Borgi Lea, McMullan Ciaran, Wohlhueter Ann, Curhan Gary C, Fisher Naomi D, Forman John P
Brigham and Women's Hospital, Renal Division, Department of Medicine, Boston, Massachusetts, USA;
Brigham and Women's Hospital, Renal Division, Department of Medicine, Boston, Massachusetts, USA.
Am J Hypertens. 2017 Feb;30(2):124-129. doi: 10.1093/ajh/hpw135. Epub 2016 Nov 15.
In nonhypertensive individuals, lower levels of 25-hydroxyvitamin D (25[OH]D) have been associated with an increased risk of hypertension, and vitamin D deficiency has been associated with endothelial dysfunction in such individuals. However, the effect of vitamin D supplementation on endothelial dysfunction in nonhypertensive individuals has not been examined in a rigorous fashion.
In this randomized, double-blind, placebo-controlled trial of nonhypertensive, nondiabetic overweight, or obese individuals with vitamin D deficiency (body mass index ≥25 and 25[OH]D ≤ 20 ng/ml), we assigned subjects to receive either ergocalciferol (50,000 units) or matching placebo, once a week for 8 weeks. Our primary outcome was endothelial-dependent vasodilation (EDV) measured by brachial artery ultrasound at baseline and 8 weeks postrandomization.
By the end of the trial, 46 and 47 participants were allocated to receive ergocalciferol and placebo, respectively. Mean 25(OH)D levels increased from 14.9 to 30.3 in the vitamin D group and 14.4 to 17.4 in the placebo. EDV did not change significantly with either vitamin D repletion (from 6.3 ± 3.6% at baseline to 6.1 ± 4.6% at 8 weeks; P value = 0.78) or placebo (7.9 ± 4.7% to 6.8 ± 4.7%; P = 0.17). The treatment effect P value (comparing the 8-week change with ergocalciferol to the change with placebo) was 0.35.
In this randomized, double-blind, placebo-controlled trial, there was no improvement in endothelial function (measured as EDV) after repletion of vitamin D in overweight/obese nonhypertensive individuals.
在非高血压个体中，25-羟维生素D（25[OH]D）水平较低与高血压风险增加相关，且维生素D缺乏与这类个体的内皮功能障碍相关。然而，维生素D补充剂对非高血压个体内皮功能障碍的影响尚未得到严格研究。
在这项针对维生素D缺乏（体重指数≥25且25[OH]D≤20 ng/ml）的非高血压、非糖尿病超重或肥胖个体的随机、双盲、安慰剂对照试验中，我们将受试者分为两组，一组每周一次接受骨化醇（50,000单位），另一组接受匹配的安慰剂，共8周。我们的主要结局是通过肱动脉超声在基线和随机分组后8周测量的内皮依赖性血管舒张（EDV）。
试验结束时，分别有4�和47名参与者被分配接受骨化醇和安慰剂。维生素D组的平均25(OH)D水平从14.9升至30.3，安慰剂组从14.4升至17.4。补充维生素D（从基线时的6.3±3.6%到8周时的6.1±4.6%；P值 = 0.78）或安慰剂（从7.9±4.7%到6.8±4.7%；P = 0.17）后，EDV均无显著变化。治疗效果P值（比较骨化醇8周变化与安慰剂变化）为0.35。
在这项随机、双盲、安慰剂对照试验中，超重/肥胖非高血压个体补充维生素D后内皮功能（以EDV衡量）并无改善。
