Table 2.

Associations of plasma copper concentrations with IGR and T2D.

Variables	Tertiles of plasma copper concentration (μg/L)			P value for trend	Per SD of ln-transformed plasma copper	P value
	Q1	Q2	Q3
	<797.39 (709.25)a	797.39–956.13 (875.06)a	≥956.13 (1048.06)a
IGR vs. NGT
No. of cases/control subjects	131/335	145/335	236/334
Crude	1	1.11 (0.84–1.47)	1.81 (1.39–2.35)	<0.001	1.38 (1.25–1.54)	<0.001
Model 1b	1	1.19 (0.89–1.59)	1.99 (1.50–2.64)	<0.001	1.45 (1.29–1.62)	<0.001
Model 2c	1	1.20 (0.89–1.61)	1.88 (1.41–2.51)	<0.001	1.41 (1.26–1.58)	<0.001
Model 3d	1	1.13 (0.84–1.53)	1.74 (1.28–2.35)	<0.001	1.38 (1.22–1.55)	<0.001
T2D vs. NGT
No. of cases/control subjects	135/335	259/335	610/334
Crude	1	1.92 (1.48–2.48)	4.53 (3.56–5.76)	<0.001	2.00 (1.81–2.20)	<0.001
Model 1b	1	1.91 (1.47–2.50)	4.43 (3.44–5.70)	<0.001	2.00 (1.81–2.22)	<0.001
Model 2c	1	1.89 (1.43–2.50)	4.25 (3.27–5.53)	<0.001	1.97 (1.78–2.20)	<0.001
Model 3d	1	1.85 (1.39–2.45)	4.21 (3.20–5.55)	<0.001	2.04 (1.82–2.28)	<0.001
(IGR & T2D) vs. NGT
No. of cases/control subjects	266/335	404/335	846/334
Crude	1	1.52 (1.22–1.89)	3.19 (2.60–3.92)	<0.001	1.72 (1.58–1.86)	<0.001
Model 1b	1	1.55 (1.24–1.95)	3.25 (2.61–4.04)	<0.001	1.75 (1.60–1.91)	<0.001
Model 2c	1	1.53 (1.22–1.93)	3.00 (2.40–3.75)	<0.001	1.69 (1.54–1.85)	<0.001
Model 3d	1	1.48 (1.17–1.87)	2.92 (2.30–3.69)	<0.001	1.71 (1.55–1.88)	<0.001

^aRange (median).

^bModel 1 adjusted for sex, age (≤40, 40–49, 50–59, ≥60) and body mass index (≤18.5, 18.5–23.9, 24–27.9, ≥28).

^cModel 2 further adjusted for smoking (current, former, and never), drinking (current, former, and never), physical activity (yes or no), hypertension (yes or no), and family history of diabetes (any or none).

^dModel 3 further adjusted for plasma manganese, plasma magnesium, plasma iron, plasma chromium and plasma selenium.