Table 2. Biochemical characteristics of the study population.

	IFG (n = 23)	IGT (n = 277)	IFSG (n = 57)	NGT (n = 355)	P
Fasting leptin (ng/mL)	34.35* (26.54–56.48)	25.86 (16.24–38.24)	31.30 (21.07–49.43)	26.31 (17.99–37.87)	0.005
Fasting insulin (μU/mL)	9.53* (7.66–11.47)	7.43 (5.66–9.50)	10.46* (7.87–13.14)	6.87 (5.51–8.42)	<0.001
HOMA-IR	2.18* (1.75–2.62)	1.49 (1.08–1.89)	2.52* (1.95–3.33)	1.30 (1.02–1.63)	<0.001
QUICKI	0.26* (0.25–0.27)	0.28 (0.27–0.31)	0.25* (0.23–0.26)	0.30 (0.28–0.32)	<0.001

IFG: impaired fasting glucose; IGT: impaired glucose tolerant; IFSG: impaired fasting and stimulated plasma glucose; NGT: normal glucose tolerance; HOMA-IR: homeostasis model assessment-insulin resistance; QUICKI: quantitative insulin sensitivity check index.

^†P was calculated using Kruskal-Wallis test and the multiple comparison was conducted by Dunnett-t test.

^*The difference was significant when compared with NGT group.