A high normal thyroid-stimulating hormone is associated with arterial stiffness, central systolic blood pressure, and 24-hour systolic blood pressure in males with treatment-naïve hypertension and euthyroid.

Background: We compared the results of laboratory examinations, echocardiography, arterial stiffness, central blood pressure (BP) and ambulatory BP monitoring (ABPM) between treatment-naïve patients with low normal thyroid-stimulating hormone (TSH) and those with high normal TSH levels.

Methods: A total of 285 consecutively-eligible patients with both treatment-naïve hypertension and euthyroid were divided into two groups: those with low-normal TSH (0.40-1.99 μIU/mL, group 1) and high-normal TSH (2.00-4.50 μIU/mL, group 2) and compared according to group and gender.

Results: Males were divided into group 1 (n = 113, 68.9%) and group 2 (n = 51, 31.1%) and females were divided into group 1 (n = 71, 58.7%) and group 2 (n = 50, 41.3%). Multivariate analyses revealed that the augmentation index (71.0 [adjusted mean] ± 1.7 [standard error] vs. 78.8 ± 2.5%, P = 0.045), central systolic BP (SBP) (143.3 ± 2.1 vs. 153.0 ± 3.2 mmHg, P = 0.013), systemic vascular resistance (SVR, 21.4 ± 0.6 vs. 23.9 ± 0.9 mmHg/L/min, P = 0.027), SBP during daytime (144.1 ± 1.4 vs. 151.6 ± 2.1 mmHg, P=0.004) and nighttime (130.4 ± 1.6 vs. 138.5 ± 2.5 mmHg, P=0.008), and nighttime pulse pressure (PP, 47.2 ± 0.9 vs. 51.7 ± 1.4 mmHg, P = 0.010) were significantly higher while cardiac output (5.4 ± 0.1 vs. 4.8 ± 0.2L/min, P = 0.043) and PP amplification (1.02 ± 0.02 vs. 0.94 ± 0.03, P = 0.039) were significantly lower in the male group 2 than in the male group 1. However, there were no significant differences between the two groups in females.

Conclusions: Treatment-naïve hypertensive males with high normal TSH and euthyroid showed higher arterial stiffness, central SBP, SVR, and SBP in ABPM and lower cardiac output and PP amplification as compared to the the low normal TSH group, but not females.