title: Profiling dizziness in older primary care patients: an empirical study.
abstract: BACKGROUND
  The diagnostic approach to dizzy, older patients is not straightforward as many organ systems can be involved and evidence for diagnostic strategies is lacking. A first differentiation in diagnostic subtypes or profiles may guide the diagnostic process of dizziness and can serve as a classification system in future research. In the literature this has been done, but based on pathophysiological reasoning only.
  
  
  OBJECTIVE
  To establish a classification of diagnostic profiles of dizziness based on empirical data.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  417 consecutive patients of 65 years and older presenting with dizziness to 45 primary care physicians in the Netherlands from July 2006 to January 2008.
  
  
  METHODS
  We performed tests, including patient history, and physical and additional examination, previously selected by an international expert panel and based on an earlier systematic review. We used the results of these tests in a principal component analysis for exploration, data-reduction and finally differentiation into diagnostic dizziness profiles.
  
  
  RESULTS
  Demographic data and the results of the tests yielded 221 variables, of which 49 contributed to the classification of dizziness into six diagnostic profiles, that may be named as follows: "frailty", "psychological", "cardiovascular", "presyncope", "non-specific dizziness" and "ENT". These explained 32% of the variance.
  
  
  CONCLUSIONS
  Empirically identified components classify dizziness into six profiles. This classification takes into account the heterogeneity and multicausality of dizziness and may serve as starting point for research on diagnostic strategies and can be a first step in an evidence based diagnostic approach of dizzy older patients.
authors.affiliation: Department of Family Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. j.dros@amc.uva.nl
authors.forename: Jacquelien
authors.initials: J
authors.lastname: Dros
authors.forename: Otto R
authors.initials: OR
authors.lastname: Maarsingh
authors.forename: Daniëlle A W M
authors.initials: DA
authors.lastname: van der Windt
authors.forename: Frans J
authors.initials: FJ
authors.lastname: Oort
authors.forename: Gerben
authors.initials: G
authors.lastname: ter Riet
authors.forename: Sophia E J A
authors.initials: SE
authors.lastname: de Rooij
authors.forename: François G
authors.initials: FG
authors.lastname: Schellevis
authors.forename: Henriëtte E
authors.initials: HE
authors.lastname: van der Horst
authors.forename: Henk C P M
authors.initials: HC
authors.lastname: van Weert
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D004244:Dizziness / Q000145:classification / Q000175:diagnosis*; D036262:Empirical Research; D019317:Evidence-Based Medicine; D006801:Humans; D009426:Netherlands; D011320:Primary Health Care; D025341:Principal Component Analysis