关于口服双膦酸盐（BP）的摄入量与结直肠癌（CRC）风险之间的关联，最近几项研究得到了比较冲突的结果。为此，本研究收集已发表的一些研究中的证据，进行一个明确的剂量-反应的荟萃分析，研究结果在线发表于JCO 。

　　2012年1月15日，通过搜索MEDLINE和EMBASE数据库纳入相关研究。我们纳入研究报道了口服双膦酸盐和CRC风险之间关联的95%置信区间的效果估计。

　　3个病例对照研究，共16998例CRC和108197对照人群；一个队列研究纳入94405人接受口服双膦酸盐和283181人未接受双膦酸盐被纳入这项荟萃分析。

　　随机效应模型的荟萃分析结果表明：接受口服双膦酸盐的CRC患者的合并风险比（OR）为0.87（95％CI，0.78-0.97）。剂量为10剂及以上与CRC呈显著的负相关，合并OR值为0.71（95％CI，0.58-0.87）。同样，分析表明使用1至3年和超过3年的双膦酸盐使用都呈显著的负相关关系，合并OR值分别为0.76（95％CI，0.68-0.85）和0.78（95％CI，0.61-0.99）。

　　该荟萃分析表明，在10个或更多的处方剂量使用口服双膦酸盐或1年或以上的持续时间的使用都与CRC的风险降低相关。当然还需要进一步的随机对照试验来证明这种关联。

　　Reduced Risk of Colorectal Cancer With Use of Oral Bisphosphonates: A Systematic Review and Meta-Analysis

　　Purpose The association between oral bisphosphonate (BP) intake and colorectal cancer (CRC) risk has been investigated in several recent studies with conflicting results. We summarized the evidence from the published studies in a categorical, dose-response meta-analysis.

　　Methods Relevant studies were identified by a search of MEDLINE and EMBASE databases through January 15, 2012. We included studies that reported effect size estimates with 95% CIs for the association between exposure to oral BPs and risk of CRC.

　　Results Three case-control studies with a total of 16,998 CRC cases and 108,197 controls and one cohort study with 94,405 individuals exposed to BPs and 283,181 unexposed to BPs were included in meta-analysis. The random effect model meta-analysis suggested reduced risk of CRC with exposure to oral BPs with pooled odds ratio (OR) of 0.87 (95% CI, 0.78 to 0.97). Significant inverse relationship was noted for 10 or more presc**tions categories, with pooled ORs of 0.71 (95% CI, 0.58 to 0.87). Similarly, the analysis for 1 to 3 years of use and more than 3 years of use of BPs suggested a significant inverse relationship, with pooled ORs of 0.76 (95% CI, 0.68 to 0.85) and 0.78 (95% CI, 0.61 to 0.99), respectively.

　　Conclusion This meta-analysis suggests that the use of oral BPs at a dose of 10 or more presc**tions or 1 or more years of duration is associated with reduced risk of CRC. Further randomized controlled trials are needed to prove this association.