In a study of 40 patients with amyotrophic lateral sclerosis (ALS), about one-third showed evidence of cognitive impairment, but these deficits did not appear to be related to survival, according to a study in the March issue of Archives of Neurology.
ALS, commonly referred to as Lou Gehrig disease, is a progressive disorder characterized by the loss of muscle function and the atrophy (wasting away) of muscle tissue. ALS is primarily a disorder involving the motor neurons, which control muscles and movement in the body, but new evidence suggests it also may have an impact on cognition (thinking, learning and memory), according to background information in the article. Previous research has estimated that anywhere from 2 to 52 percent of patients with ALS also experience cognitive impairment.
Gregory A. Rippon, M.D., M.S., and colleagues at the Columbia University College of Physicians and Surgeons, New York, analyzed 40 consecutive patients with ALS who were evaluated at neurologists' offices between August 1991 and August 1992. Participants underwent examinations and testing to gauge their cognitive functioning and verify the diagnosis and history of their disease, including whether symptoms were first detected in muscles of the throat, jaw, tongue or face (bulbar onset) or those in the arms (limb onset). The researchers selected a control group of 80 individuals without ALS, matched to the ALS patients by age, gender and education, from a series of patients referred to a memory disorder clinic from 1992 to 2003.