Efficacy of prebiotic, probiotic and synbiotic administration in improving growth in children aged 0-59 months living in low- and middle-income countries: a systematic review and meta-analysis.

backgroundPoor growth is one of the major obstacles to human development, affecting millions of children under the age of 5 years, particularly those living in low- and middle-income countries (LMICs). The objective of this review was to evaluate the efficacy of administering pre-, pro- or synbiotics on the growth of children aged 0-59 months living in LMICs.

methodsGoogle scholar, Pubmed, clinical trial.org and Science Direct databases were searched in April 2023 for randomised controlled trials of pre-, pro- or synbiotics that evaluated growth in under fives in LMICs. The primary outcome were weight and height gain. Secondary outcomes were head circumference, body mass index gain and Z score. Random-effects meta-analysis was used to calculate mean differences for continuous outcomes. Grading of Recommendations Assessment, Development and Evaluation criteria was used to assess certainty of the evidence.

resultsEight trials involving 1375 children under 5 years of age were identified. Meta-analysis of 6 RCTs (n = 991 children) revealed a significant difference in favor of the experimental group (n = 579) compared the control group (n = 412) for weight gain: (MD = 0.33 kg, 95% CI 0.11 to 0.55); low-certainty evidence. Sub-group analysis revealed that pre-, pro, or synbiotics may be more effective in malnourished that healthy children (p = 0.003). Meta-analysis of height gain for 4 RCTs (n = 845) found that there was no significant difference between the experimental group (n = 496) and the control group (n = 349) (MD = 0.31 cm; 95% CI -0.36 to 0.98); low-certainty evidence. In sub-group analysis, prebiotics had a greater impact on height gain than synbiotics (p = 0.03). In the only study reporting an increase in head circumference (n = 32 children), this was not improved by the administration of synbiotics. However, administration of synbiotics to undernourished children significantly improved BMI gain.

conclusionThe evidence for the administration of pre-, pro- or synbiotics on the growth of children in LMICs is weak. Administration of pre-, pro- or synbiotics may improve weight gain in both healthy and malnourished children. Prebiotics and synbiotics had a significant effect on weight gain. Further research is needed due to the small number of studies, short duration of administration and small sample size.