Nucleated red blood cell and its specific fluctuations are risk factors of 28-day and 90-day all-cause mortality in ICU patients: an observational cohort study

Abstract

Background Little was known about the first occurrence time of Nucleated red blood cell (NRBC)and the persistent duration of the positive results in ICU patients, nor the dynamic changes of NRBC count and quantified predictive value of NRBC for mortality in ICU patients. We hypothesized that the persistent presence of NRBC in ICU patients would be associated with all-cause mortality and death patients would have specific NRBC fluctuations compared to survival ones.Methods A total of 224 newly admitted ICU patients in our hospital were collected and were followed up to 90 days after admission to ICU. Biological information, clinical characteristics and laboratory indicators and dynamic changes of NRBC count was compared between survival group and death group. Factors plausibly interact with both NRBC and outcome were included in logistic regression analysis to explore the risk factors of 28-day and 90-day mortality,ROC curve were drawn to determine the predictive value of NRBC for 28-day and 90-day all-cause mortality for ICU patients.Results NRBC was positively correlated with NRBC-positive duration days, APACHE II score, SOFA score, CCI, CRP, PCT and RDW. The 28-day mortality and 90-day were 15.0%,31.3%, 41.2%, 56.7% and 32.7%,52.9%, 59.4%, 80.0% in patients with 0/μL, 1–100/μL, 101–200/μL and more than 200/μL NRBC,respectively.NRBC in the death group had a rapid upward trend before death, while those in the survival group were stable at low levels.NRBC was a robust predictor of 28-day and 90-day all-cause mortality following multivariable adjustment. The adjusted odds of 28-day and 90-day all-cause mortality in patients with more than 200/μL NRBC were 5.087(95% CI, 1.960-13.202) and 4.922(95% CI, 1.369-17.703), relative to patients without NRBC. Area under the curve(AUC) of predicting 28-day all-cause mortality and 90-day all-cause mortality by NRBC were 0.685 and 0.670, and NRBC had high predictive values for sepsis patients and non-respiratory failure patients.Conclusion In ICU patients especially sepsis patients and non-respiratory failure patients, the presence of NRBC is a robust predictor of 28-day all-cause mortality and 90-day all-cause mortality. Specific NRBC fluctuations were found in death patients compared to survival ones.