Smell test predicts performance on delayed recall memory test in elderly with depression

Int J Geriatr Psychiatry. 2009 Apr;24(4):376-81. doi: 10.1002/gps.2132.

Abstract

Introduction: Elderly with depression are at increased risk for cognitive dysfunction and dementia. Smell tests are correlated with performance on cognitive tests in the elderly and therefore might serve as a screening test for cognitive impairment in depressed elderly.

Purpose: To assess the validity of the CC-SIT (Cross-Cultural Smell Identification Test) as a screening test for cognitive impairment in elderly with depression.

Methods: Forty-one patients, aged 60 and over, were assessed with the CC-SIT and CVLT (California Verbal Learning Test) after 3 months treatment of a Major Depressive Episode (DSM-IV) at the Day Hospital for Depression, Baycrest. Patients already diagnosed with dementia, or other psychiatric and neurological disorders, were excluded. Receiver Operating Characteristics (ROC) analysis was applied to assess the CC-SIT's accuracy in identifying individuals with impairment (2 SD below the mean for age and education or less) on CVLT delayed recall trials.

Results: Forty-one patients (33 women and eight men) were assessed. Mean age was 76.8 (SD: 6.5), mean HRSD scores before treatment was 22.0 (SD: 5.1). Nine patients had impairment on CVLT delayed recall measures. The area under the ROC curve was 0.776 (95% CI = 0.617-0.936).

Conclusions: Our results support the use of the CC-SIT as a screening tool for cognitive impairment among elderly with depression as an indicator for the need of a comprehensive neuropsychological evaluation. Replication with larger samples is necessary.

Publication types

  • Research Support, Non-U.S. Gov't
  • Validation Study

MeSH terms

  • Canada
  • Cognition Disorders / diagnosis*
  • Cognition Disorders / psychology
  • Dementia / diagnosis*
  • Dementia / psychology
  • Depressive Disorder / diagnosis*
  • Depressive Disorder / psychology
  • Diagnostic and Statistical Manual of Mental Disorders
  • Female
  • Humans
  • Male
  • Mental Recall / physiology*
  • Middle Aged
  • Neuropsychological Tests*
  • Predictive Value of Tests
  • ROC Curve
  • Risk Factors
  • Smell*