title: Incidence, direct costs and duration of hospitalization of patients hospitalized with community acquired pneumonia: A nationwide retrospective claims database analysis.
abstract: BACKGROUND
  Community-acquired pneumonia (CAP) is one of the most common acute infections associated with a substantial clinical and economic burden. There have been few studies assessing incidence rate, duration of hospitalization, and costs of hospitalized CAP by age and care-setting.
  
  
  METHODS
  A retrospective study was conducted using a nationwide Dutch database containing healthcare claims data of 16.7 million inhabitants. Patients with at least one claim with a discharge diagnosis of CAP between January 2008 and December 2011 were selected. The main outcome measures considered were the incidence rate, duration of hospitalization, and the direct costs of hospitalized CAP stratified by age and care-setting.
  
  
  RESULTS
  In total, 195,372 CAP cases were included in the analysis resulting in an average incidence of 295 per 100,000 population per year. Sixty-three percent (123,357) of the included patients were hospitalized for 1 or more nights, of which 5.9% (n=7241) spent at least one night in the Intensive Care Unit (ICU). Overall, these 123,357 patients spent 824,985 days in the hospital of which 48,324 were spent on the ICU. The mean duration of hospitalization of ICU patients and general ward patients was 15.2 days and 6.2 days, respectively. The total costs related to all 195,372 CAP episodes during these 4 years were €711 million, with the majority (76%) occurring among those aged 50 years and older. Median (and mean) costs were dependent on age and type of care with costs ranging from €344 (€482) per episode for 0-9 year olds treated in the outpatient hospital setting up to €10,284 (€16,374) per episode for 50-64 year olds admitted to the ICU.
  
  
  CONCLUSIONS
  There is a large variation in terms of incidence, disease burden and costs across different age groups and the treatment setting. Effective interventions, targeted at older adults, to prevent pneumonia could reduce the (financial) burden due to pneumonia.
authors.affiliation: Pfizer bv, Capelle a/d IJssel, The Netherlands; Unit of PharmacoEpidemiology & PharmacoEconomics (PE2), Department of Pharmacy, University of Groningen, Groningen, The Netherlands. Electronic address: mark.rozenbaum@pfizer.com.
authors.forename: Mark H
authors.initials: MH
authors.lastname: Rozenbaum
authors.affiliation: Julius Centre for Health Sciences and Primary Care, University Medical Centre Utrecht, Utrecht,The Netherlands.
authors.forename: Marie-Josee J
authors.initials: MJ
authors.lastname: Mangen
authors.affiliation: Julius Centre for Health Sciences and Primary Care, University Medical Centre Utrecht, Utrecht,The Netherlands; Department of Respiratory Medicine, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Susanne M
authors.initials: SM
authors.lastname: Huijts
authors.affiliation: Departments of Internal Medicine, Infectious Diseases, and Pulmonary Diseases & Tuberculosis, University Medical Center Groningen (UMCG), University of Groningen, The Netherlands.
authors.forename: Tjip S
authors.initials: TS
authors.lastname: van der Werf
authors.affiliation: Unit of PharmacoEpidemiology & PharmacoEconomics (PE2), Department of Pharmacy, University of Groningen, Groningen, The Netherlands; Institute for Science in Healthy Aging & healthcaRE (SHARE), University Medical Center Groningen (UMCG), Groningen, The Netherlands.
authors.forename: Maarten J
authors.initials: MJ
authors.lastname: Postma
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D017714:Community-Acquired Infections / Q000191:economics / Q000453:epidemiology*; D016208:Databases, Factual; D005260:Female; D017048:Health Care Costs / Q000706:statistics & numerical data*; D006760:Hospitalization / Q000191:economics* / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D011014:Pneumonia / Q000145:classification / Q000191:economics / Q000453:epidemiology*; D012189:Retrospective Studies; D055815:Young Adult
keywords: Community acquired pneumonia; Costs; Database; Duration of hospitalization; Incidence; Length of stay; Pneumonia