Association of thyroid function with white coat hypertension and sustained hypertension

Abstract

This study aimed to explore the relationship of thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxine (FT4) levels with hypertension subtypes. 1056 euthyroid adults were included as research samples. They underwent measurement of clinic blood pressure and 24-hours ambulatory blood pressure monitoring. Then, they were divided into normotension (NT), white coat hypertension (WCH), masked hypertension (MHT), and sustained hypertension (SHT) groups. The 24-hours dynamic electrocardiogram was performed to analyze the heart rate variability (HRV), so as to reflect the cardiac autonomic function. The relationship between hypertension subtypes, thyroid function, and HRV was analyzed. The TSH concentration was significantly higher in the SHT group than in the NT group (P = 0.001). The FT3 concentration was higher in the SHT group than in the NT and MHT groups (P = 0.013, P = 0.008), while the FT4 concentration was significantly higher in the WCH group than in the NT group (P = 0.002). The changes in HRV were observed between the SHT, WCH, and MHT groups and the NT groups, as well as between the SHT and the MHT groups. The multiple linear regression analysis also showed that FT3, HRV (RMSSD and PNN50), and blood pressure levels linearly correlated with one another (P < 0.05). Meanwhile, the linear regression analysis showed a linear negative correlation between FT4 and HRV (SDANN) in the WCH + NT group (P = 0.001). Thyroid function was closely related to hypertension subtypes such as WCH probably due to the changes in the cardiac autonomic function. | 675 CAI et Al.

Diagnostic performance of clinic and home blood pressure measurements compared with ambulatory blood pressure: a systematic review and meta-analysis

“…Among the studies that reported 2 × 2 data (n = 66,767), 29 studies [ 9 , 11 , 20 – 34 , 40 , 58 – 63 , 66 , 72 – 74 ] used a CBPM cutoff threshold as ≥ 140/90 for diagnosis of HT, while one study [ 19 ] used the threshold of DBP > 95 mmHg and one study did not reported the threshold. The 24-h ABPM had a cut-off of ≥ 130/80 mmHg for 12 studies [ 11 , 26 , 31 – 33 , 58 , 59 , 61 – 63 , 74 ] and daytime ABPM had a cut-off of ≥ 135/85 mmHg for 16 studies [ 20 – 25 , 28 – 30 , 34 , 60 , 65 , 66 , 73 ]. Two [ 27 , 72 ] and one [ 19 ] studies applied daytime ABPM with cut-offs of ≥ 140/85 and DBP ≥ 95 mmHg, respectively (see Additional file 1 : Table 2).…”

Blood pressure characteristics of subclinical hypothyroidism: an observation study combined with office blood pressure and 24-h ambulatory blood pressure

“…These pathological changes may cause the body's blood pressure to rise; however, many clinical studies have not found that subclinical hypothyroidism is related to office blood pressure [ 29 ]. In our previous studies, we have found that white-coat hypertension, masked hypertension, and sustained hypertension have their own thyroid function characteristics in the euthyroid participants [ 13 ]. For example, among patients with euthyroid, elevated TSH was only found in those with sustained hypertension.…”

“…The division method was based on the standards of our laboratory. The thyroid function standard of S-HYPO group was TSH greater than 5.60 uIU/ml; FT3, 3.09–7.42 pmol/l; FT4, 7.64–16.03 pmol/l, and the thyroid function in euthyroid group was TSH, 0.34–5.60 uIU/ml; FT3, 3.09–7.42 pmol/l; FT4, 7.64–16.03 pmol/l [ 13 ].…”

Effects of white-coat, masked and sustained hypertension on coronary artery stenosis and cardiac arrhythmia

“…Faria Joao et al did not find an increased incidence of cardiovascular events in patients with nocturnal NT WCHT during a 7.6-year follow-up study [ 39 ]. However, abnormal glucose and lipid metabolism and cardiac structural changes in nocturnal normal WCHT have also been reported in many studies [ 12 , 40 ]. Whether WCHT also causes cardiovascular damage remains controversial.…”