title: Red cell distribution width and risk for venous thromboembolism: a population-based cohort study.
abstract: BACKGROUND
  Red cell distribution width (RDW) has been associated with venous thromboembolism (VTE), but whether RDW is a predictor of first event of VTE is unknown. We investigated the association between RDW and incidence of first event of VTE in a population-based cohort.
  
  
  METHODS
  RDW was measured in 27 042 subjects (aged 45-73 years, 60.6% women), without previous history of VTE or cancer within 5 years before follow-up, who participated in the Malmö Diet and Cancer study during 1991-1996. Incidence of VTE was identified from the patient register and the cause of death register during a mean follow-up of 13.8 years and studied in relation to RDW.
  
  
  RESULTS
  During follow-up, 991 subjects (57.5% women) were affected by VTE (pulmonary embolism or deep venous thrombosis of the lower limbs). After adjustment for potential confounding factors the hazard ratios (HR) for VTE for the second, third and fourth RDW quartiles 1.15 (95% confidence interval 0.94-1.41), 1.41 (1.14-1.73), 1.74 (1.38-2.21), respectively, were compared with the bottom quartile of RDW. In the multivariate model subjects with the top 5% of RDW values compared with the bottom quartile had an even higher risk (HR=2.51, 1.78-2.54). In receiver operating characteristic (ROC) analysis, the male specific area under the ROC curve (AUC) for RDW was 0.57 (95% CI 0.54-0.59). The female specific AUC was 0.56 (95% CI 0.53-0.58).
  
  
  CONCLUSIONS
  RDW was found to be associated with long-term incidence of first event of VTE among middle-aged subjects.
authors.affiliation: Center for Primary Care Research, Lund University/Region Skåne, Malmö, Sweden. Electronic address: bengt.zoller@med.lu.se.
authors.forename: Bengt
authors.initials: B
authors.lastname: Zöller
authors.affiliation: Department of Clinical Sciences, Lund University, Clinical Research Center (CRC), Entrance 72, house 60, level 13, Skåne University Hospital, SE 205 02 Malmö, Sweden.
authors.forename: Olle
authors.initials: O
authors.lastname: Melander
authors.affiliation: Department of Clinical Sciences, Lund University, Clinical Research Center (CRC), Entrance 72, house 60, level 13, Skåne University Hospital, SE 205 02 Malmö, Sweden; Department of Coagulation Disorders, Skåne University Hospital, Malmö, Sweden.
authors.forename: Peter
authors.initials: P
authors.lastname: Svensson
authors.affiliation: Department of Clinical Sciences, Lund University, Clinical Research Center (CRC), Entrance 72, house 60, level 13, Skåne University Hospital, SE 205 02 Malmö, Sweden.
authors.forename: Gunnar
authors.initials: G
authors.lastname: Engström
mesh_terms: D000368:Aged; D015331:Cohort Studies; D004909:Erythrocyte Indices / Q000502:physiology*; D004912:Erythrocytes / Q000473:pathology*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011655:Pulmonary Embolism / Q000097:blood / Q000473:pathology; D012307:Risk Factors; D054556:Venous Thromboembolism / Q000097:blood* / Q000473:pathology
keywords: epidemiology; predictors; pulmonary embolism; venous thromboembolism; venous thrombosis