Probiotics are effective in decreasing the incidence of ventilator-associated pneumonia in adult patients: a meta-analysis of randomized controlled trials

Ventilator-associated pneumonia (VAP) is one of the most common nosocomial infections found in intensive care units (ICU). Previous studies have found probiotics to be beneficial for a range of diseases. This present study investigated whether they could prevent VAP in critically ill patients. PubMed and Web of Science were searched to identify appropriate randomized controlled trials. The study included a total of 10 studies with 1,403 patients. Heterogeneity was analyzed by Cochran's Q statistic and pooled Mantel-Haenszel relative risks were calculated using either a fixed-effects or random-effects model. Results showed a significant difference between patients given probiotics (25.71%) and the control group (32.70%) in terms of incidence of VAP (odds ratio (OR) 0.69, 95% confidence interval 0.54 to 0.88, P = 0.003). There was also a significant difference (P = 0.0001) between the group given probiotics and the control group in terms of antibiotic usage for VAP (mean deviation -3.00, 95% CI -5.96 to 0.04): antibiotics were given over fewer days in the probiotics group. However, there were no significant differences in terms of incidence of diarrhea (OR = 0.72, 95% CI = 0.49 to 1.09, P = 0.12), ICU mortality (OR 0.95, 95% CI 0.67 to 1.33, P = 0.76), hospital mortality (OR = 0.86, 95% CI = 0.62 to 1.18, P = 0.35), length of ICU stay (MD = -1.74, 95% CI = -6.74 to 3.27, P = 0.50), or duration of mechanical ventilation (MD = -6.21, 95% CI = -18.83 to 6.41, P = 0.34). In this meta-analysis, reduced incidence of VAP in ICU patients given probiotics was found. It seems likely that probiotics provide clinical benefits.