Key Laboratory for Clinical Cardiovascular Genetics & Sino-German Laboratory for Molecular Medicine, Cardiovascular Institute & FuWai Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
Am J Clin Nutr. 2010 Feb;91(2):480-6. doi: 10.3945/ajcn.2009.28203. Epub 2009 Nov 18.
The effect of isoflavone on endothelial function in postmenopausal women is controversial.
The objective of this study was to evaluate the effect of oral isoflavone supplementation on endothelial function, as measured by flow-mediated dilation (FMD), in postmenopausal women.
A meta-analysis of randomized placebo-controlled trials was conducted to evaluate the effect of oral isoflavone supplementation on endothelial function in postmenopausal women. Trials were searched in PubMed, Embase, the Cochrane Library database, and reviews and reference lists of relevant articles. Summary estimates of weighted mean differences (WMDs) and 95% CIs were obtained by using random-effects models. Meta-regression and subgroup analyses were performed to identify the source of heterogeneity.
A total of 9 trials were reviewed in the present meta-analysis. Overall, the results of the 9 trials showed that isoflavone significantly increased FMD (WMD: 1.75%; 95% CI: 0.83%, 2.67%; P = 0.0002). Meta-regression analysis indicated that the age-adjusted baseline FMD was inversely related to effect size. Subgroup analysis showed that oral supplementation of isoflavone had no influence on FMD if the age-adjusted baseline FMD was > or = 5.2% (4 trials; WMD: 0.24%; 95% CI: -0.94%, 1.42%; P = 0.69). This improvement seemed to be significant when the age-adjusted baseline FMD levels were <5.2% (5 trials; WMD: 2.22%; 95% CI: 1.15%, 3.30%; P < 0.0001), although significant heterogeneity was still detected in this low-baseline-FMD subgroup.
Oral isoflavone supplementation does not improve endothelial function in postmenopausal women with high baseline FMD levels but leads to significant improvement in women with low baseline FMD levels.
异黄酮对绝经后女性的血管内皮功能的影响是有争议的。
本研究旨在评估口服异黄酮补充剂对绝经后女性血管内皮功能（通过血流介导的扩张（FMD）测量）的影响。
对随机安慰剂对照试验进行了荟萃分析，以评估口服异黄酮补充剂对绝经后女性血管内皮功能的影响。在 PubMed、Embase、Cochrane 图书馆数据库以及相关文章的综述和参考文献中进行了试验搜索。使用随机效应模型获得加权均数差（WMD）和 95%置信区间（CI）的汇总估计值。进行了荟萃回归和亚组分析，以确定异质性的来源。
本荟萃分析共纳入了 9 项试验。总体而言，9 项试验的结果表明，异黄酮显著增加了 FMD（WMD：1.75%；95%CI：0.83%，2.67%；P=0.0002）。荟萃回归分析表明，年龄调整后的基线 FMD 与效应大小呈负相关。亚组分析表明，如果年龄调整后的基线 FMD 大于等于 5.2%（4 项试验；WMD：0.24%；95%CI：-0.94%，1.42%；P=0.69），口服异黄酮补充剂对 FMD 没有影响。当年龄调整后的基线 FMD 水平较低（<5.2%，5 项试验；WMD：2.22%；95%CI：1.15%，3.30%；P<0.0001）时，这种改善似乎是显著的，但在这个低基线 FMD 亚组中仍存在显著的异质性。
口服异黄酮补充剂不能改善高基线 FMD 水平的绝经后女性的血管内皮功能，但可显著改善低基线 FMD 水平的女性的血管内皮功能。
