Original ContributionRed cell distribution width is a prognostic factor in severe sepsis and septic shock
Introduction
Severe sepsis and septic shock are increasing in incidence, and the mortality rate is still elevated [1], [2]. The prediction of outcome for patients with sepsis may facilitate more aggressive interventions, and many prognostic factors such as age, sex, comorbidities, biomarkers, and severity of illness have been reported to be associated with outcome [3], [4], [5].
Red cell distribution width (RDW) is a measure of the variability in the size of circulating red blood cells and is a part of the complete blood count (CBC) panel. It is mainly used as a tool for the differential diagnosis of anemia and could be elevated in any conditions where reticulocytes are released into circulation.
Besides the evaluation of anemia, recent studies have reported that RDW is also associated with prognosis in patients with congestive heart failure, acute myocardial infarction, pulmonary embolism, pneumonia, critical illness, and cardiac arrest [6], [7], [8], [9], [10], [11]. The mechanism of elevated RDW in these patients is not known, but it has been suggested that inflammatory process is associated with elevated RDW. It has been reported that elevated RDW is associated with inflammatory markers such as interleukin-6 and tumor necrosis factor, and proinflammatory cytokines could suppress the maturation of red blood cells and decrease the half-life of red blood cells, which, in turn, results in an elevated RDW [10], [12], [13].
The inflammatory response is important to the pathophysiology of sepsis, but there are few studies about the RDW and sepsis. In a study of critically ill patients, higher frequency of sepsis was observed in groups with higher RDW, and elevated RDW was associated with bloodstream infection [10]. However, this study included the patients admitted to intensive care unit (ICU) and did not focus on the septic patients.
We hypothesized that RDW, as a marker of inflammation, may be associated with mortality in sepsis. Therefore, we performed this study to evaluate the relationship between RDW at admission and 28-day mortality in patients with severe sepsis and septic shock.
Section snippets
Study population
We performed a retrospective analysis of prospectively collected patients' data with severe sepsis and septic shock at an urban, tertiary care, emergency department with an annual census of approximately 70 000 between January 1, 2009, and December 31, 2011. The institutional review board approved this study.
We retrospectively analyzed the prospective data of adult patients older than 18 years who visited an emergency department and were diagnosed as having severe sepsis and septic shock.
Characteristics of study population
During the study period, a total of 590 patients were initially included. Of them, 24 patients were excluded because of withdrawal aggressive management. Therefore, 566 patients were included into the final analysis, and there was no loss to follow-up at 28 days.
The mean age of the enrolled patients was 70.0 ± 13.4 years, 314 (55.5%) were male, and 164 patients (29.0%) died during the 28-day follow-up period. Nonsurvivors were older and had more male patients (Table 1). The 3 most frequent
Discussion
In the present study, we observed that RDW of nonsurvivors was higher than that of survivors in severe sepsis and septic shock, and there was a graded association between RDW and 28-day mortality. In addition, RDW had a relationship with the severity of the patients and was an independent prognostic factor of 28-day mortality in patients with severe sepsis and septic shock.
The association of RDW with mortality was evaluated in patients with general cardiovascular diseases [17]. Subsequent
Limitations
The major limitation of the present study is a retrospective analysis of data in a single institution, and the results of this study might not be generalizable to other institutions. Second, RDW could be influenced by iron, folate, and vitamin B12, but we did not measure those variables. Third, this is a retrospective analysis, and the transfusion records of the patients before admission are not available. Last, the results of this study show the association of RDW with 28-day mortality but do
Conclusions
Red cell distribution width at admission is associated with 28-day mortality and severity of patients with severe sepsis and septic shock. Therefore, RDW could be used as a prognostic factor in severe sepsis and septic shock.
References (27)
- et al.
Nationwide trends of severe sepsis in the 21st century (2000-2007)
Chest
(2011) - et al.
Identifying potentially ineffective care in the sickest critically ill patients on the third ICU day
Chest
(2004) - et al.
Septic shock
Lancet
(2005) - et al.
Red cell distribution width as a novel prognostic marker in heart failure: data from the CHARM Program and the Duke Databank
J Am Coll Cardiol
(2007) - et al.
Relation between red cell distribution width and clinical outcomes after acute myocardial infarction
Am J Cardiol
(2010) - et al.
Usefulness of admission red cell distribution width as a predictor of early mortality in patients with acute pulmonary embolism
Am J Cardiol
(2012) - et al.
Red blood cell distribution width as an independent predictor of all-cause mortality in out of hospital cardiac arrest
Resuscitation
(2012) - et al.
Definitions for sepsis and organ failure and guidelines for the use of innovative therapies in sepsis. The ACCP/SCCM Consensus Conference Committee. American College of Chest Physicians/Society of Critical Care Medicine
Chest
(1992) - et al.
Heart-type fatty acid–binding protein as a prognostic factor in patients with severe sepsis and septic shock
Am J Emerg Med
(2012) - et al.
Usefulness of a complete blood count-derived risk score to predict incident mortality in patients with suspected cardiovascular disease
Am J Cardiol
(2007)
Red cell distribution width, C-reactive protein, the complete blood count, and mortality in patients with coronary disease and a normal comparison population
Clin Chim Acta
Elevated red blood cell distribution width predicts mortality in persons with known stroke
J Neurol Sci
Red cell distribution width and risk of coronary heart disease events
Am J Cardiol
Cited by (167)
Red blood cell distribution width as prognostic factor in sepsis: A new use for a classical parameter
2022, Journal of Critical CareRed Blood Cell Distribution Width as a Diagnostic Marker of Hepatocellular Carcinoma in Cirrhotic Patients
2024, Open Biomarkers JournalExplainable machine learning using perioperative serial laboratory results to predict postoperative mortality in patients with peritonitis-induced sepsis
2023, Annals of Surgical Treatment and Research