Improving the Clinical Diagnostic Criteria for Genetically Confirmed Adult-Onset Huntington Disease: Considering Nonmotor Presentations.

Background: Huntington disease (HD) is a genetic neurodegenerative disorder. Given the focus on motor manifestations, nonmotor symptoms are frequently underappreciated in clinical evaluations, despite frequently contributing to primary functional impairment.

Recent findings: A diagnosis of motor-onset as the definition of manifest symptoms misrepresents the complex nature of HD presentation. Despite recent attempt to integrate nonmotor diagnostic criteria, practical guidelines are necessary to inform clinical diagnosis. We propose an HD diagnostic framework and staging system that prioritizes genetic testing, integrates motor and nonmotor symptom considerations in the determination of clinical disease onset and severity, and acknowledges the secondary role of clinically indicated diagnostic assessments, incorporating the broad symptom profiles observed in clinical practice.

Implications for practice: The proposed diagnostic criteria more accurately reflect the presentation of HD and provide greater opportunities for health care professionals to provide appropriate clinical care guidelines for adults with gene-expanded HD.