Restrepo-Valencia Cesar A, Aguirre-Arango Jose V, Musso Carlos G
Professor Titular, Universidad de Caldas, Manizales, Colombia.
Professor Catedratico, Universidad de Manizales, Manizales, Colombia.
Int J Nephrol Renovasc Dis. 2019 Dec 6;12:241-250. doi: 10.2147/IJNRD.S214194. eCollection 2019.
In a high percentage of patients with chronic kidney disease (CKD) low levels of vitamin D are detected. The purpose of this study was to evaluate if the native vitamin D therapy (cholecalciferol) in the patients with stage 3 and hypovitaminosis D allows to modify markers of bone and mineral metabolism once normal serum levels have been achieved.
From an initial base of 297 patients with CKD and hypovitaminosis D, those with normal or high levels of PTH were chosen for therapy with native vitamin D. The initial administered dose was 1000 IU/day, with adjustments every 4 months of 1000 IU (maximum 4000 IU/day, according to RDA and IOM), until achieving serum levels of 25 hydroxyvitamin D greater than 30 ng/mL and lower than 80 ng/mL. The variables calcium, phosphorus, intact parathormone (iPTH), creatinine and glomerular filtration rate (GFR) were also evaluated every 4 months.
The total number of patients included in this study was 170. Seventy-three patients were excluded along the follow-up: 17 non-responders (never achieved the projected serum levels of vitamin D), and 56 for not completing one year of follow-up. A total of 97 patients were finally included. In 82 patients, follow-up was achieved for 12 months (G1) and in 38 patients for 24 months (G2). In 15 patients despite achieving satisfactory levels of vitamin D at 12 months, it was not possible to obtain adequate levels of iPTH for their GFR according to K/DOQI 2003 guidelines and they were called refractory to therapy (G3). In both groups 1 and 2, a non-significant tendency to increase calcium and serum phosphorus was observed. iPTH decreased significantly at 12 and 24 months follow-up. In group 3, we opted at 12 months for conversion to calcitriol, with a significant reduction in iPTH values. In this group, the initial value of GFR was close to 30 mL/min, and its fall in time more significant than the other two groups to CKD stage 4.
Cholecalciferol with adjustment in its dose, and obtaining normal serum levels is an excellent therapeutic alternative for the treatment of patients with CKD stage 3, and hypovitaminosis D. In the group of patients with GFR close to 30 mL/min, or lower values (stage 4), and with the presence of secondary hyperparathyroidism, the use of active form of vitamin D (calcitriol, paricalcitol) is recommended as the first therapeutic alternative.
在高比例的慢性肾脏病（CKD）患者中检测到维生素D水平较低。本研究的目的是评估对于3期且维生素D缺乏的患者，在血清水平恢复正常后，天然维生素D疗法（胆钙化醇）是否能够改变骨和矿物质代谢指标。
从297例CKD且维生素D缺乏的患者初始样本中，选择甲状旁腺激素（PTH）水平正常或较高的患者接受天然维生素D治疗。初始给药剂量为1000 IU/天，每4个月调整1000 IU（根据美国国家科学院医学研究所（RDA和IOM）标准，最大剂量为4000 IU/天），直至血清25羟维生素D水平高于30 ng/mL且低于80 ng/mL。每4个月还评估钙、磷、全段甲状旁腺激素（iPTH）、肌酐和肾小球滤过率（GFR）等变量。
本研究纳入的患者总数为170例。随访期间排除73例患者：17例无反应者（从未达到预期的维生素D血清水平），56例未完成1年随访。最终共纳入97例患者。82例患者完成12个月随访（G1组），38例患者完成24个月随访（G2组）。15例患者尽管在12个月时维生素D水平达到满意，但根据2003年K/DOQI指南，其GFR对应的iPTH水平未达标，这些患者被称为治疗抵抗（G3组）。在G1组和G2组中，钙和血清磷均有非显著性升高趋势。随访12个月和24个月时，iPTH显著下降。在G3组中，12个月时我们选择换用骨化三醇，iPTH值显著降低。该组患者初始GFR接近30 mL/min，随时间下降至CKD 4期的幅度比其他两组更大。
调整剂量并使血清水平恢复正常的胆钙化醇是治疗3期CKD且维生素D缺乏患者的极佳治疗选择。对于GFR接近30 mL/min或更低值（4期）且存在继发性甲状旁腺功能亢进的患者组，建议首选活性维生素D形式（骨化三醇、帕立骨化醇）进行治疗。
