The effect of encapsulated probiotic on Attention Deficit Hyperactivity Disorder: A Randomized Controlled Trial

Attention Deficit Hyperactivity Disorder (ADHD) is one of the most common mental disorders in children and adolescents. Probiotics supplementation may help to modification of gut microbiome and consequently improve some ADHD symptoms. Thus, this study aimed to assess effect of probiotic supplementation on ADHD patients aged ۴-۱۶ years. In this study ۶۰ Iranian ADHD children were randomly assigned to receive encapsulated Lactobacillus plantarum PTCC ۱۸۹۶™ (A۷) and Bifidobacterium animalis subsp. Lactis (BB-۱۲®) probiotic pearls or placebo for ۸ weeks. Assessment of ADHD symptoms was conducted using Conners' Parent Rating Scale (CPRS) and Integrated Visual and Auditory Continues Performance Test (IVA/CPT) at baseline and the end of study. There was no significant difference in the CPRS total score and its subscales between two groups. A significant higher score was observed in auditory response control in the probiotic group versus the placebo group at the endpoint (probiotic group: ۹۱.۵۵ ± ۱۶.۶۹; placebo group: ۸۰.۵۵ ± ۱۷.۴۳; p= ۰.۰۲). Furthermore, hyperactivity/impulsivity symptoms were improved among five patients in the probiotic group (p=۰.۰۶). Probiotic supplementation may have some beneficial effects on some outcomes related to ADHD such as auditory response control. Improvement of hyperactivity/impulsivity symptoms in some patients in the probiotic group along with improving in auditory response control in this group may be recommended a beneficial effect of probiotic supplement on hyperactivity/impulsivity symptoms and not inattentive part in ADHD.