Cognitive impairment in motor neuron disease with bulbar onset.
METHODS
Twenty-three patients with bulbar onset motor neuron disease/amyotrophic lateral sclerosis (MND/ALS) were clinically assessed. They subsequently underwent serial neuropsychological testing, event-related potentials (ERP) and SPECT studies. Cognitive impairment was defined by clinical evidence of dementia (DSM-IV and frontal evaluation) or by significant alteration indicated by neuropsychological testing (excluding patients with depression and major anxiety), or both.


RESULTS
Eleven patients (48%) were found to be cognitively impaired. Abnormalities indicated fronto-temporal involvement, with memory impairment, alteration of judgement and reasoning, reduced speech, behavioural dyscontrol and alteration of daily living activities. This impairment correlated well with event-related potentials and SPECT studies. Event-related potentials were the most sensitive test as 100% of the impaired patients had abnormal ERP (p = 0.04). The cognitively impaired group differed from the other group mainly by gender ratio (male/female) with an important male predominance: 1.75 vs. 0.33. MND/ALS was also more severe when cognitive decline was present.


CONCLUSIONS
This study adds further arguments for a cognitive impairment in MND/ALS. This also reinforces the hypothesis that there is continuum between MND/ALS and fronto-temporal lobe dementia.
Portet
F
F
Unité de Neurologie Comportementale et dégénérativel, Hĵpital Gui de Chauliac, Montpellier, France. Floportet@aol.com
Cadilhac
C
C
Touchon
J
J
Camu
W
W
D000203:Activities of Daily Living / Q000523:psychology; D000328:Adult; D000368:Aged; D003704:Dementia / Q000175:diagnosis* / Q000503:physiopathology / Q000523:psychology; D005071:Evoked Potentials / Q000502:physiology; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D016472:Motor Neuron Disease / Q000175:diagnosis* / Q000503:physiopathology / Q000523:psychology; D009483:Neuropsychological Tests; D011379:Prognosis; D012737:Sex Factors; D013702:Temporal Lobe / Q000503:physiopathology; D014055:Tomography, Emission-Computed