title: Hospitalization in community-dwelling persons with Alzheimer's disease: frequency and causes.
abstract: OBJECTIVE
  To examine the rates of and risk factors for acute hospitalization in a prospective cohort of older community-dwelling patients with Alzheimer's disease (AD).
  
  
  METHODS
  Longitudinal patient registry.
  
  
  METHODS
  AD research center.
  
  
  METHODS
  Eight hundred twenty-seven older persons with AD.
  
  
  METHODS
  Acute hospitalization after AD research center visit was determined from a Medicare database. Risk factor variables included demographics, dementia-related, comorbidity and diagnoses and were measured in interviews and according to Medicare data.
  
  
  RESULTS
  Of the 827 eligible patients seen at the ADRC during 1991 to 2006 (median follow-up 3.0 years), 542 (66%) were hospitalized at least once, and 389 (47%) were hospitalized two or more times, with a median of 3 days spent in the hospital per person-year. Leading reasons for admission were syncope or falls (26%), ischemic heart disease (17%), gastrointestinal disease (9%), pneumonia (6%), and delirium (5%). Five significant independent risk factors for hospitalization were higher comorbidity (hazard ratio (HR)=1.87, 95% confidence interval (CI)=1.57-2.23), previous acute hospitalization (HR=1.65, 95% CI=1.37-1.99), older age (HR=1.51, 95% CI=1.26-1.81), male sex (HR=1.27, 95% CI=1.04-1.54), and shorter duration of dementia symptoms (HR=1.26, 95% CI=1.02-1.56). Cumulative risk of hospitalization increased with number of risk factors present at baseline: 38% with zero factors, 57% with one factor, 70% with two or three factors, and 85% with four or five factors (P(trend) <.001).
  
  
  CONCLUSIONS
  In a community-dwelling population with generally mild AD, hospitalization is frequent, occurring in two-thirds of participants over a median follow-up time of 3 years. With these results, clinicians may be able to identify dementia patients at high risk for hospitalization.
authors.affiliation: Aging Brain Center, Institute for Aging Research, Hebrew SeniorLife, Boston, Massachusetts, USA. jrudolph@partners.org
authors.forename: James L
authors.initials: JL
authors.lastname: Rudolph
authors.forename: Nicole M
authors.initials: NM
authors.lastname: Zanin
authors.forename: Richard N
authors.initials: RN
authors.lastname: Jones
authors.forename: Edward R
authors.initials: ER
authors.lastname: Marcantonio
authors.forename: Tamara G
authors.initials: TG
authors.lastname: Fong
authors.forename: Frances M
authors.initials: FM
authors.lastname: Yang
authors.forename: Liang
authors.initials: L
authors.lastname: Yap
authors.forename: Sharon K
authors.initials: SK
authors.lastname: Inouye
mesh_terms: D000058:Accidental Falls / Q000706:statistics & numerical data; D000367:Age Factors; D000368:Aged; D000544:Alzheimer Disease / Q000453:epidemiology*; D015897:Comorbidity; D003693:Delirium / Q000453:epidemiology; D005260:Female; D005767:Gastrointestinal Diseases / Q000453:epidemiology; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008404:Massachusetts / Q000453:epidemiology; D017202:Myocardial Ischemia / Q000453:epidemiology; D011014:Pneumonia / Q000453:epidemiology; D011446:Prospective Studies; D012042:Registries; D012307:Risk Factors; D012737:Sex Factors; D013575:Syncope / Q000453:epidemiology