title: Low Dietary Intake of Vitamin D and Vitamin D Deficiency in Hemodialysis Patients.
abstract: BACKGROUND
  The purpose of this study was to test the hypothesis that decreased dietary intake of Vitamin D contributes to Vitamin D deficiency in end-stage renal disease (ESRD) patients on hemodialysis (HD).
  
  
  METHODS
  We performed a cross-sectional study of 58 hemodialysis outpatients from two Mount Sinai Medical Center (MSMC)-affiliated outpatient HD units in New York City and 648 outpatients at MSMC with CKD stages I-IV. Serum 25(OH)D concentrations were measured from August 2010 to July of 2011 in recruited hemodialysis patients (n=58) and linked with results of dietary and lifestyle surveys. The Mount Sinai Data Warehouse (electronic medical record) was used to capture 25(OH) Vitamin D levels for outpatients with CKD stages I-IV who had Vitamin D testing during the same time period.
  
  
  RESULTS
  The prevalence of Vitamin D insufficiency/deficiency in the HD cohort was 96.6%. Mean (SD) and median (IQR) 25(OH)D concentrations were 15.65 (6.82) and 13.55 (10.15) ng/mL, respectively. Dietary surveys showed a median weekly Vitamin D intake of 1044 IU (IQR=808, vs. a recommended weekly allowance of 4200 IU) and specific avoidance of foods containing both Vitamin D and phosphorus. In contrast, mean and median 25(OH)D concentrations in patients with CKD stages I-IV were 25.66 (13.44) and 23.60 (15.48) ng/mL (p<0.001 vs. HD patients).
  
  
  CONCLUSIONS
  Vitamin D deficiency is more prevalent in HD patients than in pre-dialysis patients with CKD and is associated with decreased dietary intake of Vitamin D. Dialysis restrictions imposed to reduce dietary phosphorus intake likely contributes to the development of hypovitaminosis D in ESRD patients.
authors: Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, USA.
authors: Maria
authors: M
authors: Krassilnikova
authors: Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, USA.
authors: Katya
authors: K
authors: Ostrow
authors: Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, USA.
authors: Amanda
authors: A
authors: Bader
authors: Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, USA.
authors: Peter
authors: P
authors: Heeger
authors: Division of Nephrology, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, USA.
authors: Anita
authors: A
authors: Mehrotra
keywords: Hemodialysis diet; Phosphorus; Vitamin D deficiency