title: Acute and chronic diseases as part of multimorbidity in acutely hospitalized older patients.
abstract: BACKGROUND
  To describe the prevalence of multimorbidity and to study the association between acute and chronic diseases in acutely hospitalized older patients
  
  
  METHODS
  Prospective cohort study conducted between 2006 and 2008 in three teaching hospitals in the Netherlands. 639 patients aged 65 years and older, hospitalized for >48 h were included. Two physicians scored diseases, using ICD-9 codes. Chronic multimorbidity was defined as the presence of ≥2 chronic diseases, and acute multimorbidity as ≥1 acute diseases upon pre-existent chronic diseases. Logistic regression analyses were conducted to analyse cluster associations between a chronic index disease and the concurrent chronic or acute disease, corrected for age and sex.
  
  
  RESULTS
  The mean age of patients was 78 years, over 50% had ADL impairments. Prevalence of chronic multimorbidity was 69%, and acute multimorbidity was present in 88%. Hypertension (OR 1.16; 95% CI 1.08-1.24), diabetes (type I or type 2) (OR 1.12; 95% CI 1.04-1.21), heart failure (OR 1.25; 95% CI 1.14-1.38) and COPD (OR 1.19; 95% CI 1.05-1.34) were associated with acute renal failure. Hypertension (OR 1.10; 95% CI 1.04-1.17) and atrial fibrillation (OR 1.17; 95% CI 1.08-1.27) were associated with an adverse drug event. Gastro-intestinal bleeding was clustered with atrial fibrillation (OR 1.11; 95% CI 1.04-1.19) and gastric ulcer (OR 1.16; 95% CI 1.07-1.25).
  
  
  CONCLUSIONS
  Both acute and chronic multimorbidity was frequently present in hospitalized older patients. We identified specific associations between acute and chronic diseases. There is a need for strategies addressing multimorbidity during the exacerbation of chronic diseases.
authors.affiliation: Academic Medical Center, Department of Internal Medicine, Section of Geriatric Medicine, University of Amsterdam, Amsterdam, The Netherlands. Electronic address: b.m.vanes@amc.uva.nl.
authors.forename: Bianca M
authors.initials: BM
authors.lastname: Buurman
authors.affiliation: Academic Medical Center, Department of Internal Medicine, Section of Vascular medicine, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Wijnanda J
authors.initials: WJ
authors.lastname: Frenkel
authors.affiliation: Academic Medical Center, Department of Medical Informatics, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Ameen
authors.initials: A
authors.lastname: Abu-Hanna
authors.affiliation: Academic Medical Center, Department of Internal Medicine, Section of Geriatric Medicine, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Juliette L
authors.initials: JL
authors.lastname: Parlevliet
authors.affiliation: Academic Medical Center, Department of Internal Medicine, Section of Geriatric Medicine, University of Amsterdam, Amsterdam, The Netherlands; University Medical Center Groningen, University Center of Geriatric Medicine Groningen, The Netherlands.
authors.forename: Sophia E
authors.initials: SE
authors.lastname: de Rooij
mesh_terms: D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D002908:Chronic Disease; D015897:Comorbidity; D005260:Female; D006760:Hospitalization; D006801:Humans; D007388:Internal Medicine; D016015:Logistic Models; D008297:Male; D009426:Netherlands / Q000453:epidemiology; D016017:Odds Ratio; D015995:Prevalence; D011446:Prospective Studies
keywords: Comorbidity; Hospitalization; Internal medicine; Multimorbidity; Older adults