title: Cognitive impairment in heart failure: issues of measurement and etiology.
abstract: BACKGROUND
  Clinicians need easy methods of screening for cognitive impairment in patients with heart failure. If correlates of cognitive impairment could be identified, more patients with early cognitive impairment could be treated before the problem interfered with adherence to treatment.
  
  
  OBJECTIVE
  To describe cognitive impairment in patients with heart failure, to explore the usefulness of 4 measures of cognitive impairment, and to assess correlates of cognitive impairment.
  
  
  METHODS
  A descriptive, correlational design was used. Four screening measures of cognition were assessed in 42 patients with heart failure: Commands subtest and Complex Ideational Material subtest of the Boston Diagnostic Aphasia Examination, Mini-Mental State Examination, and Draw-a-Clock Test. Cognitive impairment was defined as performance less than the standardized (T-score) cutoff point on at least 1 of the 4 measures. Possible correlates of cognitive impairment included age, education, hypotension, fluid overload (serum osmolality < 269 mOsm/kg), and dehydration (serum osmolality > or = 295 mOsm/kg).
  
  
  RESULTS
  Cognitive impairment was detected in 12 (28.6%) of 42 participants. The 4 screening tests varied in effectiveness, but the Draw-a-Clock Test indicated impairment in 50% of the 12 impaired patients. A summed standardized score for the 4 measures was not significantly associated with age, education, hypotension, fluid overload, or dehydration in this sample.
  
  
  CONCLUSIONS
  Cognitive impairment is relatively common in patients with heart failure. The Draw-a-Clock Test was most useful in detecting cognitive impairment, although it cannot be used to detect problems with verbal learning or delayed recall and should not be used as the sole screening method for patients with heart failure. Correlates of cognitive impairment require further study.
authors.affiliation: School of Nursing, University of Pennsylvania, USA.
authors.forename: Barbara
authors.initials: B
authors.lastname: Riegel
authors.forename: Jill A
authors.initials: JA
authors.lastname: Bennett
authors.forename: Andra
authors.initials: A
authors.lastname: Davis
authors.forename: Beverly
authors.initials: B
authors.lastname: Carlson
authors.forename: John
authors.initials: J
authors.lastname: Montague
authors.forename: Howard
authors.initials: H
authors.lastname: Robin
authors.forename: Dale
authors.initials: D
authors.lastname: Glaser
mesh_terms: D000328:Adult; D016009:Chi-Square Distribution; D003072:Cognition Disorders / Q000175:diagnosis / Q000209:etiology*; D005260:Female; D006333:Heart Failure / Q000150:complications*; D006801:Humans; D008297:Male