Abstract: TH-PO198
Hepcidin, Iron Indices, and Bone Mineral Metabolism in Non-Dialysis CKD
Session Information
- Bone and Mineral Metabolism: Clinical - I
October 25, 2018 | Location: Exhibit Hall, San Diego Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Bone and Mineral Metabolism
- 402 Bone and Mineral Metabolism: Clinical
Authors
- Lee, Sung Woo, Eulji General Hospital, Seoul, Korea (the Republic of)
- Sung, Su Ah, Eulji Medical Center, Seoul, Korea (the Republic of)
Background
There have been some small studies which have reported that intravenous iron replacement was associated with levels of bone mineral metabolism markers. Disordered bone mineral metabolisms are also well-known risk factors of erythropoietin (EPO) resistance. Hepcidin is a key peptide for the EPO resistance and iron metbolism. Although the intimate association between hepcidin, iron indices, and bone mineral metabolism was expected, particularly in non-dialysis chronic kidney disease (CKD) patients, it has been studied sparsely. Therefore, we performed this study.
Methods
We reviewed data of 2,238 patients from a large-scale multicenter prospective Korean study (2,011–2,016), and excluded 214 patients with missing data on markers and related-medications of iron and bone mineral metabolism, hemoglobin, blood pressure and causes of CKD. Multivariate linear regression analysis was used to identify the association between iron and bone mineral metabolism.
Results
The proportion of CKD stage 1-5 were 16.2%, 18.7%, 37.1%, 21.6%, and 6.4%, respectively. Per each 10% increase in transferrin saturation (TSAT), there was a 0.013 mmol/l decrease in phosphorus [95% confidence interval (CI) -0.021–-0.004; P = 0.003] and a 0.022 nmol/l increase in logarithmic 25-hydroxyvitamin D (Ln-25OHD) levels (95% CI 0.005–0.040; P = 0.019). A 1 pmol/l increase in Ln-ferritin was associated with a 0.080 ng/l decrease in Ln-intact parathyroid hormone (Ln-iPTH) (95% CI -0.122–-0.039; P <0.001). Meanwhile, beta (95% CI) per 1 unit increase in phosphorus, Ln-25OHD, and Ln-iPTH for the square root of the serum hepcidin were 0.594 (0.257–0.932; P= 0.001), -0.270 (-0.431–-0.108; P = 0.001), and 0.115 (0.004–0.226; P = 0.042), respectively. In subgroup analysis, the relationship between phosphorus, 25OHD, and hepcidin was strongest in the positive-inflammation group.
Conclusion
Increased TSAT was associated with decreased and increased phosphorus and 25OHD levels, respectively, while increased ferritin was associated with decreased iPTH levels. Increased phosphorus and iPTH and decreased 25OHD were independently associated with increased hepcidin levels.