Investigating the associations between uncarboxylated matrix gla protein as a proxy for vitamin K status and cardiovascular disease risk factors in a general adult population

PURPOSE: Vitamin K is an activator of vitamin K dependent proteins, one of which is the potent inhibitor of vascular calcification, matrix Gla protein (MGP). The purpose of this study is to investigate the association between an inverse proxy of functional vitamin K status, plasma dephospho-uncarboxylated MGP (dp-ucMGP), and cardiovascular disease risk factors (CVDRFs).

METHODS: In a cross-sectional population-based health examination study of 4,092 individuals aged 24-77 years, the vitamin K status was assessed using plasma dp-ucMGP. All participants were linked to Danish National Prescription Register to obtain information on the use of vitamin K antagonists. The associations between log2 transformed dp-ucMGP values and CVDRFs were determined using regression models adjusted for sex, age, lifestyle factors, kidney function and waist circumference.

RESULTS: Higher dp-ucMGP levels were associated with increased risk of central obesity (Odds Ratio (OR) 4.76, 95% Confidence Intervals (CI) 3.57-6.34), diabetes (OR 1.96, 95% CI 1.11-3.45), hyperlipidaemia (OR 1.43, 95% CI 1.01-2.03), and impaired kidney function (OR 9.83, 95% CI 5.49-17.59) per doubling in dp-ucMGP. Dp-ucMGP was not independently associated with hypertension or arterial stiffness.

CONCLUSION: Higher dp-ucMGP levels were associated with central obesity, diabetes, hyperlipidaemia, and impaired kidney function. Prospective studies and intervention studies examining the effects of improving vitamin K status are needed to clarify the potential role of vitamin K in relation to these CVDRFs.