for the cardiovascular component of the study were cardiovascular mortality, total mortality, and coronary events.

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Study Type : Interventional  (Clinical Trial)
Allocation: Randomized
Masking: Double
Primary Purpose: Prevention
Study Start Date : September 1981
Actual Primary Completion Date : December 1995
Actual Study Completion Date : December 1996

Information from the National Library of Medicine

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Ages Eligible for Study:   40 Years to 84 Years   (Adult, Older Adult)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   No
Male physicians, ages 40 to 84. No history of stroke, myocardial infarction, cancer, or renal disease. No contraindications to aspirin or beta-carotene. No current usage of aspirin or Vitamin A tables greater than once per week.

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
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Responsible Party: John Michael Gaziano, MD, Chief, Division of Aging, Brigham and Women's Hospital
ClinicalTrials.gov Identifier: NCT00000500    
Other Study ID Numbers: 19
R01HL034595 ( U.S. NIH Grant/Contract )
First Posted: October 28, 1999    Key Record Dates
Last Update Posted: January 28, 2021
Last Verified: January 2021
Additional relevant MeSH terms:
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Cardiovascular Diseases
Heart Diseases
Coronary Disease
Myocardial Ischemia
Pathologic Processes
Vascular Diseases
Anti-Inflammatory Agents, Non-Steroidal
Analgesics, Non-Narcotic
Sensory System Agents
Peripheral Nervous System Agents
Physiological Effects of Drugs
Anti-Inflammatory Agents
Antirheumatic Agents
Fibrinolytic Agents
Fibrin Modulating Agents
Molecular Mechanisms of Pharmacological Action
Platelet Aggregation Inhibitors
Cyclooxygenase Inhibitors
Enzyme Inhibitors
Protective Agents