Effects of thyrotropin suppression on lumbar bone mineral density in postmenopausal women with differentiated thyroid carcinoma

Figures & data

Table 1 Patients’ clinical characteristics

	TSHS	Postmenopausal controls	t-value	P-value
Number	154	71
TSH (μlU/mL)	0.09±0.01	0.63±0.08	−10.57	0.00
Age (years)	55.58±8.1	55.94±8.09	−0.3	0.76
Height (cm)	161.4±5.83	161.44±5.43	−0.05	0.96
Weight (kg)	62.81±10.75	63.03±9.79	−0.14	0.89
Body mass index	23.51 ±3.54	23.17±4.02	0.6	0.55
FT3 (pmol/L)	6.30±2.09	4.46±1.23	8.36	0.00
FT4 (pmol/L)	22.24±7.14	17.35±3.15	7.16	0.00
Calcium (mmol/L)	2.24±0.15	2.21 ±0.17	1.26	0.21
Vitamin D 25	24.57± 17.79	25.56± 19.44	−0.14	0.89
BMD (g/cm^2)	1.05±0.16	1.06±1.21	−0.315	0.753

Note: Data are presented as mean ± SD unless otherwise specified.

Abbreviations: BMD, bone mineral density; FT3, triiodothyronine; FT4, free thyroxine; TSHS, thyroid-stimulating hormone suppression.

Table 2 BMD of the lumbar spine (g/cm²) in DTC patients with TSHS and postmenopausal controls

Follow-up	TSHS	Postmenopausal controls	t-value	P-value
Baseline	1.05±0.16	1.06±1.21	−0.315	0.753
6 months	1.03±0.17	0.98±0.16	1.37	0.17
12 months	1.04±0.14	1.04±0.17	−0.128	0.89
24 months	1.03±0.15	1.06±0.27	−0.547	0.59

Notes: TSHS and postmenopausal controls: baseline vs 6 months, t=1.209, P=0.228; t=2.018, P=0.05; baseline vs 12 months: t=0.602, P=0.55; t=0.42, P=0.67; baseline vs 24 months: t=0.97, P=0.33; t=0.004, P=0.997. Data are presented as mean ± SD.

Abbreviations: BMD, bone mineral density; DTC, differentiated thyroid carcinoma; TSHS, thyroid-stimulating hormone suppression.

Table 3 The number of osteopenia and osteoporosis in DTC patients with TSHS and postmenopausal controls during the 2-year follow-up

	Total	Number of osteopenia	Number of osteoporosis	χ^2	P-value
TSHS
Baseline	154	57	8
6 months	154	66	12	1.48	0.14
12 months	154	60	11	0.69	0.49
24 monthsa	152	90	13	4.3	<0.0001
Postmenopausal controls
Baseline	71	23	7
6 months	70	27	8	0.92	0.36
12 months	69	22	8	0.07	0.94
24 months	68	23	9	0.41	0.68

Notes:

a Significant difference in the number of osteopenia and osteoporosis patients at 24 months (χ²=2.88, P=0.004) between the TSHS and postmenopausal control groups; no significant difference in the number of osteopenia and osteoporosis patients at 6 and 12 months.

Abbreviations: DTC, differentiated thyroid carcinoma; TSHS, thyroid-stimulating hormone suppression.

Figure 1 Pearson analysis found that there was no significant correlation between BMD and FT3 (r=−0.054, P=0.437).

Abbreviations: BMD, bone mineral density; FT3, triiodothyronine.

Figure 2 Pearson analysis found that there was no significant correlation between BMD and FT4 (r=0.003, P=0.986).

Abbreviations: BMD, bone mineral density; FT4, free thyroxine.