title: De-escalation versus continuation of empirical antimicrobial therapy in community-acquired pneumonia.
abstract: To compare mortality between de-escalation and continued empirical treatment in patients with community-acquired pneumonia.
  
  
  
  Using a nationwide administrative database, we identified adult patients with community-acquired pneumonia caused by Streptococcus pneumoniae, other streptococci, Haemophilus influenzae, Klebsiella pneumoniae, or Escherichia coli (n = 10,231) or of unknown etiology (n = 8247), discharged between July 2010 and March 2013. De-escalation was determined by the spectrum and number of antimicrobials at day 4. We used propensity score matching to obtain 489 pairs of de-escalation and continuation groups among pathogen-identified patients and 278 pairs among culture-negative patients to compare mortalities.
  
  
  
  In the pathogen-identified patients, de-escalation was noninferior to continuation in 15-day mortality [5.3% in de-escalation versus 4.3% in continuation, a difference of 1.0% (95% confidence interval, -1.7% to 3.7%)] and in-hospital mortality [8.0% in de-escalation versus 8.8% in continuation, a difference of -0.8% (95% confidence interval, -4.3% to 2.7%)]. In the culture-negative cases, de-escalation was noninferior to continuation in terms of 15-day mortality but not in terms of in-hospital mortality.
  
  
  
  Among patients with community-acquired pneumonia of specific etiology, de-escalation was noninferior to continuation of empirical treatment, suggesting that de-escalation is a safe strategy and supporting current recommendations. Safety of de-escalation in culture-negative cases is questionable.
authors.affiliation: Department of Clinical Epidemiology and Health Economics, School of Public Health, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 1130033, Japan. Electronic address: yamana-tky@umin.ac.jp.
authors.forename: Hayato
authors.initials: H
authors.lastname: Yamana
authors.affiliation: Department of Clinical Epidemiology and Health Economics, School of Public Health, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 1130033, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Matsui
authors.affiliation: Department of Clinical Epidemiology and Health Economics, School of Public Health, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 1130033, Japan; Department of Emergency and Critical Care Medicine, Nippon Medical School Tama Nagayama Hospital, 1-7-1 Nagayama, Tama-shi, Tokyo 2068512, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Tagami
authors.affiliation: Department of Clinical Epidemiology and Health Economics, School of Public Health, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 1130033, Japan; Department of Respiratory Medicine, National Center for Global Health and Medicine, 1-21-1 Toyama, Shinjuku-ku, Tokyo 1628655, Japan.
authors.forename: Junko
authors.initials: J
authors.lastname: Hirashima
authors.affiliation: Department of Health Policy and Informatics, Tokyo Medical and Dental University Graduate School of Medicine, 1-5-45 Yushima, Bunkyo-ku, Tokyo 1138510, Japan.
authors.forename: Kiyohide
authors.initials: K
authors.lastname: Fushimi
authors.affiliation: Department of Clinical Epidemiology and Health Economics, School of Public Health, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 1130033, Japan.
authors.forename: Hideo
authors.initials: H
authors.lastname: Yasunaga
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000890:Anti-Infective Agents / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D017714:Community-Acquired Infections / Q000188:drug therapy* / Q000453:epidemiology / Q000382:microbiology; D004334:Drug Administration Schedule; D024901:Drug Resistance, Multiple, Bacterial; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D018410:Pneumonia, Bacterial / Q000188:drug therapy* / Q000453:epidemiology
chemical_list: D000890:Anti-Infective Agents
keywords: Anti-infective agents; Bacterial pneumonia; Drug resistance