Association between red blood cell distribution width and mortality in diabetic ketoacidosis

Background No epidemiological studies have assessed the impact of red blood cell distribution width (RDW) on the prognosis of diabetic ketoacidosis (DKA) patients in the intensive care unit (ICU). Thus, we investigated whether RDW was associated with mortality in DKA patients. Material and method We analyzed data from MIMIC-III. RDW was measured at ICU admission. The relationship between RDW and mortality of DKA was determined using a multivariate Cox regression analysis. The primary outcome of the study was 365-day mortality from the date of ICU admission. We also conducted a subgroup analysis to further confirm the consistency of associations. Results In total, 495 critically ill DKA patients were eligible for analysis. In the univariable Cox regression model for 365-day all-cause mortality, RDW was a predictor of all-cause mortality in DKA patients (hazard ratio [HR]: 1.30, 95% confidence interval [CI]: 1.19–1.43). After adjusting for confounders, RDW was still a particularly strong predictor (HR: 1.23, 95% CI: 1.05–1.45). The same relationship was also observed for 90-day all-cause mortality (HR: 1.29, 95% CI: 1.02–1.65). Conclusions High RDW was associated with risk of all-cause mortality in DKA patients in the ICU. RDW was an independent prognostic factor for these patients.