Association between Cervical Lymph Node Metastasis and the Incidence of Radiation-Induced Hypothyroidism in Nasopharyngeal Carcinoma

Table 3

Multivariate analysis of radiation-induced HT.

Variables (ref)	Model 1			Model 2			Model 3
	Beta	OR (95% CI)		Beta	OR (95% CI)		Beta	OR (95% CI)
Constant	−1.08	0.34 (0.08–1.46)	0.146	0.83	2.30 (0.48–11.12)	0.300	−0.67	0.51 (0.05–4.89)	0.563
N stage	0.79	2.20 (1.12–4.33)	0.023
Pretreatment TSH	1.14	3.12 (2.07–4.72)	<0.001	1.23	3.41 (2.20–5.29)	<0.001	1.26	3.54 (2.25–5.57)	<0.001
Thyroid volume	−0.09	0.91 (0.85–0.98)	0.010	−0.08	0.92 (0.86–0.99)	0.018	−0.09	0.92 (0.85–0.99)	0.020
Shortest distance from thyroid				−0.62	0.54 (0.39–0.74)	<0.001	−0.56	0.57 (0.41–0.80)	0.001
Numbers of positive lymph nodes in IIb area
1–2 (ref: 0)							1.69	5.42 (1.40–20.97)	0.014
3+ (ref: 0)							0.79	2.19 (0.52–9.19)	0.282