Table 2.

Associations of blood metal with prevalence of ADL disability in single-metal and multimetal models for participants between 2016 and 2018 in Guangxi, China.

Variables	ORs (95% CIs) for ADL disability per SD higher difference in ${\log }_{10}$-transformed metals for all subjects ($N=\mathrm{4,391}$)		ORs (95% CIs) for ADL disability per SD higher difference in ${\log }_{10}$-transformed metals for subgroup ($n=212$)
	OR (95% CI)	p-Value	OR (95% CI)	p-Value
Single-metal models
Manganese (Mn)	1.14 (1.05, 1.24)	0.002	1.15 (1.01, 1.32)	0.003
Copper (Cu)	1.16 (1.07, 1.26)	$<0.001$	1.16 (1.01, 1.34)	0.001
Zinc (Zn)	1.02 (0.945, 1.11)	0.582	1.00 (0.87, 1.16)	0.964
Arsenic (As)	1.22 (1.13, 1.33)	$<0.001$	1.25 (1.08, 1.45)	$<0.001$
Cadmium (Cd)	1.15 (1.06, 1.26)	0.001	1.16 (1.02, 1.33)	0.002
Lead (Pb)	1.09 (1.00, 1.19)	0.050	1.10 (0.969, 1.26)	0.134
Multimetal model
Manganese (Mn)	1.16 (1.06, 1.26)	0.001	1.15 (1.01, 1.31)	0.003
Copper (Cu)	1.18 (1.08, 1.29)	$<0.001$	1.17 (1.03, 1.35)	0.001
Arsenic (As)	1.17 (1.06, 1.28)	$<0.001$	1.22 (1.11, 1.33)	$<0.001$
Cadmium (Cd)	1.10 (1.00, 1.20)	0.049	1.11 (1.01, 1.21)	0.045

Note: Concentrations of blood manganese, copper, zinc, arsenic, cadmium, and lead were ${\log }_{10}$-transformed due to right-skewed distributions. The OR and 95% CI of ADL disability were estimated by 1-SD higher difference in ${\log }_{10}$-transformed metals as continuous variables. p-Values of single-metal were estimated using multivariate logistic regression models with the inclusion of each metal individually, and p-values of multimetal models derived from including all six metals simultaneously in the multivariate logistic regression model. All models were adjusted for sex (male or female), age (continuous), BMI (continuous), education (less than primary school, primary school, high school and above), annual income ($<\mathrm{10,000}$ RMB, $\ge \mathrm{10,000}$ and $<\mathrm{30,000}$, $\ge \mathrm{30,000}$ RMB), smoking status (current smokers, former smokers, non-smokers), drinking status (current drinkers, former drinkers, non-drinkers), and insomnia (yes or no). ADL, activities of daily living; BMI, body mass index; CI, confidence interval; OR, odds ratio; RMB, renminbi; SD, standard deviation.