Diastolic Hypertension in Hypothyroidism: Mechanism
Hypothyroidism has been recognized as a cause of secondary hypertension.
Previous studies on the prevalence of hypertension in subjects with hypothyroidism have demonstrated elevated diastolic blood pressure values. (hypertension in ~30% of patients)
In hypothyroidism, there is endothelial dysfunction and arterial smooth muscle compliance is reduced => leads to increased Systemic Vascular Resistance (SVR).
This appears to be a multi-factorial mechanism (increased adrenergic activity and reduction in endothelial-derived relaxation factor (EDRF) availability).
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