A systematic review of the beneficial effects of prebiotics, probiotics, and synbiotics on ADHD

BACKGROUND

Children with attention deficit hyperactivity disorder (ADHD) may benefit from probiotics and prebiotics, but the effects are unclear. To determine whether probiotics and prebiotics affect children with ADHD, a systematic review was conducted.

METHODS

The present systematic review analyzed cohort studies and randomized controlled trials that examined whether prebiotics and probiotics are associated with ADHD. Seven randomized controlled trials and two cohort studies met our inclusion criteria.

RESULTS

Research on Lactobacillus rhamnosus GG (LGG) probiotic supplementation showed that children with ADHD had better emotional, physical, social, and school functioning, and a higher health-related quality of life compared to the placebo group. The studies also showed that Synbiotic 2000 reduces markers of intestinal and vascular inflammation in children with ADHD, in part through increasing SCFA levels.

CONCLUSION

The use of probiotics and prebiotics as adjuvants therapy in patients with ADHD is beneficial. Further studies with longer duration, including more participants and a variety of age groups, and using various evaluation techniques such as in vivo observation are required to examine the effects of prebiotics and probiotics on ADHD.

Probiotics in the critically ill: a systematic review of the randomized trial evidence

OBJECTIVE

Critical illness results in changes to the microbiology of the gastrointestinal tract, leading to a loss of commensal flora and an overgrowth of potentially pathogenic bacteria. Administering certain strains of live bacteria (probiotics) to critically ill patients may restore balance to the microbiota and have positive effects on immune function and gastrointestinal structure and function. The purpose of this systematic review was to evaluate the effect of probiotics in critically ill patients on clinical outcomes.

DESIGN

Systematic review.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We searched computerized databases, reference lists of pertinent articles, and personal files from 1980 to 2011. We included randomized controlled trials enrolling critically ill adults, which evaluated probiotics compared to a placebo and reported clinically important outcomes (infections, mortality, and length of stay). A total of 23 randomized controlled trials met inclusion criteria. Probiotics were associated with reduced infectious complications as documented in 11 trials (risk ratio 0.82; 95% confidence interval 0.69-0.99; p = .03; test for heterogeneity p = .05; I 44%). When data from the seven trials reporting ventilator-associated pneumonia were pooled, ventilator-associated pneumonia rates were also significantly reduced with probiotics (risk ratio 0.75; 95% confidence interval 0.59-0.97; p = .03; test for heterogeneity p = .16; I 35%). Probiotics were associated with a trend toward reduced intensive care unit mortality (risk ratio 0.80; 95% confidence interval 0.59-1.09; p = .16; test for heterogeneity p = .89; I 0%) but did not influence hospital mortality. Probiotics had no effect on intensive care unit or hospital length of stay. Compared to trials of higher methodological quality, greater treatment effects were observed in trials of a lower methodological quality.

CONCLUSIONS

Probiotics appear to reduce infectious complications including ventilator-associated pneumonia and may influence intensive care unit mortality. However, clinical and statistical heterogeneity and imprecise estimates preclude strong clinical recommendations. Further research on probiotics in the critically ill is warranted.

The use of pre- pro- and synbiotics in adult intensive care unit patients: systematic review

BACKGROUND & AIMS

This review investigated whether the administration of enteral pre-, pro- and synbiotics compared with controls in adult intensive care unit (ICU) patients reduced the incidence of nosocomial infections, length of ICU stay, hospital mortality and specifically pneumonia.

METHODS

Systematic review of randomised controlled trials comparing enteral feeding and pre-, pro- or synbiotics, versus standard enteral feed alone, in patients admitted to adult ICUs.

RESULTS

Eight randomised studies with a total of 999 critically ill adult patients met the inclusion criteria. Pre- pro- or synbiotics were not associated with any significant change in the outcomes studied-length of ICU stay, hospital mortality and the incidence of nosocomial infection and more specifically pneumonia incidence. Few data were available for other outcomes.

CONCLUSIONS

The use of pre- pro- or synbiotics in adult critically ill patients confers no statistically significant benefit in the outcome criteria studied. There is currently a lack of evidence to support the use of pre- pro- or synbiotics in patients admitted to adult ICUs, and a large well-designed trial is needed in this area.