Open Access Highly Accessed Research article

Is elevated Red cell distribution width a prognostic predictor in adult patients with community acquired Pneumonia?

Eyal Braun13*, Jad Kheir3, Tanya Mashiach23, Mohammad Naffaa13 and Zaher S Azzam134

Author Affiliations

1 Departments of Medicine H and B, Rambam Health Care Campus, P.O. Box 9602, 31096 Haifa, Israel

2 Biostatistics Unit, Rambam Health Care Campus, Haifa, Israel

3 Rappaport Family Faculty of Medicine, Haifa, Israel

4 Research Institute. Technion, Israel Institute of Technology, Haifa, Israel

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BMC Infectious Diseases 2014, 14:129  doi:10.1186/1471-2334-14-129

Published: 5 March 2014

Abstract

Background

Community acquired pneumonia (CAP) is a major cause of morbidity and mortality. We recently demonstrated that among young patients (<60 years old) with CAP, elevated red blood cell distribution width (RDW) level on admission was associated with significant higher rates of mortality and severe morbidity. We aimed to investigate the prognostic predictive value of RDW among CAP patients in general population of internal wards.

Methods

The cohort included patients of 18 years old or older who were diagnosed with CAP (defined as pneumonia identified 48 hours or less from hospitalization) between January 1, 2005 and December 31, 2010. Patients were retrospectively analyzed for risk factors for a primary endpoint of 90-day mortality. Secondary endpoint was defined as complicated hospitalization (defined as at least one of the following: In- hospital mortality, length of stay of at least 10 days or ICU admission). Binary logistic regression analysis was used for the calculation of the odds ratios (OR) and p values in univariate and multivariate analysis to identify association between patient characteristic, 90-day mortality and complicated hospitalization.

Results

The cohort included 3815 patients. In univariate analysis, patients with co-morbid conditions tended to have a complicated course of CAP. In multivariate regression analysis, variables associated with an increased risk of 90-day mortality included age > 70 years, high Charlson comorbidity index (>2), Hb < 10 mg/dl, Na <130 meq/l, blood urea nitrogen (BUN) >30 mg/dl, systolic blood pressure < 90 mmHg and elevated RDW >15%. Variables associated with complicated hospitalization included high Charlson comorbidity index, BUN > 30 mg/dl, hemoglobin < 10 g/dl, heart rate >124 bpm, systolic blood pressure < 90 mmHg and elevated RDW. Mortality rate and complicated hospitalization were significantly higher among patients with increased RDW regardless of the white blood cell count or hemoglobin levels.

Conclusions

Elevated RDW levels on admission are associated with significant higher rates of mortality and severe morbidity in adult patients with CAP. RDW as a prognostic marker was unrelated with hemoglobin levels, WBC count, age or Charlson score.

Keywords:
Community acquired pneumonia; Red blood cell distribution width; Mortality; Complicated hospitalization