Wolf Myles, Thadhani Ravi
Renal Unit, Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114, USA.
Semin Dial. 2005 Jul-Aug;18(4):302-6. doi: 10.1111/j.1525-139X.2005.18406.x.
Secondary hyperparathyroidism is a common complication of end-stage renal disease (ESRD) that is often treated with activated forms of intravenous vitamin D. The natural course and treatment of secondary hyperparathyroidism in hemodialysis patients is punctuated by episodes of hypercalcemia, hyperphosphatemia, and increased calcium-phosphate product, which in previous studies were linked to increased mortality. Historically these episodes have been attributed to vitamin D, leading some authorities to favor decreased vitamin D use. However, the studies that examined the impact of mineral levels and parathyroid hormone (PTH) on survival did not consistently account for vitamin D therapy itself on hemodialysis patient survival. The current review examines in detail two recent large-scale studies of hemodialysis patients: one that demonstrated a survival advantage of paricalcitol over calcitriol and a second that demonstrated a significant survival advantage of any intravenous vitamin D formulation versus none. In both studies, the effects were independent of mineral and PTH levels, suggesting "nontraditional" actions of vitamin D contributed to the observed survival advantage. Several of these nontraditional actions are reviewed with an emphasis on those that might impact hemodialysis outcomes.
继发性甲状旁腺功能亢进是终末期肾病（ESRD）的常见并发症，通常采用静脉注射活性维生素D进行治疗。血液透析患者继发性甲状旁腺功能亢进的自然病程和治疗过程中会出现高钙血症、高磷血症以及钙磷乘积增加等情况，在以往研究中这些情况与死亡率增加有关。从历史上看，这些情况一直被归因于维生素D，导致一些权威人士倾向于减少维生素D的使用。然而，那些研究矿物质水平和甲状旁腺激素（PTH）对生存率影响的研究并没有始终考虑维生素D治疗本身对血液透析患者生存率的影响。本综述详细研究了两项近期针对血液透析患者的大规模研究：一项研究表明帕立骨化醇比骨化三醇具有生存优势，另一项研究表明任何静脉注射维生素D制剂相对于不使用具有显著的生存优势。在这两项研究中，这些影响均独立于矿物质和PTH水平，这表明维生素D的“非传统”作用促成了观察到的生存优势。本文回顾了其中一些非传统作用，重点关注那些可能影响血液透析结果的作用。
