Relationship between serum 1,25-dihydroxyvitamin D and mortality in patients with pre-dialysis chronic kidney disease

Clin Exp Nephrol. 2008 Apr;12(2):126-131. doi: 10.1007/s10157-007-0023-4. Epub 2008 Jan 9.


Background: It is known that vitamin D has many functions besides involvement in calcium metabolism. It has recently been recognized that vitamin D deficiency is associated with mortality, especially in cardiovascular disease (CVD). Vitamin D deficiency is common in end-stage renal disease, but develops from the early stage of chronic kidney disease (CKD). So we investigated whether the serum level of the activated form of vitamin D (1,25-dihydroxyvitamin D) affected mortality in patients with CKD stages 3 and 4.

Methods: Between January 1, 1995, and June 30, 2006 we measured serum 1,25-dihydroxyvitamin D In 226 patients with CKD stages 3 and 4 and classified the results into two groups depending on whether the level was below (group I) or above (group II) 20 pg/ml. We ended the follow-up period on December 31, 2006. We compared all-cause and cardiovascular mortality between the two groups. We also examined predictors of mortality by using Cox proportional regression analysis.

Results: Two-hundred and twenty-six patients (67 men and 159 women, mean age 67.0) were registered in this study, and groups 1 and 2 comprised 84 and 142 patients, respectively. During the follow-up period 43 patients died. CVD was the major cause of death, followed by infectious disease. The Kaplan-Meier survival curve revealed that all-cause mortality was significantly higher in group I, but a significant difference between CVD mortality in the two groups was not demonstrated. By Cox proportional regression analysis, group I was related to all-cause mortality, but this was not proved to be an independent predictor.

Conclusion: The results suggested that serum level of 1,25-dihydroxyvitamin D was associated with all-cause mortality in patients with CKD stages 3 and 4.

Publication types

  • Comparative Study

MeSH terms

  • Aged
  • Biomarkers / blood
  • Cardiovascular Diseases / blood*
  • Cardiovascular Diseases / etiology
  • Cardiovascular Diseases / mortality*
  • Communicable Diseases / blood
  • Communicable Diseases / etiology
  • Communicable Diseases / mortality
  • Disease Progression
  • Female
  • Follow-Up Studies
  • Humans
  • Kaplan-Meier Estimate
  • Male
  • Middle Aged
  • Prognosis
  • Proportional Hazards Models
  • Renal Insufficiency, Chronic / blood*
  • Renal Insufficiency, Chronic / complications
  • Renal Insufficiency, Chronic / mortality*
  • Risk Assessment
  • Severity of Illness Index
  • Time Factors
  • Vitamin D / analogs & derivatives*
  • Vitamin D / blood
  • Vitamin D Deficiency / blood*
  • Vitamin D Deficiency / complications
  • Vitamin D Deficiency / mortality*


  • Biomarkers
  • Vitamin D
  • 1,25-dihydroxyvitamin D