title: Biomarkers for risk stratification in secondary cardiovascular prevention. A role of red blood cell distribution width and calcium score.
abstract: BACKGROUND
  Patients with coronary artery disease (CAD) are considered as high risk in terms of secondary cardiovascular prevention. However, obviously the risk is not homogenous across the whole group. Red blood cell distribution width (RDW) has been recently related to adverse outcomes in patients with atherosclerosis. Calcium score (CaS) may be used for risk stratification in primary prevention. The value of these biomarkers for prediction of cardiovascular outcomes in patients with CAD is unknown.
  
  
  METHODS
  The study group comprised 269 consecutive patients with significant stable CAD. The primary endpoint was a composite of death or nonfatal myocardial infarction.
  
  
  RESULTS
  Median post-discharge follow up was 43.2 months (IQR39.2-48.6). The primary outcome was observed in 27 patients including 13 deaths and 14 nonfatal myocardial infarction. According to ROC analysis the best cut-off value for RDW for prediction of the primary event was 14% [(AUC) = 0.69; 95%CI:0.63-0.75; p = 0.0002] and for CaS was 603 [(AUC) = 0.66; 95%CI:0.60-0.72; p = 0.001]. According to multivariable Cox regression analysis both RDW>14% (HR 2.6; 95%CI:1.1-5.9) and CaS>603 (HR 2.3; 95%CI:1.1-5.1) were independently correlated to the primary outcome. Subsequently, patients were categorized into three risk subgroups: LOW: CaS ≤ 603 and RDW ≤ 14-124(46.1%), MID: either CaS>603 or RDW>14-104(38.7%), and HIGH - CaS>603 and RDW>14-41(15.2%) patients. The respective risk of events according to Kaplan-Meier analysis were 4.03%, 9.62%, and 29.27% (p < 0.0001).
  
  
  CONCLUSIONS
  RDW and calcium score may be predictors of future cardiovascular events in patients with significant CAD. They may be useful tools for risk stratification and may indicate patients suitable for more aggressive secondary prevention measures.
authors.affiliation: Department of Coronary and Structural Heart Diseases, Institute of Cardiology, 42 Alpejska St, 04-628 Warsaw, Poland. Electronic address: annaoleksiak.pl@gmail.com.
authors.forename: Anna
authors.initials: A
authors.lastname: Oleksiak
authors.affiliation: Department of Coronary and Structural Heart Diseases, Institute of Cardiology, 42 Alpejska St, 04-628 Warsaw, Poland. Electronic address: mkruk@ikard.pl.
authors.forename: Mariusz
authors.initials: M
authors.lastname: Kruk
authors.affiliation: Department of Coronary and Structural Heart Diseases, Institute of Cardiology, 42 Alpejska St, 04-628 Warsaw, Poland.
authors.forename: Ewelina
authors.initials: E
authors.lastname: Lenarczyk
authors.affiliation: Department of Coronary and Structural Heart Diseases, Institute of Cardiology, 42 Alpejska St, 04-628 Warsaw, Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Pawelec
authors.affiliation: Department of Coronary and Structural Heart Diseases, Institute of Cardiology, 42 Alpejska St, 04-628 Warsaw, Poland.
authors.forename: Ewa
authors.initials: E
authors.lastname: Rajska
authors.affiliation: Department of Coronary and Structural Heart Diseases, Institute of Cardiology, 42 Alpejska St, 04-628 Warsaw, Poland.
authors.forename: Paulina
authors.initials: P
authors.lastname: Wilkońska
authors.affiliation: Department of Coronary and Structural Heart Diseases, Institute of Cardiology, 42 Alpejska St, 04-628 Warsaw, Poland.
authors.forename: Zofia
authors.initials: Z
authors.lastname: Dzielińska
authors.affiliation: Department of Coronary and Structural Heart Diseases, Institute of Cardiology, 42 Alpejska St, 04-628 Warsaw, Poland.
authors.forename: Marcin
authors.initials: M
authors.lastname: Demkow
authors.affiliation: Department of Invasive Cardiology and Angiology, Institute of Cardiology, 42 Alpejska St, 04-628 Warsaw, Poland.
authors.forename: Adam
authors.initials: A
authors.lastname: Witkowski
authors.affiliation: Department of Invasive Cardiology and Angiology, Institute of Cardiology, 42 Alpejska St, 04-628 Warsaw, Poland.
authors.forename: Jerzy
authors.initials: J
authors.lastname: Pręgowski
authors.affiliation: Department of Coronary and Structural Heart Diseases, Institute of Cardiology, 42 Alpejska St, 04-628 Warsaw, Poland.
authors.forename: Cezary
authors.initials: C
authors.lastname: Kępka
authors.affiliation: Department of Coronary and Structural Heart Diseases, Institute of Cardiology, 42 Alpejska St, 04-628 Warsaw, Poland.
authors.forename: Witold
authors.initials: W
authors.lastname: Rużyłło
mesh_terms: D000368:Aged; D019540:Area Under Curve; D000072226:Computed Tomography Angiography; D017023:Coronary Angiography / Q000379:methods*; D003324:Coronary Artery Disease / Q000097:blood / Q000000981:diagnostic imaging / Q000401:mortality / Q000628:therapy*; D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D004909:Erythrocyte Indices; D004912:Erythrocytes; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000209:etiology / Q000517:prevention & control; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D012372:ROC Curve; D012042:Registries; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D055502:Secondary Prevention / Q000379:methods*; D012720:Severity of Illness Index; D013997:Time Factors; D016896:Treatment Outcome; D061205:Vascular Calcification / Q000097:blood / Q000000981:diagnostic imaging / Q000401:mortality / Q000628:therapy*
keywords: Calcium score; Coronary artery disease; RDW; Secondary prevention