title: Hemoglobin concentration is an independent determinant of heart failure in acute coronary syndromes: cohort analysis of 2310 patients.
abstract: BACKGROUND
  Anemia is an important determinant of heart failure and death after ST elevation myocardial infarction (STEMI). The frequency of anemia and its impact on these outcomes across the range of acute coronary syndromes (ACS), however, have not been defined.
  
  
  METHODS
  This is a cohort study of 2310 patients with ACS stratified by quartiles of admission hemoglobin concentration [Hb]): Q1, <12.5 g/dL; Q2, 12.5-13.6 g/dL; Q3, 13.7-14.7 g/dL; Q4, >14.7 g/dL.
  
  
  RESULTS
  There were 29.7% of women and 23.2% of men who were anemic. Rates of STEMI increased across [Hb] quartile groups from 25.0% (Q1) to 35.5% (Q4) as rates of unstable angina decreased from 52.0% (Q1) to 40.7% (Q4) (P < .0005). Despite this, rates of left ventricular failure (LVF) were inversely related to [Hb] in all diagnostic groups, patients with unstable angina (Q1, 14.2%; Q4, 4.4%; P < .0005) showing a similar trend to patients with non-STEMI (Q1, 26.8%; Q4, 10.4%; P < .0005) and STEMI (Q1, 33.8%; Q4, 20.6%; P < .0005). The age-adjusted odds of LVF in Q4 compared with Q1 were 0.64 (95% confidence interval, 0.45-0.90). Inhospital cardiac mortality was 3.0% and was not influenced by [Hb].
  
  
  CONCLUSIONS
  Anemia is a common comorbidity in patients presenting with ACS, and it is a powerful independent determinant of LVF. The association with LVF occurs not only in STEMI but also in less severe diagnostic groups.
authors.affiliation: Department of Cardiology, Newham University Hospital, London, United Kingdom. andrew.archbold@bartsandthelondon.nhs.uk
authors.forename: R Andrew
authors.initials: RA
authors.lastname: Archbold
authors.forename: Dauda
authors.initials: D
authors.lastname: Balami
authors.forename: Abdul
authors.initials: A
authors.lastname: Al-Hajiri
authors.forename: Abdel
authors.initials: A
authors.lastname: Suliman
authors.forename: Reg
authors.initials: R
authors.lastname: Liew
authors.forename: Jackie
authors.initials: J
authors.lastname: Cooper
authors.forename: Kulasegarum
authors.initials: K
authors.lastname: Ranjadayalan
authors.forename: Charles J
authors.initials: CJ
authors.lastname: Knight
authors.forename: Andrew
authors.initials: A
authors.lastname: Deaner
authors.forename: Adam D
authors.initials: AD
authors.lastname: Timmis
mesh_terms: D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D000740:Anemia / Q000150:complications; D000789:Angina, Unstable / Q000097:blood / Q000150:complications; D002303:Cardiac Output, Low / Q000209:etiology*; D002318:Cardiovascular Diseases / Q000097:blood* / Q000150:complications* / Q000401:mortality; D015331:Cohort Studies; D004562:Electrocardiography; D005260:Female; D006454:Hemoglobins / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood / Q000150:complications / Q000175:diagnosis; D009994:Osmolar Concentration; D011446:Prospective Studies; D013577:Syndrome; D018487:Ventricular Dysfunction, Left / Q000209:etiology
chemical_list: D006454:Hemoglobins