Our study has several strengths. The study population is large, multiethnic, nationally-representative, and well-characterized with data on multiple risk factors and confounders. The long follow-up and the large number of events provided ample statistical power. Exclusion of participants on warfarin therapy or with stroke reduced potential bias from dietary changes due to known diseases. Nevertheless, there are limitations. The main limitation of this study was that the estimation of vitamin K intake was based on single self-reported dietary recall information, which can lead to potential misclassification bias. Dietary assessment was available only at one time point. Participants' diets and food composition might have changed during the follow-up period. However, since this study included only CKD patients, they likely follow specific diets, which remain stable during the follow-up. Further, a previous study reported that dietary pattern classification is moderately stable over time.30 There may be residual confounding, for example, confounding factors for all-cause and cardiovascular mortality in CKD, such as bone-specific alkaline phosphatase,19 were not accounted for in the current study. However, we have already included major and well established risk factors in the multivariable model in our effort to control for confounding factors. This study could not differentiate between the effects of dietary vitamin K1 and K2, however the current recommended adequate intake is based on total vitamin K, therefore our study adds to the importance of total vitamin K on clinical outcomes. We did not have measurement of serum vitamin K or biomarkers that could reflect vitamin K status, such as osteocalcin, desphospho-uncarboxylated MGP, and Proteins Induced by Vitamin K Absence (PIVKA-II). In addition, excess intake of vitamin K may influence International Normalized Ratio in hemodialysis patients, creating greater susceptibility to bleeding, therefore a cautious use of vitamin K is required to these patients. Similarly, further research is required to examine whether vitamin K confers differential effect on different stages of CKD.