NEW ORLEANS — Apparently healthy people with a family history of coronary artery disease who also had metabolic syndrome showed elevated platelet aggregation and reduced platelet responsiveness to aspirin in a study of more than 2,000 people.
These findings suggest that “low-dose aspirin therapy alone may not be sufficient to provide optimal antiplatelet protection” in people with metabolic syndrome and an increased risk for coronary artery disease, Dhananjay Vaidya, Ph.D., and his associates reported in a poster at the annual scientific sessions of the American Heart Association.
The link between metabolic syndrome and aspirin resistance in platelets was examined because metabolic syndrome is known to be proinflammatory and prothrombotic, they said.
The study involved 2,088 apparently healthy siblings, sibling offspring, and coparents of the sibling offspring of more than 500 patients younger than 60 years and hospitalized for coronary artery disease. The average age of the relatives was about 44 years, and about 58% were women. Overall, 28% of the group had metabolic syndrome.
The aggregability of each person's platelets was tested before and after 2 weeks of treatment with 81 mg/day of aspirin. Before starting aspirin, the plate-lets of the people with metabolic syndrome showed significantly more aggregation than the platelets from people without metabolic syndrome, after adjustment for age, gender, race, smoking status and baseline levels of LDL cholesterol and high sensitivity C-reactive protein, reported Dr. Vaidya, a vascular researcher in the department of medicine at Johns Hopkins University, Baltimore, and his associates.
Immediately after 2 weeks of daily aspirin treatment, the platelets of the people with metabolic syndrome continued to show a significantly higher level of aggregation, compared with platelets from those without metabolic syndrome, again after adjustment.
This finding has clinical implications because aspirin prophylaxis for coronary artery disease is recommended in people with metabolic syndrome, the researchers noted.