What is the extent of reliability and validity evidence for screening tools for cognitive and behavioural change in people with ALS? A systematic review

Objective: This systematic review provides an updated summary of the existing literature on the validity of screening tools for cognitive and behavioural impairment in people with Amyotrophic Lateral Sclerosis (pwALS), and also focuses on their reliability. Method: The following cognitive and behavioural screening tools were assessed in this review: the Edinburgh Cognitive and Behavioural ALS Screen (ECAS); the ALS Cognitive Behavioural Screen (ALS-CBS), the Mini Addenbrooke’s Cognitive Examination (Mini-ACE), the Beaumont Behavioural Interview (BBI); the MND Behaviour Scale (MiND-B); and the ALS-FTD Questionnaire (ALS-FTD-Q). A search, using Medline, PsychINFO and Embase (21/09/2023), generated 37 results after exclusion criteria were applied. Evidence of internal consistency, item-total correlations, inter-rater reliability, clinical validity, convergent validity, and structural validity were extracted and assessed and risk of bias was evaluated. Results: The cognitive component of the ECAS was the tool with most evidence of reliability and validity for the assessment of cognitive impairment in ALS. It is well-suited to accommodate physical symptoms of ALS. For behavioural assessment, the BBI or ALS-FTD-Q had the most evidence of reliability and validity. The BBI is more thorough, but the ALS-FTD-Q is briefer. Conclusions: There is good but limited evidence for the reliability and validity of cognitive and behavioural screens. Further evidence of clinical and convergent validity would increase confidence in their clinical and research use. <br/

Does genetic anticipation occur in familial Alexander disease?

Alexander Disease (AxD) is a rare leukodystrophy caused by missense mutations of glial fibrillary acidic protein (GFAP). Primarily seen in infants and juveniles, it can present in adulthood. We report a family with inherited AxD in which the mother presented with symptoms many years after her daughter. We reviewed the age of onset in all published cases of familial AxD and found that 32 of 34 instances of parent–offspring pairs demonstrated an earlier age of onset in offspring compared to the parent. We suggest that genetic anticipation occurs in familial AxD and speculate that genetic mosaicism could explain this phenomenon