The usable markers of atherosclerosis measured by Doppler Ultrasound of lower limb artery in treatment- naive hypothyroid females
Z. Gluvic1, J. Tica1, Z. Rasic-Milutinovic1, M. Vujovic1, V. Popovic-Radinovic1, M. Lackovic1 & E. Isenovic2
Background: It has been shown that hypothyroidism is associated with atherosclerosis. The presence of atherosclerosis process could be registered by use of some Doppler Ultrasound parameters (DUP) intima-media complex thickness (IMCT) and systolic velocity (SV). In this study we present initial DUP on the lower limb artery in treatment-naïve hypothyroid females and the influence of thyroid hormone levels and some metabolic components.
Methods and design: In this study 45 female patients were involved and divided into three groups regarding the thyroid hormone levels at the time of presentation: subclinical hypothyroid group, clinical hypothyroid group, and control euthyroid group. At the initial visit, some of metabolic components were measured: BMI, systolic and diastolic blood pressure, blood glucose and lipid levels. All patients were referred for DUP measurement on the proximal segment of right superficial femoral artery (RSFA). Data were statistically analyzed by using SPSS for Windows.
Results: An average IMCT and SV at presentation were 0.86±0.21 mm and 0.53±0.13 m/sec, respectively. The values obtained for SV were not differ between groups, while IMCT values were find to be different (F=8.212, P<0.01), with no contribution of difference between subclinical and clinical hypothyroid group. The patients average age (48±11 years) influenced significantly on IMCT (r=0.494, P<0.01). The overall initial average levels for TSH and fT4 were 7.21 mIU/L and 12.7±3.2 pmol/L and both hormones significantly influenced on IMCT (ρTSH=0.584; ρfT4=−0.41; P<0.05), but not on SV. The levels of triglycerides, glucose, cholesterol and its fractions ware not found to influence on IMCT.
Conclusion: This study clearly indicates that abnormal IMCT is a better marker of atherosclerosis in treatment of naïve hypothyroid patients than SV. Since TSH and fT4 levels may influence IMCT, both hormone levels should be used as the valid markers of serious atherosclerosis presence, in contrary to measured metabolic components.
Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.
Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector