Are amyotrophic lateral sclerosis patients cognitively normal?

Neurology. 2003 Apr 8;60(7):1094-7. doi: 10.1212/01.wnl.0000055861.95202.8d.


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 <2 minutes, was tested in 100 consecutive patients with ALS seen in the authors' multidisciplinary clinic. Any patient with a prior dementia diagnosis was excluded from the study. A subset of 44 patients agreed to undergo further neuropsychological testing and clinical interview to confirm or deny a diagnosis of dementia.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Amyotrophic Lateral Sclerosis / epidemiology*
  • Amyotrophic Lateral Sclerosis / physiopathology
  • Cohort Studies
  • Dementia / diagnosis*
  • Dementia / epidemiology*
  • Dementia / physiopathology
  • Female
  • Frontal Lobe / physiopathology
  • Humans
  • Incidence
  • Male
  • Mass Screening / methods
  • Middle Aged
  • Neuropsychological Tests
  • Predictive Value of Tests
  • Verbal Behavior