Servicio de Nefrología, IIS-Fundacion Jimenez Diaz and IRSIN, Madrid, Spain.
Clin Exp Nephrol. 2012 Dec;16(6):945-51. doi: 10.1007/s10157-012-0642-2. Epub 2012 May 29.
There are seasonal variations in serum 25-hydroxyvitamin D (25OHD) levels related to sun exposure. Recent guidelines suggest a target serum 25OHD level >30 ng/ml in chronic kidney disease patients. However, vitamin D supplementation dosing and monitoring regimens are not well established in hemodialysis patients. The aim of this study was to assess the interplay between season and 25OHD supplementation according to guidelines on 25OHD levels in hemodialysis patients.
We retrospectively reviewed data collected prospectively over 12 months in 32 stable hemodialysis patients receiving 25OHD supplements (mean dose 30,600 IU/month) under routine clinical care following the Spanish Society of Nephrology guidelines.
Higher serum 25OHD was observed during the summer, peaking in June and August. Despite a trend towards a higher 25OHD dose in winter the prevalence of 25OHD deficiency was still >40 % in winter. Furthermore, despite a higher dose of calcium-based phosphate binders, there was a trend toward lower serum calcium in winter. Season, together with residual diuresis and dry weight, was a significant independent contributor to a multivariate lineal regression model that explained 25 % of serum 25OHD variability, while a 25OHD dose did not contribute significantly in this 25OHD-supplemented population.
Winter vitamin D deficiency is prevalent in hemodialysis patients despite supplementation with 25OHD according to clinical guidelines. More intensive monitoring or pre-emptive winter dose increases should be evaluated to achieve guideline targets.
血清 25-羟维生素 D（25OHD）水平与阳光暴露有关，存在季节性变化。最近的指南建议慢性肾脏病患者的血清 25OHD 目标水平>30ng/ml。然而，血液透析患者的维生素 D 补充剂量和监测方案尚未得到很好的确立。本研究旨在根据血液透析患者的 25OHD 水平指南评估季节和 25OHD 补充之间的相互作用。
我们回顾性分析了 32 例稳定血液透析患者的数据，这些患者在接受西班牙肾脏病学会指南指导下的常规临床护理时，每月接受 25OHD 补充剂（平均剂量 30600IU/月），共 12 个月。
血清 25OHD 在夏季较高，6 月和 8 月达到峰值。尽管冬季 25OHD 剂量有升高趋势，但冬季 25OHD 缺乏的患病率仍>40%。此外，尽管钙基磷酸盐结合剂的剂量较高，但冬季血清钙有下降趋势。季节、残余尿量和干体重是多元线性回归模型的一个重要独立因素，该模型解释了 25OHD 变异性的 25%，而在这个接受 25OHD 补充的人群中，25OHD 剂量并没有显著贡献。
尽管根据临床指南补充了 25OHD，但血液透析患者在冬季仍普遍存在维生素 D 缺乏。应评估更密集的监测或预防性冬季剂量增加，以达到指南目标。
