Table 2.

Adjusted odds ratios (95% CI) for CKD according to quartiles of exposure for plasma elements in the logistic regression models.

Plasma elements	Odds ratio (95% CI)				p-Trend
	Q1	Q2	Q3	Q4
Manganese(μg/L)	<13.63	13.63–28.80	28.80–63.87	>63.87
Model1	1	0.52 (0.30–0.91)	0.61 (0.35–1.03)	0.68 (0.40–1.16)	0.22
Model2	1	0.48 (0.27–0.85)	0.68 (0.39–1.20)	0.95 (0.54–1.67)	0.89
Iron(μg/L)	<1964.42	1964.42–3818.90	3818.90–7608.24	>7608.24
Model1	1	0.68 (0.40–1.16)	0.34 (0.19–0.58)	0.37 (0.21–0.65)	<0.001
Model2	1	0.75 (0.44–1.31)	0.34 (0.19–0.61)	0.34 (0.19–0.62)	<0.001
Zinc(μg/L)	<1078.14	1078.14–2071.06	2071.06–3201.89	>3201.89
Model1	1	0.97 (0.57–1.65)	0.64 (0.38–1.10)	0.48 (0.28–0.83)	0.003
Model2	1	1.01 (0.58–1.75)	0.73 (0.41–1.28)	0.50 (0.28–0.89)	0.009

Model1: plasma elements were included in the unconditional logistic regression models separately (single-element model) and adjusted for age, sex, BMI, education and county/city.

Model2: plasma elements were included in the logistic regression models simultaneously (multiple-elements model) and adjusted for the same variables as Model1.