Effects of Probiotics on Autism Spectrum Disorder in Children: A Systematic Review and Meta-Analysis of Clinical Trials

Abstract

Many studies have explored the efficacy of probiotics on autism spectrum disorder (ASD) in children, but there is no consensus on the curative effect. This systematic review and meta-analysis aimed to comprehensively investigate whether probiotics could improve behavioral symptoms in children with ASD. A systematic database search was conducted and a total of seven studies were included in the meta-analysis. We found a nonsignificant overall effect size of probiotics on behavioral symptoms in children with ASD (SMD = −0.24, 95% CI: −0.60 to 0.11, p = 0.18). However, a significant overall effect size was found in the subgroup of the probiotic blend (SMD = −0.42, 95% CI: −0.83 to −0.02, p = 0.04). Additionally, these studies provided limited evidence for the efficacy of probiotics due to their small sample sizes, a shorter intervention duration, different probiotics used, different scales used, and poor research quality. Thus, randomized, double-blind, and placebo-controlled studies following strict trial guidelines are needed to precisely demonstrate the therapeutic effects of probiotics on ASD in children.

Probiotics, prebiotics, and synbiotics for patients with autism spectrum disorder: a meta-analysis and umbrella review

“…( n = 7,450 participants) teenagers and kids and 18 RCTs ( n = 1,104) in adults that were conducted in several worldwide databases by Siafis et al ( 20 ). He et al ( 17 ) did a similar meta-analysis to examine if probiotics might ameliorate behavioral indicators in children with ASD. They found seven papers that supported this hypothesis.…”

“…Moreover, a complete evaluation of the existing literature via an umbrella review reveals a scarcity of comprehensive meta-analyses investigating the simultaneous efficacy of probiotics, prebiotics, and synbiotics for patients diagnosed with ASD. Despite a few metaanalyses, the scope of these analyses is restricted due to the inclusion of only a small number of papers for pooled analyses (15)(16)(17)(18)(19)(20)(21)(22). For this reason, it's crucial to expand the scope of the literature review to incorporate additional studies on the advantages of combining probiotics, prebiotics, and synbiotics for children with ASD.…”

Nutritional Intervention as a Complementary Neuroprotective Approach against Propionic Acid-Induced Neurotoxicity and Associated Biochemical Autistic Features in Rat Pups

“…In assumption, several clinical trials have hypothesized that prebiotics and probiotics might lessen GI symptoms in kids with ASD by raising the relative abundance of helpful bacteria there. Lactobacillus has been shown to ease GI symptoms, which may be connected to the butyric acid in its metabolites [ 48 ]. Excitingly, a combination of the flavonoids luteolin and quercetin appeared to be beneficial in reducing ASD symptoms in children while having no major negative effects [ 49 ].…”

Between Dysbiosis, Maternal Immune Activation and Autism: Is There a Common Pathway?

“…More high-quality studies on children are needed to examine the therapeutic effects of probiotics. Although animal studies seem to give great evidence of improving ASD-like symptoms, there are significant differences between mice and humans, that must be taken into consideration such as species dissimilarity, the drug’s role in inducing ASD model in mice, and complex pathomechanism of ASD in humans [ 287 ].…”