Table 1 Baseline participant characteristics according to protein intake categories

N

196

92

73

31

Age, y

72.65 (5.95)

73.65 (5.88)

71.80 (5.91)

71.68 (6.00)

0.086^a

Female, No. (%)

138 (70.41)

64 (69.57)

51 (69.86)

23 (74.19)

0.880^b

Education, No. (%)

9.62 (4.51)

9.30 (4.67)

9.49 (4.02)

10.87 (5.01)

0.236^a

MMSE

25.58 (3.45)

24.93 (3.97)

25.62 (2.98)

27.42 (1.88)

0.002^a

APOE4 positivity, No. (%)

40 (20.41)

16 (17.39)

14 (19.18)

10 (32.26)

0.196^b

Clinical diagnosis, CN, No. (%)

113 (57.65)

52 (56.52)

40 (54.79)

21 (67.74)

0.453^b

VRS, %

23.98 (18.58)

26.99 (19.27)

22.15 (18.44)

19.35 (15.57)

0.079^a

GDS score

10.92 (7.24)

11.47 (7.15)

10.92 (7.50)

9.29 (6.88)

0.353^a

PASE total score

64.77 (46.21)

68.75 (49.22)

63.84 (45.07)

55.16 (38.80)

0.360^a

Annual income, No. (%)

0.004^b

 < MCL

25 (12.75)

17 (18.48)

7 (9.59)

1 (3.23)

 ≥ MCL, < 2 × MCL

62 (31.63)

29 (31.52)

29 (39.73)

4 (12.90)

 ≥2\(\:\times\:\)MCL

109 (55.61)

46 (0.50)

37 (50.68)

26 (83.87)

Decrease in food intake over the past three months

0.368^b

 no, n (%)

182 (92.86)

83 (90.22)

70 (95.89)

29 (93.55)

 yes, n (%)

14 (7.14)

9 (9.78)

3 (4.11)

2 (6.45)

Fruit or vegetables, n (%)

0.679^b

 high

119 (60.71)

55 (59.78)

43 (58.90)

21 (67.74)

 low

77 (39.29)

37 (40.22)

30 (41.10)

10 (32.26)

Serum nutritional markers

 Glucose, fasting, mg/dL

108.15 (19.94)

110.53 (20.88)

104.74 (14.41)

109.23 (27.01)

0.173^a

 HDL-Cholesterol, mg/dL

54.64 (12.96)

51.91 (12.75)

56.38 (13.09)

58.70 (11.80)

0.015^a

 LDL-Cholesterol, mg/dL

96.40 (33.82)

95.31 (35.07)

97.85 (31.52)

96.23 (36.34)

0.893^a

Malnutrition, No. (%)

0 (0.00)

0 (0.00)

0 (0.00)

0 (0.00)

CERAD-NP

Total score

69.98 (15.61)

66.66 (14.38)

68.45 (14.46)

83.42 (15.13)

< 0.001^a

Episodic memory score

35.10 (9.48)

33.66 (9.27)

33.67 (8.91)

42.71 (7.90)

< 0.001^a

Non-memory score

34.25 (6.62)

33.22 (6.86)

33.96 (6.10)

38.00 (6.62)

0.002^a