title: Usefulness of red cell distribution width as a prognostic marker in pulmonary hypertension.
abstract: Red blood cell distribution width (RDW), a widely available biomarker, independently predicts adverse outcomes in left-sided heart failure. The relation between RDW and death in pulmonary hypertension (PH) is unknown. In a prospective study of 162 consecutive patients with PH, RDW was recorded during initial diagnostic right-sided cardiac catheterization, and patients were followed for 2.1 +/- 0.8 years to determine vital status. Demographic, clinical, laboratory, and hemodynamic variables were compared by tertile of RDW. Cox proportional-hazards models were used to determine whether RDW was independently associated with death, and the prognostic utility of RDW was compared to that of other laboratory predictors, including N-terminal-pro-B-type natriuretic peptide (NT-pro-BNP). Of the 162 study patients, 78% were women, and 62% had pulmonary arterial hypertension. The mean age was 53 +/- 15 years, and most patients had severe PH (mean pulmonary artery pressure 48 +/- 13 mm Hg). The highest tertile of RDW predicted death (univariate hazard ratio 4.86, 95% confidence interval 1.37 to 17.29, p = 0.015; multivariate hazard ratio 2.4, 95% confidence interval 1.02 to 5.84, p = 0.045, after adjusting for age, gender, diabetes mellitus, connective tissue disease, diuretic use, phosphodiesterase inhibitor use, hemoglobin, mean corpuscular volume, and blood urea nitrogen [BUN]). Of the laboratory data, only RDW, BUN, and NT-pro-BNP were associated with death on univariate analysis. When RDW, BUN, and NT-pro-BNP were entered into a multivariate model, only RDW was still associated with death (p = 0.037 for RDW, p = 0.18 for BUN, and p = 0.39 for NT-pro-BNP). Adding NT-pro-BNP to RDW did not improve the prediction of mortality. In conclusion, RDW is independently associated with death in patients with PH and performs better as a prognostic indicator than NT-pro-BNP.
authors.affiliation: Section of Cardiology, Department of Medicine, University of Chicago, Chicago, Illinois, USA.
authors.forename: Chetan V
authors.initials: CV
authors.lastname: Hampole
authors.forename: Amit K
authors.initials: AK
authors.lastname: Mehrotra
authors.forename: Thenappan
authors.initials: T
authors.lastname: Thenappan
authors.forename: Mardi
authors.initials: M
authors.lastname: Gomberg-Maitland
authors.forename: Sanjiv J
authors.initials: SJ
authors.lastname: Shah
mesh_terms: D000328:Adult; D000368:Aged; D004909:Erythrocyte Indices; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000097:blood* / Q000401:mortality*; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood; D010446:Peptide Fragments / Q000097:blood; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies
chemical_list: D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain