Detection of cognitive impairment and dementia using the animal fluency test: the DECIDE study

To evaluate the performance of a one-minute screening test measured against a validated 10-minute screening test for mild cognitive impairment (MCI) in detecting CI in patients aged > or = 65 years with two or more vascular risk factors (VRF).

Patients (n=1523) aged 65 years or older without documented CI symptoms or dementia with two or more VRF participated in this study set in Canadian primary care practice. Baseline data was collected, followed by the 1-minute animal fluency (AF) test and the 10-minute Montreal Cognitive Assessment (MoCA). Physicians (n=122) completed case reports during patient interviews and reported their diagnostic impression. AF test sensitivity, specificity, and accuracy in predicting a positive MoCA was assessed.

Study sample mean age was 79.7 years, 55% were female, 97.6% were Caucasian and 75% had < or = 12 years of education. The AF test and MoCA detected CI in 52 and 56 percent of the study population, respectively. The AF test demonstrated sensitivity, specificity, and accuracy in predicting a positive MoCA of 67 percent each. Physicians diagnostic impression of MCI was reported for 37% of patients, and of dementia for 6%.

In an elderly population with at least two VRF, using AF can be useful in detecting previously unknown symptoms of CI or dementia. Screening for CI in this high risk population is warranted to assist physician recognition of early CI. The short AF administration time favours its incorporation into clinical practice.