#5184 THE RELATIONSHIP OF BONE MINERAL DENSITY AND VITAMIN K IN RENAL TRANSPLANT PATIENTS

Abstract

Abstract Background and Aims Kidney transplantation is the best treatment for end-stage renal disease (ESRD). Osteoporosis is a common health problem in kidney transplant recipients. It is known that the risk of bone fracture increases by 30% in the first 3 years after transplantation in kidney transplant recipients. Vitamin K is a cofactor involved in the activation of osteocalcin. This protein plays a role in bone mineralization. Currently, vitamin K cannot be measured directly from blood samples, and markers such as proteins induced in the absence of vitamin K (PIVKA-II) and undecarboxylated osteocalcin (ucOC) are used for indirect measurement of vitamin K. In our study, we aimed to investigate the relationship between vitamin K and osteoporosis by measuring serum PIVKA-II, ucOC and BMD in kidney transplant recipients. Method It was a cross-sectional observational study. Patients were selected from kidney transplant patients over 18 years old. A control group was formed from dialysis patients over the age of 18. For vitamin K levels, PIVKA-II and ucOC levels were measured in serum samples taken from patients. The relationship between vitamin K markers, bone mineral densitometry and the risk of major osteoporotic fracture calculated by FRAX in kidney transplant patients was evaluated. Results 68 kidney transplant patients and 20 dialysis patients followed in our clinic were included in this study. As results, it was observed the increased risk of osteoporosis in postmenopausal women patients related with decreased serum vitamin K level (r = −0.520, p = 0.047). Of the transplant group, PIVKA-II and Lumbar I-IV BMD values were statistically significant (p = 0.034, r = -0.258). PIVKA-II was found to be a risk factor for low BMD by multiple linear regression analysis in the transplant group (beta coefficient = −0.195, p = 0.037). Conclusion In our study, it has been proven that as the vitamin K level decreases in kidney transplant patients, the vertebral bone mineral density decreases while the risk of osteoporosis increases. This result shows that vitamin K replacement may have positive effects on bone metabolism.