title: Spectrum of epidemiological and clinical findings in patients with heart failure with preserved ejection fraction stratified by study design: a systematic review.
abstract: BACKGROUND
  Heart failure with preserved ejection fraction (HFpEF) represents a major global and economic burden, but its epidemiological, clinical, and outcome data have varied according to study design.
  
  
  RESULTS
  We conducted a systematic review of published HFpEF clinical trials and observational studies (community-based studies and registries) from August 1998 to July 2013 using PubMed and EMBASE databases. Two independent investigators manually screened and extracted relevant data. We included 62 articles (19 describing clinical trials, 12 describing community-based observational studies, and 31 describing registries). The ejection fraction (EF) cut-off values ranged widely for HFpEF from >40% to >55%. However, differences in EF cut-offs were not clearly associated with incidence and prevalence data across studies. Of all patients with heart failure in community studies, 33-84% had HFpEF, which tended to be higher than reported in registries. The HFpEF patients in included studies were primarily older, white (>70%) patients with hypertension (∼50-90%) and coronary artery disease (up to 60%). All-cause mortality and all-cause hospitalizations ranged from 13% to 23% (26-50 months follow-up) and 55% to 67% (37-50 months follow-up), respectively, in clinical trials; cardiovascular causes accounted for 70% of both outcomes. All-cause mortality tended to be higher in registries than in clinical trials and community-based observational studies up to 5 years into follow-up.
  
  
  CONCLUSIONS
  Important differences in EF thresholds, epidemiological indices, clinical profiles, treatment patterns, and outcomes exist across contemporary HFpEF clinical trials, observational studies, and registries. Precision in definition and inclusion of more uniform populations may facilitate improved profiling of HFpEF patients.
authors.affiliation: Brigham and Women's Hospital Heart & Vascular Center and Harvard Medical School, Boston, MA, USA.
authors.forename: Muthiah
authors.initials: M
authors.lastname: Vaduganathan
authors.affiliation: Bayer Pharma AG, Global Epidemiology, Berlin, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Michel
authors.affiliation: Research Evaluation Unit, Oxford PharmaGenesis, Oxford, UK.
authors.forename: Kathryn
authors.initials: K
authors.lastname: Hall
authors.affiliation: Research Evaluation Unit, Oxford PharmaGenesis, Oxford, UK.
authors.forename: Claire
authors.initials: C
authors.lastname: Mulligan
authors.affiliation: Department of Experimental and Applied Medicine - Section of Cardiovascular Diseases, University of Brescia, Brescia, Italy.
authors.forename: Savina
authors.initials: S
authors.lastname: Nodari
authors.affiliation: Center for Cardiovascular Innovation, Northwestern University Feinberg School of Medicine, 201 East Huron, Galter 3-150, Chicago, IL, USA.
authors.forename: Sanjiv J
authors.initials: SJ
authors.lastname: Shah
authors.affiliation: Dipartimento Cardiovascolare, Azienda Ospedaliera Papa Giovannni XXIII, Bergamo, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Senni
authors.affiliation: Department of Experimental and Applied Medicine - Section of Cardiovascular Diseases, University of Brescia, Brescia, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Triggiani
authors.affiliation: Division of Cardiology, Stony Brook University, Stony Brook, NY, USA.
authors.forename: Javed
authors.initials: J
authors.lastname: Butler
authors.affiliation: Center for Cardiovascular Innovation, Northwestern University Feinberg School of Medicine, 201 East Huron, Galter 3-150, Chicago, IL, USA.
authors.forename: Mihai
authors.initials: M
authors.lastname: Gheorghiade
mesh_terms: D002986:Clinical Trials as Topic / Q000379:methods / Q000592:standards; D006333:Heart Failure / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology / Q000628:therapy; D006801:Humans; D010043:Outcome and Process Assessment, Health Care; D018579:Patient Selection; D011379:Prognosis; D012042:Registries / Q000706:statistics & numerical data; D018570:Risk Assessment; D013318:Stroke Volume
keywords: Clinical trials; Epidemiology; Heart failure; Outcomes; Registries; Systematic review