Introduction: Functional outcome after stroke is predicted to be unfavorable in patients with dementia. However, sometimes it is difficult to know prestroke cognitive function in patients with aphasia and other cognitive impairments.
Hypothesis: Cerebral atrophy in patients without dementia is a predictive marker for functional outcome following intensive rehabilitation after ischemic stroke.
Methods: In patients aged 65 years or older with acute ischemic stroke in our stroke center, those who were moved to a rehabilitation unit and underwent intensive rehabilitation for 1–3 months were selected. Patients with prestroke modified Rankin scale ≥ 2 or with diagnosed dementia were excluded. Severity of cerebral atrophy was assessed on axial brain MRI performed with routine protocols in an acute phase. Hippocampal atrophy, cortical atrophy, and subcortical atrophy were separately assessed using the visual rating scales. Functional status was measured using the Functional Independence Measure (FIM) scale after 2 weeks from onset (FIM 1), when a patient was moved to a rehabilitation unit (FIM 2), and at the time of discharge (FIM 3). We retrospectively investigated the association between cerebral atrophy and FIM scores.
Results: In a total of 197 patients (119 men and 78 women; median age, 74 years), the average time interval between stroke onset and transfer to the rehabilitation unit was 33.8 days and the length of stay in the unit was 58.7 days. FIM 1–3 scores were strongly associated with age, initial stroke severity, and cerebral atrophy. In the multivariate analyses, subcortical atrophy was significantly associated with FIM 1 (P=0.02), FIM 2 (P=0.003) and FIM 3 (P=0.008), and hippocampal atrophy was associated with FIM 3 (P=0.01) but not with FIM 1 and FIM 2 after adjusting for age, sex, stroke severity, and rehabilitation periods. Cortical atrophy was not associated with FIM scores after adjusting for age and other related factors.
Conclusion: In elderly patients without apparent dementia, subcortical atrophy and hippocampal atrophy assessed on axial brain MRI with simple visual ratings were remarkable predictors of poor functional outcome after ischemic stroke.