Table 1 Characteristics of the participants at baseline and after 2 years of intervention with either folic acid and vitamin B₁₂ or placebo

Baseline characteristics

 Age at baseline (years)

70.8 ± 2.9

71.1 ± 3.0

 Women (%)

25 (57 %)

22 (51 %)

 Body mass index (kg/m²)

27.2 (24.4–29.7)

28.7 (25.7–31.2)

 Smoking (%)^a

 Former

25 (57 %)

31 (72 %)

 Never

19 (43 %)

12 (28 %)

MTHFR C677T genotype (%)^b

 CC

22 (50 %)

20 (47 %)

 TT

22 (50 %)

23 (54 %)

Biochemical analyses

Serum folate levels (nmol/L)

 Baseline

16.2 (13.1–24.4)

17.3 (14.1–21.5)

 After intervention

52.3 (45.1–67.6)

23.1 (18.3–26.9)

 Change

34.0 (26.5–47.6)

5.4 (2.0–9.6)

Serum vitamin B₁₂ levels (pmol/L)

 Baseline

279 (232–358)

300 (204–365)

 After intervention

595 (467–814)

325 (230–449)

 Change

319 (197–462)

30.4 (−12.6–89.5)

Plasma homocysteine levels (μmol/L)

 Baseline

14.7 (13.1–16.3)

14.9 (13.1–16.3)

 After intervention

9.6 (8.5–11.1)

13.7 (11.8–16.6)

 Change

−5.3 (−6.7 to −3.4)

−1.5 (−2.4–0.6)