Georgia Prevention Institute, Department of Pediatrics, Medical College of Georgia, Augusta, USA.
Am J Hypertens. 2011 May;24(5):557-62. doi: 10.1038/ajh.2011.12. Epub 2011 Feb 10.
A growing body of evidence has linked vitamin D deficiency to increased risk of cardiovascular disease. Vitamin D deficiency is also more common in African Americans for whom an increased cardiovascular disease risk exists. This study sought to test the hypothesis that 16 weeks of 60,000 IU monthly supplementation of oral vitamin D(3) would improve flow-mediated dilation (FMD) in African Americans, whereas no change would be observed in the placebo group.
A randomized, double-blind, placebo-controlled clinical trial was conducted. Fifty-seven African-American adults were randomly assigned to either the placebo group or vitamin D group.
Following 16 weeks of placebo (n = 23; mean age 31 ± 2 years) or 60,000 IU monthly oral vitamin D(3) (n = 22; mean age 29 ± 2 years), serum concentrations of 25-hydroxyvitamin D (25(OH)D) increased from 38.2 ± 3.0 to 48.7 ± 3.2 nmol/l and 34.3 ± 2.2 to 100.9 ± 6.6 nmol/l, respectively. No changes in serum parathyroid hormone (PTH), serum calcium, or urine calcium/creatinine were observed following either treatment. Following 16 weeks of treatment, significant improvements in FMD were only observed in the vitamin D group (1.8 ± 1.3%), whereas the placebo group had no change (-1.3 ± 0.6%). Similarly, the vitamin D group exhibited an increase in absolute change in diameter (0.005 ± 0.004 cm) and FMD/shear (0.08 ± 0.04 %/s(-1), area under the curve (AUC) × 10(3)) following treatment, whereas no change (-0.005 ± 0.002 cm and -0.02 ± 0.02 %/s(-1), AUC, respectively) was observed following placebo.
Supplementation of 60,000 IU monthly oral vitamin D(3) (~2,000 IU/day) for 16 weeks is effective at improving vascular endothelial function in African-American adults.
越来越多的证据表明维生素 D 缺乏与心血管疾病风险增加有关。维生素 D 缺乏在非裔美国人中也更为常见，而他们的心血管疾病风险更高。本研究旨在检验以下假设：即口服维生素 D（3）60,000IU 每月补充剂 16 周将改善非裔美国人的血流介导的扩张（FMD），而安慰剂组则不会观察到变化。
进行了一项随机、双盲、安慰剂对照的临床试验。57 名非裔美国成年人被随机分配到安慰剂组或维生素 D 组。
经过 16 周的安慰剂（n = 23；平均年龄 31 ± 2 岁）或 60,000IU 每月口服维生素 D（3）（n = 22；平均年龄 29 ± 2 岁）治疗后，血清 25-羟维生素 D（25（OH）D）浓度分别从 38.2 ± 3.0 增加到 48.7 ± 3.2 nmol/L 和 34.3 ± 2.2 到 100.9 ± 6.6 nmol/L。两种治疗均未观察到甲状旁腺激素（PTH）、血清钙或尿钙/肌酐的变化。治疗 16 周后，仅在维生素 D 组观察到 FMD 显著改善（1.8 ± 1.3%），而安慰剂组无变化（-1.3 ± 0.6%）。同样，维生素 D 组在直径的绝对变化（0.005 ± 0.004cm）和 FMD/剪切（0.08 ± 0.04%/s(-1)，曲线下面积（AUC）×10(3)）方面也表现出增加，而安慰剂组无变化（-0.005 ± 0.002cm 和-0.02 ± 0.02%/s(-1)，AUC 分别）。
补充 60,000IU 每月口服维生素 D（3）（~2,000IU/天）16 周可有效改善非裔美国成年人的血管内皮功能。
