Effects of omega-3 fatty acid nutrition on mortality in septic patients: a meta-analysis of randomized controlled trials

BACKGROUND: A previous systematic review and meta-analysis reported that omega-3 fatty acids nutrition may reduce mortality in septic patients. As new randomized controlled trials began to accumulate, we conducted an update. METHODS: A PubMed database was searched through Feb 2016, and randomized controlled trials comparing omega-3 fatty acids with control were selected by two reviewers independently. RESULTS: Eleven trials randomly assigning 808 patients were included in the present study. Using a fixed effects model, we found no significant effect of omega-3 fatty acids on overall mortality (risk ratio 0.84; 95 % confidence interval (CI): 0.67 to 1.05, P = 0.12), or infectious complications (risk ratio 0.95; 95 % CI: 0.72 to 1.25, P = 0.70). However, the duration of mechanical ventilation was markedly reduced by omega-3 fatty acids (weighted mean differences (WMD) = −3.82; 95 % CI: −4.61 to −3.04; P < 0.00001). A significant heterogeneity was found when the duration of hospital (I (2) = 93 %; WMD = −2.82; 95 % CI: −9.88 to 4.23, P = 0.43), or intensive care stay (I (2) = 87 %; WMD = −2.70; 95 % CI: −6.40 to 1.00, P = 0.15) were investigated. CONCLUSIONS: Omega-3 fatty acids confer no mortality benefit but are associated with a reduction in mechanical ventilation duration in septic patients. However, low sample size and heterogeneity of the cohorts included in this analysis limits the generalizability of our findings. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12871-016-0200-7) contains supplementary material, which is available to authorized users.