Table 1. Demographics and clinical measures of aMCI patients and healthy control subjects.
| Items | HC | aMCI | t values(χ2) | pvalues |
|---|---|---|---|---|
| n = 129 | n = 85 | |||
| Age (years) | 68.43(6.59) | 69.48(7.52) | −1.085 | 0.279 |
| Gender (male/female) | 64/65 | 46/39 | 0.416 | 0.519 |
| Education level (years) | 12.39(3.04) | 11.84(3.22) | 1.271 | 0.205 |
| MMSE scores | 28.22(1.43) | 26.25(2.65) | 7.035 | 0.000* |
| MDRS_2 | 137.92(3.57) | 131.29(6.85) | 9.252 | 0.000* |
| HAMD scores | 1.63(2.39) | 1.81(3.11) | −0.481 | 0.631 |
| Composite Z scores of each cognitive domain | ||||
| Episodic memory | 0.50(0.50) | −0.75(0.71) | 15.266 | 0.000* |
| information processing speed | −0.12(0.35) | 0.19(0.59) | −4.78 | 0.000* |
| Executive function | 0.04(0.35) | −0.07(0.36) | 2.292 | 0.000* |
| Visuospatial function | 0.32(0.66) | −0.04(0.35) | 7.768 | 0.000* |
Notes: Values are expressed as the mean (standard deviation, SD). Abbreviations: HC, healthy controls; aMCI, amnestic mild cognitive impairment; MMSE, Mini mental state exam; MDRS-2, Mattis Dementia Rating Scale-2; HAMD, Hamilton Depression Scale. *Significant differences are found between aMCI and HC subjects. P values are obtained by t test except for gender (chi square test). The performances of MMSE and MDRS-2 are presented as raw scores. The level of each cognitive domain is denoted by the composite Z scores. Raw scores and corresponding Z scores of individual neuropsychological tests are shown in Supplementary Table1.