title: Are patients admitted to hospitals from care homes dehydrated? A retrospective analysis of hypernatraemia and in-hospital mortality.
abstract: OBJECTIVE
  To compare risks of hypernatraemia on admission to hospital in persons who were with those who were not identified as care home residents and evaluate the association of hypernatraemia with in-hospital mortality.
  
  
  METHODS
  Retrospective observational study.
  
  
  METHODS
  A National Health Service Trust in London.
  
  
  METHODS
  A total of 21,610 patients aged over 65 years whose first admission to the Trust was between 1 January 2011 and 31 December 2013.
  
  
  METHODS
  Hypernatraemia on admission (plasma Na > 145 mmol/L) and in-hospital death.
  
  
  RESULTS
  Patients admitted from care homes had 10-fold higher prevalence of hypernatraemia than those from their own homes (12.0% versus 1.3%, respectively; odds ratio [OR]: 10.5, 95% confidence interval [CI]: 8.43-13.0). Of those with hypernatraemia, nine in 10 cases were associated with nursing home ECOHOST residency (attributable fraction exposure: 90.5%), and the population attributable fraction of hypernatraemia on admission associated with care homes was 36.0%. After correcting for age, gender, mode of admission and dementia, care home residents were significantly more likely to be admitted with hypernatraemia than were own-home residents (adjusted odds ratio [AOR]: 5.32, 95% CI: 3.85-7.37). Compared with own-home residents, care home residents were also at about a two-fold higher risk of in-hospital mortality compared with non-care home residents (AOR: 1.97, 95% CI: 1.59-2.45). Consistent with evidence that hypernatraemia is implicated in higher mortality, the association of nursing homes with in-hospital mortality was attenuated after adjustment for it (AOR: 1.61, 95% CI: 1.26-2.06).
  
  
  CONCLUSIONS
  Patients admitted to hospital from care homes are commonly dehydrated on admission and, as a result, appear to experience significantly greater risks of in-hospital mortality.
authors.affiliation: Barnet and Chase Farm NHS Trust, London EN5 3DJ, UK.
authors.forename: Anthony
authors.initials: A
authors.lastname: Wolff
authors.affiliation: Department of Sociology, Christchurch College, University of Oxford, Oxford OX1 3UQ, UK.
authors.forename: David
authors.initials: D
authors.lastname: Stuckler
authors.affiliation: ECOHOST, London School of Hygiene and Tropical Medicine, London WC1H 9SH, UK martin.mckee@lshtm.ac.uk.
authors.forename: Martin
authors.initials: M
authors.lastname: McKee
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003681:Dehydration / Q000150:complications* / Q000401:mortality; D004552:Elder Abuse / Q000706:statistics & numerical data*; D004739:England / Q000453:epidemiology; D005260:Female; D017052:Hospital Mortality / Q000639:trends; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D006955:Hypernatremia / Q000209:etiology / Q000401:mortality*; D008297:Male; D009735:Nursing Homes; D016017:Odds Ratio; D012189:Retrospective Studies; D012307:Risk Factors
keywords: care homes; dehydration; hypernatraemia; older people