title: Multi-Morbidity in Hospitalised Older Patients: Who Are the Complex Elderly?
abstract: BACKGROUND
  No formal definition for the "complex elderly" exists; moreover, these older patients with high levels of multi-morbidity are not readily identified as such at point of hospitalisation, thus missing a valuable opportunity to manage the older patient appropriately within the hospital setting.
  
  
  OBJECTIVE
  To empirically identify the complex elderly patient based on degree of multi-morbidity.
  
  
  METHODS
  Retrospective observational study using administrative data.
  
  
  METHODS
  English hospitals during the financial year 2012-13.
  
  
  METHODS
  All admitted patients aged 65 years and over.
  
  
  METHODS
  By using exploratory analysis (correspondence analysis) we identify multi-morbidity groups based on 20 target conditions whose hospital prevalence was ≥ 1%.
  
  
  RESULTS
  We examined a total of 2788900 hospital admissions. Multi-morbidity was highly prevalent, 62.8% had 2 or more of the targeted conditions while 4.7% had six or more. Multi-morbidity increased with age from 56% (65-69yr age-groups) up to 67% (80-84yr age-group). The average multi-morbidity was 3.2±1.2 (SD). Correspondence analysis revealed 3 distinct groups of older patients. Group 1 (multi-morbidity ≤2), associated with cancer and/or metastasis; Group 2 (multi-morbidity of 3, 4 or 5), associated with chronic pulmonary disease, lung disease, rheumatism and osteoporosis; finally Group 3 with the highest level of multi-morbidity (≥6) and associated with heart failure, cerebrovascular accident, diabetes, hypertension and myocardial infarction.
  
  
  CONCLUSIONS
  By using widely available hospital administrative data, we propose patients in Groups 2 and 3 to be identified as the complex elderly. Identification of multi-morbidity patterns can help to predict the needs of the older patient and improve resource provision.
authors.affiliation: Dr Foster Unit at Imperial, Dept. Primary Care and Public Health, School of Public Health, Imperial College London, Reynolds Building, St. Dunstan's Road, London, W6 6RP, United Kingdom.
authors.forename: Milagros
authors.initials: M
authors.lastname: Ruiz
authors.affiliation: Dr Foster Unit at Imperial, Dept. Primary Care and Public Health, School of Public Health, Imperial College London, Reynolds Building, St. Dunstan's Road, London, W6 6RP, United Kingdom.
authors.forename: Alex
authors.initials: A
authors.lastname: Bottle
authors.affiliation: Department of Medicine for the Elderly, Cambridge Wing, St Mary's Campus, Imperial College London, Praed Street, London, W2 1NY, United Kingdom.
authors.forename: Susannah
authors.initials: S
authors.lastname: Long
authors.affiliation: Dr Foster Unit at Imperial, Dept. Primary Care and Public Health, School of Public Health, Imperial College London, Reynolds Building, St. Dunstan's Road, London, W6 6RP, United Kingdom.
authors.forename: Paul
authors.initials: P
authors.lastname: Aylin
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006333:Heart Failure / Q000401:mortality; D017052:Hospital Mortality; D006760:Hospitalization; D006801:Humans; D006973:Hypertension / Q000401:mortality; D007902:Length of Stay; D008297:Male; D009017:Morbidity; D009203:Myocardial Infarction / Q000401:mortality; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D020521:Stroke / Q000401:mortality