Lack of evidence for administering vitamin D analogs to kidney failure patients to improve survivability.
BACKGROUND
The Kidney Disease Outcome Quality Initiative (K/DOQI) Bone Metabolism Guidelines recommend the use of active vitamin D analogs for the treatment of secondary hyperparathyroid bone disorder in end-stage renal disease (ESRD); however, the effect of vitamin D therapy on the mortality of ESRD patients has not yet been tested in randomized controlled trials. A 2005 publication entitled "Activated Injectable Vitamin D and Hemodialysis Survival: A Historical Cohort Study" claimed ESRD patients receiving injectable vitamin D had a survival advantage. In an effort to validate that conclusion, this author reviewed the publicly-available data of the US Renal Data System (USRDS) and other published reports to evaluate if the use of vitamin D analogs has been shown to be effective in the past decade in improving ESRD patient survival.


METHODS
A review, examination, and comparison of the data extracted from the USRDS were made for the period of 1992 - 2002 which covered Medicare ESRD patients in terms of vitamin D administration and mortality. Other pertinent studies were reviewed in the same way.


RESULTS
This critical review revealed that scientific evidence for the administration of injectable vitamin D is insufficient in this cohort study as the design flaws inherently diminish the significance of their findings. The annual mortality rate in US Medicare hemodialysis patients has remained unchanged despite the dramatic increase in the percent of these patients receiving injectable vitamin D, which suggests that vitamin D analog therapy does not improve survivability in ESRD patients.


CONCLUSIONS
The potentially harmful consequences of excessive vitamin D analog dosing should caution nephrologists and other CKD health professionals against the off-label use of vitamin D analogs for improved survivability in ESRD patients until additional randomized controlled studies/trials are done and the effects made clear. This review emphasizes the need for additional research to further elucidate the role of vitamin D in the treatment and mortality of ESRD patients.
Cantor
T L
TL
Scantibodies Laboratory, Inc., Santee, CA 92071, USA. tom.cantor@scantibodies.com
D050071:Bone Density Conservation Agents / Q000008:administration & dosage*; D006801:Humans; D006962:Hyperparathyroidism, Secondary / Q000150:complications; D007676:Kidney Failure, Chronic / Q000150:complications / Q000401:mortality*; D010024:Osteoporosis / Q000209:etiology / Q000517:prevention & control*; D012307:Risk Factors; D015996:Survival Rate / Q000639:trends; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology; D014807:Vitamin D / Q000008:administration & dosage / Q000031:analogs & derivatives*
D050071:Bone Density Conservation Agents; D014807:Vitamin D