Exposure to antibiotics in the first 24 months of life and neurocognitive outcomes at 11 years of age.

RATIONALE: Antibiotics are commonly prescribed for infants. In addition to increasing concern about antibiotic resistance, there is a concern about the potential negative impact of antibiotics on the gut microbiota and health and development outcomes. OBJECTIVE: The aim of this study was to investigate the association between early life antibiotic exposure and later neurocognitive outcomes. METHODS: Participants were infants born to mothers enrolled in the probiotics study. The initial study was designed to evaluate the effect of two different probiotics on allergy outcomes in childhood. Antibiotic exposure was based on parent report and categorised according to the following timing of the first exposure: 0-6 months, 6-12 months, 12-24 months or not at all. At 11 years of age, children's neurocognitive outcomes were assessed using psychologist-administered, parent-report and self-report measures. The relationship between the timing of antibiotic exposure and neurocognitive outcomes was examined using regression models. RESULTS: Of the 474 participants initially enrolled, 342 (72%) children had a neurocognitive assessment at 11 years of age. After adjustment for mode of delivery, probiotic treatment group assignment, income and breastfeeding, children who had received antibiotics in the first 6 months of life had significantly lower overall cognitive and verbal comprehension abilities, increased risk of problems with metacognition, executive function, impulsivity, hyperactivity, attention-deficit hyperactivity disorder, anxiety and emotional problems. CONCLUSIONS: These results provide further evidence that early exposure to antibiotics may be associated with detrimental neurodevelopmental outcomes.

Effect of early probiotic supplementation on childhood cognition, behaviour and mood a randomised, placebo-controlled trial.

AIM: To determine whether probiotic supplementation in early life improves neurocognitive outcomes assessed at 11 years of age. METHODS: A total of 474 children who were born March 2004-Aug 2005 participated in a two-centre randomised placebo-controlled trial of infants at risk of developing allergic disease. Pregnant women were randomised to take Lactobacillus rhamnosus strain HN001, Bifidobacterium animalis subsp. lactis strain HN019 or placebo daily from 35 weeks gestation until six months if breastfeeding, and their infants the same treatment from birth to two years. Intelligence, executive function, attention, depression and anxiety were assessed when the children were 11 years of age. RESULTS: A total of 342 (72.2%) children were assessed (HN001 n = 109, HN019 n = 118 and placebo n = 115). Overall, there were no significant differences in the neurocognitive outcomes between the treatment groups. CONCLUSION: HN001 and HN019 given in early life were not associated with neurocognitive outcomes at 11 years of age in this study. However, we cannot exclude that other probiotics may have a beneficial effect. Further clinical trials are indicated.