Table I.
Characteristics of 17 randomized controlled trials included in the meta-analysis.
| Studies | Country | Health status | Sex | Mean age, yrs (SD) |
Mean BMI, kg/m2 (SD) |
Duration | Intervention type (no. patients) |
Control type (no. patients) |
Dose of Vit K |
|---|---|---|---|---|---|---|---|---|---|
| Booth et al32 (2008)* |
USA | Healthy | F/M | 68.41 (5.56) | N/A | 3 yrs | Vit K1+ Ca + Vit D (229) | Ca + Vit D (223) |
500 μg/day |
| Zhang et al31 (2020) |
China | Healthy | F/M | 59.78 (6.60) | 24.1 (3.3) | 1 yr | Vit K2-1 (MK-7) (79), Vit K2-2 (MK-7) (74) |
Placebo (61) |
50 μg/day, 90 μg/day |
| Sim et al36 (2020)† |
Australia | Healthy | F/M | 61.80 (9.90) | 27.0 (3.9) | 4 wks | Vit K1 (30), Vit K1 (30) |
Blank control (30) |
164.3 μg/day, 9.4 μg/day (low) |
| Shea et al41 (2008)* |
USA | Healthy | F/M | 69.00 (6.00) | N/A | 3 yrs | Vit K1+ Ca + Vit D (189) |
Ca + Vit D (190) |
500 μg/day |
| Inaba et al33 (2015)‡ |
Japan | Healthy | F/M | 47.00 (14.00) | 21.8 (2.2) | 3 mths | Vit K2 (MK-7) (58) |
Placebo (57) |
100 mg/day |
| Bolton-Smith et al37 (2007)§ | UK | Healthy | F | 67.75 (5.46), 68.61 (5.96) |
26.3 (3.5), 25.9 (3.5) |
2 yrs | Vit K1 (54), Vit K1 + Ca + Vit D (49) |
Placebo (56), Ca + Vit D (50) | 200 μg/day, 200 μg/day |
| Tanaka et al30 (2017) |
Japan | Osteoporosis | F | 75.30 (5.85) | 23.3 (3.8) | 2 yrs | Vit K2 + Risedronate (931) | Risedronate (n = 943) |
45 mg/day |
| Je et al38 (2011) | South Korea | N/A | F | 67.60 (6.29) | N/A | 6 mths | Vit K2 + Ca + Vit D (18) | Ca + Vit D (27) | 45 mg/day |
| Yuanyang et al24 (2019) |
China | Osteoporosis | F | 64.07 (9.63) | N/A | 1 yr | Vit K2 (n = 70) | Blank control (n = 70) | 45 mg/day |
| Shiraki et al25 (2000) |
Japan | Osteoporosis | F | 67.20 (1.13) | N/A | 2 yrs | Vit K2 + Ca (120) | Placebo + Ca (121) |
100 mg/day |
| Binkley et al40 (2009) |
USA | Healthy | F | 62.50 (0.68) | N/A | 1 yr | Vit K1 + Ca + Vit D (126), Vit K2 (MK-4) + Ca + Vit D (126) | Placebo + Ca + Vit D (129) | 1 mg/day, 45 mg/day |
| Cheung et al39 (2008) | Canada | Osteopenia | F | 59.05 (9.57) | 26.2 (4.5) | 4 yrs | Vit K1 + Ca + Vit D (n = 33) | Placebo + Ca + Vit D (40) | 5 mg/day |
| Knapen et al43 (2007) |
Netherlands | Healthy | F | 65.95 (0.46) | 27.2 (0.4) | 3 yrs/1 yr | Vit K2 (MK-4) (161) | Placebo (164) | 45 mg/day |
| Purwosunu et al44 (2006) | Indonesia | Osteoporosis | F | 60.76 (5.25) | 23.2 (3.9) | 1 yr | Vit K2 + Ca (33) | Placebo + Ca (30) |
45 mg/day |
| Miki et al42 (2003) | Japan | Osteoporosis | F | 75.80 (6.26) | N/A | 2 wks | Vit K2 (MK-4) + Ca (10) | Ca (10) | 45 mg/day |
| Dalmeijer et al34 (2012) | Netherlands | Healthy | F/M | 54.49 (2.96) | N/A | 3 mths | Vit K2 (MK-7)(22), Vit K2 (MK-7) (18) | Placebo (20) | 180 μg/day (low), 360 μg/day |
| Roenn et al35 (2021) |
Denmark | Osteopenia | F | 67.26 (4.38) | N/A | 3 yrs | Vit K2 (MK-7) + Ca + Vit D (62) | Placebo + Ca + Vit D (57) | 375 μg/day |
*
The same study subjects were used in both studies, but they showed different indicators.
†
The included participants did not mention bone-related diseases and were considered healthy by default.
‡
There were two studies by this author, and only study 2 was listed here.
§
There were four groups in this study, which have been divided into two studies.
N/A, not available (unable to consolidate or not provided).