Vitamin D and Arteriovenous Fistulae
Condition: End-stage Renal Disease
MeSH terms: Kidney Failure, Chronic; Arteriovenous Fistula; Fistula
Study type: Interventional

Summary: 
      Patients requiring hemodialysis following kidney failure need a form of dialysis vascular
      access in order to undergo the dialysis procedure. Dialysis vascular access dysfunction is an
      enormous clinical problem. While the best form of vascular access is the arteriovenous
      fistula (AVF), its primary problem is early, aggressive cellular ingrowth that leads to poor
      maturation of the vessel, preventing its use for dialysis. Strategies to prevent AVF failure
      are needed.

      Vitamin D is a hormone present in all human bodies and is important for good bone formation
      and immune function. There is new information that links vitamin D to the function of our
      veins and arteries, which are used in the creation of an arteriovenous fistulae. Our bodies
      can make vitamin D and can also get vitamin D from our diet. However, a majority of patients
      with chronic kidney disease and end-stage renal disease (ESRD) have low vitamin D levels
      (vitamin D deficiency). There are several benefits to correcting low vitamin D levels,
      however, it is not know whether correcting low vitamin D in the body will lead to better
      function of the vein and artery used for arteriovenous fistulae creation. The main goal of
      this pilot study is to examine the role of vitamin D supplementation on AVF maturation and
      useability for dialysis. Study results will be used to develop larger studies to examine the
      specific effect that vitamin D supplementation has on the vessels used for AVF creation and
      whether vitamin D promotes AVF maturation.
    

Detailed description: 
      Hemodialysis vascular access dysfunction is a major source of morbidity and cost among ESRD
      patients, accounting for up to 25% of all hospital stays, and 50% of all costs within the
      first year of initiating dialysis.The AVF provides higher blood flow rates, fewer thrombotic
      and infectious complications, and lower morbidity and cost compared with prosthetic grafts or
      central venous catheters.However,up to 50% of newly created AVF's fail to mature sufficiently
      for chronic hemodialysis use. Clearly, determining factors predictive of poor AVF maturation
      are important from both patient care and health policy perspectives and are worthy of
      investigation.

      Vitamin D has antiproliferative, antioxidant and antiangiogenic properties. The observed
      association of vitamin D deficiency and increased risk of cardiovascular and peripheral
      vascular disease may extend to the vasculature used in the creation of an AVF.

      As renal function worsens, patients with chronic kidney disease (CKD) produce less vitamin D,
      due to impaired renal conversion of 25-hydroxy- to 1,25-dihydroxyvitamin D by declining renal
      1-alpha hydroxylase. As a result, at the time of dialysis initiation,78%-90% of ESRD patients
      are vitamin D deficient. Until recently, vitamin D deficiency among CKD and ESRD patients was
      only treated if hyperparathyroidism was present, however, more attention is now paid to
      nutritional vitamin D deficiency given its association with a range of comorbid
      conditions.Furthermore, 1,25-dihydroxyvitamin D and its analogue compounds are associated
      with improved survival in the CKD and ESRD populations. We believe that the observed benefits
      of vitamin D may improve AVF maturation among a population in which vitamin D deficiency is
      highly prevalent.
    

Intervention name(s): Vitamin D3; Placebo
Intervention type(s): Drug; Drug
Intervention description(s): Vitamin D3 200,000 IU once a week for 3 weeks; Placebo one time per week for 3 weeks
Intervention MeSH terms: Vitamin D; Cholecalciferol
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: ESRD; Vitamin D; Arteriovenous Fistulae; Dialysis Vascular Access