Shock. 2021 Aug 11. doi: 10.1097/SHK.0000000000001840. Online ahead of print.
OBJECTIVES: To determine the association of red cell distribution width (RDW) at admission with frequency of acute kidney injury (AKI) and 28-day mortality in acute respiratory distress syndrome (ARDS) patients.
METHODS: 258 ARDS patients were investigated in retrospective and prospective studies. The primary outcome was frequency of AKI. The secondary outcome was 28-day mortality.
RESULTS: The retrospective study included 193 ARDS patients, of which 67 (34.7%) were confirmed AKI and 76 (39.4%) died within 28 days. The RDW level in the AKI group was significantly higher than in the non-AKI group [(15.15 +/- 2.59) % vs. (13.95 +/- 1.89) %]. Increased RDW was a significant predictor of frequency of AKI (OR:1.247, 95% CI: 1.044,1.489). The area under the ROC curve of RDW for predicting AKI was 0.687 (95% CI: 0.610, 0.764) and the cut-off value was 14.45 (sensitivity, 56.7%; specificity, 72.8%). In addition, the proportion of patients with RDW >= 14.45% in the non-survival group was notably higher compared with the survival group (48.7% vs.29.1%). Furthermore, cox regression analysis revealed that RDW >= 14.45% was associated with 28-day mortality (HR:1.817, 95% CI: 1.046, 3.158), while Kaplan-Meier analysis showed patients with RDW >= 14.45% had a significantly lower survival rate than those with RDW < 14.45%. The prospective study, on the other hand, included 65 ARDS patients, with frequency of AKI and 28-day mortality in the RDW >= 14.45% group significantly higher than in RDW < 14.45%.
CONCLUSION: RDW was a significant, independent predictor for frequency of AKI and 28-day mortality in ARDS patients.