Table 2.

Summary of observational studies of circulating vitamin K status and cardiovascular-related outcomes in chronic kidney disease populations

Author, year	Country	Study design	Participants	Vitamin K status exposure	Outcome	Results for highest vs. lowest quantile
Cross-sectional CKD studies
Cranenburg, 2009 [44]	Netherlands	Cross-sectional	N = 40 hemodialysis patients	Plasma ucMGP (pmol/L)	CAC scores	β = 0.004, P = 0.02
Delanaye, 2014 [45]	Belgium	Cross-sectional	N = 160 hemodialysis patients, age 74 years, 56% female	Plasma dp-ucMGP (pmol/L)	Calcification score	β = 0.19 P = 0.021
Meuwese, 2015 [46]	Sweden	Cross-sectional	N = 97 end-stage renal disease patients, 65% dialysis, age 45.1 years, 63% female	Dp-ucMGP (pmol/L), PIVKA-II (mAU/ml)	Coronary calcification score, arterial stiffness	Not associated with calcification, aortic augmentation pressure β 2.2 (−1, 5.4) NS
Thamratnopkoon, 2016 [47]	Thailand	Cross-sectional	N = 83 CKD 3–5 patients, age 64.8 years, 44% female	Plasma dp-ucMGP (pmol/L)	Abdominal aorta calcification	OR 1.002 (1.001, 1.004)
Longitudinal CKD studies
Schurgers, 2010 [48]	France	Longitudinal 2.2 years follow-up	N = 107 CKD patients stage 2–5, age 67 years, 40% female	Plasma dp-ucMGP (pmol/L)	All-cause mortality	HR 1.57 (0.67, 3.67)
Schlieper, 2011 [49]	Serbia	Longitudinal 3 years follow-up	N = 188 hemodialysis patients	Plasma dp-ucMGP (pmol/L)	All-cause mortality and CVD mortality	HR 2.16 (1.1, 4.3) all-cause mortality, 2.74 (1.2, 6.2) CVD mortality
Keyzer, 2015 [50••]	Netherlands	Longitudinal, 9.8 years follow-up	N = 518 kidney transplant recipients	Plasma dp-ucMGP (pmol/L)	All-cause mortality	HR 2.00 (1.20, 3.35), Q4 vs. Q1

Dp-ucMGP dephosphorylated uncarboxylated matrix gla protein, CKD chronic kidney disease, NS non-significant, OR odds ratio, HR hazard ratio