title: Identification of possible determinants of inpatient mortality using Classification and Regression Tree (CART) analysis in hospitalized oldest old patients.
abstract: Current demographic trends suggest that there will be increasing numbers of older people in the future. Relatively little information is available regarding factors which influence mortality in the acutely unwell oldest old. This study uses the CART technique on data relating to the oldest old, to identify potential predictors of inpatient mortality in patients over 90 years old admitted acutely to the hospital due to various medical emergencies in two UK centers. The sample included 393 patients aged 90 years and older, with 67.5% females and 32.5% males and a mean age of 91.1 years. We aimed to generate hypotheses in order to identify potential acute illness prognostic indicators of inpatient mortality in this age group. The factors identified in this analysis which were associated with inpatient mortality in this patient population were raised serum urea concentration (>13.95 mmol/L), low oxygen saturation levels (<94%), hyponatremia (<128 mmol/L), and raised white cell count (>17 × 10(9)/L). The predictability of using these cut off points in inpatient as well as early in-hospital death should be validated in future studies.
authors.affiliation: Department of Medicine for the Elderly, Woodend Hospital, Eday Road, Aberdeen AB15 6XS, UK. cbutchart@nhs.net
authors.forename: Catherine
authors.initials: C
authors.lastname: Butchart
authors.forename: Firat
authors.initials: F
authors.lastname: Ismailoglu
authors.forename: Phyo Kyaw
authors.initials: PK
authors.lastname: Myint
authors.forename: Patrick
authors.initials: P
authors.lastname: Musonda
authors.forename: Claire J
authors.initials: CJ
authors.lastname: Lunt
authors.forename: Yogish
authors.initials: Y
authors.lastname: Pai
authors.forename: Roy L
authors.initials: RL
authors.lastname: Soiza
authors.forename: V J
authors.initials: VJ
authors.lastname: Rayward-Smith
mesh_terms: D000369:Aged, 80 and over / Q000706:statistics & numerical data*; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007297:Inpatients / Q000706:statistics & numerical data; D007958:Leukocyte Count; D008297:Male; D015233:Models, Statistical; D010100:Oxygen / Q000097:blood; D011446:Prospective Studies; D012964:Sodium / Q000097:blood; D013223:Statistics as Topic / Q000379:methods; D006113:United Kingdom / Q000453:epidemiology; D014508:Urea / Q000097:blood
chemical_list: D014508:Urea; D012964:Sodium; D010100:Oxygen