title: Understanding NHS hospital admissions in England: linkage of Hospital Episode Statistics to the Hertfordshire Cohort Study.
abstract: BACKGROUND
  concern over the sustainability of the National Health Service (NHS) is often focussed on rising numbers of hospital admissions, particularly among older people. Hospital admissions are enumerated routinely by the Hospital Episode Statistics (HES) Service, but published data do not allow individual-level service use to be explored. This study linked information on Hertfordshire Cohort Study (HCS) participants with HES inpatient data, with the objective of describing patterns and predictors of admissions among individuals.
  
  
  METHODS
  2,997 community-dwelling men and women aged 59-73 years completed a baseline HCS assessment between 1998 and 2004; HES and mortality data to 31 March 2010 were linked with the HCS database. This paper describes patterns of hospital use among the cohort at both the admission and individual person level.
  
  
  RESULTS
  the cohort experienced 8,741 admissions; rates were 391 per 1,000 person-years among men (95% CI: 380, 402) and 327 among women (95% CI: 316, 338), P < 0.0001 for gender difference. A total of 1,187 men (75%) and 981 women (69%) were admitted to hospital at least once; among these, median numbers of admissions were 3 in men (inter-quartile range, (IQR): 1, 6) and 2 in women (IQR: 1, 5). Forty-eight percent of those ever admitted had experienced an emergency admission and 70% had been admitted overnight.
  
  
  CONCLUSIONS
  It is possible to link routinely collected HES data with detailed information from a cohort study. Hospital admission is common among community-dwelling 'young-old' men and women. These linked datasets will facilitate research into lifecourse determinants of hospital admission and inform strategies to manage demand on the NHS.
authors.affiliation: MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton SO16 6YD, UK.
authors.forename: Shirley J
authors.initials: SJ
authors.lastname: Simmonds
authors.affiliation: MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton SO16 6YD, UK.
authors.forename: Holly E
authors.initials: HE
authors.lastname: Syddall
authors.affiliation: Faculty of Health Sciences, University of Southampton, Southampton SO17 1BJ, UK.
authors.forename: Bronagh
authors.initials: B
authors.lastname: Walsh
authors.affiliation: Centre for Research on Ageing, University of Southampton, Southampton SO17 1BJ, UK.
authors.forename: Maria
authors.initials: M
authors.lastname: Evandrou
authors.affiliation: MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton SO16 6YD, UK.
authors.forename: Elaine M
authors.initials: EM
authors.lastname: Dennison
authors.affiliation: MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton SO16 6YD, UK.
authors.forename: Cyrus
authors.initials: C
authors.lastname: Cooper
authors.affiliation: MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton SO16 6YD, UK Academic Geriatric Medicine, University of Southampton, Southampton SO16 6YD, UK.
authors.forename: Avan
authors.initials: A
authors.lastname: Aihie Sayer
mesh_terms: D000368:Aged; D016208:Databases, Factual; D004632:Emergency Medical Services / Q000639:trends; D004739:England / Q000453:epidemiology; D005260:Female; D015276:Health Care Rationing / Q000639:trends; D006295:Health Resources / Q000706:statistics & numerical data / Q000639:trends*; D006301:Health Services Needs and Demand / Q000639:trends; D006302:Health Services Research; D006801:Humans; D007902:Length of Stay / Q000639:trends; D008297:Male; D008498:Medical Record Linkage; D008875:Middle Aged; D009026:Mortality / Q000639:trends; D010343:Patient Admission / Q000639:trends*; D013222:State Medicine / Q000639:trends*; D013997:Time Factors
keywords: Hospital Episode Statistics; data linkage; healthcare burden; hospital admissions; older people