In total, 73 Chinese children newly diagnosed with T1DM (41 boys and 32 girls, mean age 7.6 ± 3.3 years, range 3–14 years) were followed-up for one year and analyzed. Their general characteristics are reported in Table 1. These parameters did not show any significant changes between the first and final measurements at the 12-month time point. One girl was lost to follow-up. At the onset, hypothyroidism were 6.2% and hyperthyroidism were 18.3%.(Table 2) After 12 months, Hypothyroidism were 4.1% and hyperthyroidism were 6.1%. Detection rates for GADAb, IAA, ICA, TPOAb, and TRAb were 31.8%, 22.7%, 0%, 35.29%, and 5.89%, respectively. The HbA1c ≥ 7.5% group accounted for 13.69%, and the HbA1c < 7.5% group accounted for 86.31%. There were no differences in the prevalence of autoantibodies (GADAb, ICA, IAA, TRAb, and TPOAb) in pre- and post-study subjects. There was overlap between GAD + children and IAA + children. In GAD + cases, TPOAb accounted for 55.6%. In GAD- cases, TPOAb accounted for 17.2% of cases. There were no differences in fasting plasma glucose, C-peptide, HbA1c, insulin dose, FT3, FT4, or TSH between boys and girls with T1DM. Further, there were no differences in the proportion of boys and girls, or between pre-pubertal and post-pubertal subjects who were autoantibody positive (specifically, GADAb, ICA, IAA, TRAb, and TPOAb). However, there was a difference in FT3 observed between the HbA1c ≥ 7.5% and HbA1c < 7.5% groups (4.60 ± 1.37 pmol/L vs. 6.64 ± 0.30 pmol/L). There were no differences in FT4, TSH, or TPOAb between the HbA1c ≥ 7.5% and HbA1c < 7.5% groups.
Table 1
Serial changes in the parameters of a single group.
|
Onset
|
After 12 months
|
Boys(n)
|
41
|
41
|
Girls(n)
|
32
|
31
|
Age(years)
|
7.6 ± 3.3
|
8 ± 2.5
|
Height(cm)
|
127.67 ± 20.1
|
129.05 ± 17.25
|
Weight(kg)
|
29.04 ± 11.22
|
30.5 ± 14.26
|
BMI
|
17.15 ± 2.47
|
17.38 ± 2.45
|
FPG(mmol/L)
|
8.04 ± 3.71
|
7.91 ± 2.51
|
HbA1c (%)
|
8.66 ± 2.10
|
8.00 ± 1.49
|
C peptide(ng/ml)
|
0.22 ± 0.24
|
0.21 ± 0.10
|
ALP(U/L)
|
176.3 ± 28.5
|
191.3 ± 31.5
|
Creatinine(umol/L)
|
37.4 ± 4.2
|
35.9 ± 5.6
|
AST(U/L)
|
29 ± 2.2
|
27 ± 2.4
|
ALT(U/L)
|
16 ± 1.9
|
14 ± 2.1
|
Urea nitrogen(umol/L)
|
4.7 ± 0.25
|
5.1 ± 0.16
|
Values are expressed as mean ± SD. *P < 0.05 vs. corresponding control values. |
Table 2
The general characteristic of three groups.
|
Hyperthyroidism
|
Euthyroid
|
Hypothyroidism
|
TRAb (IU/L)
|
27.96 ± 0.76*
|
0.18 ± 0.75
|
0
|
TPOAb (IU/ml)
|
514.8 ± 101.24*
|
41.85 ± 51.24
|
15.95 ± 22.55
|
FT3 (pmol/L)
|
9.24 ± 1.16*
|
4.7555 ± 1.12
|
2.57 ± 1.93
|
FT4 (pmol/L)
|
27.8 ± 1.22*
|
16.37 ± 3.34
|
12.7 ± 8.95
|
TSH (uIU/L)
|
0.006 ± 1.09*
|
3.21 ± 4.27
|
3.21 ± 2.04
|
Values are expressed as the mean ± SD. Statistically significant differences are shown in *. *P < 0.05 vs corresponding control values. |
In the hyperthyroid group, mean concentrations of TRAb and TPOAb were significantly higher compared with the euthyroid group (27.96 U/L vs. 0.18 U/L and 514.0 IU/ml vs. 41.86 IU/ml, respectively; P < 0.001). In contrast, HbA1c was not different (Fig. 1A). FT3 and FT4 were also higher in hyperthyroid than euthyroid subjects (Fig. 1B). Further, FT4, TSH, TRAb, and TPOAb concentrations were similar in the hypothyroid and euthyroid groups (Fig. 1C), although serum FT3 was significantly higher in the euthyroid group than hypothyroid group (Fig. 1D). Levels of TPOAb were mildly elevated in the euthyroid group. No differences in serum C-peptide, HbA1c, or insulin dose were observed between the hypothyroid and euthyroid groups (0.26 ng/ml vs. 0.62 ng/ml, 9.2% vs. 11.4%, and 0.49u/kg vs. 0.54 u/kg, respectively).
Levels of C-peptide and HbA1c did not differ between the start and end of the study (Fig. 1E), nor did the levels of FT3, FT4, and TSH (Fig. 1F). Next, we chose TPOAb + children and compared changes of thyroid function over a year. FT3, FT4, and TSH showed no differences between onset and 12 months of admission (4.43 ± 1.29 pmol/L vs. 6.06 ± 0.34 pmol/L, 15.95 ± 2.87 pmol/L vs.16.68 ± 1.66 pmol/L, and 3.80 ± 2.52 mIU/ml vs. 3.66 ± 2.37 mIU/ml, respectively).
As expected, presence of TRAb were associated with TPOAb by univariate analysis (r = 0.61, P = 0.00). FT4 was associated with presence of TRAb and HbA1c concentration (r = 0.51, P = 0.002 and r = − 0.32, P = 0.04, respectively). Additionally, FT3 remained associated with FT4, presence of TRAb and TPOAb, and HbA1c concentration by linear regression analysis (r = 0.69, P = 0; r = 0.43, P = 0.01; r = 0.54, P = 0.001; and r = − 0.35, P = 0.025, respectively). The presence of GADAb was also associated with TSH concentration (r = 0.31, P = 0.046).