Rawan Almutairi1, Abigail Raffner Basson2,3, Fabio Cominelli2,3,4, Pamela Wearsh1, Alexander Rodriguez-Palacios5,6,7,8. 1. Department of Pathology, Case Western Reserve University, 2109 Adelbert Road, Cleveland, OH, 44106, USA. 2. Department of Medicine and Division of Gastroenterology & Liver Diseases, Case Western Reserve University School of Medicine, Cleveland, OH, USA. 3. Digestive Health Research Institute, University Hospitals Cleveland Medical Center, Cleveland, OH, USA. 4. University Hospitals Research and Education Institute, University Hospital Cleveland Medical Center, Cleveland, OH, USA. 5. Department of Medicine and Division of Gastroenterology & Liver Diseases, Case Western Reserve University School of Medicine, Cleveland, OH, USA. axr503@case.edu. 6. Digestive Health Research Institute, University Hospitals Cleveland Medical Center, Cleveland, OH, USA. axr503@case.edu. 7. Germ-Free and Gut Microbiome Core, Cleveland Digestive Diseases Research Core Center, Case Western Reserve University, 2109 Adelbert Road, Cleveland, OH, USA. axr503@case.edu. 8. University Hospitals Research and Education Institute, University Hospital Cleveland Medical Center, Cleveland, OH, USA. axr503@case.edu.
Abstract
PURPOSE: Maltodextrin (MDX) is a polysaccharide food additive commonly used as oral placebo/control to investigate treatments/interventions in humans. The aims of this study were to appraise the MDX effects on human physiology/gut microbiota, and to assess the validity of MDX as a placebo-control. METHODS: We performed a systematic review of randomized-placebo-controlled clinical trials (RCTs) where MDX was used as an orally consumed placebo. Data were extracted from study results where effects (physiological/microbial) were attributed (or not) to MDX, and from study participant outcomes data, before-and-after MDX consumption, for post-publication 're-analysis' using paired-data statistics. RESULTS: Of two hundred-sixteen studies on 'MDX/microbiome', seventy RCTs (n = 70) were selected for analysis. Supporting concerns regarding the validity of MDX as a placebo, the majority of RCTs (60%, CI 95% = 0.48-0.76; n = 42/70; Fisher-exact p = 0.001, expected < 5/70) reported MDX-induced physiological (38.1%, n = 16/42; p = 0.005), microbial metabolite (19%, n = 8/42; p = 0.013), or microbiome (50%, n = 21/42; p = 0.0001) effects. MDX-induced alterations on gut microbiome included changes in the Firmicutes and/or Bacteroidetes phyla, and Lactobacillus and/or Bifidobacterium species. Effects on various immunological, inflammatory markers, and gut function/permeability were also documented in 25.6% of the studies (n = 10/42). Notably, there was considerable variability in the direction of effects (decrease/increase), MDX dose, form (powder/pill), duration, and disease/populations studied. Overall, only 20% (n = 14/70; p = 0.026) of studies cross-referenced MDX as a justifiable/innocuous placebo, while 2.9% of studies (n = 2/70) acknowledged their data the opposite. CONCLUSION: Orally-consumed MDX often (63.9% of RCTs) induces effects on human physiology/gut microbiota. Such effects question the validity of MDX as a placebo-control in human clinical trials.
PURPOSE: Maltodextrin (MDX) is a polysaccharide food additive commonly used as oral placebo/control to investigate treatments/interventions in humans. The aims of this study were to appraise the MDX effects on human physiology/gut microbiota, and to assess the validity of MDX as a placebo-control. METHODS: We performed a systematic review of randomized-placebo-controlled clinical trials (RCTs) where MDX was used as an orally consumed placebo. Data were extracted from study results where effects (physiological/microbial) were attributed (or not) to MDX, and from study participant outcomes data, before-and-after MDX consumption, for post-publication 're-analysis' using paired-data statistics. RESULTS: Of two hundred-sixteen studies on 'MDX/microbiome', seventy RCTs (n = 70) were selected for analysis. Supporting concerns regarding the validity of MDX as a placebo, the majority of RCTs (60%, CI 95% = 0.48-0.76; n = 42/70; Fisher-exact p = 0.001, expected < 5/70) reported MDX-induced physiological (38.1%, n = 16/42; p = 0.005), microbial metabolite (19%, n = 8/42; p = 0.013), or microbiome (50%, n = 21/42; p = 0.0001) effects. MDX-induced alterations on gut microbiome included changes in the Firmicutes and/or Bacteroidetes phyla, and Lactobacillus and/or Bifidobacterium species. Effects on various immunological, inflammatory markers, and gut function/permeability were also documented in 25.6% of the studies (n = 10/42). Notably, there was considerable variability in the direction of effects (decrease/increase), MDX dose, form (powder/pill), duration, and disease/populations studied. Overall, only 20% (n = 14/70; p = 0.026) of studies cross-referenced MDX as a justifiable/innocuous placebo, while 2.9% of studies (n = 2/70) acknowledged their data the opposite. CONCLUSION: Orally-consumed MDX often (63.9% of RCTs) induces effects on human physiology/gut microbiota. Such effects question the validity of MDX as a placebo-control in human clinical trials.
Authors: Nathaniel D Fastinger; Lisa K Karr-Lilienthal; Julie K Spears; Kelly S Swanson; Krista E Zinn; Gerardo M Nava; Kazuhiro Ohkuma; Sumiko Kanahori; Dennis T Gordon; George C Fahey Journal: J Am Coll Nutr Date: 2008-04 Impact factor: 3.169
Authors: Evelyne M Dewulf; Patrice D Cani; Sandrine P Claus; Susana Fuentes; Philippe G B Puylaert; Audrey M Neyrinck; Laure B Bindels; Willem M de Vos; Glenn R Gibson; Jean-Paul Thissen; Nathalie M Delzenne Journal: Gut Date: 2012-11-07 Impact factor: 23.059