School of Public Health, Anhui Medical University, 81 Mei Shan Road, Hefei 230032, Anhui, China.
J Bone Miner Metab. 2012 Jan;30(1):60-8. doi: 10.1007/s00774-011-0287-3. Epub 2011 Jun 15.
A number of randomized controlled trials (RCTs) examining the role of vitamin K on bone mineral density (BMD) have yielded inconsistent results. We performed a meta-analysis of these trials to assess the effect of vitamin K on BMD. We searched MEDLINE, EMBASE and CENTRAL for relevant studies of RCTs examining the role of vitamin K on BMD. Data on participants, interventions, and outcomes were extracted and the quality of all included trials assessed. Primary outcomes for analysis were absolute changes in BMD (mg/cm(2)) at the lumbar spine and femoral neck. Relative changes (percentage change) in BMD at the lumbar spine were also assessed. Vitamin K supplementation was shown to be efficacious in increasing BMD at the lumbar spine but not the femoral neck. The weighted mean difference (WMD) in BMD absolute change was 21.60 mg/cm(2) [95% confidence interval (CI) 3.63, 39.56] at the lumbar spine and 0.25 mg/cm(2) (95% CI -2.64, 3.14) at the femoral neck. The WMD in BMD relative change was 1.27% (95% CI 0.47, 2.06) at the lumbar spine and 0.17 (95% CI -0.21, 0.54) at the femoral neck. Subgroup analysis revealed that ethnic difference, gender, and vitamin K type were associated with variable effects on BMD at the lumbar spine. The modest overall treatment effects for vitamin K on BMD observed in this review may be biased and should be interpreted with caution. Further studies are required to address factors relating to the observed effects of vitamin K on BMD.
多项随机对照试验（RCT）研究了维生素 K 对骨密度（BMD）的作用，但结果不一致。我们对这些试验进行了荟萃分析，以评估维生素 K 对 BMD 的影响。我们检索了 MEDLINE、EMBASE 和 CENTRAL 以获取有关 RCT 研究维生素 K 对 BMD 作用的研究。提取了参与者、干预措施和结局的数据，并评估了所有纳入试验的质量。分析的主要结局是腰椎和股骨颈 BMD 的绝对变化（mg/cm²）。还评估了腰椎 BMD 的相对变化（百分比变化）。维生素 K 补充剂可有效增加腰椎 BMD，但对股骨颈 BMD 无效。腰椎 BMD 绝对变化的加权均数差（WMD）为 21.60 mg/cm²（95%置信区间 3.63，39.56），股骨颈为 0.25 mg/cm²（95%置信区间 -2.64，3.14）。腰椎 BMD 相对变化的 WMD 为 1.27%（95%置信区间 0.47，2.06），股骨颈为 0.17%（95%置信区间 -0.21，0.54）。亚组分析显示，种族差异、性别和维生素 K 类型与腰椎 BMD 的不同影响有关。本综述中观察到的维生素 K 对 BMD 的总体治疗效果可能存在偏差，应谨慎解释。需要进一步的研究来解决与维生素 K 对 BMD 观察到的影响有关的因素。
