Ambulatory arterial blood pressure monitoring in patients before and after thyroidectomy

Bacground/Aim. Increased values of thyroid hormones in the clinical syndrome of hyperthyreosis affect blood pressure values and its circadial variation. The aim of this study was to define the influence of hyperthyreosis on the values and circadial variations of arterial blood pressure, as well as to investigate the effect of thyroid surgery on blood pressure values. Methods. We compared the 24-hour averages of systolic and diastolic blood pressure, their variations and their reduction during the night between 20 female patients with hyperthyroidism and hypertension de novo and 20 healthy females. We compared the values of 24-hour ambulatory monitoring performed before the surgery with the values gathered two weeks after the surgery. Results. The 24-hour average systolic and diastolic blood pressure values were higher in the patients with hyperthyroidism than in the control group (p < 0.001). In the group of patients, the variations in blood pressure were significantly higher than they were in the group of healthy people (p < 0.001). The amplitude of the nocturnal reduction of blood pressure was also significantly lower in the patients with hyperthyroid status and hypertension, in comparison to the healthy persons (p < 0.001). Two weeks after the surgery, a significant reduction of blood pressure values (both for systolic and diastolic) appeared. Conclusion. The patients with hyperthyroidism- caused hypertension had higher systolic and diastolic blood pressure, higher variations in blood pressure and lower nocturnal reduction of blood pressure than healthy subjects. Thyroid surgery, as a control of thyroid function, optimised blood pressure very rapidly.