Selenium supplementation for critically ill adults
Abstract
Background
Selenium is a trace mineral essential to health and has an important role in immunity, defence against tissue damage and thyroid function. Improving selenium status could help protect against overwhelming tissue damage and infection in critically ill adults.
Objectives
This review assessed the effects of selenium supplementation, including the selenium‐containing compound ebselen, on adults recovering from critical illness.
Search methods
We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2007, Issue 3), MEDLINE, EMBASE, CAB NAR, BIOSIS, CINAHL, Current Controlled Trials and reference lists. We contacted investigators and handsearched four journals. The date of the most recent search was August 2007.
Selection criteria
Randomized trials of selenium or ebselen supplementation by any route in adults with critical illness (including patients with burns, head injury, brain haemorrhage, cerebrovascular accident) and after surgery.
Data collection and analysis
Two authors independently extracted data and assessed trial quality. We sought additional information as required from trialists. We undertook pooling of data for outcomes and selected exploratory analyses were undertaken.
Main results
Ten randomized trials involving 1172 participants were included. The quality of trials, as reported, was poor, particularly for allocation concealment. The availability of outcome data was limited and trials involving selenium supplementation were mostly small. Thus the results must be interpreted with caution.
Seven trials of intravenous sodium selenite showed no statistically significant difference in mortality (relative risk (RR) 0.75, 95% confidence interval (CI) 0.53 to 1.06). In general intensive care patients the RR for selenium supplementation was 0.75 (95% CI 0.59 to 0.96). Three trials of ebselen showed no statistically significant difference in mortality (RR 0.83, 95% CI 0.51 to 1.35).
Three trials of intravenous sodium selenite found no statistically significant difference between groups for participants developing infection (RR 1.22, 95% CI 0.67 to 2.23). Three trials of ebselen provided data for participants developing infections (pyrexia, respiratory infections or meningitis), which were not statistically significant (RR 0.60, 95% CI 0.36 to 1.02).
No clear evidence emerged for the benefits of selenium or ebselen supplementation for the outcomes of days on a ventilator, length of intensive care unit stay, length of hospital stay or quality of life.
Authors' conclusions
There is limited evidence to recommend supplementation of critically ill patients with selenium or ebselen. Trials are required which overcome the defects of the reviewed studies, particularly inadequate size and methodology.
PICOs
Plain language summary
Selenium supplements for adults who are critically ill
Selenium is a mineral that is essential to health. It has an important role in defence against tissue damage and disease and improving selenium status could help protect adults with overwhelming illness. This review assessed the effects of selenium supplementation on adults recovering from critical illness.
Ten trials involving 1172 participants were included. The quality of trials, as reported, was poor. Outcome data were limited and these trials involving selenium supplementation were mostly small. Thus the results must be interpreted with caution.
Seven trials of intravenous sodium selenite showed no effect on mortality. Three trials of the selenium‐containing compound ebselen also showed no effect on mortality. No effects on infections or adverse events were found.
No clear evidence emerged for the benefits of selenium or ebselen supplementation for days on a ventilator, length of intensive care unit stay, length of hospital stay or quality of life. There is, therefore, no clear evidence to recommend supplementation of critically ill patients with selenium or ebselen. Trials are required which overcome the defects of the reviewed studies, particularly inadequate size and methodology.
