Cognitive and behavioral follow-up of patients with amyotrophic lateral sclerosis type 8

Amyotrophic Lateral Sclerosis type 8 (ALS8) is a familial motor neuron disease caused by the VAPB p.P56S mutation. There is a lack of longitudinal studies to elucidate the cognitive and behavioral progression of this disease. We aimed to investigate the progression of cognitive performance and behavioral symptoms of ALS8 patients over time.

The cohort was composed of 23 ALS8 patients (12 men). They underwent neuropsychological assessments in two periods of time, ranging from 24 to 48 months (mean follow-up: 33 ± 10).

There was mild motor and functional decline during the follow-up. There were no significant differences between the first and the second evaluation on tests of verbal fluency, executive functions, episodic memory, and facial emotion recognition. There was a decline in the Language subdomain from the Addenbrooke's Cognitive Examination-revised. Behavioural measures indicated decreasing stereotypic behaviours. Anxiety and depression symptoms remained stable. No patient developed dementia.

Cognitive decline parallels motor degeneration in ALS8, with a slow pattern of progression.