title: Social deprivation, population dependency ratio and an extended hospital episode - Insights from acute medicine.
abstract: BACKGROUND
  Patients from deprived backgrounds have a higher in-patient mortality following an emergency medical admission; this study aimed to investigate the extent to which Deprivation status and the population Dependency Ratio influenced extended hospital episodes.
  
  
  METHODS
  All Emergency Medical admissions (75,018 episodes of 41,728 patients) over 12 years (2002-2013) categorized by quintile of Deprivation Index and Population Dependency Rates (proportion of non-working/working) were evaluated against length of stay (LOS). Patients with an Extended LOS (ELOS), >30 days, were investigated, by Deprivation status, Illness Severity and Co-morbidity status. Univariate and multi-variable risk estimates (Odds Rates or Incidence Rate Ratios) were calculated, using truncated Poisson regression.
  
  
  RESULTS
  Hospital episodes with ELOS had a frequency of 11.5%; their median LOS (IQR) was 55.0 (38.8, 97.6) days utilizing 57.6% of all bed days by all 75,018 emergency medical admissions. The Deprivation Index independently predicted the rate of such ELOS admissions; these increased approximately five-fold (rate/1000 population) over the Deprivation Quintiles with model adjusted predicted admission rates of for Q1 0.93 (95% CI: 0.86, 0.99), Q22.63 (95% CI: 2.55, 2.71), Q3 3.84 (95% CI: 3.77, 3.91), Q4 3.42 (95% CI: 3.37, 3.48) and Q5 4.38 (95% CI: 4.22, 4.54). Similarly the Population Dependency Ratio Quintiles (dependent to working structure of the population by small area units) independently predicted extended LOS admissions.
  
  
  CONCLUSIONS
  The admission of patients with an ELOS is strongly influenced by the Deprivation status and the population Dependency Ratio of the catchment area. These factors interact, with both high deprivation and Dependency cohorts having a major influence on the numbers of emergency medical admission patients with an extended hospital episode.
authors.affiliation: Medical Physics and Bioengineering Department, St James's Hospital, Dublin 8, Ireland.
authors.forename: Seán
authors.initials: S
authors.lastname: Cournane
authors.affiliation: Office of the CEO, St James's Hospital, Dublin 8, Ireland.
authors.forename: Ann
authors.initials: A
authors.lastname: Dalton
authors.affiliation: Department of Internal Medicine, St James's Hospital, Dublin 8, Ireland.
authors.forename: Declan
authors.initials: D
authors.lastname: Byrne
authors.affiliation: Department of Internal Medicine, St James's Hospital, Dublin 8, Ireland.
authors.forename: Richard
authors.initials: R
authors.lastname: Conway
authors.affiliation: Department of Internal Medicine, St James's Hospital, Dublin 8, Ireland.
authors.forename: Deirdre
authors.initials: D
authors.lastname: O'Riordan
authors.affiliation: School of Geographical and Earth Sciences, University of Glasgow, University Avenue, Glasgow G12 8QQ, UK.
authors.forename: Seamus
authors.initials: S
authors.lastname: Coveney
authors.affiliation: Department of Internal Medicine, St James's Hospital, Dublin 8, Ireland. Electronic address: bernardsilke@physicians.ie.
authors.forename: Bernard
authors.initials: B
authors.lastname: Silke
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015897:Comorbidity; D003710:Demography; D003858:Dependency, Psychological; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007494:Ireland; D007902:Length of Stay / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010343:Patient Admission / Q000706:statistics & numerical data*; D011379:Prognosis; D012044:Regression Analysis; D012720:Severity of Illness Index; D012944:Social Support; D012959:Socioeconomic Factors
keywords: Dependency Ratio; Deprivation Index; Emergency medical admission; Extended episode