Effect of probiotic supplementation on cognitive function in children and adolescents: a systematic review of randomised trials

Abstract

Available reviews have shown potential effects of probiotics on neurobehavioral outcomes through ‘gut-brain axis’ mechanism in adults. However, reviews on cognitive function in children and adolescents are lacking. Therefore, we conducted a systematic review of randomised controlled trials (RCTs) of the effect of probiotic supplementation on cognitive function in children and adolescents. A search of four databases (Cochrane Central Register of Controlled Trials, PsycARTICLES, Scopus, PubMed) was conducted to identify RCTs published from January 1990 to December 2018. Seven studies met the inclusion criteria and their cognitive outcomes were analysed. Only one study found a positive result with Lactobacillus rhamnosus GG (LGG) 1×1010 cfu supplementation with outcomes on attention deficit hyperactivity disorder (ADHD) or Asperger syndrome (AS) manifestations as diagnosed using the International Classification of Diseases-10 criteria. The supplementations were administered to Finnish mothers for 4 weeks before delivery and continuously given for 6 months after delivery if they breastfed, or to the children. ADHD or AS was diagnosed at the age of 13 years in 17.1% children in the placebo and none in the probiotic group (P=0.008). This study found significant differences in species composition and number of cells belonging to the genus Bifidobacterium between healthy children and children who later developed ADHD or AS at different time points. Six remaining studies with varying strains, durations of intervention, start-time of administration, and outcomes demonstrated no difference in cognition after probiotic supplementation. Metagenomic analyses on gut microbiota composition were not performed in any of these studies. In conclusion, the favourable effect of probiotic supplementation on cognitive function in children and adolescents was observed in one study with LGG supplementation by a risk reduction of developing ADHD or AS (i.e. autism). More long-term and follow-up trials using probiotics identifying the effect on cognition are warranted before routine use.

Physicochemical Properties and Sensory Acceptability of a Next-Generation Functional Chocolate Added with Omega-3 Polyunsaturated Fatty Acids and Probiotics

“…For that reason, the addition of probiotic strains such as L. plantarum 299v has been found to improve cognitive functioning in patients with major depression [8]. Additionally, other lactic bacteria such as L. rhamnosus GG have shown improvements in children's and adolescents' cognitive function, generating the reduction of behavior and communication disorders such as autism [9]. Therefore, the development of next-generation functional foods is crucial to make available to consumers products with beneficial health effects [10].…”

Current Evidence on the Role of the Gut Microbiome in ADHD Pathophysiology and Therapeutic Implications

“…A recent systematic review included randomized controlled trials, published between 1990 and 2018, that had evaluated the effects of probiotic supplementation on the cognitive function in children and adolescents. Seven studies were found to meet the inclusion criteria, but only one of them reported a significant reduction in the risk to develop ADHD or ASD [195]. This was a double-blind randomized placebo-controlled trial conducted by Pärtty et al [152] on a Finnish population of 159 infants who had at least one family member with allergic disease.…”

Towards Tailored Gut Microbiome-Based and Dietary Interventions for Promoting the Development and Maintenance of a Healthy Brain

“…To date, there is no evidence on whether gut microbiota-directed interventions can help in ADHD management, although preclinical evidence on gut microbiota-ADHD causality has recently been reported for fecal microbiota transplant in mice ( 103 ). Regarding the potential effects of probiotics on neurobehavioral outcomes in children and adolescents, a recent systematic review reported that prenatal and early infant probiotic supplementation with Lactobacillus rhamnosus GG (LGG) is associated with a lowered abundance of gut Bifidobacteria in infancy, and a decreased risk of developing ADHD ( 104 ).…”

“…Regarding the potential use of probiotic supplementation for ASD prevention, in a recently published review ( 104 ) researchers reported only one study demonstrating that specific probiotic supplementation with Lactobacillus rhamnosus GG during pregnancy and during the first year of life was associated with a reduction in the risk of developing Asperger's syndrome ( 127 ). It is worth noting that the reduction in disease onset risk was coupled with a lowered abundance of gut Bifidobacterium in infancy and, although the mechanisms underlying the benefits of this probiotic supplementation remain unclear, a potential explanation lies in the modulation of gut microbiota composition through probiotic supplementation.…”