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Published on: April 6, 2017
The adhesiveness of human blood platelets and thyroid function.
Acta Medica Scandinavica
|January 1, 1975
Summary
Hypothyroidism is linked to coronary artery disease, yet heart attacks are rare in these patients. This study suggests low platelet adhesiveness in hypothyroidism may protect against heart attacks, normalizing with treatment.
Area of Science:
- Cardiology
- Endocrinology
- Hematology
Background:
- Hypothyroidism is associated with severe coronary atherosclerosis.
- Despite this, the incidence of angina pectoris and myocardial infarction is paradoxically low in untreated hypothyroidism.
- Thrombus formation is a key event in myocardial infarction, suggesting platelet function may be altered.
Purpose of the Study:
- To investigate the role of platelet adhesiveness in the paradoxical rarity of myocardial infarction in hypothyroidism.
- To evaluate changes in platelet adhesiveness before and after treatment in hypothyroid and thyrotoxic patients.
Main Methods:
- Platelet adhesiveness was measured in 9 hypothyroid and 16 thyrotoxic patients.
- Measurements were taken before and after thyroid hormone replacement therapy.
Main Results:
- Thyrotoxicosis showed significantly increased platelet adhesiveness, which normalized post-treatment.
- Hypothyroidism exhibited abnormally low platelet adhesiveness, increasing to normal levels after thyroid hormone replacement.
Conclusions:
- Altered platelet adhesiveness may explain the low incidence of myocardial infarction in hypothyroidism.
- Thyroid hormone replacement normalizes platelet adhesiveness in both hypothyroidism and thyrotoxicosis.
- Platelet function changes might be a crucial factor in myocardial infarction risk for patients with hypothyroidism and coronary artery disease.
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