Modifying Neuropsychiatric and Motor Trajectories in Huntington's Disease Through an Integrated Neurobehavioral Clinic Model.

INTRODUCTION: Huntington's disease (HD) is a progressive neurodegenerative disorder characterized by worsening motor dysfunction, cognitive decline, and psychiatric symptoms. Psychiatric symptoms in HD arise from progressive frontostriatal circuit dysfunction and often precede motor manifestations, contributing significantly to disability and functional decline. In the absence of disease-modifying therapies, clinical care focuses on symptom management and functional preservation.

METHODS: This was a retrospective pre-post chart review comparing longitudinal clinical outcomes before and after implementation of a multidisciplinary clinic model in HD patients (N = 56) using an observational study design. Differences were analyzed using paired-samples t-tests, with effect sizes reported as Cohen's d. Depressive and anxiety symptoms were measured using the Patient Health Questionnaire-9 (PHQ-9) and Generalized Anxiety Disorder-7 (GAD-7), respectively. Motor symptoms were assessed using the Unified Huntington's Disease Rating Scale (UHDRS) motor subscale. Cognitive symptoms were measured using the Montreal Cognitive Assessment (MoCA).

RESULTS: Anxiety and depression symptom trajectories showed increased stability after initiation of the multidisciplinary clinic (ds = -0.008 and 0.133, respectively) compared to worsening trajectories prior to initiation (ds = 0.309 and 0.366, respectively). About 64-67% of patients were responders post-clinic relative to only 33-43% pre-clinic. Motor symptom severity significantly decreased following integrated clinic model implementation (d = -0.341), representing deviation from the expected progressive trajectory of manifest HD. Cognitive performance remained stable across follow-up intervals.

DISCUSSION: Our findings suggest that multidisciplinary integrated care may favorably influence motor and psychiatric symptom trajectories in HD, supporting the value of a coordinated, team-based approach to managing this complex disorder. While observed effects were not particularly large, in the context of a progressive neurodegenerative condition, modest improvement or even stabilization in symptoms represents a clinically meaningful deviation from the expected course of decline. However, conclusions and generalizability are limited by the modest sample size and retrospective observational design.