Vitamin K1 Tied to Lower Atherosclerosis in Older Women

Higher vitamin K1 intakes are associated with lower subclinical atherosclerosis and lower risk for atherosclerotic vascular disease (ASVD)-related outcomes, including ischemic heart disease and ischemic cerebrovascular disease subtypes, in older women, according to research published in the European Journal of Nutrition

“Although older women present with a unique risk profile for ASVDs, they are often underrepresented in research,” explained the study authors. “Lifestyle factors, such as healthy dietary patterns rich in vegetables, are known to reduce ASVD risk… This association may be attributed to common nutrients found within [higher cruciferous and leafy green] vegetables, such as vitamin K1.”

The researchers evaluated the association between dietary vitamin K1 intake, estimated using a region-specific food database, and subclinical atherosclerosis (common carotid artery intima–media thickness [CCA-IMT]) and long-term ASVD events (hospitalizations and/or mortality) in a cohort of older Australian women.

The study included 1,436 women (mean age, 75.1 years) from the Perth Longitudinal Study of Ageing Women (PLSAW), which began in 1998 (baseline). At baseline, participants completed a validated food frequency questionnaire to estimate their vitamin K1 intake, and in 2001, they underwent CCA-IMT measurement (n=1,090).

The median baseline vitamin K1 intake was 78.7 μg/day. The investigators found that women with higher vitamin K1 intakes had a 5.6% lower mean CCA-IMT (Quartile [Q] 4 median, 119 µg/day) compared with those with lower intakes (Q1 median, 49 µg/day; P<0.001).

Based on data from linked health records from over 14.5 years of follow-up, 43.1% of the women experienced an ASVD event, 34.6% of the women experienced an ASVD hospitalization, and 20.9% of the women died from ASVD-related causes.

In multivariable-adjusted models using a follow-up period of 14 years, women with the highest vitamin K1 intakes, compared with those with the lowest intakes (Q4 vs Q1), had significantly lower relative hazards for ASVD events (hazard ratio [HR], 0.74; 95% CI, 0.57-0.96) and ASVD mortality (HR, 0.57; 95% CI, 0.40-0.83), but not for ASVD hospitalizations.

“In the context of global dietary vitamin K1 intake recommendations (1 μg/kg/day or ~70 μg/day for a reference adult), we report that vitamin K1 intakes that met (Q2) and exceeded these recommendations (Q3 and Q4) appear to be beneficial for cardiovascular health,” wrote the authors. “From a public health perspective, increasing leafy green or cruciferous vegetable intake by one serving (~0.5-1 cup) a day, to achieve adequate vitamin K1 intakes, may be a low-risk and effective strategy to improve cardiovascular health.”

Disclosure(s):

All authors declare no conflicts of interest.