Science

Anna Pärtty, Marko Kalliomäki, Pirjo Wacklin, Seppo Salminen & Erika Isolauri

Background:
Recent experimental evidence suggests that gut microbiota may alter function within the nervous system providing new insight on the mechanism of neuropsychiatric disorders.
Methods:
75 infants who were randomized to receive Lactobacillus rhamnosus GG (ATCC 53103) or placebo during the first six months of life were followed-up for 13 years. Gut microbiota was assessed at the age of 3 weeks, 3, 6, 12, 18, 24 months and 13 years using FISH and qPCR, and indirectly by determining the blood group secretor type at the age of 13 years. The diagnoses of attention deficit hyperactivity disorder (ADHD) and Asperger syndrome (AS) by a child neurologist or psychiatrist were based on ICD-10 diagnostic criteria.
Results:
At the age of 13 years ADHD or AS was diagnosed in 6/35 (17.1%) children in the placebo and none in the probiotic group (p=0.008). The mean (SD) numbers of Bifidobacterium species bacteria in feces during the first six months of life was lower in affected children 8.26 (1.24)log cells/g than in healthy children 9.12 (0.64) log cells/g; p=0.03.
Conclusion:
Probiotic supplementation early in life may reduce the risk of neuropsychiatric disorder development later in childhood possible by mechanisms not limited to gut microbiota composition.