TUESDAY, March 14, 2006 (HealthDay News) -- About a third of people with the degenerative motor neuron disease amyotrophic lateral sclerosis (ALS) showed signs of cognitive impairment, researchers report.
However, these cognitive deficits do not appear to affect survival, a new study finds.
Researchers at the Columbia University College of Physicians and Surgeons in New York City studied 40 ALS patients who were tested to assess their cognitive functioning. Of the 40 patients, 12 (30 percent) showed evidence of cognitive impairment, and nine of those 12 met criteria for dementia.
Reporting in the March issue of the Archives of Neurology, ALS patients who had dementia and those who did not showed no significant differences in terms of age, sex, education, memory loss, emotional stability, severity of disease, family history, or the site in their body where the onset of ALS was first detected.
Survival data for 38 of the 40 patients showed they lived an average of 3.4 years after they were tested for cognitive function. The researchers concluded that cognitive impairment and dementia did not appear to be associated with survival.
"Thirty percent of a consecutive series of patients with ALS demonstrated cognitive impairment, and nearly a quarter qualified for a neuropsychologic diagnosis of dementia," the study authors wrote. "Free recall, executive function and naming were most impaired in ALS patients with dementia."
They noted that dementia in the frontal lobes is the type believed to be associated with ALS and other motor neuron diseases. Future studies using testing and diagnostic criteria specific to that type of dementia may find an even higher percentage of ALS patients with cognitive impairment than uncovered in this study, the authors concluded.
More information
The U.S. National Institute of Neurological Disorders and Stroke has more about ALS.
