title: In a prospective observational study, influenza vaccination prevented hospitalization among older home care patients.
abstract: OBJECTIVE
  The aim of the study is (1) to describe the prevalence of vaccination against influenza in older home care patients and (2) to investigate the protective effect of influenza vaccination for hospitalization events.
  
  
  METHODS
  This is an observational study conducted in four large cohorts of elderly patients in home care during the 1998-1999, 1999-2000, 2000-2001, and 2001-2002 influenza seasons. We analyzed data from the Italian Silver Network Home Care project. A total of 2,201 patients were enrolled in the present study. The main outcome measures were prevalence of vaccination against influenza and the rate of hospitalization according to vaccination status and influenza season.
  
  
  RESULTS
  The rate of influenza vaccination was around 48% of the studied sample. During the follow-up including the peak of influenza and the total influenza season, 412 subjects (40%) were hospitalized among vaccinated compared to 610 subjects (59%) among not vaccinated (P<0.001). After adjusting for age, gender, location of home care program, and all the variables significantly different between vaccinated and not-vaccinated subjects, vaccinated subjects were less likely to be hospitalized compared to not-vaccinated subjects (OR, 0.73; 95% CI 0.60-0.90).
  
  
  CONCLUSIONS
  Vaccination against influenza has an important prognostic implication for frail geriatric patients living in the community.
authors.affiliation: Department of Gerontology-Geriatric and Physiatric, Catholic University of Sacred Heart, 00168 Rome, Italy. francesco_landi@rm.unicatt.it
authors.forename: Francesco
authors.initials: F
authors.lastname: Landi
authors.forename: Graziano
authors.initials: G
authors.lastname: Onder
authors.forename: Matteo
authors.initials: M
authors.lastname: Cesari
authors.forename: Andrea
authors.initials: A
authors.lastname: Russo
authors.forename: Christian
authors.initials: C
authors.lastname: Barillaro
authors.forename: Roberto
authors.initials: R
authors.lastname: Bernabei
authors.forename: G
authors.initials: G
authors.lastname: Gambassi
authors.forename: L
authors.initials: L
authors.lastname: Manigrasso
authors.forename: F
authors.initials: F
authors.lastname: Pagano
authors.forename: C
authors.initials: C
authors.lastname: Gobbi
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D016330:Frail Elderly; D015577:Geriatric Assessment / Q000379:methods; D006699:Home Care Services; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D007252:Influenza Vaccines / Q000008:administration & dosage*; D007251:Influenza, Human / Q000453:epidemiology / Q000517:prevention & control*; D007558:Italy / Q000453:epidemiology; D008297:Male; D011379:Prognosis; D011446:Prospective Studies; D012621:Seasons; D017678:Sex Distribution
chemical_list: D007252:Influenza Vaccines