Vitamin D Supplementation on Physical and Cognitive Function-Pilot Study

描述（由申请人提供）： 血液透析（HD）患者循环中1，25-OH维生素D水平降低，因为其主要生产部位是通过1-α羟化酶的健康肾脏。缺乏症在透析时用静脉注射1，25-OH活性维生素D治疗，滴定以达到国家肾脏基金会（NKF）肾透析结果质量倡议（KDOQI）指南推荐的目标甲状旁腺激素（PTH）值。尽管有这些静脉维生素D治疗，HD患者25-OH维生素缺乏症的患病率非常高。在非透析人群中，25-OH缺乏症与神经肌肉功能和认知能力差相关。目前尚不清楚维生素25-OH D缺乏在HD患者经历的高度普遍的肌无力和认知障碍中的作用。由于肾脏以外的许多组织具有能够将25 OH维生素D活化为1-25 OH维生素D的1-α羟化酶，因此仅针对PTH范围给予IV活性维生素D可能完全忽略其他骨骼外组织上的重要维生素D。我们研究的主要目的是确定维生素D补充对25-OH维生素D水平< 20 ng/ml的HD患者神经肌肉和认知功能的影响。我们提出一项前瞻性、随机、[双盲安慰剂对照]试验。入组的受试者将以2：1的比例随机接受维生素D（n=20）或[安慰剂]（n=10）治疗6个月。在基线神经肌肉和认知评估后，治疗组将每两周接受50，000 IU口服麦角钙化醇，持续6个月，并每月重新测量25（OH）维生素D3水平。补充维生素D 6个月后，将进行神经肌肉和认知评估。将分析[安慰剂]组和治疗组之间的神经肌肉功能和认知评估结果，以及两组6个月间隔前后的评估差异。

DESCRIPTION (provided by applicant): Hemodialysis (HD) patients have reduced circulating levels of 1,25-OH vitamin D levels because its major site of production is the healthy kidney via the 1-alpha hydroxylase enzyme. The deficiency is treated with intravenous1,25-OH active vitamin D at dialysis which is titrated to achieve a targeted parathyroid hormone (PTH) value recommended by the National Kidney Foundation (NKF) Kidney Dialysis Outcomes Quality Initiative (KDOQI) Guidelines. Despite these intravenous vitamin D treatments, HD patients have a very high prevalence of 25-OH vitamin deficiency. 25-OH deficiency has been associated with poor neuromuscular function and cognition in non-dialysis populations. The role vitamin 25-OH D deficiency in the highly prevalent muscle weakness and cognitive impairment experienced by HD patients is currently not known. Since many tissues other than the kidney possess the 1-alpha hydroxylase enzyme capable of activating 25 OH vitamin D to 1-25 OH vitamin D, administering IV active vitamin D solely to target a PTH range may completely neglect important vitamin D on other extra-skeletal tissues. The primary goal of our study is to determine the effect of vitamin D supplementation on neuromuscular and cognitive function in HD patients with 25-OH vitamin D levels < 20 ng/ml. We propose a prospective, randomized, [double-blind placebo controlled] trial. Enrolled participants will be randomized 2:1 to receive vitamin D (n=20) or [placebo] (n=10) for 6 months. Following baseline neuromuscular and cognitive assessments, the treatment group will receive 50,000 IU of oral ergocalciferol every two weeks for 6 months, and have 25(OH) vitamin D3 levels re-measured at monthly intervals. Following 6 months of vitamin D supplementation, neuromuscular and cognitive assessments will be performed. Results from neuromuscular function and cognitive assessments between the [placebo] arm and treatment will be analyzed as well as differences in assessments prior to and following the 6 month interval in both groups.