A preliminary comparison between ECAS and ALS-CBS in classifying cognitive-behavioural phenotypes in a cohort of non-demented amyotrophic lateral sclerosis patients

To define the presence and type of frontotemporal dysfunction in amyotrophic lateral sclerosis (ALS), different screening tools have been created. Currently, the most used screening tests are the Edinburgh cognitive and behavioural ALS screen (ECAS) and the ALS cognitive behavioural screen (ALS-CBS). The objective of this study was to compare the ability of ECAS and ALS-CBS in classifying non-demented ALS patients according to Strong criteria. One-hundred and fifty-four in- and out-patients with an age > 18 and a definite or probable ALS diagnosis were recruited between September 2019 and February 2020 at NeMO Clinical Centre and at Istituto Auxologico Italiano in Milan and underwent the Edinburgh Cognitive and Behavioural ALS Screen (ECAS) and the ALS Cognitive Behavioural Screen (ALS-CBS). Exclusion criteria involved patients with a diagnosis of FTD, with a severe cognitive deterioration and/or an important behavioural impairment, with a significant psychiatric disorder or with the co-presence of another significant illness. The distribution of patients according to Strong criteria was different for ECAS and ALS-CBS and the degree of agreement between the two tests in terms of Cohen's Kappa coefficient resulted equal to 0.2047 with a 95% confidence limits interval between 0.1122 and 0.2973. This study for the first time compares the ability of ECAS and ALS-CBS in stratifying ALS patients. Further studies will be conducted to better understand the reasons underlying the differences between these two tests in classifying the different subtypes of fronto-temporal dysfunction in ALS.