Vitamin K1 and K2 in the Diet of Patients in the Long Term after Kidney Transplantation

Vitamin K, especially its K2 form, is considered to be a protective factor against developing vascular changes and bone lesions that are common complications in kidney transplant (KTx) recipients. There is a growing number of studies showing that KTx patients are at risk of vitamin K deficiency. The aim of this study was to evaluate the intake of vitamin K1 and K2 in the diet of patients in the late period after KTx. During a routine visit at one outpatient transplantation clinic in Central Europe, a diet survey questionnaire was filled in by 151 clinically stable KTx recipients and compared with medical history, anthropometric measurements and laboratory tests. Mean vitamin K1 intake was 120.9 +/- 49 mu g/day and vitamin K2 (MK, menaquinone) intake 28.69 +/- 11.36 mu g/day, including: MK-4: 25.9 +/- 9.9 mu g/day; MK-5: 0.1 +/- 0.2 mu g/day; MK-6: 0.2 +/- 0.4 mu g/day; MK-7: 0.2 +/- 0.23 mu g/day; MK-8: 1 +/- 1.9 mu g/day; MK-9: 0.9 +/- 2.3 mu g/day; and MK-10: 0.2 +/- 0.5 mu g/day. Our study showed that KTx recipients' diets contained adequate amounts of vitamin K1, whereas the intake of vitamin K2 seemed insufficient.