Therapeutic efficacy of probiotics for symptoms of attention-deficit hyperactivity disorder in children and adolescents: meta-analysis
Shun-Chin Liang,
Cheuk-Kwan Sun,
Chih-Hua Chang,
Yu-Shian Cheng,
Ruu-Fen Tzang,
Hsien-Jane Chiu,
Ming Yu Wang,
Ying-Chih Cheng,
Kuo-Chuan Hung
Affiliations
Shun-Chin Liang
Department of Management Center, Jianan Psychiatric Center, Ministry Of Health and Welfare, Taiwan; Department of Center for General Education, University of Kun Shan, Taiwan; and Department of Optometry, University of Chung Hwa of Medical Technology, Taiwan
Cheuk-Kwan Sun
Department of Emergency Medicine, E-Da Dachang Hospital, I-Shou University, Taiwan; and School of Medicine for International Students, College of Medicine, I-Shou University, Taiwan
Chih-Hua Chang
Department of Psychiatry, Tsyr-Huey Mental Hospital, Kaohsiung Jen-Ai's Home, Taiwan
Yu-Shian Cheng
Department of Psychiatry, Tsyr-Huey Mental Hospital, Kaohsiung Jen-Ai's Home, Taiwan
Department of Psychiatry, Mackay Memorial Hospital, Taiwan
Hsien-Jane Chiu
Taoyuan Psychiatric Center, Ministry of Health and Welfare, Taiwan; and Institute of Hospital and Health Care Administration, National Yang-Ming University, Taiwan
Ming Yu Wang
Department of Psychiatry, China Medical University Hsinchu Hospital, China Medical University, Taiwan; and Department of Health Services Administration, China Medical University, Taiwan
Ying-Chih Cheng
Department of Psychiatry, China Medical University Hsinchu Hospital, China Medical University, Taiwan; Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taiwan; and Research Center of Big Data and Meta-analysis, Wan Fang Hospital, Taipei Medical University, Taiwan
Background The efficacy of probiotics as a therapeutic alternative for attention-deficit hyperactivity disorder (ADHD) remain unclear. Aims To investigate the effectiveness of probiotics for symptoms of ADHD and identify possible factors affecting their efficacy. Method Randomised placebo-controlled trials were identified through searching major databases from inception to April 2023, using the main keywords ‘probiotics’ and ‘ADHD’ without limitation on languages or geographic locations. The outcome of interest included improvement in total symptoms of ADHD, symptoms of inattention and hyperactivity/impulsivity, and drop-out rate. Continuous and categorical data were expressed as effect sizes based on standardised mean differences (SMDs) and odds ratios, respectively, with 95% confidence intervals. Results Meta-analysis of seven trials involving 379 participants (mean age 10.37 years, range 4–18 years) showed no significant improvement in total symptoms of ADHD (SMD = 0.25; P = 0.12), symptoms of inattention (SMD = 0.14; P = 0.3) or hyperactivity/impulsivity (SMD = 0.08; P = 0.54) between the probiotic and placebo groups. Despite non-significance on subgroup analyses, there was a large difference in effect size between studies using probiotics as an adjunct to methylphenidate and those using probiotics as supplementation (SMD = 0.84 v. 0.07; P = 0.16), and a moderate difference in effect size between studies using multiple strains of probiotics and those using single-strain regimens (SMD = 0.45 v. 0.03; P = 0.19). Conclusions Current evidence shows no significant difference in therapeutic efficacy between probiotics and placebos for treatment of ADHD symptoms. However, albeit statistically non-significant, higher therapeutic efficacies associated with multiple-strain probiotics or combining probiotics with methylphenidate may provide direction for further research.
