Are amyotrophic lateral sclerosis patients cognitively normal?

Abstract

Background: Patients with ALS are often told that the disease spares cognition; however, recent evidence suggests deficits in frontal executive skills occur in a sizable minority of ALS patients. In many instances, the frontal executive deficits represent the co-occurrence of frontotemporal lobar dementia (FTLD) and ALS. Methods: Word generation, a simple frontal task that takes Results: Diminished word generation was found in one-third. Of the patients with abnormal word generation who agreed to further evaluation, nearly all were shown to meet research criteria for FTLD. In addition, one-quarter of the patients with normal word generation who agreed to further evaluation met research criteria for FTLD; these patients had new-onset personality changes. Conclusions: This study suggests that frontal executive deficits are present in half of ALS patients, many of whom meet strict research criteria for FTLD. Word generation tests are a useful screening tool in this cohort.