title: Development of demographics and outcome of very old critically ill patients admitted to intensive care units.
abstract: OBJECTIVE
  To evaluate the development of demographics and outcome of very old (>80 years) critically ill patients admitted to intensive care units.
  
  
  METHODS
  All consecutive patients admitted to 41 Austrian intensive care units (ICUs) over an 11-year period.
  
  
  METHODS
  We performed a retrospective cohort study of prospectively collected data. To compare parameters over time, patients were divided into three groups (group I from 1998 until 2001, group II from 2002 to 2004, and group III from 2005 to 2008).
  
  
  RESULTS
  A total of 17,126 patients older than 80 years of age were admitted over the study period. The proportion of very old patients increased from 11.5% (I) to 15.3% (III) with a significant higher prevalence of females in all groups (on average 63.2%). Severity of illness also increased over time, even when corrected for age. Use of noninvasive mechanical ventilation increased over the years. However, risk-adjusted mortality rates [observed-to-expected (O/E) ratios] decreased from 1.14 [confidence interval (CI) 1.11-1.18] to 1.02 (CI 0.99-1.05). This improvement in outcome was confirmed on multivariate analysis: for every year delay in ICU admission, the odds to die decreased by 3%. Moreover, females exhibited a better outcome compared with males.
  
  
  CONCLUSIONS
  The relative and absolute numbers of very old patients increased over the study period, as did the severity of illness. Despite this, risk-adjusted hospital mortality improved over the study period. Females dominated in the very old patients and exhibited moreover a better outcome compared with males.
authors.affiliation: Department of Anesthesiology and General Intensive Care, Medical University of Vienna, Vienna, Austria. gerald.ihra@meduniwien.ac.at
authors.forename: Gerald C
authors.initials: GC
authors.lastname: Ihra
authors.forename: Judith
authors.initials: J
authors.lastname: Lehberger
authors.forename: Helene
authors.initials: H
authors.lastname: Hochrieser
authors.forename: Peter
authors.initials: P
authors.lastname: Bauer
authors.forename: Rene
authors.initials: R
authors.lastname: Schmutz
authors.forename: Barbara
authors.initials: B
authors.lastname: Metnitz
authors.forename: Philipp G H
authors.initials: PG
authors.lastname: Metnitz
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001317:Austria; D016009:Chi-Square Distribution; D016638:Critical Illness / Q000401:mortality; D003710:Demography; D005260:Female; D017052:Hospital Mortality / Q000639:trends; D006801:Humans; D007362:Intensive Care Units; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D012121:Respiration, Artificial / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012720:Severity of Illness Index; D012737:Sex Factors