Vascular Cell Adhesion Molecule-l (VCAM-l) in Graves' Disease: Its Association to Thyroid Status and Thyroid Receptor Stimulating Antibodies

• Main Authors: Wan Nazaimoon, W.M., Ismail, I.S., Tan, H.J., Kamaruddin, N.A., Khalid, A.K.
• Format: Article
• Language: English
• Published: 2004
• Subjects: R Medicine
• Online Access: http://eprints.um.edu.my/7227/1/Vascular_cell_adhesion_molecule.pdf; http://eprints.um.edu.my/7227/

Soluble vascular cell adhesion molecule-1 (sVCAM-1) and intercellular adhesion molecule-1 (sICAM-1) have been shown to be elevated in patients with Graves� disease and may play significant roles in the pathogenesis of the disease. The objective of this study was to measure the levels of sVCAM-1, sICAM-1, IL-6 and thyroid receptor stimulating antibodies (TRAb) in a cohort of hyperthyroid patients and determine their associations to thyroid hormones status, before and after 3 months therapy with carbimazole. Materials and Methods: Patients were given fixed daily dose of 20 mg carbimazole for 3 months and blood samples were collected at baseline and end of the study. Thirty eight patients were recruited from the Endocrine Clinic, Hospital University Kebangsaan Malaysia, con-sisting of 26 females and 12 males, age ranging from 16 to 65 years. Blood samples collected be-fore and at end of study were analyzed for TSH, Free T3, Free T4, thyroid receptor stimulating anti-bodies (TRAb), sVCAM-1, sICAM-1 and IL-6. Results: TRAb level of ?10 U/L was taken to be negative, while TRAb level of >10 U/L was considered as positive. Twenty-six patients (68) were TRAb positive (TRAb+) and 12 patients (30) were TRAb negative (TRAb-). Median TRAb in TRAb+ patients was 23 U/L at baseline, declining to 16.7 U/L (p<0.001) in the third 3 month. Serum sVCAM-1 levels were signifi-cantly elevated in TRAb+ patients compared to TRAb- (860 versus 499 ng/mL, p<0.001). The level decreased significantly to 537 ng/mL with treat-ment but remained higher than in TRAb- patients (p=0.003). Irrespective of TRAb status, all but one patient had elevated serum sICAM-1 levels that remained unaffected by carbimazole therapy. In contrast, IL-6 levels of hyperthyroid patients were within the reference range of 1.4-14.1 pg/mL. Baseline and post-treatment sVCAM-1, and not TRAb levels, were significantly corre-lated to thyroid hormones. Conclusion: Compared to other inflammatory markers, sVCAM-1 showed significant correlation to thyroid stimulating antibodies and was most sensitive to changes in thyroid status. The significance of these findings in relation to Graves� disease warrants further investigation.