Increased pulse wave velocity in subclinical hypothyroidism.
OBJECTIVE
Subclinical hypothyroidism affects 5-15% of the general population and is associated with increased morbidity from cardiovascular disease. Brachial-ankle pulse wave velocity (baPWV) is a parameter of arterial stiffening and a good independent predictor for the presence of coronary artery disease. This study was performed to assess whether subclinical hypothyroidism might cause enhanced baPWV.


METHODS
baPWV was examined in subclinical hypothyroid patients (n = 50) and normal control subjects (n = 50).


RESULTS
Diastolic blood pressure (DBP), a main risk factor for cardiovascular disease, and baPWV were both significantly higher in subclinical hypothyroid patients than normal subjects. baPWV was significantly positively correlated with age and systolic, diastolic, and pulse pressure and significantly negatively correlated with pulse rate in both subclinical hypothyroid patients and normal subjects. In contrast, there was no significant correlation of baPWV with free T3, free T4, TSH, total, high-density lipoprotein- and low-density lipoprotein-cholesterol, and the preejection time to ejection time ratio. A comparison of individual values of baPWV and DBP and regression slopes in two groups revealed that baPWV values increase to a larger extent than the increase in DBP in subclinical hypothyroid patients. In both groups, stepwise regression analysis showed a significant and independent association of DBP with baPWV.


CONCLUSIONS
The present study demonstrated significant increases of baPWV and DBP in subclinical hypothyroid patients. Furthermore, the results suggest that increased DBP might be one of the main factors responsible for increased arterial stiffening in subclinical hypothyroid patients.
Nagasaki
Toshiki
T
Department of Metabolism, Endocrinology, and Molecular Medicine, Internal Medicine, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan.
Inaba
Masaaki
M
Kumeda
Yasuro
Y
Hiura
Yoshikazu
Y
Shirakawa
Kumi
K
Yamada
Shinsuke
S
Henmi
Yasuko
Y
Ishimura
Eiji
E
Nishizawa
Yoshiki
Y
D000368:Aged; D001158:Arteries / Q000503:physiopathology*; D001794:Blood Pressure; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000503:physiopathology; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000097:blood / Q000150:complications / Q000503:physiopathology*; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D012044:Regression Analysis; D015203:Reproducibility of Results; D012307:Risk Factors; D013318:Stroke Volume / Q000502:physiology; D013963:Thyroid Hormones / Q000097:blood; D016277:Ventricular Function, Left / Q000502:physiology
D008055:Lipids; D013963:Thyroid Hormones