The relationship between high-dose corticosteroid treatment and mortality in acute respiratory distress syndrome: a retrospective and observational study using a nationwide administrative database in Japan

BACKGROUND In the 1980s, randomized-controlled trials showed that high-dose corticosteroid treatment did not improve the mortality of acute respiratory distress syndrome (ARDS). However, while the diagnostic criteria for ARDS have since changed, and supportive therapies have been improved, no randomized-controlled trials have revisited this issue since 1987; thus, the effect of high-dose corticosteroid treatment may be different in this era. We evaluated the effect of high-dose corticosteroid treatment in patients with ARDS using a nationwide administrative database in Japan in a retrospective and observational study. METHODS This study was performed with a large population using the 2012 Japanese nationwide administrative database (diagnostic procedure combination). We evaluated the mortality of ARDS patients receiving or not receiving high-dose corticosteroid treatment within 7 days of hospital admission. We employed propensity score weighting with a Cox proportional hazards model in order to minimize the bias associated with the retrospective collection of data on baseline characteristics and compared the mortality between the high-dose and non-high-dose corticosteroid groups. RESULTS Data from 2707 patients were used; 927 patients were treated with high-dose corticosteroid and 1780 patients were treated without high-dose corticosteroid, within 7 days of admission. After adjusting for confounds, mortality rates within 3 months were significantly higher in the high-dose corticosteroid group compared to the non-high-dose corticosteroid group (weighted hazard ratio: 1.59; 95% CI: 1.37-1.84; P <  0.001). CONCLUSIONS Our results suggest that high-dose corticosteroid treatment does not improve the prognosis of patients with ARDS, even in this era. However, this study has limitations owing to its retrospective and observational design.