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

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. Copyright © 2008 John Wiley & Sons, Ltd.