Executive Function Deficits in Acute Stroke

Zinn S, Bosworth HB, Hoenig HM, Swartzwelder HS. Executive function deficits in acute stroke.

Objectives

To establish the frequency of executive dysfunction during acute hospitalization for stroke and to examine the relationship of that dysfunction to stroke severity and premorbid characteristics.

Design

Inception cohort study.

Setting

Inpatient wards at a Veterans Affairs hospital.

Participants

Consecutive sample of inpatients with radiologically or neurologically confirmed stroke. Final sample included 47 patients screened for aphasia and capable of neuropsychologic testing. Two nonstroke inpatient control samples (n=10 each) with either transient ischemic attack (TIA) or multiple stroke risk factors were administered the same research procedure and tests.

Interventions

Not applicable.

Main Outcome Measures

Composite cognitive impairment ratio (CIR), calculated from 8 scores indicative of executive function on 6 neuropsychologic tests by dividing number of tests completed into the number of scores falling below cutoff point, defined as 1.5 standard deviations below normative population mean.

Results

Stroke patients had a mean CIR of .61, compared with .48 for TIAs and .44 for stroke-risk-only. Analysis of variance revealed that CIRs of stroke-risk-only patients but not TIAs were lower than those of the stroke patients (P=.02). Impairment frequencies were at least 50% for stroke patients on most test scores. The Symbol Digit Modalities Test (75% impairment) and a design fluency measure distinguished stroke from nonstroke patients. CIR was not related to stroke severity in the stroke patient sample, but was related to estimated premorbid intelligence.

Conclusions

Executive function deficits are common in stroke patients. The data suggest that limitations in information processing due to these deficits may require environmental and procedural accommodations to increase rehabilitation benefit.