The impact of pretransplant 25-hydroxy vitamin D deficiency on subsequent graft function: An observational study
1 Department of Internal Medicine, Wonkwang University College of Medicine Sanbon Hospital, Gunpo-si, Kyunggi-do, Korea
2 Department of Internal Medicine, Yonsei University College of Medicine, 134 Shinchon-dong, Seodaemun-gu, Seoul, 120-752, Korea
3 Department of Surgery, Yonsei University College of Medicine, Seoul, Korea
4 The Research Institute for Transplantation, Yonsei University College of Medicine, Seoul, Korea
BMC Nephrology 2012, 13:22 doi:10.1186/1471-2369-13-22Published: 25 April 2012
In addition to its canonical role in musculoskeletal health, several reports have demonstrated that serum vitamin D level may influence kidney function. However, the effect of pretransplant serum vitamin D level on subsequent graft function has not been explored. Therefore, this study was undertaken to examine the effect of serum vitamin D level at the time of kidney transplantation (KT) on subsequent graft function.
We analyzed 106 patients who underwent KT and for whom 25-hydroxy vitamin D (25-OHD) levels were measured during hospitalization prior to transplantation. We measured estimated glomerular filtration rates (eGFR) using the Modification of Diet in Renal Disease (MDRD) formula at baseline and at six-month intervals up to 36 months after KT.
38.7% of the patients were diagnosed with 25-OHD deficiency defined as less than 10 ng/mL. Recipient gender (female vs. male, odds ratio [OR] 3.30, 95% CI 1.33-8.21, P = 0.010), serum albumin level (per 1 mg/dl increase, OR 0.35, 95% CI 0.13-0.98, P = 0.047), and predominant renal replacement therapy modality before KT (P < 0.001) were found to be independent pretransplant risk factors for 25-OHD deficiency by multivariate logistic regression analysis. Subsequent repeated measures analysis of covariance revealed that 25-OHD level had the only significant main effect on eGFR during the 36-month follow-up period [F (1, 88) = 12.07, P = 0.001].
Pretransplant 25-OHD deficiency was significantly associated with a lower post-transplant eGFR, suggesting that 25-OHD may play an important role in maintaining graft function after KT.