Vitamin K1 intake and coronary calcification

Objectives The activity of matrix Gla-protein (MGP), a potent inhibitor of vascular calcification, is dependent on carboxylation using vitamin K as a co-factor. In animals, low intake of total vitamin K has been shown to accelerate vascular calcification via the MGP mechanism. This has led to the hypothesis that low levels of dietary vitamin K intake may be a risk factor for accelerated vascular calcification in humans due to decreased MGP activity. Additionally, some authors have suggested that current recommended daily intake values for vitamin K might be insufficient to fully inhibit vascular calcification via the MGP mechanism. The aim of this study was to examine the relationship between dietary vitamin K-1 (the most prevalent dietary form of vitamin K) intake and premature coronary artery calcification (CAC) in an asymptomatic screening population. Methods We conducted a prospective study of 807 consecutive active-duty US Army personnel, 39-45 years of age, without known coronary heart disease. Vitamin K-1 intake was measured with the Block Dietary Questionnaire and CAC was identified using electron-beam computed tomography (EBCT). Results We found no significant correlation between CAC score and vitamin K-1 intake (r = 0.132, P = 0.106). Multivariate analysis with adjustment for cardiac risk factors showed no association between dietary vitamin K, intake and CAC. Conclusions Dietary vitamin K-1 (phylloquinone) intake appears to be unrelated to premature coronary calcification in a screening population. Further investigation into the relationship of vascular calcification and other forms of vitamin K-1 (menaquinones) is indicated. (c) 2005 Lippincott Williams & Wilkins.