Apathy in amyotrophic lateral sclerosis: insights from Dimensional Apathy Scale

Abstract

Objectives: Apathy is associated with cognitive decline and worse survival in amyotrophic lateral sclerosis (ALS); an accurate evaluation of this aspect is relevant in clinical settings. The aims of this study are to evaluate the prevalence of apathy in a large ALS sample, using published diagnostic criteria, and to explore the psychometric properties, the sensitivity and the specificity of the Dimensional Apathy Scale (DAS) as a screening tool for apathy.

Methods: One hundred and thirty-one patients underwent clinical interview based on diagnostic criteria for apathy, DAS, Apathy Evaluation Scale, and assessment of depression, global cognitive functioning, and non-verbal intelligence.

Results: According to diagnostic criteria, apathy occurred in 28.2% of the patients. The DAS showed high consistency, convergent, and discriminant validities. Apathetic and non-apathetic patients significantly differed on total DAS and executive and Behavioral/Cognitive Initiation subscales, indicating good criterion validity. Receiver operating characteristics analysis, considering diagnostic criteria for apathy as gold standard, revealed that a score of 26/27 was an optimal cut-off score for the identification of apathy.

Conclusions: The DAS is a valid screening tool for apathy and its aspects in ALS through limiting the impact of physical disability. Executive and behavioral/cognitive aspects of apathy, rather than emotional aspects, are more frequent in ALS.

Keywords:

• Apathy
• dimensional apathy scale
• amyotrophic lateral sclerosis
• DAS
• ALS
• non motor symptoms

Acknowledgements

The authors thank Dr Manuela Santoro and Dr Roberta Greco for their contribution in collecting data.

Disclosure of interest

The authors report no conflicts of interest.

Supplemental data available online