title: Time trends in incidence and outcomes of hospitalizations for aspiration pneumonia among elderly people in Spain (2003-2013).
abstract: BACKGROUND
  Aspiration pneumonia (AP) is an infectious process causing high rates of mortality. The purpose of this study was: 1, to describe the incidence from 2003 to 2013 of AP hospitalizations; 2, to assess time trends in hospital outcomes variables, and; 3, to identify the factors independently associated with in-hospital mortality (IHM).
  
  
  METHODS
  A retrospective observational study using the Spanish National Hospital Database, with patients discharged between January 2003 and December 2013 was conducted. Inclusion criteria were: Subjects aged 75years or older whose medical diagnosis included AP events code according to the ICD-9-CM: 507.x in the primary diagnosis field. Patient variables, up to 14 discharge diagnoses per patient, and up to 20 procedures performed during the hospital stay (ICD-9-CM), Charlson Comorbidity Index, readmission, length of hospital stay (LOHS), and IHM were analyzed.
  
  
  RESULTS
  We included 111,319 admissions (53.13% women). LOHS decreased in both sexes (P<0.001) and was significantly higher in men (10.4±10.31 vs. 9.56±10.02days). Readmissions increased significantly in women during the study (13.94% in 2003 to 16.41% in 2013, P<0.001). In both sex, IHM was significantly higher in >94years old subjects (OR: 1.43, 95%CI 1.36-1.51) and in those with readmissions (OR: 1.20, 95%CI 1.15-1.23). For the entire population, time trend analyses showed a significant decrease in mortality from 2003 to 2013 (OR: 0.96, 95%CI 0.95-0.97).
  
  
  CONCLUSIONS
  Patients with AP are older, male, and have more comorbidities than those without AP. Over time, LOHS and IHM decreased in both sexes, but readmissions increased significantly in women.
authors.affiliation: Department of Physiotherapy, Occupational Therapy, Rehabilitation and Physical Medicine, Universidad Rey Juan Carlos, Alcorcón, Madrid, Spain. Electronic address: domingo.palacios@urjc.es.
authors.forename: Domingo
authors.initials: D
authors.lastname: Palacios-Ceña
authors.affiliation: Medicine and Surgery, Psychology, Preventive Medicine and Public Health, Medical Microbiology and Immunology and Nursing Department, Universidad Rey Juan Carlos, Alcorcón, Madrid, Spain. Electronic address: valentin.hernandez@urjc.es.
authors.forename: Valentín
authors.initials: V
authors.lastname: Hernández-Barrera
authors.affiliation: Medicine and Surgery, Psychology, Preventive Medicine and Public Health, Medical Microbiology and Immunology and Nursing Department, Universidad Rey Juan Carlos, Alcorcón, Madrid, Spain. Electronic address: ana.lopez@urjc.es.
authors.forename: Ana
authors.initials: A
authors.lastname: López-de-Andrés
authors.affiliation: Department of Physiotherapy, Occupational Therapy, Rehabilitation and Physical Medicine, Universidad Rey Juan Carlos, Alcorcón, Madrid, Spain. Electronic address: cesar.fernandez@urjc.es.
authors.forename: César
authors.initials: C
authors.lastname: Fernández-de-Las-Peñas
authors.affiliation: Department of Physiotherapy, Occupational Therapy, Rehabilitation and Physical Medicine, Universidad Rey Juan Carlos, Alcorcón, Madrid, Spain. Electronic address: maria.palacios@urjc.es.
authors.forename: María
authors.initials: M
authors.lastname: Palacios-Ceña
authors.affiliation: Respiratory Department, Hospital General Universitario Gregorio Marañón, Facultad de Medicina, Universidad Complutense de Madrid (UCM), Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain. Electronic address: javier.miguel@salud.madrid.org.
authors.forename: Javier
authors.initials: J
authors.lastname: de Miguel-Díez
authors.affiliation: Medicine and Surgery, Psychology, Preventive Medicine and Public Health, Medical Microbiology and Immunology and Nursing Department, Universidad Rey Juan Carlos, Alcorcón, Madrid, Spain. Electronic address: pilar.carrasco@urjc.es.
authors.forename: Pilar
authors.initials: P
authors.lastname: Carrasco-Garrido
authors.affiliation: Medicine and Surgery, Psychology, Preventive Medicine and Public Health, Medical Microbiology and Immunology and Nursing Department, Universidad Rey Juan Carlos, Alcorcón, Madrid, Spain. Electronic address: rodrigo.jimenez@urjc.es.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Jiménez-García
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D015897:Comorbidity / Q000639:trends*; D016208:Databases, Factual; D005260:Female; D017052:Hospital Mortality / Q000639:trends*; D006801:Humans; D015994:Incidence; D007902:Length of Stay / Q000639:trends*; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D010359:Patient Readmission / Q000639:trends*; D011015:Pneumonia, Aspiration / Q000453:epidemiology*; D012189:Retrospective Studies; D012307:Risk Factors; D017678:Sex Distribution; D013030:Spain / Q000453:epidemiology
keywords: Aged; Aspiration; Epidemiology; Hospital mortality; Pneumonia; Pulmonary