title: The impact of benzodiazepines on occurrence of pneumonia and mortality from pneumonia: a nested case-control and survival analysis in a population-based cohort.
abstract: OBJECTIVE
  Benzodiazepines have been associated with an increased incidence of infections, and mortality from sepsis, in the critically ill. Here, we determined the effect of community use of benzodiazepines on the occurrence of, and mortality following, pneumonia.
  
  
  METHODS
  A nested case-control study using 29 697 controls and 4964 cases of community-acquired pneumonia (CAP) from The Health Improvement Network, a UK primary care patient database (2001-2002), investigated the association between benzodiazepines and pneumonia occurrence using conditional logistic regression. Cox regression was then used to determine the impact of benzodiazepines on mortality in the 4964 cases of CAP. Results are presented as adjusted OR, adjusted HR and 95% CI.
  
  
  RESULTS
  Exposure to benzodiazepines was associated with an increased risk of pneumonia (OR 1.54, 95% CI 1.42 to 1.67). Individually diazepam, lorazepam and temazepam, but not chlordiazepoxide, were associated with an increased incidence of CAP. As a class, benzodiazepines were associated with increased 30-day (HR 1.22 (95% CI 1.06 to 1.39)) and long-term mortality (HR 1.32 (95% CI 1.19 to 1.47)) in patients with a prior diagnosis of CAP. Individually diazepam, chlordiazepoxide, lorazepam and temazepam affected long-term mortality in these patients.
  
  
  CONCLUSIONS
  Benzodiazepines were associated with an increased risk of, and mortality from, CAP. These hypothesis generating data suggest further research is required into the immune safety profile of benzodiazepines.
authors.affiliation: Division of Epidemiology and Public Health, University of Nottingham, Nottingham, UK.
authors.forename: Eneanya
authors.initials: E
authors.lastname: Obiora
authors.forename: Richard
authors.initials: R
authors.lastname: Hubbard
authors.forename: Robert D
authors.initials: RD
authors.lastname: Sanders
authors.forename: Puja R
authors.initials: PR
authors.lastname: Myles
mesh_terms: D000328:Adult; D000368:Aged; D001569:Benzodiazepines / Q000009:adverse effects*; D016022:Case-Control Studies; D017714:Community-Acquired Infections / Q000139:chemically induced; D005260:Female; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011014:Pneumonia / Q000139:chemically induced* / Q000401:mortality*; D016019:Survival Analysis; D055815:Young Adult
chemical_list: D001569:Benzodiazepines