The effects of steroids during sepsis depend on dose and severity of illness: an updated meta-analysis

Abstract

A previous meta-analysis determined that the effects of steroids during sepsis were dose-dependent; since then, additional trials have been published. The current analysis updates our previous analysis examining the effects of steroids during sepsis. A literature search from 2004 to 2008 identified seven randomized controlled trials in adult patients; these were added to 14 previously identified trials. The effects of steroids on mortality were highly variable among the 21 trials (p <0.001, I(2) = 60%). In trials published before 1989, which involved short courses of high-dose steroids, steroids increased mortality (n = 8, I(2) = 14%, OR of death 1.39 (95% CI 1.04-1.86), p 0.03). In trials published after 1997, which involved longer courses of lower-dose steroids, steroids consistently improved shock reversal (n = 7, I(2) = 0%, OR of shock reversal 1.66 [95% CI 1.25-2.20), p <0.001), but demonstrated a more heterogeneous beneficial effect on mortality (n = 12, I(2) = 25%, OR of death 0.64 (95% CI 0.45-0.93), p 0.02). An inverse linear relationship between severity of illness and the effects of steroids on mortality was identified across all trials (p 0.03) and within the subgroup of trials published after 1997 (p 0.03); steroids were harmful in less severely ill patient populations and beneficial in more severely ill patient populations. There was no effect of response to adrenocorticotrophic hormone (ACTH) stimulation testing concerning the effects of steroids and no increase in steroid-associated adverse events. Low-dose steroids appear to improve mortality rates in patients with septic shock who are at high risk of death; however, additional trials in this subpopulation are necessary to definitively determine the role of low-dose steroids during sepsis.

Figures

FIG. 1

Study selection flow diagram.

FIG. 2

Effects of steroids on mortality in randomized controlled sepsis trials. The OR of death and 95% CI with steroid therapy is shown. Analysis of all 21 trials demonstrated variability in the effects of steroids on mortality (I2 = 60%, p <0.001). As previously, studies were partitioned into those published before 1989 and after 1997 to decrease heterogeneity. In the 12 trials published after 1997, there remained a moderate amount of heterogeneity in the effects of steroids on mortality (I2 = 25%, p 0.20), with an overall decrease in the OR of death with steroid therapy (p 0.02). Significant heterogeneity remained in the treatment effects of steroids in the nine trials published before 1989 (I2 = 73%, p <0.001). Removal of a single trial that was a significant outlier [33] decreased the heterogeneity in these trials (I2 = 14%, p 0.33). In the remaining eight trials published before 1989, steroids significantly increased the OR of mortality (p 0.03).

FIG. 3

Influence of steroid dose and severity of illness on the effects of steroids on mortality. (a) There is a significant linear relationship between the dose of steroids administered in the first 24 h after study enrolment and the OR of death across the steroid sepsis trials (p 0.03); steroids decreased mortality at lower doses, and increased mortality as steroid dose increased. (b) A significant inverse linear relationship between the control odds of death (a measure of severity of illness) and the OR of death also exists across the steroid sepsis trials (p 0.03); steroids increase mortality in patient populations with a low control odds of death (less severely ill), and decrease mortality in patient populations with a high control odds of death (more severely ill). As in our previous analysis, a single overly influential trial with methodological differences was identified and removed from these meta-regression analyses [25]. (c) In the subgroup of trials published after 1997 that administered only lower-dose steroids (range in hydrocortisone equivalents: 30–420 mg over first 24 h after enrolment), a similar significant inverse linear relationship between the control odds of death and the OR of death exists (p 0.03), suggesting that low-dose steroids increase mortality in less severely ill patient populations and decrease mortality in more severely ill patient populations.

FIG. 4

Effects of low-dose steroids on mortality based on response to adrenocorticotropic hormone (ACTH) stimulation testing and the effects of steroids on shock reversal. (a) The OR of death and 95% CI with steroid therapy based on patient response to a 250-μg ACTH stimulation test are shown for the five trials published after 1997 that reported mortality results using these subgroups [8,20,22,26,36]. The treatment effects of steroids on mortality based on response to ACTH stimulation testing were similar (p 0.86) and consistent within both subgroups and combined groups (non-responder, I2 = 0%; responder, I2 = 14%; combined, I2 = 0%). Low-dose steroids demonstrated similar non-significant decreases in mortality in both non-responders (OR of death 0.84, 95% CI 0.59–1.12, p 0.33) and responders (OR of death 0.83, 95% CI 0.50– 1.39, p 0.49) to ACTH stimulation testing. (b) The OR of 28-day shock reversal and 95% CI with steroid therapy is displayed for the seven trials published after 1997 reporting this outcome. Low-dose steroids consistently improved 28-day shock reversal (p 0.70, I2 = 0%), with a significant increase in shock reversal in patients treated with steroids as compared with controls (OR of shock reversal 1.66, 95% CI 1.25–2.20, p <0.001).

FIG. 5

Publication bias and jackknife sensitivity analysis in the steroid trials published after 1997. (a) A funnel plot of precision versus the log odds ratio of death with steroid therapy for the trials published after 1997 is presented; visual inspection of the plot suggests potential publication bias. There are a disproportionately high number of published small trials demonstrating beneficial treatment effects of steroids (demonstrated by the solid circles with negative log odds ratios of death on the lower left of the vertical line in the middle of the graph) than published small trials demonstrating harmful effects of steroids (reflected by paucity of solid circles with positive log odds ratios of death on the lower right of the vertical line in the middle of the graph). (b) A jackknife sensitivity analysis examining the heterogeneity of the treatment effects of steroids on mortality in the group of trials published after 1997 is displayed. The individual trials are ordered on the X-axis by the change in I2 in when each trial is removed one at time. This analysis identified that eight studies increased heterogeneity (I2 increased; represented by the corresponding circle with the study name to the right of the vertical line at zero) and four studies decreased heterogeneity (I2 decreased; represented by the corresponding circle with the study name to the left of the vertical line at zero) when the individual study was removed. The two studies with the largest effects on the heterogeneity among these 12 trials are on the far left of the figure. When the CORTICUS trial [22] is removed, the I2 goes from 25% to 0%; when the trial Confalanieri et al. [18] is removed, I2 goes from 25% to 11%. Of note, these trials represent the largest randomized controlled trial and the trial with the largest beneficial treatment effect of steroids respectively. Circle size is proportional to overall study size.