Abstract 16321: Increases in Red Cell Distribution Width as a Biomarker for Deep Vein Thrombosis
Emerging evidence suggests a role for red cell distribution width (RDW) as a marker for poor outcome in many diseases; the higher RDW, the worse the prognosis. Although the mechanisms responsible for this association are, as yet, speculative, increased RDW is thought to reflect underlying inflammation. As inflammation is a purported factor in the etiology of thrombosis, we hypothesized that patients with deep vein thrombosis (DVT) would exhibit increased RDW.
Methods: For all suspected DVTs (identified by ICD-9 codes) evaluated in the Emergency Department between 2004 and 2008, we recorded DVT site (proximal/distal), RDW (%), hemoglobin (g/dL), demographics including self-reported ethnicity (African [AA] or European ancestry [EA]), and length of hospital stay (LOS). Medians [interquartile range] were calculated and compared in 2 groups: (1) DVT (confirmed by sonography; n = 1,217) and (2) control (no DVT; n = 918), with ethnicity included as a covariate.
Results: RDW differed between groups (P<0.0001; ANOVA) and was higher in patients of African vs. European ancestry (P<0.01). For AA patients, RDW increased with DVT vs. no DVT (P<0.01). Subgroup analysis revealed greater RDW in proximal vs. distal DVT (14.8 vs. 14.4%; P<0.007). Notably, although there was an inverse correlation between hemoglobin and RDW (P<0.0001: an association between RDW and anemia), regression analysis revealed RDW increases with DVT were independent of anemia. Also, when RDW was divided into quartiles, patients in the 4th quartile (≥16.2%) had increased LOS vs. 1st quartile (≤ 13.6%); 4 vs. 3 days (P<0.01). For EA patients, RDW increase with DVT was attenuated; but, RDW was again greater in proximal vs. distal DVT (14.3 vs. 13.4%; P<0.0001).
Conclusion: DVT was associated with RDW increases in AA patients. For both ethnic cohorts, the largest RDW increases occurred for proximal DVTs. Our data provide evidence that RDW could serve as a biomarker for DVT and predictor of increased LOS for AA patients.
- © 2011 by American Heart Association, Inc.