Table 3. Element levels (μg/L) in serum of patients and healthy subjects.

Element	HS	SMC	MCI	AD	Kruskal-Wallis		Pairwise comparisonsa(p value)
	(n = 40)	(n = 24)	(n = 20)	(n = 34)	H (3)	p value	ADvsHS	ADvsSMC	ADvsMCI	HSvsSMC	HSvsMCI	MCIvsSMC
Al	2.96 ± 0.76(2.71 to 5.70)	3.06 ± 0.84(2.71 to 5.60)	3.46 ± 2.04(2.71 to 10.86)	3.25 ± 1.58(2.71 to 10.94)	1.369	0.714	N/A	N/A	N/A	N/A	N/A	N/A
Be	0.02 ± 0.02(0.02 to 0.12)	0.03 ± 0.04(0.02 to 0.19)	0.02 ± 0.02(0.02 to 0.11)	0.03 ± 0.07(0.02 to 0.39)	0.180	0.981	N/A	N/A	N/A	N/A	N/A	N/A
Ca	7.2 ± 2.6*(2.67 to 10.9)*	7.9 ± 1.4*(5.16 to 9.91)*	7.7 ± 2.2*(4.12 to 10.5)*	8.1 ± 2.1*(3.99 to 10.8)*	1.163	0.762	N/A	N/A	N/A	N/A	N/A	N/A
Cd	0.02 ± 0.01(0.02 to 0.07)	0.02 ± 0.01(0.02 to 0.06)	0.03 ± 0.02(0.02 to 0.09)	0.03 ± 0.02(0.02 to0.08)	2.703	0.069	N/A	N/A	N/A	N/A	N/A	N/A
Cr	0.21 ± 0.25(0.06 to 1.19)	0.17 ± 0.13(0.06 to 0.60)	0.18 ± 0.24(0.06 to 1.14)	0.10 ± 0.06(0.06 to 0.34)	7.093	0.297	N/A	N/A	N/A	N/A	N/A	N/A
Sb	3.23 ± 0.51(2.46 to 4.77)	2.78 ± 0.48(1.55 to 3.97)	3.18 ± 1.23(1.58 to 6.34)	2.67 ± 1.29(0.04 to 5.76)	15.532	0.001	0.002	n.s.	n.s.	0.047	n.s.	n.s.
Sn	0.14 ± 0.10(0.05 to 0.39)	0.11 ± 0.09(0.05 to 0.47)	0.16 ± 0.14(0.05 to 0.49)	0.22 ± 0.21(0.05 to 0.90)	3.687	0.297	N/A	N/A	N/A	N/A	N/A	N/A
U	0.02 ± 0.01(0.01 to 0.04)	0.02 ± 0.01(0.01 to 0.08)	0.03 ± 0.02(0.01 to 0.12)	0.03 ± 0.02(0.01 to 0.09)	3.829	0.281	N/A	N/A	N/A	N/A	N/A	N/A
V	0.04 ± 0.01(0.03 to 0.09)	0.04 ± 0.02(0.03 to 0.11)	0.08 ± 0.04(0.03 to 0.20)	0.08 ± 0.04(0.03 to 0.53)	34.116	<0.001	<0,001	0.009	n.s.	n.s.	<0.001	0.016

Results are reported as mean ± standard deviation and (range). Statistical analysis has been performed by Kruskal-Wallis H test.

^aDunn’s post hoc analysis; N/A, not applicable;*, value are 1*10⁴; n.s., not significant; HS, healthy subjects; SMC, subjective memory complaint; MCI, mild cognitive impairment; AD, Alzheimer’s disease.