Mood disorders in patients with motor neuron disease and frontotemporal symptoms: Validation of the Hospital Anxiety and Depression Scale for use in motor neuron disease

Background: Motor neuron disease (MND) is a heterogeneous neurodegenerative disorder, with nearly 50 % of patients exhibiting cognitive and behavioral symptoms in addition to motor decline. Anxiety and depression, though frequently observed in this population, have been understudied in relation to motor and extra-motor profiles. Objectives: Our study addresses this gap by validating the Hospital Anxiety and Depression Scale for Motor Neuron Disease (HADS-MND) and investigating the interplay between mood, clincial, and frontotemporal symptoms in a large sample of MND patients. Methods: A total of 249 MND patients underwent clinical, genetic, and neuropsychological assessments. The validity, reliability, sensitivity, and specificity of the HADS-MND global score and subscores were explored. Correlation analyses and group comparisons tested the link between mood, motor and extra-motor profiles. Results: The bidirectional structure of the HADS-MND was confirmed, but receiver operating characteristics analysis suggests caution for clinical use of the anxiety and depression subscales. The global HADS-MND score is recommended as a measure of psychological distress, with a cut-off point of 10 detecting 38 % of patients with altered scores. Moderate symptoms of anxiety and depression were present in 14 % and 11 % of cases, respectively. Depressive mood was higher in women, patients with frontotemporal symptoms, and severe motor-functional disabilities. Depressive and/or anxiety symptoms were linked to loneliness, behavioral changes, emotional dysregulation, and poor quality of life. Cognitive efficiency was not associated with mood. Conclusion: Mood disorders appeared independent of cognitive profiles but related to behavioral changes. This is particularly relevant for clinicians discussing end-of-life decisions with patients.