Association Between 2 Measures of Cognitive Instrumental Activities of Daily Living and Their Relation to the Montreal Cognitive Assessment in Persons With Stroke.

OBJECTIVES

To explore the relation between a computer adaptive functional cognitive questionnaire and a performance-based measure of cognitive instrumental activities of daily living (C-IADL) and to determine whether the Montreal Cognitive Assessment (MoCA) at admission can identify those with C-IADL difficulties at discharge.

DESIGN

Prospective cohort study.

SETTING

Acute inpatient rehabilitation unit of an academic medical center.

PARTICIPANTS

Inpatients (N=148) with a diagnosis of stroke (mean age, 68y; median, 13d poststroke) who had mild cognitive and neurological deficits.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Admission cognitive status was assessed by the MoCA. C-IADL at discharge was assessed by the Executive Function Performance Test (EFPT) bill paying task and Activity Measure of Post-Acute Care (AM-PAC) Applied Cognition scale.

RESULTS

Greater cognitive impairment on the MoCA was associated with more assistance on the EFPT bill paying task (ρ=-.63; P<.01) and AM-PAC Applied Cognition scale (ρ=-.43; P<.01). This relation was nonsignificant for higher MoCA scores and EFPT bill paying task scores. The AM-PAC Applied Cognition scale and the EFPT bill paying task had low agreement in classifying functional performance (Cohen's κ=.20). A receiver operating characteristic curve identified optimal MoCA cutoff scores of 20 and 21 for classifying EFPT bill paying task status and AM-PAC Applied Cognition scale status, respectively. For values above 20 and 21, sensitivity increased whereas specificity decreased for classifying functional deficits. Approximately one third of the participants demonstrated C-IADL deficits on at least 1 C-IADL measure at discharge despite having a MoCA score of ≥26 at admission.

CONCLUSIONS

Questionnaire and performance-based methods of assessment appear to yield different estimates of C-IADL. Low MoCA scores (<20) are more likely to identify those with C-IADL deficits on the EFPT bill paying task. The results suggest that C-IADL should be assessed in those who have mild or no cognitive difficulties at admission.