The ViKTORIES trial: a randomised, double-blind, placebo-controlled trial of vitamin K supplementation to improve vascular health in kidney transplant recipients.
Lees, J. S., et al.American Journal of Transplantation 2021 [record in progress].
Aims
This trial aimed to investigate the effects of vitamin K supplementation on vascular stiffness and calcification in renal transplant recipients.
Interventions
Participants were randomised to either the vitamin K supplementation group or the placebo group.
Participants
90 adult kidney transplant patients (≥18 years).
Outcomes
The primary endpoint was the ascending aortic distensibility. The secondary endpoints included coronary artery calcification score (CACS), carotid-femoral pulse wave velocity and augmentation index, cardiac structure and function, office blood pressure, electrocardiogram (ECG), calcium metabolism and bone turnover markers, transplant function, proteinuria, and quality of life.
Follow-up
12 months
CET Conclusions
This double-blind placebo-controlled phase II study investigated the role of Vitamin K supplementation in kidney transplant recipients (KTR) on surrogate markers of cardiovascular disease. The authors found no difference in vascular stiffness or calcification following 1 year of treatment, leading them to conclude that in an unselected cohort of KTRs, supplementation does not affect markers of cardiovascular risk and is unlikely therefore to have a significant impact on incidence of cardiovascular events. The study is very well designed and reported. Whilst the sample size is small, it does appear adequately powered to detect a clinically significant difference in the primary endpoint selected, and therefore the conclusions are justified. It is likely that supplementation alone in a general transplant population is unlikely to have a significant impact, so further study is required to see if there is benefit in a patient population with a deficiency in vitamin K at baseline.
Data analysis
Modified intention-to-treat analysis
Trial registration
ISRCTN22012044