title: Influence of influenza vaccination on recurrent hospitalization in patients with heart failure.
abstract: BACKGROUND
  The current study aimed to evaluate the influence of regular annual influenza vaccinations on cardiovascular (CV) death and heart failure-related hospitalizations (HFrH) in stable outpatients with heart failure with reduced ejection fraction.
  
  
  METHODS
  The Turkish research team-HF (TREAT-HF) is a network undertaking multicenter, observational cohort studies in HF. This study is a subgroup analysis of TREAT-HF outpatient cohorts who completed a questionnaire on influenza vaccination status and for whom follow-up data were available. A total of 656 patients with available follow-up data for CV death and HFrH including recurrent hospitalization were included in the study. Patients were classified into two groups: those who received regular influenza vaccination (40 %) and those who did not receive vaccination.
  
  
  RESULTS
  During a mean follow-up of 15 ±6 months, 113 (18 %) patients had CV death and 471 (72 %) patients had at least one HFrH. The CV death rate was similar in both groups of patients (16 vs. 19 %, p = 0.37), whereas, HFrH and recurrent HFrH were significantly less frequently encountered in patients who received regular influenza vaccination than in those who did not receive vaccination (43 vs. 92 % and 16 vs. 66 %, p < 0.001, respectively). In a multivariate Cox proportional hazards model - in addition to a few clinical factors - vaccination status (HR = 0.30, 95 % CI = 0.17-0.51, p < 0.001) and graduation from university (HR = 0.35, 95 % CI = 0.17-0.72, p = 0.004) remained independently associated with the risk of recurrent HFrH.
  
  
  CONCLUSIONS
  Regular influenza vaccination does not influence CV deaths; however, it decreases HFrH including recurrent episodes of HFrH in outpatients with heart failure with reduced ejection fraction.
authors.affiliation: Faculty of Medicine, Department of Cardiology, Cumhuriyet University, 58140, Sivas, Turkey. drhakkikaya84@gmail.com.
authors.forename: H
authors.initials: H
authors.lastname: Kaya
authors.affiliation: Faculty of Medicine, Department of Cardiology, Cumhuriyet University, 58140, Sivas, Turkey.
authors.forename: O
authors.initials: O
authors.lastname: Beton
authors.affiliation: Faculty of Medicine, Department of Cardiology, Sutcu Imam University, Kahramanmaras, Turkey.
authors.forename: G
authors.initials: G
authors.lastname: Acar
authors.affiliation: Cardiology Clinics, Yukses Ihtisas Training and Research Hospital, Ankara, Turkey.
authors.forename: A
authors.initials: A
authors.lastname: Temizhan
authors.affiliation: Faculty of Medicine, Department of Cardiology, Osmangazi University, Eskisehir, Turkey.
authors.forename: Y
authors.initials: Y
authors.lastname: Cavusoğlu
authors.affiliation: Cardiology Clinics, Ankara Numune Training and Research Hospital, Ankara, Turkey.
authors.forename: U
authors.initials: U
authors.lastname: Guray
authors.affiliation: Faculty of Medicine, Department of Cardiology, Ege University, Izmir, Turkey.
authors.forename: M
authors.initials: M
authors.lastname: Zoghi
authors.affiliation: Faculty of Medicine, Department of Cardiology, Koc University, Istanbul, Turkey.
authors.forename: D
authors.initials: D
authors.lastname: Ural
authors.affiliation: Cardiology Clinics, Siyami Ersek Thoracic and Cardiovascular Surgery Training and Research Hospital, Istanbul, Turkey.
authors.forename: A
authors.initials: A
authors.lastname: Ekmekci
authors.affiliation: Faculty of Medicine, Department of Cardiology, Adnan Menderes University, Aydın, Turkey.
authors.forename: H
authors.initials: H
authors.lastname: Gungor
authors.affiliation: Faculty of Medicine, Department of Cardiology, Marmara University, Istanbul, Turkey.
authors.forename: I
authors.initials: I
authors.lastname: Sari
authors.affiliation: Faculty of Medicine, Department of Cardiology, Baskent University, Ankara, Turkey.
authors.forename: D
authors.initials: D
authors.lastname: Oguz
authors.affiliation: Faculty of Medicine, Department of Cardiology, Cumhuriyet University, 58140, Sivas, Turkey.
authors.forename: H
authors.initials: H
authors.lastname: Yucel
authors.affiliation: Faculty of Medicine, Department of Cardiology, Cumhuriyet University, 58140, Sivas, Turkey.
authors.forename: A
authors.initials: A
authors.lastname: Zorlu
authors.affiliation: Faculty of Medicine, Department of Cardiology, Cumhuriyet University, 58140, Sivas, Turkey.
authors.forename: M B
authors.initials: MB
authors.lastname: Yilmaz
mesh_terms: D015897:Comorbidity; D016757:Death, Sudden, Cardiac / Q000453:epidemiology* / Q000517:prevention & control; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000401:mortality* / Q000517:prevention & control; D006801:Humans; D007252:Influenza Vaccines / Q000627:therapeutic use*; D007251:Influenza, Human / Q000401:mortality* / Q000517:prevention & control*; D008297:Male; D008875:Middle Aged; D010359:Patient Readmission / Q000706:statistics & numerical data*; D015995:Prevalence; D012307:Risk Factors; D014421:Turkey / Q000453:epidemiology; D014611:Vaccination / Q000706:statistics & numerical data*
chemical_list: D007252:Influenza Vaccines
keywords: Heart failure; Hospitalization; Influenza; Outpatients; Vaccination