Vitamin D Supplementation in Kidney Disease
Condition: Renal Dialysis; Vitamin D Deficiency
MeSH terms: Vitamin D Deficiency
Study type: Interventional

Summary: 
      This is a double-blind placebo controlled pilot study to determine if vitamin D
      supplementation in hemodialysis (HD) patients will improve physical function and cognition.
      HD patients have a high prevalence of vitamin D deficiency, cognitive impairment, and
      physical impairment. Despite standard clinical care with active IV vitamin D during dialysis,
      HD patients still have markedly low levels of nutritional or dietary vitamin D. IV treatment
      with vitamin D during dialysis is aimed at treating HD related bone disease. Recent
      literature shows that oral or nutritional vitamin D has multiple extra-skeletal effects
      including improvement in cognition and physical function. In this study, the investigators
      plan to administer oral vitamin D to vitamin D deficient HD patients already receiving
      standard care with IV vitamin D therapy. Patients will be randomized to receive either
      placebo or 50,000 IU of vitamin D (cholecalciferol) weekly for 6 months. The investigators'
      specific aims are to 1) Assess the benefits of correcting nutritional vitamin D deficiency on
      cognitive and physical function in HD patients receiving routine standard of care, 2) Assess
      the feasibility of recruiting HD patients for this study, and 3) Evaluate the proposed
      regimen for safely and effectively increasing nutritional vitamin D levels with oral
      supplementation. The investigators anticipate that correction of nutritional vitamin D
      deficiency to optimal levels will improve the high prevalence of cognitive impairment and
      physical impairment in this population. These results will be used as evidence to support a
      larger study aimed at treating nutritional vitamin D deficiency in all patients receiving HD.
      These results may also contribute to a change in current guidelines which place little
      emphasis on the monitoring and treatment of nutritional vitamin D levels in HD patients.
      These results are important for the Veteran dialysis population since many of them are
      required to perform high-level cognitive tasks such as management of complex medical regimens
      and physical tasks such as orchestrating independent transportation to and from HD sessions
      and multiple physician appointments.
    

Detailed description: 
      Patients will first be identified based on the inclusion criteria, then informed about the
      study and consented. Those who meet the exclusion criteria will be randomized to treatment or
      placebo. Enrolled participants will be randomized 2:1 to receive vitamin D (n=20) or placebo
      (n=10) for 6 months. All participants will be tested twice over two weeks to establish
      baseline values. Following baseline testing, the treatment group will receive 50,000 IU
      (standard replacement therapy) of oral cholecalciferol or placebo. The initial dose of
      cholecalciferol will be 50,000 IU weekly for 6 weeks. Vitamin D levels will then be measured.
      Participants who still have Vitamin D insufficiency ( 35 ng/ml) will remain on 50,000 IU of
      cholecalciferol for another 6 weeks, at which point Vitamin D levels will be measured again.
      Participants who reach 25-OH levels > 35 ng/ml will have their dosing regimen lessened to
      10,000 IU weekly (maintenance dose) for the remainder of the 6 months. Participants receiving
      placebo will start taking the placebo maintenance dose after the first 6 weeks. For safety
      monitoring, 25(OH) vitamin D3 levels will also be re-measured at monthly intervals and
      followed by an independent medical monitor. In patients who have serum vitamin D levels
      60ng/ml, the frequency of administration will be reduced to once a month. The participants
      will receive supplementation for a total of 6 months. At this time, vitamin D levels will be
      reassessed and participants will undergo follow-up functional assessments, and cognitive and
      immune testing.
    

Intervention name(s): Cholecalciferol (Vitamin D)
Intervention type(s): Dietary Supplement
Intervention description(s): 50,000 units of cholecalciferol or a placebo pill administered once a week for 6 months
Intervention MeSH terms: Vitamin D; Cholecalciferol
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment