Self-awareness of motor dysfunction in patients with Huntington's disease in comparison to Parkinson's disease and cervical dystonia

Abstract

Individuals suffering from Huntington's disease (HD) have been shown to present with poor self-awareness of a variety of symptoms. The aim of this study was to better assess the self-awareness of motor symptoms and activities of daily living (ADL) impairment in HD, in comparison to Parkinson's disease (PD) and cervical dystonia (CD). In particular, the anosognosia/anosodiaphoria of involuntary movements has been investigated. Self-awareness was tested in 23 patients with HD by comparing patient and caregiver ratings in reference to clinical control groups (25 PD with dyskinesias, PDdys; 21 PD without dyskinesias, PDndys; and 20 with CD). Patients were assessed neurologically by relevant rating scales. Self-awareness was tested using a scale based on 15 films demonstrating 3 types of motor symptoms (chorea/dyskinesias, parkinsonism, torticollis) as well as the Self-Assessment Parkinson's Disease Disability Scale. General cognitive status, verbal learning, cognitive control, and mood were also analyzed. Our results indicate that self-awareness of choreic movements was affected more severely in HD than in PDdys, despite comparable cognitive status. Patient-proxy agreement on ADL impairment was roughly similar in all clinical groups. The results are discussed in the context of orbitofrontal-limbic pathology as a potential trigger of anosognosia/anosodiaphoria in individuals with HD.