title: Red blood cell distribution width predicts responsiveness of acute pulmonary vasodilator testing in patients with idiopathic pulmonary arterial hypertension.
abstract: BACKGROUND
  Red blood cell distribution width (RDW) has been shown to predict clinical outcomes in cardiopulmonary vascular diseases. We investigated whether RDW is useful to predict responsiveness of acute pulmonary vasodilator testing in patients with idiopathic pulmonary arterial hypertension (IPAH).
  
  
  METHODS
  RDW was determined in 167 IPAH patients who underwent acute pulmonary vasodilator testing. All subjects were followed up for 20 ± 10 months.
  
  
  RESULTS
  Nineteen out of 167 patients (11.4%) were acute pulmonary vasodilator testing responders. Patients with lower RDW levels ≤ 13.65% (sensitivity 89.5%, specificity 52.7%; AUC: 0.747, 95% CI: 0.632 to 0.861) were more likely to have a positive response. Multivariate logistic regression analysis showed that RDW ≤ 13.65% independently predicted responsiveness of vasodilator testing in patients with IPAH (OR 18.453, 95% CI 2.279-149.391, p = 0.006). RDW correlated with disease severity evaluated by clinical parameters. Patients with increased RDW (> 13.65%) had significantly increased risk of all-cause death (Log-rank p = 0.007).
  
  
  CONCLUSIONS
  RDW independently predicts responsiveness of acute pulmonary vasodilator testing in patients with IPAH. RDW is associated with disease severity and all-cause death.
authors.affiliation: State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, China; Center for Pulmonary Vascular Diseases, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, China.
authors.forename: Qunying
authors.initials: Q
authors.lastname: Xi
authors.affiliation: Center for Pulmonary Vascular Diseases, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, China. Electronic address: fuwaipumc@163.com.
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Center for Pulmonary Vascular Diseases, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, China.
authors.forename: Zhihui
authors.initials: Z
authors.lastname: Zhao
authors.affiliation: Center for Pulmonary Vascular Diseases, State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Luo
mesh_terms: D000328:Adult; D054316:Biomarkers, Pharmacological / Q000032:analysis; D002121:Calcium Channel Blockers / Q000627:therapeutic use; D004077:Digoxin / Q000627:therapeutic use; D004232:Diuretics / Q000627:therapeutic use; D004909:Erythrocyte Indices; D004912:Erythrocytes / Q000473:pathology*; D065627:Familial Primary Pulmonary Hypertension / Q000175:diagnosis* / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016015:Logistic Models; D008297:Male; D011379:Prognosis; D012372:ROC Curve; D012720:Severity of Illness Index; D016019:Survival Analysis; D014664:Vasodilation / Q000187:drug effects; D014665:Vasodilator Agents / Q000627:therapeutic use*
chemical_list: D054316:Biomarkers, Pharmacological; D002121:Calcium Channel Blockers; D004232:Diuretics; D014665:Vasodilator Agents; D004077:Digoxin
keywords: Acute pulmonary vasodilator testing; Pulmonary hypertension; Red blood cell distribution width