The Many Facets of Unawareness in Huntington Disease

BACKGROUND: Unawareness or diminished awareness is present when a patient's perception of obvious disease manifestations and impact differ from that of observers such as clinicians or family members. METHODS: We examined studies that specifically investigate unawareness in Huntington disease (HD). RESULTS: Unawareness of motor, cognitive, behavioral, and functional aspects of HD has been documented throughout the disease course. This can occur at motor and cognitive onset but is more pronounced as the disease progresses. DISCUSSION: We discuss the implications for diagnosis, symptom report at presentation, timing of diagnosis, acceptance of symptomatic care strategies, and reporting in clinical trials. Assessments of work place competency, discrimination, driving, and the particular challenges of isolated patients without caregivers are described. Engaging with a person who is unaware of their disease or its impact presents a number of conflicts, including maintaining the right to autonomy, privacy, confidentiality, and independence while recognizing concerns for the wellbeing of the vulnerable person with HD and their caregiver when the unaware person refuses assistance. Unawareness is seen increasingly as neurologically based due to the impairment of functional networks, predominantly in nondominant frontostriatal pathways.