Subclinical Hypothyroidism and Functional Hemodynamics of the Heart

Abstract

Subclinical hyperthyroidism (SHyper), a laboratory decrease in thyroid-stimulating hormone levels with peripheral thyroid hormone levels within the reference interval, is considered a medical condition, especially its impact on cardiac hemodynamics among young women. To determine the effects of subclinical thyroid dysfunction on hemodynamics in young women. clinical observation included two groups of women: (1) the main group consisted of 30 patients with subclinical hyperthyroidism, which was examined at the Family Medicine Clinic of the West Kazakhstan Marat Ospanov Medical University (Aktobe, Kazakhstan) and (2) the control group consisted of 30 practically healthy women. The groups were comparable in age (30–42), mean age 36.2±7.0 years. Blood pressure (BP) was measured, heart rate (HR) was counted, and thyroid hormones were determined. in the examined patients, clinical symptoms of pathology were not observed; laboratory tests determined a decrease in thyroid-stimulating hormone (TSH) in the main group of patients to 2.48±0.23 mIU/L in comparison with the control group 3.65±1.3 mIU/L, which was significant (p0.05) increase in blood pressure SBP/DBP from 122.34±2.7/78.3±2.7 to 127.8±3.1/83.2±2.1 mmHg and HR from 77.7±1.9 to 82.2±2.6 in 1 minute. A significant (r2 =0.482) interaction was determined between TSH -0.236 mIU/L and HP +20.3 in 1 minute, this could be a predictor of an increase in heart rate greater than the reference value (60–80 per minute), and an increased heart rate is considered a predictor of an increase in blood pressure. Subclinical hyperthyroidism may produce a significant laboratory decrease in TSH, without significant clinical symptoms of increased blood pressure. In conclusion, current observational experience suggests that small decreases in laboratory values of thyroid-stimulating hormone may affect blood pressure and heart rate.

Keywords:

subclinical thyrotoxicosis, thyroid-stimulating hormone, thyroxine, blood pressure

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