title: Patients with chronic heart failure encountered in daily clinical practice are different from the "typical" patient enrolled in therapeutic trials.
abstract: BACKGROUND
  The aim of this study was to compare the clinical characteristics of patients enrolled in randomized clinical trials on congestive heart failure treatment with those of real-world patients encountered in daily clinical practice.
  
  
  METHODS
  We searched the Cochrane review methodology, Medline and SilverPlatter databases to obtain the clinical characteristics of both patients enrolled in therapeutic clinical trials and real-world patients with heart failure. We selected 27 clinical trials, and 8 prospective epidemiological studies or registries published between 1987 and 2001 which enrolled 53,859 and 18,207 patients, respectively.
  
  
  RESULTS
  On average, compared to real-world heart failure patients, patients enrolled in clinical trials were younger (63 +/- 10 vs 75 +/- 11 years respectively, p < 0.0001), and more likely to be male (72 vs 54% respectively, p < 0.0001). Clinical trial patients showed a lower ejection fraction (26 +/- 7 vs 38 +/- 15% respectively, p < 0.0001) but a lower prevalence of NYHA functional class III-IV (62 vs 75% respectively, p < 0.0001) than real-world patients. In clinical trial patients, the prevalence of ischemic heart disease (67 vs 42% respectively, p < 0.0001) and a history of previous myocardial infarction (62 vs 42% respectively, p < 0.0001) were higher than in real-world patients. Conversely, the prevalence of chronic atrial fibrillation (12 vs 31% respectively, p < 0.0001) and of diabetes (22 vs 24% respectively, p < 0.02) was lower in trial patients than in real-world patients.
  
  
  CONCLUSIONS
  Our data suggest that most clinical trials on congestive heart failure, on which the guidelines for clinical practice are based, have generally included patients who are not representative of the whole spectrum of patients actually managed in clinical practice.
authors.affiliation: Cardiology Unit, Cardiovascular Science Department, S. Maria della Misericordia Hospital, Udine, Italy. lbadan@tin.it
authors.forename: Luigi P
authors.initials: LP
authors.lastname: Badano
authors.forename: Andrea
authors.initials: A
authors.lastname: Di Lenarda
authors.forename: Paolo
authors.initials: P
authors.lastname: Bellotti
authors.forename: Maria C
authors.initials: MC
authors.lastname: Albanese
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Sinagra
authors.forename: Paolo M
authors.initials: PM
authors.lastname: Fioretti
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D002908:Chronic Disease; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000453:epidemiology / Q000503:physiopathology / Q000628:therapy*; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D010045:Outpatients / Q000706:statistics & numerical data; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D015995:Prevalence; D011446:Prospective Studies; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data; D012737:Sex Factors; D013318:Stroke Volume / Q000502:physiology; D016896:Treatment Outcome; D016277:Ventricular Function, Left / Q000502:physiology