title: Timing of oseltamivir administration and outcomes in hospitalized adults with pandemic 2009 influenza A(H1N1) virus infection.
abstract: BACKGROUND
  Data on the clinical effectiveness of oseltamivir in patients with pandemic 2009 influenza A(H1N1) (A[H1N1]) virus infection are scarce. We aimed to determine the effect of timing of oseltamivir administration on outcomes in hospitalized adults with A(H1N1).
  
  
  METHODS
  Observational analysis of a prospective cohort of adults hospitalized with laboratory-confirmed A(H1N1) was performed at 13 Spanish hospitals. Time from onset of symptoms to oseltamivir administration was the independent variable. Outcomes were duration of fever, hospital length of stay (LOS), need for mechanical ventilation, and mortality during hospitalization. Multivariate logistic regression was used to describe the association between the independent variable and the outcomes.
  
  
  RESULTS
  Five hundred thirty-eight hospitalized patients with A(H1N1) were studied. The median time from onset of symptoms to oseltamivir administration was 3 days (interquartile range [IQR], 2-5 days). With regard to outcomes, the median duration of fever was 2 days (IQR, 1-3 days), the median LOS was 5 days (IQR, 3-8 days), 49 patients (9.1%) underwent mechanical ventilation, and 11 patients (2%) died during hospitalization. In univariate analysis, prolonged duration of fever (above the median), prolonged LOS (above the median), need for mechanical ventilation, and mortality all increased with time to oseltamivir administration (χ(2) test for trend P = .001, P ≤ .001, P = .008, and P = .001, respectively). After adjustment for confounding factors, time from onset of symptoms to oseltamivir administration (+ 1-day increase) was associated with a prolonged duration of fever (OR, 1.10; 95% CI, 1.02-1.19), prolonged LOS (OR, 1.07; 95% CI, 1.00-1.15), and higher mortality (OR, 1.20; 95% CI, 1.06-1.35).
  
  
  CONCLUSIONS
  Timely oseltamivir administration has a beneficial effect on outcomes in hospitalized adults with A(H1N1), even in those who are admitted beyond 48 h after onset of symptoms.
authors.affiliation: Departments of Infectious Diseases from the Hospital Universitari de Bellvitge-IDIBELL, University of Barcelona, Barcelona, Spain.
authors.forename: Diego
authors.initials: D
authors.lastname: Viasus
authors.affiliation: Hospital Universitario La Paz-IDIPAZ, Madrid, Spain.
authors.forename: José Ramón
authors.initials: JR
authors.lastname: Paño-Pardo
authors.affiliation: Hospital Universitario Virgen del Rocío, Sevilla, Spain.
authors.forename: Jerónimo
authors.initials: J
authors.lastname: Pachón
authors.affiliation: Hospital Universitario Son Dureta, Palma de Mallorca, Spain.
authors.forename: Melchor
authors.initials: M
authors.lastname: Riera
authors.affiliation: Hospital Universitario 12 de Octubre, Madrid, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: López-Medrano
authors.affiliation: Hospital Son Llàtzer, Palma de Mallorca, Spain.
authors.forename: Antoni
authors.initials: A
authors.lastname: Payeras
authors.affiliation: Hospital Universitario Marqués de Valdecilla, Santander, Spain.
authors.forename: M Carmen
authors.initials: MC
authors.lastname: Fariñas
authors.affiliation: Hospital Universitario Clinic, Barcelona, Spain.
authors.forename: Asunción
authors.initials: A
authors.lastname: Moreno
authors.affiliation: Hospital Universitario Virgen Macarena, Sevilla, Spain.
authors.forename: Jesús
authors.initials: J
authors.lastname: Rodríguez-Baño
authors.affiliation: Hospital San Pedro-CIBIR, Logroño, Spain.
authors.forename: José Antonio
authors.initials: JA
authors.lastname: Oteo
authors.affiliation: SCIAS-Hospital de Barcelona, Barcelona, Spain.
authors.forename: Lucia
authors.initials: L
authors.lastname: Ortega
authors.affiliation: Hospital Universitario Reina Sofía-IMIBIC, University of Córdoba, Córdoba, Spain.
authors.forename: Julián
authors.initials: J
authors.lastname: Torre-Cisneros
authors.affiliation: Hospital Parc Tauli, Sabadell, Spain.
authors.forename: Ferrán
authors.initials: F
authors.lastname: Segura
authors.affiliation: Departments of Infectious Diseases from the Hospital Universitari de Bellvitge-IDIBELL, University of Barcelona, Barcelona, Spain. Electronic address: jcarratala@ub.edu.
authors.forename: Jordi
authors.initials: J
authors.lastname: Carratalà
mesh_terms: D000998:Antiviral Agents / Q000008:administration & dosage / Q000627:therapeutic use; D015331:Cohort Studies; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype; D007251:Influenza, Human / Q000188:drug therapy* / Q000453:epidemiology* / Q000401:mortality; D007297:Inpatients; D007902:Length of Stay; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D053139:Oseltamivir / Q000008:administration & dosage* / Q000627:therapeutic use*; D058873:Pandemics; D011446:Prospective Studies; D012121:Respiration, Artificial; D012189:Retrospective Studies; D013030:Spain; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000998:Antiviral Agents; D053139:Oseltamivir