Vitamin K intake and all-cause and cause specific mortality (Zwakenberg SR et al.)
Clinical Nutrition has recently published results of a Dutch large-scale cohort study that aimed to investigate the association of Vitamin K1 (phylloquinone) and Vitamin K2 (menaquinone) intake with all-cause and cause-specific mortality. The present study was fifth of the kind trying to detect such as association. It included 33,289 participants from the EPIC-NL (European Prospective Investigation into Cancer and Nutrition) cohort, aged 20-70 years at baseline and recruited between 1993 and 1997.
Dietary intake was assessed at baseline with a validated food frequency questionnaire and intakes of Vitamin K1 (phylloquinone), and total Vitamin K2 (short chain MK-4–MK-6 and long chain MK-7–MK-10 menaquinones) were calculated. Information on vital status and causes of death was obtained through linkage to several registries. The association between the different forms of Vitamin K intake and mortality was assessed with Cox proportional hazards, adjusted for risk factors for chronic diseases and nutrient intake. During a mean follow-up of 16.8 years, 2863 deaths occurred, including 625 from cardiovascular diseases (CVD) (256 from coronary heart disease (CHD)), 1346 from cancer and 892 from other causes.
After applying multivariable adjustment, the researchers found that Vitamin K1 (phylloquinone) and Vitamin K2 (menaquinones) were not associated with all-cause mortality with hazard ratios for the upper vs. the lowest quartile of intake of 1.04 (0.92;1.17) and 0.94 (0.82;1.07) respectively. Neither K1 nor K2 intake was associated with risk of CVD mortality. Higher intake of long chain menaquinones (MK-7–MK-10) was borderline significantly associated (ptrend = 0.06) with lower CHD mortality with a HR10µg of 0.86 (0.74;1.00). None of the forms of Vitamin K intake were associated with cancer mortality or mortality from other causes.
“This study found no significant associations between phylloquinone or menaquinone intake and all-cause or cause specific mortality,” says Dr. Katarzyna Maresz, president of the International Science and Health Foundation. “Published twelve years after the Rotterdam study, it constitutes an important continuation of the previous Dutch cohort research in terms of stating that only the intake of long chain menaquinones may be associated with a reduced risk of CHD,” Dr. Maresz concludes.
Reference:
Zwakenberg SR, et al., Vitamin K intake and all-cause and cause specific mortality, Clinical Nutrition (2016), http://dx.doi.org/10.1016/j.clnu.2016.08.017