Vitamin K supplementation and progression of coronary artery calcium in older men and women.
BACKGROUND
Coronary artery calcification (CAC) is an independent predictor of cardiovascular disease. A preventive role for vitamin K in CAC progression has been proposed on the basis of the properties of matrix Gla protein (MGP) as a vitamin K-dependent calcification inhibitor.


OBJECTIVE
The objective was to determine the effect of phylloquinone (vitamin K1) supplementation on CAC progression in older men and women.


METHODS
CAC was measured at baseline and after 3 y of follow-up in 388 healthy men and postmenopausal women; 200 received a multivitamin with 500 microg phylloquinone/d (treatment), and 188 received a multivitamin alone (control).


RESULTS
In an intention-to-treat analysis, there was no difference in CAC progression between the phylloquinone group and the control group; the mean (+/-SEM) changes in Agatston scores were 27 +/- 6 and 37 +/- 7, respectively. In a subgroup analysis of participants who were > or =85% adherent to supplementation (n = 367), there was less CAC progression in the phylloquinone group than in the control group (P = 0.03). Of those with preexisting CAC (Agatston score > 10), those who received phylloquinone supplements had 6% less progression than did those who received the multivitamin alone (P = 0.04). Phylloquinone-associated decreases in CAC progression were independent of changes in serum MGP. MGP carboxylation status was not determined.


CONCLUSIONS
Phylloquinone supplementation slows the progression of CAC in healthy older adults with preexisting CAC, independent of its effect on total MGP concentrations. Because our data are hypothesis-generating, further studies are warranted to clarify this mechanism. This trial was registered at clinicaltrials.gov as NCT00183001.
Shea
M Kyla
MK
US Department of Agriculture, Human Nutrition Research Center on Aging, Tufts University, Boston, MA 02111, USA.
O'Donnell
Christopher J
CJ
Hoffmann
Udo
U
Dallal
Gerard E
GE
Dawson-Hughes
Bess
B
Ordovas
José M
JM
Price
Paul A
PA
Williamson
Matthew K
MK
Booth
Sarah L
SL
D000368:Aged; D002097:C-Reactive Protein / Q000378:metabolism; D002114:Calcinosis / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000517:prevention & control; D002118:Calcium / Q000032:analysis* / Q000097:blood; D002135:Calcium-Binding Proteins / Q000097:blood*; D017023:Coronary Angiography; D003331:Coronary Vessels / Q000737:chemistry / Q000187:drug effects*; D019587:Dietary Supplements; D004311:Double-Blind Method; D016326:Extracellular Matrix Proteins / Q000097:blood*; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000097:blood; D008297:Male; D008875:Middle Aged; D053244:Osteoprotegerin / Q000097:blood; D017698:Postmenopause; D014812:Vitamin K / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D014815:Vitamins / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D000097568:Matrix Gla Protein
D002097:C-Reactive Protein; D002118:Calcium; D002135:Calcium-Binding Proteins; D016326:Extracellular Matrix Proteins; D015850:Interleukin-6; D053244:Osteoprotegerin; D014812:Vitamin K; D014815:Vitamins; D000097568:Matrix Gla Protein