title: Frequent use of the hospital emergency department is indicative of high use of other health care services.
abstract: OBJECTIVE
  We sought to determine the proportion of emergency department patients who frequently use the ED and to compare their frequency of use of other health care services at non-ED sites.
  
  
  METHODS
  A computerized patient database covering all ambulatory visits and hospital admissions at all care facilities in the county of Stockholm, Sweden, was used. Frequent ED patients were defined as those making 4 or more visits in a 12-month period.
  
  
  RESULTS
  Frequent users comprised 4% of total ED patients, accounting for 18% of the ED visits. The ED was the only source of ambulatory care for 13% of frequent versus 27% of rare ED users (1 ED visit). Primary care visits were made by 72% of frequent ED users versus 57% by rare ED visitors. The corresponding figures for hospital admission were 80% and 36%, respectively. Frequent ED visitors were also more likely to use other care facilities repeatedly: their odds ratio (adjusted for age and sex) was 3.43 (95% confidence interval [CI] 3.10 to 3.78) for 5 or more primary care visits and 29.98 (95% CI 26.33 to 34.15) for 5 or more hospital admissions. In addition, heavy users had an elevated mortality (standardized mortality ratio 1.55; 95% CI 1.26 to 1.90).
  
  
  CONCLUSIONS
  High ED use patients are also high users of other health care services, presumably because they are sicker than average. A further indication of serious ill health is their higher than expected mortality. This knowledge might be helpful for care providers in their endeavors to find appropriate ways of meeting the needs of this vulnerable patient category.
authors.affiliation: Department of Clinical Neuroscience, Karolinska Hospital, Stockholm, Sweden. helen.hansagi@cspo.sll.se
authors.forename: H
authors.initials: H
authors.lastname: Hansagi
authors.forename: M
authors.initials: M
authors.lastname: Olsson
authors.forename: S
authors.initials: S
authors.lastname: Sjöberg
authors.forename: Y
authors.initials: Y
authors.lastname: Tomson
authors.forename: S
authors.initials: S
authors.lastname: Göransson
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000553:Ambulatory Care / Q000706:statistics & numerical data*; D002648:Child; D002675:Child, Preschool; D016208:Databases, Factual; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005260:Female; D006296:Health Services / Q000706:statistics & numerical data*; D006300:Health Services Misuse / Q000706:statistics & numerical data; D006302:Health Services Research; D006304:Health Status; D006779:Hospitals, Public / Q000706:statistics & numerical data; D006785:Hospitals, University / Q000706:statistics & numerical data; D006786:Hospitals, Urban / Q000706:statistics & numerical data; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D009026:Mortality; D020380:Needs Assessment; D016017:Odds Ratio; D010343:Patient Admission / Q000706:statistics & numerical data*; D011320:Primary Health Care / Q000706:statistics & numerical data; D017678:Sex Distribution; D013548:Sweden / Q000453:epidemiology