Irritable bowel syndrome symptom severity improves equally with probiotic and placebo

Abstract

AIMTo determine the effects of Lactobacillus acidophilus NCFM on irritable bowel syndrome (IBS) symptoms and quality of life (QoL).METHODSIn this randomized triple-blind trial, adult IBS volunteers who were recruited according to Rome III criteria received 109 or 1010 colony-forming units of NCFM or placebo daily for 12 wk. IBS Symptom Severity Score (IBS-SSS), which constituted the primary outcome, and secondary outcomes, including individual IBS symptoms, IBS-related QoL questionnaire, anxiety and depression, defecation frequency, and stool consistency, were assessed at baseline at the end of the 8-wk run-in period, after 4 and 12 wk of intervention, and after a 4-wk washout.RESULTSA total of 340 of 391 randomized volunteers completed the trial. IBS-SSS improved over 12 wk of treatment in all treatment groups, decreasing by a mean ± SD of 44.0 ± 80.2, 50.8 ± 82.4, and 48.3 ± 72.2 in the placebo, active low-dose, and active high-dose groups, respectively. Similarly, secondary outcomes did not differ between treatment groups. However, in a post hoc analysis of volunteers with moderate to severe abdominal pain at baseline (VAS > 35/100), the treatment significantly reduced the sensation of abdominal pain. Pain scores fell by 20.8 ± 22.8, 29.4 ± 17.9, and 31.2 ± 21.9 in the placebo, active low-dose, and active high-dose groups, respectively (P value for placebo vs combined active doses = 0.0460).CONCLUSIONNCFM alleviates moderate to severe abdominal pain, consistent with earlier observations of this strain mitigating visceral pain through increased analgesic receptor expression.

Efficacy of probiotics on anxiety-A meta-analysis of randomized controlled trials

“…However, as shown in the forest plot of the metaanalysis, most of the included RCTs also did not find significant difference between probiotics and placebo in alleviating anxiety. This is intriguing because some of the other studies (Guyonnet et al, 2007;Lyra et al, 2016;Ostlund-Lagerstrom et al, 2016) with much larger sample sizes produced nonsignificant findings. This is intriguing because some of the other studies (Guyonnet et al, 2007;Lyra et al, 2016;Ostlund-Lagerstrom et al, 2016) with much larger sample sizes produced nonsignificant findings.…”

“…With respect to the findings, three studies (Kato-Kataoka et al, 2016;Lorenzo-Zuniga et al, 2014;Pinto-Sanchez et al, 2017) found significant difference between the probiotics and control groups in relieving anxiety, whereas the other nine studies (Begtrup et al, 2013;Feher et al, 2014;Guyonnet et al, 2007;Lyra et al, 2016;Marcos et al, 2004;Ostlund-Lagerstrom et al, 2016;Romijn et al, 2017;Steenbergen et al, 2015;Stevenson et al, 2014) found no significant difference between the two groups. The duration of intervention ranged from 4 weeks to 24 weeks.…”

“…Among all the psychiatric symptoms, emotional symptoms, especially anxiety symptoms, are the most ideal targets of probiotics because anxiety is closely related to GI symptoms, such as stomachaches, constipation, or diarrhea (Haug, Mykletun, & Dahl, 2002). For example, some studies reported (Guyonnet et al, 2007;Lorenzo-Zuniga et al, 2014;Silk, Davis, Vulevic, Tzortzis, & Gibson, 2009;Williams et al, 2009) that probiotics are superior to placebo in alleviating anxiety, while others (Begtrup, de Muckadell, Kjeldsen, Christensen, & Jarbol, 2013;Lyra et al, 2016;Simren et al, 2010;Stevenson, Blaauw, Fredericks, Visser, & Roux, 2014) found no significant difference between probiotics and placebo. Thus, with the above theoretical basis derived from the findings of animal studies, many clinical trials have been implemented to test the effect of probiotics on anxiety either in healthy subjects or in subjects with mental or physical illness.…”

“…The remaining 12(Begtrup et al, 2013;Feher et al, 2014;Guyonnet et al, 2007;Kato-Kataoka et al, 2016;Lorenzo-Zuniga et al, 2014;Lyra et al, 2016;Marcos et al, 2004;Ostlund-Lagerstrom et al, 2016;Pinto-Sanchez et al, 2017;Romijn, Rucklidge, Kuijer, & Frampton, 2017;Steenbergen, Sellaro, van Hemert, Bosch, & Colzato, 2015;Stevenson et al, 2014) studies were included in the quantitative meta-analyses. After removing duplicate results, there remained 1,050 studies, of which 1,010 were subsequently excluded in the title and abstract screening step.…”

“…. Two studies(Lorenzo-Zuniga et al, 2014;Lyra et al, 2016) had two active probiotic groups with different dosages (high or low dose). Most studies recruited a higher proportion of women than men except for three studies (one[Kato-Kataoka et al, 2016] had a slightly higher proportion of men and the other two[Feher et al, 2014;Marcos et al, 2004] did not report information about the sex ratio of included subjects).…”