Benefits of Long-Term Continuation of Low-Dose Methimazole Therapy in the Prevention of Recurrent Hyperthyroidism in Graves’ Hyperthyroid Patients: A Randomized Prospective Controlled Study
Table 1
Baseline clinical and biochemical characteristics of 173 Graves’ hyperthyroid patients who were randomly assigned to discontinue and continue low-dose methimazole therapy.
DISCONT-MMI (90 cases)
CONT-MMI (83 cases)
value
Female/male (cases)
77/13
70/13
0.823
Age at first diagnosis of hyperthyroidism (years)
39.9 ± 10.9
42.2 ± 14.9
0.260
Positive family history of hyperthyroidism in first-degree-relatives (cases/cases, %)
18/50, 16.7%
6/47, 12.8%
0.008
Positive history of smoking (cases/cases, %)
2/50, 4.0%
3/48, 6.3%
0.169
Goiter size at randomization∗: Grade 0–1/grade 2/grade 3 (cases)
55/33/2
44/38/1
0.443
Thyroid bruit at randomization (cases/cases, %)
7/90, 7.8%
5/83, 6.0%
0.650
Ophthalmopathy at randomization∗∗ (cases/cases, %)
12/90, 13.3%
21/83, 25.3%
0.045
Dermopathy at randomization (cases/cases, %)
0/90, 0%
1/83
0.296
Positive antithyroglobulin antibody at diagnosis (cases/cases, %)
7/56, 12.5%
2/48, 4.2%
0.132
Positive antithyroid peroxidase antibody at diagnosis (cases/cases, %)
15/56
14/48
0.787
Serum TT3 at first diagnosis of hyperthyroidism (ng/dL)
454.9 ± 192.5
452.8 ± 189.8
0.945
Serum TT4 at first diagnosis of hyperthyroidism (μg/dL)
20.1 ± 5.6
19.0 ± 5.4
0.226
Serum TT3/TT4 ratio at first diagnosis of hyperthyroidism
22.7 ± 8.2
24.6 ± 13.3
0.307
Serum TT3 (ng/dL) at randomization
108.6 ± 73.8
112.4 ± 62.5
0.716
Serum FT4 (ng/dL) at randomization
1.22 ± 0.24
1.26 ± 0.18
0.219
Serum TSH (mIU/L) at randomization
2.15 ± 1.47
2.26 ± 1.35
0.609
Duration of MMI therapy at randomization (months)
36.8 ± 20.5
31.6 ± 19.2
0.336
DISCONT-MMI and CONT-MMI denoted patients who were randomly assigned to discontinue and continue low-dose methimazole therapy, respectively. ∗Goiter size was assessed clinically by one investigator (R.L.) using the 1960 WHO palpation system [16]. ∗∗Ophthalmopathy was assessed by one investigator (R.L.) and patients with eye symptoms suggesting the presence of severe and active ophthalmopathy were not included.
