Table 1.
Comparison of clinical and biochemical parameters in the five subgroups.
| At diagnosis | Hyperthyroidism | Euthyroidism | SCH | Compensated SCH | Hypothyroidism | P-value |
|---|---|---|---|---|---|---|
| Hormonal status | TSH <0.03 mIU/L FT4 > 20 pmol/L | TSH 0.4–4.2 mIU/L FT4 10–20 pmol/L |
TSH 4.3–10 mIU/L | TSH 10.1–20 mIU/L | TSH > 20 mIU/L | |
| No. of patients | 7 (3.7%) | 27 (14.3%) | 60 (32%) | 30 (16%) | 64 (34%) | |
| Gender (F:M) % male | 6:1 (14%) | 25:2 (8%) | 43:17 (28%) | 22:8 (27%) | 57:7 (11%) | |
| At presentation | ||||||
| Age (years) | 13.8 ± 2.6 (8.2–16.2) |
13.2 ± 3.0 (7.7–17.8) |
11.5 ± 2.9 (5.2–17.5) |
12.0 ± 3.8 (4.5–17.6) |
10.6 ± 3.4 (2.3–17.6) |
0.005 |
| TSH (mIU/L) | 0.03 ± 0.01 (0.02–0.04) |
2.4 ± 1.0 (0.9–4.1) |
7.1 ± 1.7 (4.4–9.8) |
13.5 ± 3.0 (10.1–19.6) |
152.1 ± 226 (21.7–1224.7) |
<0.0001 |
| FT4 (pmol/L) | 34.5 ± 16.1 (19.6–67.0) |
14.8 ± 2.2 (11.3–19.2) |
14.1 ± 2.3 (9.4–19.8) |
13.3 ± 1.7 (10.3–17.1) |
7.8 ± 3.1 (1.2–14.2) |
<0.0001 |
| TPOAb (U/mL) | 681 ± 448 (65–1,000) |
397 ± 321 (26–1,000) |
721 ± 1005 (10–5,730) |
645 ± 397 (35–1,000) |
1,195 ± 2,010 (11–13,372) |
0.01 |
| TGAb (U/mL) | 357 ± 408 (30–1,136) |
451 ± 723 (28–3,000) |
485 ± 868 (20–3,000) |
529 ± 1,092 (25–4,284) |
876 ± 1,463 (30–6,500) |
0.5 |
| At LT4 therapy initiation | ||||||
| Age (years) | 17.4 ± 4.5 (12.5–23.3) |
14.8 ± 3.9 (9.2–22.4) |
13.5 ± 3.7 (6.0–21.8) |
12.8 ± 4.5 (5.0–23.3) |
10.6 ± 3.4 (2.3–17.8) |
0.0001 |
| Years between diagnosis and LT4 therapy | 4.4 ± 3.6 (1.07–9.5) |
2.7 ± 2.1 (0–8.1) |
1.4 ± 2.2 (0–11.3) |
0.27 ± 1.3 (0–12.4) |
0.05 ± 0.271 (0–2.17) |
<0.0001 |
| TSH at LT4 initiation (mIU/L) |
47.6 ± 69 (6.4–150.6) |
36.0 ± 49.2 (0.9–132) |
17.2 ± 28.0 (5.0–150.4) |
21.9 ± 29.1 (5.5–150) |
153.1 ± 2,283 (5.3–1,223) |
<0.0001 |
| FT4 at LT4 initiation (pmol/L) | 10.4 ± 6.9 (6.9–14.4) |
11.4 ± 4.3 (3.4–16.4) |
13.2 ± 2.4 (8.8–19.8) |
13.0 ± 2.7 (4.4–17.8) |
7.7 ± 3.1 (1.2–13.7) |
<0.0001 |
| Time of study | ||||||
| Age (years) | 21.6 ± 6.7 (15–33) |
19.5 ± 6.3 (8.1–31.1) |
18.7 ± 5.5 (9.4–31.0) |
20.0 ± 5.9 (9.3–35.0) |
18.9 ± 5.8 (5.1–33.0) |
0.76 |
| Follow-up duration (years) | 8.0 ± 6.5 (0.4–19) |
6.4 ± 6.1 (0–20.8) |
7.6 ± 6.1 (0–20.8) |
8.7 ± 6.7 (0.1–29.4) |
9.3 ± 5.5 (0.8–22.0) |
0.11 |
| TSH (mIU/L) | 5.2 ± 4.3 (0.02–11.6) |
3.4 ± 3.4 (0.36–18.6) |
6.4 ± 3.4 (0.4–18.6) |
15.1 ± 53.3 (0.3–296) |
13.1 ± 31.8 (0.04–196) |
0.15 |
| FT4 (pmol/L) | 14.9 ± 8.4 (12.3–28.4) |
14.9 ± 9.9 (9.9–19.9) |
14.9 ± 7.2 (9.9–19.9) |
15.7 ± 6.4 (11.4–21.1) |
14.9 ± 5.6 (2.2–28.4) |
0.9 |
| TGAb (U/mL) | 460 ±599 (34–1,255) |
411 ± 833 (30–3,000) |
540 ± 980 (20–3,000) |
1,655 ± 4,363 (39–15,907) |
443 ± 565 (21–3,000) |
0.58 |
| TPOAb (U/mL) | 515 ± 456 (76–1,000) |
390 ± 291 (24–1,000) |
692 ± 866 (11–1,000) |
632 ± 380 (29–1,300) |
552 ± 535 (10–3,000) |
0.59 |
| No of patients undergoing LT4 therapy at time of study (%) | 4 (57%) | 7 (26%) | 33 (56%) | 25 (83%) | 53 (84%) | <0.0001 |
TSH normal range 0.4–4.2 mIU/L.
FT4 normal range 10–20 pmol/L.
SCH, sub clinical hypothyroidism, TPOAb, TPO abs; TGAb, Thyroglobulin antibodies.