The relationship of epicardial fat thickness with carotid intima media thickness and endothelial function in subclinical and overt hypothyroidism
Dilek Yazici1, Hasan Aydin1, Beste Özben2, Ahmet Toprak2, Dilek Yavuz1, Ozlem Tarcin1, Seda Sancak1, Oguzhan Deyneli1 & Sema Akalin1
Hypothyroidism is associated with increased cardiovascular mortality. Epicardial fat thickness (EFT) has been found to be correlated with visceral fat accumulation and is thought to be a novel cardiovascular risk factor. The aim of this study was to determine EFT and its relationship with carotid intima media thickness (CIMT) and flow-mediated vasodilation (FMD) in subclinical and overt hypothyroid patients.
Ten patients with overt (Group H) (42.2±15.1 y; F/M:9/1) and 18 patients with subclinical hypothyroidism (Group SH) (34.7±10.3 y; F/M:16/1) and without any other systemic disease were included. 28 healthy volunteers were recruited as controls. EFT was determined by M-mode echocardiography and FMD and CIMT were evaluated by Doppler echocardiography. The study was approved by local Ethical Committee.
EFT, FMD and CIMT results and the comparisons between the groups are shown in the table. EFT was weakly correlated with CIMT (r=0.33; P=0.11) and FMD (r=−0.26; P=0.22). TSH was also weakly correlated with CIMT (r=0.33, P=0.11) and FMD (r=−0.38; P=0.06).
| ||GROUP H (n=10)||GROUP SH (n=18)||CONTROLS (n=27)||P |
|Epicardial fat thickness (mm)||4.42±2.41a||2.41±1.49||3.28±0.31||P<0.05|
|aP<0.05; bP=0.06; cP=0.05 compared to group SH|
Epicardial fat accumulation is greater in subclinical and overt hypothyroid patients than healthy controls. This finding is more prominent in overt hypothyroid patients. Although larger studies are needed to confirm this preliminary finding, EFT seems to be a promising marker for early atherosclerotic changes in this group of patients.