Impact of probiotic supplements on behavioural and gastrointestinal symptoms in children with autism spectrum disorder: A randomised controlled trial

Abstract

Objective To investigate whether probiotic supplementation can improve behavioural and gastrointestinal (GI) symptoms in children with autism spectrum disorder (ASD) aged 2-9 years and further explore the correlation between these symptoms. Design Single-blinded, randomised, placebo-controlled study. Setting Five developmental paediatric outpatient clinics of 'Continua Kids'. Patients Children aged 2-9 years diagnosed with ASD along with their caregivers. Interventions Probiotic or placebo sachet reconstituted in 50 mL of lukewarm milk/water, taken two times per day for 3 months. Main outcome measures Change in behavioural (measured by Social Responsiveness Scale-2 (SRS-2) and Aberrant Behaviour Checklist-2 (ABC-2) tools) and GI (measured by GI Severity Index (GSI) score) symptoms after receiving intervention for 3 months. Results A total of 180 children with ASD were enrolled in the study (probiotic group: 90 and placebo group: 90). All children completed the study. The probiotic group showed a significant reduction in behavioural symptom severity as measured by the SRS-2 tool (47.77% vs 23.33%; p=0.000) compared with the placebo. Probiotic-treated children demonstrated significant reductions in severe symptoms, including social withdrawal/lethargy (40%), stereotypic behaviour (37.77%), hyperactivity (34.44%) and inappropriate speech (32.22%) post-intervention (p=0.000). They also had marked improvements in constipation (p=0.003) and diarrhoea (p=0.043) compared with the placebo group. Both groups exhibited a statistically significant correlation between behavioural and GI symptoms. Conclusions Probiotic supplementation improved behavioural and GI symptoms in children with ASD with no adverse effects. Both symptoms were significantly correlated. However, these results need to be validated in a larger sample size.