Table 1 Differences in baseline demographic characteristics (mean ± SD)

Age (years)^a

67.68 ± 5.83

65.52 ± 5.55

1.341

0.186

Gender (female/male)^c

18/7

20/5

0.439

0.508

Education (years)^a

8.76 ± 2.95

9.84 ± 3.35

 − 1.210

0.232

Body mass index (kg/m²)^a

23.51 ± 3.59

22.74 ± 2.69

0.864

0.392

Diabetes (yes/no)^c

4/21

7/18

1.049

0.306

Hypertension (yes/no)^c

11/14

5/20

3.309

0.069

HAMD^b

2.16 ± 2.25

1.44 ± 1.76

 − 1.066

0.286

IADLs^b

22.52 ± 0.92

22.52 ± 0.77

 − 0.425

0.671