A longitudinal study of the evolution of cognitive function and affective state in patients with amyotrophic lateral sclerosis.

OBJECTIVES: The study aimed to evaluate cognitive function and emotional reactivity in 18 patients with ALS, compared to 19 matched controls, and assess their evolution over a 12-month period. METHODS: 18 ALS patients and 19 matched controls were included, and assessed at inclusion, six months and twelve months later. Depression was evaluated with the Geriatric Depression Scale, and cognitive function with the Folstein Mini Mental State. A battery of psychometric tests (Wisconsin Card Sorting Test (WCST), the numerical Empan test, the Trail-making test, the Boston Naming Test, the 15-word Rey memory test, the Benton visual retention test and the Raven Progressive Matrix) was used to measure frontal processing and non-frontal function. Emotional reactivity was measured with the film-evoked emotions test. RESULTS: ALS patients were significantly more depressed than controls, as measured on the Geriatric Depression Scale, and depression increased over the study period. There was a very mild defect in cognitive function, and a performance deficit in the Trail-making test, a measure of frontal processing. These deficits, unlike neuromuscular function and depression, did not aggravate over the 12 months of the study. There was no observable change in non-frontal function. Emotional reactivity did not differ significantly between ALS patients and controls. CONCLUSIONS: This study provides further evidence for a mild defect in frontal cognitive processing in ALS patients that evolves only slowly, if at all, with time.