title: The impact of anemia on long-term clinical outcome in patients undergoing revascularization with the unrestricted use of drug-eluting stents.
abstract: BACKGROUND
  Anemia is frequent among patients with cardiovascular disease and adversely affects prognosis. The objective of this analysis was to assess the impact of anemia on long-term clinical outcomes among patients undergoing percutaneous coronary intervention (PCI) with the unrestricted use of drug-eluting stents (DES).
  
  
  RESULTS
  Between April 2002 to March 2009, 6528 consecutive patients underwent PCI with the unrestricted use of DES. Among patients with anemia according to the criteria by the World Health Organization (WHO) (hemoglobin <130 g/L for men and <120 g/L for women, respectively) patients below the 25(th) percentile separately for men and women were defined to have severe anemia. We compared clinical outcomes among patients with severe anemia and no/mild anemia during long-term follow-up through 4 years. Whereas 21.6% of patients were found to have anemia according to the WHO definition, 347 patients (5.5%) had severe anemia (mean hemoglobin, 98±11 g/L). Severe anemia was more prevalent among the elderly (P<0.001), diabetics (P<0.001), and patients with chronic kidney disease (P<0.001). In adjusted analyses, severe anemia was associated with an increased risk of death (hazard ratio, 1.86; 95% confidence interval, 1.37-2.52; P<0.0001), cardiac death (hazard ratio, 2.32; 95% confidence interval, 1.57-3.43; P<0.0001), and myocardial infarction (hazard ratio, 2.02; 95% confidence interval, 1.36-3.01; P=0.00054) as compared with no/mild anemia without significant interaction across sexes (P=0.86) and acute coronary syndromes (P=0.61) and a trend toward a particularly high risk of mortality among anemic patients <65 years of age (P=0.07). Severe anemia resulted in a greater risk of overall definite stent thrombosis (hazard ratio, 2.59; 95% confidence interval, 1.48-4.54; P=0.00089).
  
  
  CONCLUSIONS
  Severe anemia is common among patients undergoing PCI with the unrestricted use of DES and adversely affects long-term prognosis, including survival.
authors.affiliation: Department of Cardiology, Swiss Cardiovascular Center, Bern University Hospital, Bern, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Pilgrim
authors.forename: Florian
authors.initials: F
authors.lastname: Vetterli
authors.forename: Bindu
authors.initials: B
authors.lastname: Kalesan
authors.forename: Giulio G
authors.initials: GG
authors.lastname: Stefanini
authors.forename: Lorenz
authors.initials: L
authors.lastname: Räber
authors.forename: Stefan
authors.initials: S
authors.lastname: Stortecky
authors.forename: Steffen
authors.initials: S
authors.lastname: Gloekler
authors.forename: Ronald K
authors.initials: RK
authors.lastname: Binder
authors.forename: Peter
authors.initials: P
authors.lastname: Wenaweser
authors.forename: Aris
authors.initials: A
authors.lastname: Moschovitis
authors.forename: Ahmed A
authors.initials: AA
authors.lastname: Khattab
authors.forename: Lutz
authors.initials: L
authors.lastname: Buellesfeld
authors.forename: Marcel
authors.initials: M
authors.lastname: Zwahlen
authors.forename: Bernhard
authors.initials: B
authors.lastname: Meier
authors.forename: Peter
authors.initials: P
authors.lastname: Jüni
authors.forename: Stephan
authors.initials: S
authors.lastname: Windecker
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000740:Anemia / Q000175:diagnosis* / Q000453:epidemiology* / Q000401:mortality / Q000601:surgery; D019917:Blood Vessel Prosthesis Implantation; D002318:Cardiovascular Diseases / Q000175:diagnosis* / Q000453:epidemiology* / Q000401:mortality / Q000601:surgery; D054855:Drug-Eluting Stents; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009204:Myocardial Revascularization; D011379:Prognosis; D012307:Risk Factors; D016019:Survival Analysis; D013557:Switzerland; D013997:Time Factors; D016896:Treatment Outcome