Sensitivity and specificity of the ECAS in identifying executive function and social cognition deficits in MND

Abstract

Objective: Motor neurone disease [MND] encompasses broad cognitive impairments, which are not fully captured by most screening tools. This study evaluated the specificity and sensitivity of the Edinburgh Cognitive and Behavioral ALS Screen [ECAS] in detecting impairments in executive function and social cognition. Methods: Participants (MND = 64; Healthy Controls = 45) completed the ECAS and standard neuropsychology tests of executive function and social cognition. Sensitivity and specificity of the ECAS were assessed at three levels (ALS-Specific score, executive function domain score, individual subtests: social cognition, inhibition, working memory, alternation). Results: MND patients were impaired on standard social cognition, initiation, visuomotor alternation, and verbal learning tests but not on inhibition or working memory tests, relative to controls. ECAS results revealed that the ALS-Specific score was high in specificity but low-to-moderately sensitive in identifying social cognition, inhibition, and working memory deficits, and that both sensitivity and specificity were high for identifying alternation deficits. The ECAS executive function domain score was high in specificity but poor in sensitivity for all four executive function domain subtests. The individual ECAS subtests were highly specific with good sensitivity, but the social cognition subtest lacked sensitivity. Conclusions: Impairments in social cognition may go undetected when using the ECAS as a screening tool. Thus, social cognition may need to be considered as a standalone component, distinct from the other executive functions. In addition, the test itself may need to be adjusted to encompass other aspects of social cognition that are affected in MND.

Key messages

• Cognitive screening tools are key to detect cognitive changes in MND, with the domains most affected being executive functions, language, and social cognition.

• The ECAS measure, developed for MND, has good specificity but lacks sensitivity to impairments in social cognition.

• Clinical implications are that cognitive impairments in social cognition may not be identified in MND patients by the ECAS.

• Adjustment to the ECAS cognitive screening tool widely-used in MND is suggested.

Key words:

• Motor neurone disease
• social cognition
• inhibition
• screening tool

Acknowledgements

We wish to thank all participants for their time, especially MND patients and their families.

Declaration of interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.

Notes

1 The Stroop Test consists of two sections. First, participants read aloud a list of colour words (tan, red, blue, green). The Stroop Colour Naming score reflects the number achieved in 2 min. Second, the words are then presented in an incongruent ink colour (e.g. “blue” printed in red ink) and participants name the colour of the ink. The Stroop Interference score reflects the number named in 2 minutes and Stroop Errors reflects the number of inhibition errors. The Stroop Difference score is calculated as the proportional difference between second interference section minus the first reading section (as detailed in Martin et al. (41,42)).

Additional information

Funding

This work was supported by an Australian National Health and Medical Research Council (NHMRC) Boosting Dementia Research Leadership Fellowship (APP1135769) awarded to GR, and the Brazil Family Program for Neurology.