No Correlations between TSH receptor antibody levels assayed with Elecsys TRAb and the activity or severity of Graves ophthalmopathy
J. Noh, K. Iwaku, M. Suzuki, K. Sekiya, M. Matsumoto, H. Ohye, Y. Kunii, A. Yoshihara, N. Watanabe, K. Mukasa, Y. Kosuga, K. Ito & K. Ito
Objective: This study was designed to determine whether TRAb levels are correlated with the activity and severity of Graves ophthalmopathy (GO).
Subjects and Methods: The subjects were 179 untreated Graves disease patients. TRAb was assayed with Elecsys TRAb at the initial visit, and an ophthalmic assessment was performed within 3 months. The activity of the ophthalmopathy was assessed by clinical activity scores (CASs) and MRI T2 relaxation times. Exophthalmos was measured with Hertels exophthalmometer, and the measurements in both eyes were summed (exophthalmos score). Eyelid swelling was evaluated by inspection, scored from 0 to 3 in each eye, and scores were summed (eyelid swelling score). Swelling of each extraocular muscle was evaluated, scored from 0 to 4 by MRI, and the scores were summed (extraocular muscle score).
Results: According to the activity of the ophthalmopathy the numbers of active, inactive, and recovery phase patients were 18, 152, and 1, respectively. CASs ranged from 0 to 3 points, and the numbers of patients with each CAS were 57, 76, 37, and 9, respectively. The median (range) TRAb level of the active phase patients and inactive phase patients was 6.55 IU/L (0.640.0) and 13.6 IU/L (0.340.0), respectively (P=0.0298). The TRAb levels of the patients whose CASs were 0 to 3 were 8.9 IU/L (0.340), 13.4 (0.340), 18.7 (140), and 16 (1.840), respectively, and there was no significant difference among them (Wilcoxon test, P=0.087).
TRAb levels did not correlate with exophthalmos scores (r=0.1133, P<0.131), eyelid swelling scores (r=0.1454, P=0.0521), or extraocular muscles scores (r=−0.0653 P<0.3879).
Conclusion: The TRAb levels were not correlated with either GO activity or severity.
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