Low serum vitamin K2 and high Gas6 levels correlate with increased aortic arch calcification in hemodialysis patients.
Background
Cardiovascular disease remains the primary cause of mortality in maintenance hemodialysis (MHD) patients, with aortic arch calcification (AACS) and left ventricular hypertrophy (LVH) being prevalent and severe complications. Current standard-of-care often fails to adequately address the progression of these structural changes. The precise role of vitamin K-dependent protein Gas6 and vitamin K2 (MK-7) in the pathophysiology of these calcific and hypertrophic processes in this vulnerable population has remained largely undefined, presenting a critical knowledge gap.
Study Design
This cross-sectional study investigated 189 patients undergoing MHD. Serum levels of vitamin K2 (MK-7) and Gas6 were precisely quantified using enzyme-linked immunosorbent assay (ELISA). Patients were stratified into groups based on LVMI for LVH (n=110) and non-LVH (n=79), and by AACS severity into four distinct groups (n=46, n=54, n=53, n=36). Statistical analyses, including Spearman correlation and multivariate logistic regression, were employed to assess the relationships between these biomarkers and cardiovascular structural changes.
Results
Patients with LVH were significantly older and exhibited higher levels of BNP, creatinine, and Gas6, alongside notably lower vitamin K2 levels (P<0.05). Across the four AACS severity groups, significant differences were observed in age, glucose, phosphorus, calcium-phosphorus product, vitamin K2, and Gas6 levels. A strong positive correlation was identified between vitamin K2 and calcium (r=0.822), while a negative correlation was found between vitamin K2 and Gas6 (r=-0.339). Multivariate analysis revealed that age >65 years and vitamin K2 levels <2.39 nmol/L were independent risk factors for increased AACS severity. Importantly, the study found:
No significant correlation between serum vitamin K or Gas6 levels and LVH in MHD patients. However,
AACSdemonstrated a clear negative correlation with vitamin K and a positive correlation with Gas6.
Key Findings
- LVH patients had lower serum vitamin K2 and higher Gas6 levels (P<0.05).
- Serum vitamin K2 correlated positively with calcium (r=0.822) and negatively with Gas6 (r=-0.339).
- Age >65 years and vitamin K2 <2.39 nmol/L were independent risk factors for
AACS. - No correlation was found between serum vitamin K or Gas6 and LVH.
- Aortic arch calcification (AACS) negatively correlated with vitamin K and positively with Gas6.
Why It Matters
This study highlights a potential role for vitamin K2 and Gas6 in the progression of aortic arch calcification (AACS) in MHD patients, suggesting that maintaining adequate vitamin K2 levels might be a modifiable factor. For clinicians and biohackers, this implies that vitamin K2 supplementation could be a relevant consideration for MHD patients at risk of or with existing AACS, although further interventional studies are needed to confirm causality and establish optimal dosing protocols. The finding that vitamin K2 levels below 2.39 nmol/L are an independent risk factor for AACS provides a specific threshold that could guide future diagnostic and therapeutic strategies. This research suggests that targeting vitamin K2 status could offer a novel approach to mitigate vascular calcification in MHD, but not necessarily left ventricular hypertrophy.
vitamin-k2
gas6
aortic-arch-calcification
left-ventricular-hypertrophy
hemodialysis
cardiovascular-disease