John Eikelboom

John Eikelboom

Associate Professor,  Department of Medicine, Hematology & Thromboembolism

Dr John Eikelboom is an Associate Professor in the Department of Medicine at McMaster University in Hamilton, Ontario. After earning his MBBS degree at the University of Western Australia Medical School, Australia, he completed training in Internal Medicine and Haematology at Royal Perth Hospital, Australia, and trained in Epidemiology and Thrombosis Medicine at McMaster University. He holds a Canada Research Chair in Cardiovascular Medicine from the Canadian Institutes for Health Research. Dr Eikelboom’s current research focuses on variable response to antiplatelet therapy, antithrombotic therapy in atrial fibrillation, and mechanisms and prognosis of bleeding. He has published more than 150 peer-reviewed papers. He is a member of the Editorial Board for Stroke and on the Advisory Board for the Journal of Thrombosis and Haemostasis.


Research Interests

Studying the mechanisms and genetic determinants of antiplatelet drug resistance and improving its diagnosis and treatment.

Research Relevance

The research is leading to the development of new diagnostic and therapeutic tools to prevent cardiovascular disease.

An Aspirin a Day . . . Overcoming the Problem of Aspirin Resistance in Patients with Cardiovascular Disease

Cardiovascular disease is the single most common cause of death or long-term disability in Canada and it costs the economy more than 18 billion dollars each year. Aspirin is a simple, safe, and highly cost-effective treatment to prevent cardiovascular disease and is the single most widely used pharmaceutical agent worldwide.

Not all patients at risk of cardiovascular disease, however, benefit from aspirin. One in seven patients experiences another heart attack or stroke or will die from the complications of cardiovascular disease within two to three years of starting treatment.

The challenge for clinicians and researchers is to determine why this occurs and what can be done to prevent breakthrough cardiovascular events in patients already treated with aspirin.

This is where Dr. John Eikelboom comes in. In a landmark study involving almost 1,000 patients at high risk of cardiovascular events treated with aspirin, Dr. Eikelboom and his colleagues demonstrated that at least 20 percent of heart attacks, strokes, and deaths that occur during aspirin treatment are caused by a “resistance” to its antiplatelet effects. What’s more, evidence suggests that patients who are resistant to aspirin may be identified by a simple urine test.

Identifying those patients who are most likely to be resistant to aspirin is but the first step in solving the problem of aspirin resistance. As a Canada Research Chair in Cardiovascular Medicine, Dr. Eikelboom is figuring out what causes aspirin resistance and he is working on the development of new treatments to overcome the problem.

Dr. Eikelboom’s work has implications for clinical and public health worldwide. Because of the scope of cardiovascular disease and the widespread use of aspirin, even a small improvement in its effectiveness could prevent thousands of heart attacks and strokes each year.

Significant Contributions (Studies)

  1. Prevalence, Mechanisms, and Management of Variable Response to Antiplatelet Therapy.

  2. Prognostic Importance of Bleeding in Patients with Acute Coronary Syndromes.

  3. Systematic Reviews of Antithrombotic Therapy in Venous and Arterial Thrombosis.

  4. Causative and Prognostic Factors in Ischaemic Stroke and Etiologic Subtypes of Ischaemic Stroke.

  5. Folate-based Multivitamin Therapy to Prevent Stroke.

Lab Profiles

Nima Vaezzadeh, PhD Candidate
Ran Ni, PhD Candidate
Shana Aadl Shaya, MSc Candidate

Lab Profiles

Kim Nagel, Clinical Research Coordinator
Helen Atkinson, Research Assistant
Netnapha Paredes, Research Assistant
Laura Calvert, MSc Candidate
Gabriela Chang, MSc Candidate
Sajjad Afraz, MSc Candidate