A screening assessment of cognitive impairment in patients with ALS

We wished to determine whether a screening test battery for cognitive impairment can be given practicably in a busy multidisciplinary ALS clinic, and to assess initial test performance in a sequentially drawn ALS population. We administered a word generation task (letter fluency), the Frontal Behavioral Inventory (FBI), and the Beck Depression Inventory (BDI) to 49 ALS patients and their caregivers during a visit to our ALS clinic. We also computed Clinical Dementia Rating (CDR) scale and ALS Functional Rating Scale (ALSFRS- R) scores for patients. Pearson correlation coefficients and regression analyses assessed associations between outcome measures. The test battery took 30 min to administer. Word generation was associated with the FBI score (r=-0.36, p=0.01), and time to ALS diagnosis (p=0.01). Caregiver depressive symptoms (BDI) correlated with the FBI (r=0.40, p=0.005) and motor severity (r=-0.47, p<0.01) in patients. CDR scores were associated with behavioral abnormalities and lower ALSFRS- R scores. We concluded that a screen of cognition could be administered during multidisciplinary ALS clinics. Frontostriatal cognitive impairment may be associated with behavioral syndromes and more rapid forms of ALS. Behavioral and motor impairment is associated with depressive symptoms in caregivers. Studies with formal neuropsychological tests are needed to determine the sensitivity and specificity of the screen in ALS.