title: Costs associated with influenza-related hospitalization in the elderly.
abstract: Seasonal influenza epidemics remain a considerable burden in adults, especially in those at higher risk of complications. The aim of this study was to determine the costs associated with influenza-related hospitalization in patients aged ≥65 y admitted to 20 hospitals from 7 Spanish regions during the 2013-14 and 2014-15 influenza seasons. Bivariate analysis was used to compare costs in vaccinated and unvaccinated cases. Costs were calculated according to the Spanish National Health System diagnosis-related group tables for influenza and other respiratory system conditions (GRD 89 and GRD 101). A total of 728 confirmed influenza cases were recorded: 52.9% were male, 46.7% were aged 75-84 years, and 49.3% received influenza vaccine ≥15 d prior to hospital admission. Influenza-related mean hospitalization costs (MHC) were € 1,184,808 in unvaccinated and € 1,152,333 in vaccinated cases (2.75% lower). Influenza vaccination showed significant protection against ICU admission (OR 0.35, 95%CI 0.21-0.59; p < 0001); mechanical ventilation (OR 0.56, 95%CI 0.39-0.80; p = 0.002); secondary bacterial pneumonia (OR 0.61, 95%CI 0.39-0.98; p = 0.04) and a higher degree of dependence (OR 0.74, 95%CI 0.55-0.99; p = 0.04). No association was observed for the Charlson comorbidity index or the mean hospital stay. Although influenza vaccination of the elderly may not achieve significant savings in mean hospitalization costs, it may lessen the degree of severity and avoid complications.
authors.affiliation: a CIBER Epidemiología y Salud Pública (CIBERESP), Instituto de Salud Carlos III , Madrid , Spain.|b Department of Medicine , Public Health Unit. University of Barcelona , Barcelona , Spain.|c Public Health Agency of Catalonia , Barcelona , Spain.
authors.forename: Núria
authors.initials: N
authors.lastname: Torner
authors.affiliation: c Public Health Agency of Catalonia , Barcelona , Spain.
authors.forename: Encarna
authors.initials: E
authors.lastname: Navas
authors.affiliation: a CIBER Epidemiología y Salud Pública (CIBERESP), Instituto de Salud Carlos III , Madrid , Spain.
authors.forename: Núria
authors.initials: N
authors.lastname: Soldevila
authors.affiliation: a CIBER Epidemiología y Salud Pública (CIBERESP), Instituto de Salud Carlos III , Madrid , Spain.
authors.forename: Diana
authors.initials: D
authors.lastname: Toledo
authors.affiliation: d Epidemiology Unit , Corporació Sanitària i Universitaria Parc Taulí , Sabadell , Spain.
authors.forename: Gemma
authors.initials: G
authors.lastname: Navarro
authors.affiliation: a CIBER Epidemiología y Salud Pública (CIBERESP), Instituto de Salud Carlos III , Madrid , Spain.|e Preventive Medicine and Public Health Department , University Hospital Virgen del Rocio , Seville , Spain.
authors.forename: Aurea
authors.initials: A
authors.lastname: Morillo
authors.affiliation: a CIBER Epidemiología y Salud Pública (CIBERESP), Instituto de Salud Carlos III , Madrid , Spain.|f Preventive Medicine and Public Health Department , University Hospital of Valme , Seville , Spain.
authors.forename: Maria José
authors.initials: MJ
authors.lastname: Pérez
authors.affiliation: a CIBER Epidemiología y Salud Pública (CIBERESP), Instituto de Salud Carlos III , Madrid , Spain.|b Department of Medicine , Public Health Unit. University of Barcelona , Barcelona , Spain.
authors.forename: Angela
authors.initials: A
authors.lastname: Domínguez
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D005260:Female; D017048:Health Care Costs; D006760:Hospitalization / Q000191:economics*; D006801:Humans; D007251:Influenza, Human / Q000191:economics*; D008297:Male; D013030:Spain
keywords: Influenza; cost; elderly; hospitalization; immunization