Table 1 Baseline characteristics of the participants by the quartile of MMA levels

Age (year)

71 (65–80)

67 (63–72)

72 (64.75-80)

73 (66–80)

74 (67.75-80)

< 0.001

Male (%)

52.4

53.8

54.1

52.1

49.3

0.259

Education

Less than 9th grade (%)

16.4

16.8

16.4

14.8

17.6

9 − 11th grade (%)

17.1

14

17.1

19

18.3

High school graduate (%)

24.6

26.6

23.3

22.5

26.1

College or AA degree (%)

25

25.9

24

25.4

24.6

College graduate or above (%)

16.9

16.8

19.2

18.3

13.4

Smoke (%)

37

40.7

34.5

36

36.6

< 0.001

Drink (%)

64.2

69.6

60.6

62.5

64.2

< 0.001

Hypertension (%)

75.3

74.8

78.1

70.4

77.5

< 0.001

Diabetes (%)

41.2

44.1

39

40.1

40.8

< 0.001

BMI (kg/m2)

28.12 (24.25–32.65)

28.05 (24.75–32.3)

28.66 (25.41–33.29)

27.59 (23.6-32.47)

28.17 (24.38–32.5)

0.295

GNRI

104.18 (100.1-107.29)

105.53 (101.87-108.54)

105.4 (102.66-107.43)

104.32 (100.87-107.31)

103.34 (99.72-106.98)

0.006

< 82 (%)

10.5

2.1

3.4

4.2

4.9

82–92 (%)

1.1

0.7

2.8

1.4

92–98 (%)

5.8

6.3

2.7

4.2

12

> 98 (%)

82.5

91.6

93.2

88.7

81.7

Hemoglobin (g/dl)

13.5 (12.5–14.5)

13.7 (13-14.7)

13.61 ± 1.42

13.45 ± 1.54

13.09 ± 1.82

0.001

Anemia (%)

10.5

4.2

7.5

12

17.6

0.001

RDW (%)

13.7 (13-14.6)

13.5 (12.8–14.3)

13.6 (13-14.4)

13.6 (13-14.53)

14.05 (13.3–14.9)

0.002

Albumin (g/l)

42 (39–43)

42 (40–44)

42 (40–43)

41 (39–43)

41 (38–43)

0.013

Cholesterol (mmol/l)

4.66 (3.91–5.61)

4.68 (3.83–5.82)

4.62 (3.85–5.72)

4.66 (4.01–5.33)

4.79 ± 1.19

0.945

Triglyceride (mmol/l)

1.55 (1.04–2.43)

1.49 (0.85–2.41)

1.59 (1-2.39)

1.52 (1.11–2.44)

1.62 (1.12–2.44)

0.378

BUN (mmol/l)

11 (6.07-17)

8.57 (4.64-13)

9 (5.71-16)

12 (7.5–19.5)

15 (8.48-25)

< 0.001

Creatinine (mmol/l)

90.17 (71.6-117.57)

74.26 (63.65–87.52)

89.73 (72.49-108.95)

99.89 (79.12-123.76)

110.06 (81.11-179.23)

< 0.001

Uric acid (mg/dl)

5.9 (4.9–7.2)

5.4 (4.6–6.6)

5.8 (5–7)

5.9 (5.1–7.2)

6.45 (4.9–7.8)

< 0.001

Vitamin D3 (nmol/l)

61.3 (41.64–85.05)

58.93 (39.7-77.94)

65.27 (41.72–85.45)

64.75 (46.15–88.78)

58.45 (38.9–89.9)

0.178

Vitamin B12 (pg/ml)

556 (386–775)

638 (403.5–850)

617 (462–812)

552.5 (384-780.25)

462 (318.5–643)

< 0.001

Folate (ng/ml)

549.5 (404–787)

498.5 (369.75-671.25)

596 (415–848)

589.5 (415.5–799)

556 (422.5–830)

0.021

CERAD-WL

18 (14–21)

19 (14–22)

18 (14.75-21)

17 (14–21)

16.5 (13–20)

0.022

CERAD-DR

6 (4–7)

6 (4–7)

6 (4–7)

5 (3–7)

5 (3–7)

0.181

Animal frequency test

15 (11–18)

15.31 ± 5.35

15 (11.75-18)

15 (11–19)

14 (10–18)

0.047

DSST

38 (24–49)

38.97 ± 18.12

39.36 ± 18.18

35.73 ± 19.41

32 (19.75-44)

0.001

Methylmalonic acid

194 (141.5–283)

115 (100–129)

168 (153–183)

221.5 (204-244.25)

397.5 (329.5-536.5)

< 0.001