Table 1 Demographics and ocular characteristics of mild cognitive impairment (MCI) cases, Alzheimer’s disease (AD) cases, and cognitively normal controls

Age

71.0 ± 4.7

73.4 ± 6.3

73.3 ± 8.7

0.078

Gender, female

31 (56)

58 (54)

39 (63)

0.505

Diabetes, yes

8 (15)

35 (32)

21 (34)

0.031

Hypertension, yes

31 (56)

61 (57)

44 (72)

0.111

Systolic blood pressure, mmHg

137 ± 16

142 ± 16

142 ± 19

0.113

Diastolic blood pressure, mmHg

73 ± 9

74 ± 10

71 ± 11

0.304

Global CDR Score

0.11 ± 0.21

0.32 ± 0.24

1.17 ± 0.41

< 0.001

Signal strength, optic disc

7.56 ± 1.05

7.64 ± 1.13

7.92 ± 1.02

0.053

Signal strength, macular

7.81 ± 1.00

7.89 ± 1.15

7.97 ± 1.05

0.644

Optic disc area, mm²

1.86 ± 0.39

1.97 ± 0.39

1.98 ± 0.35

0.083

Optic disc ratio

1.13 ± 0.09

1.14 ± 0.08

1.13 ± 0.07

0.661

Optic disc orientation, degrees

95.85 ± 33.15

97.23 ± 31.15

99.51 ± 32.77

0.741

Fovea distance, μm

4.52 ± 0.29

4.53 ± 0.29

4.53 ± 0.28

0.935

Fovea angle, degrees

− 8.06 ± 3.95

− 7.74 ± 4.20

− 7.83 ± 4.34

0.846

Spherical equivalent refractive error, dioptres

− 1.11 ± 2.76

0.03 ± 1.88

− 0.06 ± 1.67

< 0.001