Frontal-lobe mediated behavioral dysfunction in amyotrophic lateral sclerosis.
BACKGROUND
Cognitive impairment secondary to frontal lobe atrophy exists in 40-60% of Amyotrophic Lateral Sclerosis (ALS) cases. We aimed to determine the prevalence of frontal-lobe mediated behavioral impairment in (ALS) and to ascertain its relationship to cognitive impairment.


METHODS
Two-hundred and twenty five patients diagnosed with sporadic ALS were evaluated for behavioral dysfunction using the Frontal Systems Behavior Scale (FrSBe), a validated measure used to examine frontal-lobe mediated behaviors, specifically apathy, executive dysfunction and disinhibition; a total behavior score is also provided. Additionally, a subset of patients also underwent a comprehensive neuropsychological evaluation.


RESULTS
Changes in the total FrSBe scores were observed in 24.4% of the patients and 39.6% of the patients had impairment in at least one behavioral domain with symptoms of Apathy being the most common (31.1%). Cognitively impaired ALS patients had worse total (P = 0.05) and apathy scores (P < 0.01); however, behavioral dysfunction was also present in 16% of the cognitively intact patients. Half of the behaviorally intact patients exhibited cognitive impairment. Significant correlations were observed for performance on certain neuropsychological tests (Animal fluency, Block Design, Logical Memory I and Verbal Series Attention Test) and severity of behavioral dysfunction on certain FrSBe sub scores.


CONCLUSIONS
Frontal-lobe mediated behavioral dysfunction appears to be common in ALS. Cognitively impaired ALS patients had greater behavioral dysfunction. Recognition of behavioral and cognitive dysfunction may assist health-care providers and care-givers recognize changes in decision-making capacity and treatment compliance of patients with ALS.
Witgert
M
M
Department of Neurology, Baylor College of Medicine, Houston, TX 77030, USA.
Salamone
A R
AR
Strutt
A M
AM
Jawaid
A
A
Massman
P J
PJ
Bradshaw
M
M
Mosnik
D
D
Appel
S H
SH
Schulz
P E
PE
D000328:Adult; D000368:Aged; D000690:Amyotrophic Lateral Sclerosis / Q000453:epidemiology* / Q000523:psychology*; D003072:Cognition Disorders / Q000175:diagnosis* / Q000453:epidemiology*; D015897:Comorbidity; D003657:Decision Making / Q000502:physiology; D004185:Disability Evaluation; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology*; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000175:diagnosis / Q000453:epidemiology; D008875:Middle Aged; D009483:Neuropsychological Tests; D011237:Predictive Value of Tests; D015995:Prevalence; D012720:Severity of Illness Index