Significance of thyroid blood flow as a predictor of methimazole sensitivity in untreated hyperthyroid patients with Graves' disease.
OBJECTIVE
The peak systolic velocity (PSV) of the inferior thyroid artery (ITA) is increased in untreated hyperthyroid patients with Graves' disease (GD). We investigated the clinical significance of the ITA-PSV and its determinants in hyperthyroid GD patients.


METHODS
ITA-PSV, together with thyroid volume, was measured by ultrasonography in untreated hyperthyroid GD patients (n=49) and healthy subjects (n=22). Established markers of GD activity such as TSH receptor antibody (TRAb), thyroid stimulating antibody (TSAb), vascular endothelial growth factor (VEGF) and immunoglobulin E (IgE) were simultaneously determined.


RESULTS
ITA-PSV, thyroid volume, VEGF and IgE were significantly higher in hyperthyroid GD patients than in normal subjects. ITA-PSV in hyperthyroid GD patients was correlated positively with serum levels of FT(3), FT(4) and IgE, smoking index and thyroid volume, and negatively with total, HDL- and LDL-cholesterols, but did not correlate significantly with age, triglyceride, TRAb, TSAb or VEGF. In stepwise regression analysis, ITA-PSV showed significant positive and negative associations with IgE and LDL-cholesterol, respectively, in hyperthyroid GD patients. In the pre-treatment hyperthyroid state, FT(4) and ITA-PSV, but not IgE, were found to be significantly and positively associated with the maintenance dose of methimazole (MMI) required to keep serum TSH within normal range for at least 12 months.


CONCLUSIONS
These results suggest that ITA-PSV in untreated hyperthyroid GD patients may reflect GD activity and thus MMI sensitivity.
Nagasaki
Toshiki
T
Department of Metabolism, Endocrinology and Molecular Medicine, Osaka City University Graduate School of Medicine, 1-4-3, Asahi-machi, Abeno-ku, Osaka 545-8585, Japan.
Inaba
Masaaki
M
Kumeda
Yasuro
Y
Fujiwara-Ueda
Misako
M
Hiura
Yoshikazu
Y
Nishizawa
Yoshiki
Y
D000293:Adolescent; D000328:Adult; D000368:Aged; D013956:Antithyroid Agents / Q000627:therapeutic use*; D001783:Blood Flow Velocity; D005260:Female; D006111:Graves Disease / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000503:physiopathology; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D018828:Immunoglobulins, Thyroid-Stimulating / Q000097:blood; D008297:Male; D008713:Methimazole / Q000627:therapeutic use*; D008875:Middle Aged; D011237:Predictive Value of Tests; D011989:Receptors, Thyrotropin / Q000276:immunology; D012039:Regional Blood Flow; D013961:Thyroid Gland / Q000098:blood supply* / Q000000981:diagnostic imaging / Q000473:pathology; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood; D018608:Ultrasonography, Doppler; D042461:Vascular Endothelial Growth Factor A / Q000097:blood
D013956:Antithyroid Agents; D018828:Immunoglobulins, Thyroid-Stimulating; D011989:Receptors, Thyrotropin; D042461:Vascular Endothelial Growth Factor A; D014284:Triiodothyronine; D007073:Immunoglobulin E; D008713:Methimazole; D013974:Thyroxine