Dietary vitamin K intakes and atherosclerotic cardiovascular disease incidence: Findings from the UK biobank

Background and Aims Vitamin K is essential for processes that inhibit vascular and valvular calcification, attributes of atherosclerotic cardiovascular diseases (ASCVDs) and aortic stenosis (AS). Relationships between dietary vitamin K1 and K2 intakes, ASCVD and AS were explored. Methods In 112,111 participants from the UK Biobank without ASCVD or AS (median age 59.7 years, 57.3% female), dietary vitamin K1 (μg/day) and K2 (μgPKeq/day) intakes were calculated from Oxford WebQ 24-hour dietary questionnaires, using vitamin K food composition databases. Associations with incident ASCVD, ASCVD subtypes and AS, obtained from self-reports, primary care data, hospital records and death registries, were examined using restricted cubic splines within multivariable-adjusted Cox proportional hazards models. Results Over a median follow-up of 10.5 years, 8,696 ASCVD cases were recorded. Non-linear associations between vitamin K1 intakes and ASCVD were observed within multivariable-adjusted models (p non-linearity ≤0.01). Higher vitamin K1 intakes were associated with a 7-10% lower risk of ASCVD, with no advantage observed beyond moderate intakes (HR Q3vsQ1 0.90 [0.85-0.95]). Lower risk relationships were also found for ischemic heart disease (IHD), ischemic stroke and peripheral arterial disease but not AS. The highest vitamin K2 intakes were associated with a greater risk of incident ASCVD (HR Q5vsQ1 1.07 [1.01-1.14]), IHD and AS. Conclusions Among adults without prevalent ASCVD, those with higher dietary vitamin K1, but not K2, intakes had lower ASCVD risk. Positive associations with vitamin K2 may reflect food source confounding warranting further investigation. These findings reinforce the promotion of vitamin K1-rich vegetable consumption (e.g. spinach and broccoli) to support cardiovascular health.