Efficacy of Probiotics on Anxiety: A Meta-analysis of Randomized Controlled Trials

Abstract

Objective:Anxiety is a common, burdensome, and psychologically important global concern. However, probiotics may be useful for the treatment of anxiety. Methods:To assess the effects of probiotics on anxiety, seven academic databases were searched for reports published in the English language. Results:Based on our search, 10 studies were identified. Probiotics significantly decreased anxiety compared to controls (mean difference [MD], 0.66; 95% confidence interval [CI], 0.41 to 0.92; P < 0.001). However, significantly lower DASS values were reported of -9.87 (95%CI, -17.2 to -2.47; P < 0.009). Conclusions:Our report showed that probiotics decrease anxiety values in populations with anxiety. These results are important for the management of anxiety. In the future, more adequately powered RCTs using standardized measurements are required to assess the specific probiotics and dosages as well as the treatment periods that are most beneficial for anxiety.

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

“…Our findings are also different from that of three previously published meta-analyses (Huang et al, 2017;Huang, Wang, & Hu, 2016;McKean, Naug, Nikbakht, Amiet, & Colson, 2017) assessing the effect of probiotics on depression, anxiety, or psychological symptoms. The inconsistency in findings between our study and the meta-analysis of Huang et al (2017) is particularly interesting because we addressed the same topic but found very different results. The main reason for this discrepancy may arise from the difference in the outcome indexes between the two studies.…”

“…The inconsistency in findings between our study and the meta-analysis of Huang et al (2017) is particularly interesting because we addressed the same topic but found very different results. In the study of Huang et al (2017), the authors included only studies using validated anxiety assessment scales, resulting in exclusion of some studies (Feher et al, 2014;Lorenzo-Zuniga et al, 2014) using author-made scales, which are included in our meta-analysis. In the study of Huang et al (2017), the authors included only studies using validated anxiety assessment scales, resulting in exclusion of some studies (Feher et al, 2014;Lorenzo-Zuniga et al, 2014) using author-made scales, which are included in our meta-analysis.…”

“…The main reason for this discrepancy may arise from the difference in the outcome indexes between the two studies. Moreover, Huang et al (2017) used the total scores, Hospital Anxiety and Depression Scale (HADS) or Depression Anxiety Stress Scales (DASS), for data analysis, which might bring significant bias in outcome assessment because these scales measured not only anxiety, but also depression and stress symptoms. Moreover, Huang et al (2017) used the total scores, Hospital Anxiety and Depression Scale (HADS) or Depression Anxiety Stress Scales (DASS), for data analysis, which might bring significant bias in outcome assessment because these scales measured not only anxiety, but also depression and stress symptoms.…”

“…In addition, the methods used for data synthesis in the study of Huang et al (2017) are also open to discussion. In our study, the disadvantages of the meta-analysis of Huang et al (2017) were avoided by using the scores of anxiety subscales of HADSA, DASS, and healthrelated quality of life (HRQoL), and using "random-effect model" for data synthesis when the heterogeneity between included studies was high. In our study, the disadvantages of the meta-analysis of Huang et al (2017) were avoided by using the scores of anxiety subscales of HADSA, DASS, and healthrelated quality of life (HRQoL), and using "random-effect model" for data synthesis when the heterogeneity between included studies was high.…”

“…In the study of Huang et al (2017), the authors included only studies using validated anxiety assessment scales, resulting in exclusion of some studies (Feher et al, 2014;Lorenzo-Zuniga et al, 2014) using author-made scales, which are included in our meta-analysis. Moreover, Huang et al (2017) used the total scores, Hospital Anxiety and Depression Scale (HADS) or Depression Anxiety Stress Scales (DASS), for data analysis, which might bring significant bias in outcome assessment because these scales measured not only anxiety, but also depression and stress symptoms. In addition, the methods used for data synthesis in the study of Huang et al (2017) are also open to discussion.…”