title: Micronutrient supplementation for critically ill adults: a systematic review and meta-analysis.
abstract: OBJECTIVE
  This systematic review assessed the effects of micronutrient supplementation on adults recovering from critical illness. Primary outcomes included clinical endpoints (mortality, infectious complications, length of intensive care unit and of hospital stay). Secondary outcomes included descriptions of practice issues, micronutrient status, morbidity, course of the acute-phase response, and oxidative stress.
  
  
  METHODS
  Electronic bibliographic databases, bibliographies of retrieved articles, and personal files were searched and reviewed. Randomized controlled trials (RCTs) of micronutrient supplementation in adult critically ill patients administered enterally and/or parenterally in addition to their routine care were included. Two authors independently extracted data and assessed trial quality. The random-effects model was used to estimate overall relative risk (RR)/mean difference and effect size. P<0.05 was considered statistically significant.
  
  
  RESULTS
  Fifteen (n=1714) and 18 (n=1849) RCTs were included for the primary and secondary objectives, respectively. Fourteen trials (n=1468) showed a statistically significant decrease in overall mortality (RR 0.78, 95% confidence interval 0.67-0.90, I2=0%, P=0.0009). Six RCTs (n=1194) indicated a statistically significant decrease in 28-d mortality (RR 0.75, 95% confidence interval 0.63-0.88, I2=0%, P=0.0006). Micronutrient supplementation was not associated with a decrease in infectious complications, length of intensive care unit, or length of hospital stay. In subgroup analyses, a sensitivity analysis of combined micronutrients indicated a significant decrease in mortality (RR 0.69, 95% confidence interval 0.54-0.90, I2=2%, P=0.006). The secondary outcomes confirmed that timing, duration, and dosing appear to be key factors to ensure optimal clinical benefit.
  
  
  CONCLUSIONS
  This review does suggest a potential benefit of micronutrient supplementation in critically ill adults by possibly being associated with a decrease in mortality.
authors.affiliation: Division of Human Nutrition, Stellenbosch University and Tygerberg Academic Hospital, South Africa. jconrad@sun.ac.za
authors.forename: Janicke
authors.initials: J
authors.lastname: Visser
authors.forename: Demetre
authors.initials: D
authors.lastname: Labadarios
authors.forename: Renée
authors.initials: R
authors.lastname: Blaauw
mesh_terms: D016638:Critical Illness / Q000628:therapy*; D019587:Dietary Supplements; D017052:Hospital Mortality; D006801:Humans; D018977:Micronutrients / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D018977:Micronutrients