Corticosteroid therapy for acute lung injury, acute respiratory distress syndrome, and severe pneumonia: a meta-analysis of randomized controlled trials

Background: Randomized trials investigating the effect of corticosteroids in the treatment of acute lung injury, acute respiratory distress syndrome, and severe pneumonia have had mixed results. We sought to determine whether systemic corticosteroids reduce hospital mortality from these illnesses.

Methods: We conducted a systematic review of published and unpublished randomized trials. We searched MEDLINE, EMBASE, CENTRAL, and CINAHL and reviewed proceedings from relevant society meetings. Two reviewers screened the literature and extracted data independently. For each outcome, we used Grading of Recommendations Assessments, Development and Evaluation (GRADE) criteria to evaluate the quality of the underlying evidence.

Results: We included 12 trials enrolling 966 patients. Pooling across all trials, corticosteroids did not significantly reduce hospital mortality (relative risk, 0.84; 95% confidence interval, 0.66-1.06). In a subgroup analysis by dose of corticosteroid, trials using the equivalent of 2 mg kg(-1) d(-1) or less of methylprednisolone (9 trials) found lower hospital mortality with corticosteroid therapy (relative risk 0.68; 95% confidence interval, 0.49-0.96). The quality of the evidence underlying the pooled estimate of effect on hospital mortality was low, downgraded for inconsistency and imprecision.

Conclusions: Low-dose corticosteroids administered within 14 days of disease onset may reduce all-cause mortality in patients with acute lung injury, acute respiratory distress syndrome, and severe pneumonia. However, the overall quality of the evidence precludes definitive conclusions regarding the use of corticosteroids in this population.