Department of Family Medicine, Georgetown University Medical Center, 240 Building D, 4000 Reservoir Road NW, Washington, DC 20007-2145, USA.
Department of Mathematics, UPMC, St. Margaret Hospital, Duquesne University, Pittsburgh, PA, USA.
Br J Nutr. 2014 Jan 28;111(2):279-86. doi: 10.1017/S0007114513002237. Epub 2013 Oct 8.
The present study investigated the effect of Bifidobacterium animalis ssp. lactis Bf-6 (LMG 24 384) (Bf-6)-supplemented yogurt on colonic transit time (CTT). A triple-blinded, randomised, placebo-controlled, two-period cross-over trial was conducted with sixty-eight women with a self-reported history of straining during bowel movements or hard or lumpy stools in the past 2 years. As per regulatory requirements for probiotic studies, eligible women were generally healthy and not actively constipated at the time of enrolment. Participants consumed both Bf-6 and placebo yogurts for 14 d each in a randomised order, with a 6-week washout period between the treatments. The primary outcome, CTT, was assessed via Sitz marker X-rays. The average CTT was 42·1 h for the active period and 43·3 h for the control period (mean difference 1·2 h, 95 % CI - 4·9, 7·4). Since the statistical tests for the cross-over study implied that the mean CTT for the active and control periods in period 2 were biased, the standard protocol suggests examining the results of only period 1 as a traditional randomised controlled trial. This showed that the mean CTT was 35·2 h for the active period v. 52·9 h for the control period (P= 0·015). Bootstrapping demonstrated that both the mean and median differences remained significant (P= 0·016 and P= 0·045, respectively). Few adverse events were noted, with no differences among the active and control periods. The paired analysis showed no differences between the active and control periods during the cross-over trial. Further trials should be conducted in populations with underlying problems associated with disordered transit to determine the potential value of probiotic supplementation more accurately.
本研究探讨了双歧杆菌动物亚种。 lactis Bf-6（LMG 24384）（Bf-6）-补充酸奶对结肠传输时间（CTT）的影响。一项三盲、随机、安慰剂对照、两周期交叉试验纳入了 68 名女性，这些女性在过去 2 年中有排便时用力、硬便或块状便的自述史。根据益生菌研究的监管要求，合格的女性通常在入组时身体健康，没有明显的便秘。参与者随机先后食用 Bf-6 和安慰剂酸奶各 14 天，两种处理之间有 6 周洗脱期。主要结局指标 CTT 通过坐标记 X 射线评估。活跃期的平均 CTT 为 42.1 h，对照组为 43.3 h（平均差异 1.2 h，95%CI-4.9，7.4）。由于交叉研究的统计检验表明活跃期和对照组在第 2 期的平均 CTT 存在偏倚，标准方案建议仅将第 1 期作为传统的随机对照试验进行检查。结果显示，活跃期的平均 CTT 为 35.2 h，对照组为 52.9 h（P=0.015）。自举法表明，平均和中位数差异均保持显著（P=0.016 和 P=0.045）。报告的不良事件很少，活跃期和对照组之间无差异。交叉试验的配对分析显示，活跃期和对照组之间无差异。应在存在与转运障碍相关的潜在问题的人群中进行进一步试验，以更准确地确定益生菌补充的潜在价值。
