Seven studies (n=11,425) were included in the review. Sample sizes in the studies ranged between 504 to 6,022 patients. All studies attained a Jadad score of 3.
Significantly higher levels of hypoglycaemia were observed in the group that received intensive insulin therapy (OR 7.7, 95% CI 6.0 to 9.9).
There were no statistically significant differences reported between the group that received insulin-intensive therapy and the group that received less strict glucose control for 28-day mortality, incidence of bloodstream infections and need for renal replacement therapy.
Subgroup analyses found a trend towards beneficial treatment effects of intensive insulin therapy on 28-day mortality when 87% of calories were provided intravenously (OR 1.203, 95% CI 0.982 to 1.474). Significant negative treatment effects were found on 28-day mortality when low percentages of calorie intake were provided intravenously (OR 0.899, 95% CI 0.811 to 0.997).
The reviewers stated that there was no evidence of publication bias on visual appraisal of the funnel plot.