Diagnostic Values of Free Triiodothyronine and Free Thyroxine and the Ratio of Free Triiodothyronine to Free Thyroxine in Thyrotoxicosis

Table 1

Clinical characteristics of the study population.

	Healthy control	Untreated Graves’ disease	Painless thyroiditis	Subacute thyroiditis
Gender (M/F)	17/49	25/101	6/30	5/13
Age (years)	48.05 ± 14.72	40.25 ± 12.49	40.00 ± 12.79	43.94 ± 7.36
FT3 (pmol/L)	4.04 ± 0.50	24.85 ± 14.02^ab	6.36 ± 2.74	9.69 ± 4.88
FT4 (pmol/L)	12.87 ± 1.39	36.26 ± 14.09^ab	19.48 ± 5.64	30.49 ± 11.08
FT3/FT4 ratio	0.32 ± 0.04	0.66 ± 0.26^abc	0.32 ± 0.07	0.31 ± 0.07
TSH (mIU/L)	1.83 (0.54–3.25)	0.0006 (0.0001–0.01)^a	0.01 (0.0001–0.2927)	0.0046 (0.0001–0.39)
TPOAb (IU/L)	0.43 ± 0.59	444.33 ± 393.43^ac	336.45 ± 380.16	2.29 ± 3.59
TgAb (IU/L)	14.19 ± 87.19	221.29 ± 290.78^ac	207.87 ± 292.53	18.54 ± 31.78
TRAb (IU/L)	0.33 ± 0.08	15.51 ± 16.15^abc	0.60 ± 0.45	2.81 ± 8.71

Descriptive data were shown as mean ± SD for normally distributed continuous parameters, and for skewness distribution data, median and interquartile range was used. were considered statistically significant. Differences between multiple groups were tested by one-way analysis of variance (ANOVA) and post hoc comparisons were performed using Tukey’s tests. ^aSignificance difference between untreated GD and healthy control at . ^bSignificance difference between untreated GD and painless thyroiditis at . ^cSignificance difference between untreated GD and subacute thyroiditis at .