title: The impact of prior outpatient ACE inhibitor use on 30-day mortality for patients hospitalized with community-acquired pneumonia.
abstract: BACKGROUND
  Recent studies suggest that angiotensin-converting enzyme (ACE) inhibitors may have beneficial effects for patients at risk for some types of infections. We examined the effect of prior outpatient use of ACE inhibitors on mortality for patients hospitalized with community-acquired pneumonia.
  
  
  METHODS
  A retrospective cohort study conducted at two tertiary teaching hospitals. Eligible subjects were admitted with a diagnosis of, had a chest x-ray consistent with, and had a discharge ICD-9 diagnosis of pneumonia. Subjects were excluded if they were "comfort measures only" or transferred from another acute care hospital. Subjects were considered to be on a medication if they were taking it at the time of presentation.
  
  
  RESULTS
  Data was abstracted on 787 subjects at the two hospitals. Mortality was 9.2% at 30-days and 13.6% at 90-days. At presentation 52% of subjects were low risk, 34% were moderate risk, and 14% were high risk. In the multivariable conditional logistic regression analysis, after adjusting for potential confounders, the use of ACE inhibitors at presentation (odds ratio 0.44, 95% confidence interval 0.22-0.89) was significantly associated with 30-day mortality.
  
  
  CONCLUSIONS
  Prior outpatient use of an ACE inhibitor was associated with decreased mortality in patients hospitalized with community-acquired pneumonia despite their use being associated with comorbid illnesses likely to contribute to increased mortality. Confirmatory studies are needed, as well as research to determine the mechanism(s) of this protective effect.
authors.affiliation: VERDICT Research Center, Audie L Murphy VA Hospital, San Antonio, Texas, USA. mortensen@verdict.uthscsa.edu
authors.forename: Eric M
authors.initials: EM
authors.lastname: Mortensen
authors.forename: Marcos I
authors.initials: MI
authors.lastname: Restrepo
authors.forename: Antonio
authors.initials: A
authors.lastname: Anzueto
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Pugh
mesh_terms: D000328:Adult; D000368:Aged; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use*; D015331:Cohort Studies; D017714:Community-Acquired Infections / Q000401:mortality / Q000517:prevention & control; D005260:Female; D006784:Hospitals, Teaching / Q000706:statistics & numerical data; D006801:Humans; D007297:Inpatients; D008297:Male; D008875:Middle Aged; D010045:Outpatients; D011014:Pneumonia / Q000401:mortality* / Q000517:prevention & control*; D012189:Retrospective Studies; D020379:Risk Adjustment; D012307:Risk Factors
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors