title: Community-acquired pneumonia episode costs by age and risk in commercially insured US adults aged ≥50 years.
abstract: BACKGROUND
  Community-acquired pneumonia (CAP) causes substantial clinical and economic burden. While several studies have reported the cost to treat CAP, there is little information on the cost to treat by age, risk profile, and hospitalization in US adults aged ≥50 years.
  
  
  OBJECTIVE
  To quantify the cost, from a payer perspective, of treating CAP at the episode level, stratified by age, risk profile, and hospitalization.
  
  
  METHODS
  A retrospective study of claims data from a large US health plan (1 January 2006-31 December 2008) was conducted. Patients aged ≥50 years having at least one medical claim with a primary diagnosis for pneumonia were identified. A CAP episode was defined as the period between the first and last pneumonia ICD-9 code with a chest X-ray claim. Episode-level variables included risk stratum based on presence of an immunocompromising/chronic condition, age group, number and length of inpatient and outpatient CAP episodes, and all-cause and CAP-related healthcare costs (adjusted to 2011 costs).
  
  
  RESULTS
  Among the 27,659 study patients, 28,575 CAP episodes (20,454 outpatient; 8,121 inpatient) occurred. Mean age of patients with a CAP episode was 62.6. Low-risk patients accounted for 44.4 % of all CAP episodes. Mean CAP episode length was 31.8 days for an inpatient episode and 10.2 days for an outpatient episode. Mean all-cause total healthcare cost for an inpatient CAP episode ranged from $11,148 to $51,219 depending on risk stratum and age group. Mean outpatient episode-related costs were much lower than inpatient episode-related costs.
  
  
  CONCLUSIONS
  Cost to treat CAP requiring hospitalization is high regardless of age or the presence of underlying comorbidities. Given that almost half of the patients in this study did not have traditional risk factors for CAP, it is clear that better preventative strategies are needed.
authors.affiliation: Market Access, Pfizer Inc., Collegeville, PA 19426, USA.
authors.forename: Reiko
authors.initials: R
authors.lastname: Sato
authors.forename: Gabriel
authors.initials: G
authors.lastname: Gomez Rey
authors.forename: Stephanie
authors.initials: S
authors.lastname: Nelson
authors.forename: Brett
authors.initials: B
authors.lastname: Pinsky
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D017714:Community-Acquired Infections / Q000191:economics* / Q000628:therapy; D005260:Female; D017048:Health Care Costs / Q000706:statistics & numerical data*; D006760:Hospitalization / Q000191:economics* / Q000706:statistics & numerical data*; D006801:Humans; D007348:Insurance, Health / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D011014:Pneumonia / Q000191:economics* / Q000628:therapy*; D012189:Retrospective Studies; D012307:Risk Factors; D014481:United States