Table 1. Demographics of the four groups.

	Severe AD (N = 9)	Mild to moderate AD (N = 7)	aMCI (N = 14)	Control (N = 17)	P-value
Age (years)	74.2 ± 5.9	76.0 ± 11.1	68.6± 7.9	73.6± 7.5	0.107*
Female: Male	5:4	2 : 5	8 : 6	8 : 9	0.75**
MMSE	12.1 ± 5.1	18.4± 4.9	24.2± 2.0		<0.001¶
CDR	1.4 ± 0.7	0.9±0.2	0.5± 0.0		<0.001¶
GDS	5.3 ± 0.5	3.9± 0.4	3.0± 0.0		<0.001¶

N: number of subjects, MMSE: mini-mental status examination, CDR: clinical dementia rating, GDS: global deterioration scale,

* Kruskal-Wallis test,

** Chi-square test,

¶ ANCOVA (covariate: age),

bold type indicates statistical significance.