The Impact of Family History on the Clinical Features of Huntington’s Disease

Clinical and Genetic Characteristics Associated With Survival Outcome in Late-Onset Huntington's Disease in South Korea

BACKGROUND AND PURPOSE

The onset of Huntington's disease (HD) usually occurs before the age of 50 years, and the median survival time from onset is 15 years. We investigated survival in patients with late-onset HD (LoHD) (age at onset ≥60 years) and the associations of the number of mutant CAG repeats and age at onset (AAO) with survival in patients with HD.

METHODS

Patients with genetically confirmed HD at six referral centers in South Korea between 2000 and 2020 were analyzed retrospectively. Baseline demographic, clinical, and genetic characteristics and the survival status as at December 2020 were collected.

RESULTS

Eighty-seven patients were included, comprising 26 with LoHD (AAO=68.77±5.91 years, mean±standard deviation; 40.54±1.53 mutant CAG repeats) and 61 with common-onset HD (CoHD) (AAO=44.12±8.61 years, 44.72±4.27 mutant CAG repeats). The ages at death were 77.78±7.46 and 53.72±10.86 years in patients with LoHD and CoHD, respectively (p<0.001). The estimated survival time was 15.21±2.49 years for all HD patients, and 10.74±1.95 and 16.15±2.82 years in patients with LoHD and CoHD, respectively. More mutant CAG repeats and higher AAO were associated with shorter survival (hazard ratio [HR]=1.05, 95% confidence interval [CI]=1.01-1.09, p=0.019; and HR=1.17, 95% CI=1.03-1.31, p=0.013; respectively) for all HD patients. The LoHD group showed no significant factors associated with survival after disease onset, whereas the number of mutant CAG repeats had a significant effect (HR=1.12, 95% CI=1.01-1.23, p=0.034) in the CoHD group.

CONCLUSIONS

Survival after disease onset was shorter in patients with LoHD than in those with CoHD. More mutant CAG repeats and higher AAO were associated with shorter survival in patients with HD.

'A medical case history … ': Huntington's disease and psychiatry

An important insight arising from the work of Michel Foucault is greater attention to the ways medical science produces subjects. In the case of Huntington's disease, the subjectivity produced has historically been constructed as dysfunctional and threatening, while the subjectivity of the researcher was unscrutinised. This paper describes a Foucauldian analysis of 20th century medical and social scientific literature on the social consequences of Huntington's disease. It identifies three features of Huntington's disease as central to its discursive construction: its genetic transmission pattern, its age of onset and its behavioural symptoms. These qualities, converted into medical and psychiatric knowledge, facilitated the absorption of Huntington's disease into eugenicist discourse, a connection reflected throughout the literature. Through various techniques of power, especially genetic pedigrees, and the normalised appropriation and exploitation of patients' identities and data within psychiatry, affected individuals were subjectified as contaminated and threatening, and implicated in the intergenerational transmission of social dysfunction.

Using a Clinical Formulation to Understand Psychological Distress in People Affected by Huntington’s Disease: A Descriptive, Evidence-Based Model

Huntington’s disease (HD) is an inherited, life-limiting neurodegenerative condition. People with HD experience changes in cognitive, motor and emotional functioning, and can also, mainly at later stages, exhibit behaviours that professionals and carers might find distressing such as hitting others, throwing objects, swearing or making inappropriate comments. While clinical formulation (an individualised approach used by mental health professionals to describe an individual’s difficulties) is a helpful tool to conceptualise patients’ wellbeing, a specific formulation framework has not yet been developed for HD. However, evidence has shown that formulation can help guide clinical interventions and increase consistency of approach across multi-disciplinary teams, refine risk management, and improve staff or carers’ empathic skills and understanding of complex presentations. As a consequence, this paper proposes a new clinical formulation model for understanding distress among people with HD, based on a biopsychosocial framework. More specifically, this includes key elements centring on an individual’s past experience and personal narratives, as well as anticipatory cognitions and emotions about the future. In-depth discussions regarding the components of the model and their importance in HD formulations are included, and a fictional yet representative case example is presented to illustrate their application within the context of personalised care.

Another Perspective on Huntington's Disease: Disease Burden in Family Members and Pre-Manifest HD When Compared to Genotype-Negative Participants from ENROLL-HD

Background: In addition to the effects on patients suffering from motor-manifest Huntington’s disease (HD), this fatal disease is devasting to people who are at risk, premanifest mutation-carriers, and especially to whole families. There is a huge burden on people in the environment of affected HD patients, and a need for further research to identify at-risk caregivers. The aim of our research was to investigate a large cohort of family members, in comparison with genotype negative and premanifest HD in order to evaluate particular cohorts more closely. Methods: We used the ENROLL-HD global registry study to compare motoric, cognitive, functional, and psychiatric manifestation in family members, premanifest HD, and genotype negative participant as controls. Cross-sectional data were analyzed using ANCOVA-analyses in IBM SPSS Statistics V.28. Results: Of N = 21,116 participants from the global registry study, n = 5174 participants had a premanifest motor-phenotype, n = 2358 were identified as family controls, and n = 2640 with a negative HD genotype. Analysis of variance revealed more motoric, cognitive, and psychiatric impairments in premanifest HD (all p < 0.001). Self-reported psychiatric assessments revealed a significantly higher score for depression in family controls (p < 0.001) when compared to genotype negative (p < 0.001) and premanifest HD patients (p < 0.05). Family controls had significantly less cognitive capacities within the cognitive test battery when compared to genotype negative participants. Conclusions: Within the largest cohort of HD patients and families, several impairments of motoric, functional, cognitive, and psychiatric components can be confirmed in a large cohort of premanifest HD, potentially due to prodromal HD pathology. HD family controls suffered from higher self-reported depression and less cognitive capacities, which were potentially due to loaded or stressful situations. This research aims to sensitize investigators to be aware of caregiver burdens caused by HD and encourage support with socio-medical care and targeted psychological interventions. In particular, further surveys and variables are necessary in order to implement them within the database so as to identify at-risk caregivers.

Differential Diagnosis of Chorea-HIV Infection Delays Diagnosis of Huntington's Disease by Years

Background: There is a broad range of potential differential diagnoses for chorea. Besides rare, inherited neurodegenerative diseases such as Huntington’s disease (HD) chorea can accompany basal ganglia disorders due to vasculitis or infections, e.g., with the human immunodeficiency virus (HIV). The clinical picture is complicated by the rare occurrence of HIV infection and HD. Methods: First, we present a case suffering simultaneously from HIV and HD (HIV/HD) focusing on clinical manifestation and disease onset. We investigated cross-sectional data regarding molecular genetic, motoric, cognitive, functional, and psychiatric disease manifestation of HIV/HD in comparison to motor-manifest HD patients without HIV infection (nonHIV/HD) in the largest cohort of HD patients worldwide using the registry study ENROLL-HD. Data were analyzed using ANCOVA analyses controlling for covariates of age and CAG repeat length between groups in IBM SPSS Statistics V.25. Results: The HD diagnosis in our case report was delayed by approximately nine years due to the false assumption that the HIV infection might have been the cause of chorea. Out of n = 21,116 participants in ENROLL-HD, we identified n = 10,125 motor-manifest HD patients. n = 23 male participants were classified as suffering from HIV infection as a comorbidity, compared to n = 4898 male non-HIV/HD patients. Except for age, with HIV/HD being significantly younger (p < 0.050), we observed no group differences regarding sociodemographic, genetic, educational, motoric, functional, and cognitive parameters. Male HIV/HD patients reported about a 5.3-year-earlier onset of HD symptoms noticed by themselves compared to non-HIV/HD (p < 0.050). Moreover, patients in the HIV/HD group had a longer diagnostic delay of 1.8 years between onset of symptoms and HD diagnosis and a longer time regarding assessment of first symptoms by the rater and judgement of the patient (all p < 0.050). Unexpectedly, HIV/HD patients showed less irritability in the Hospital Anxiety and Depression Scale (all p < 0.05). Conclusions: The HD diagnosis in HIV-infected male patients is secured with a diagnostic delay between first symptoms noticed by the patient and final diagnosis. Treating physicians therefore should be sensitized to think of potential alternative diagnoses in HIV-infected patients also afflicted by movement disorders, especially if there is evidence of subcortical atrophy and a history of hyperkinesia, even without a clear HD-family history. Those patients should be transferred for early genetic testing to avoid further unnecessary diagnostics and improve sociomedical care.

Age of onset and behavioral manifestations in Huntington's disease: An Enroll-HD cohort analysis

Huntington's disease is associated with motor, cognitive and behavioral dysfunction. Behavioral symptoms may present before, after, or simultaneously with clinical disease manifestation. The relationship between age of onset and behavioral symptom presentation and severity was explored using the Enroll-HD database. Manifest individuals (n = 4469) were initially divided into three groups for preliminary analysis: early onset (<30 years; n = 479); mid-adult onset (30-59 years; n = 3478); and late onset (>59 years; n = 512). Incidence of behavioral symptoms reported at onset was highest in those with early onset symptoms at 26% (n = 126), compared with 19% (n = 678) for mid-adult onset and 11% (n = 56) for late onset (P < 0.0001). Refined analysis, looking across the continuum of ages rather than between categorical subgroups found that a one-year increase in age of onset was associated with a 5.6% decrease in the odds of behavioral symptoms being retrospectively reported as the presenting symptom (P < 0.0001). By the time of study enrollment, the odds of reporting severe behavioral symptoms decreased by 5.5% for each one-year increase in reported age of onset. Exploring environmental, genetic and epigenetic factors that affect age of onset and further characterizing types and severity of behavioral symptoms may improve treatment and understanding of Huntington's disease's impact on affected individuals.

Influence of Age of Onset on Huntington's Disease Phenotype

Background

Older patients with Huntington's disease (HD) are often thought to have a slower progressing disease course with less behavioral symptoms than younger patients. However, phenotypic differences based on age of onset have not been well characterized in a large HD population. This study will determine the difference in manifestations and disease progression between patients with young, typical, and late onset adult HD at different stages of disease.

Methods

Data obtained from Enroll-HD. Adults with manifest HD were included. Age groups were defined as young onset (YO: 20-29 years), typical onset (TO: 30-59 years), and late onset (LO: 60+ years). Subjects were categorized by TFC score, from Stage I (least severe) to Stage V (most severe). Motor, cognitive, and behavioral symptoms were analyzed. Descriptive statistics and Bonferroni p-value correction for pairwise comparison were calculated.

Results

7,311 manifest HD participants were included (612 YO, 5,776 TO, and 923 LO). The average decline in TFC score from baseline to second visit (1.5-2.5 years) was significantly faster for YO (-1.75 points) compared to TO (-1.23 points, p = 0.0105) or LO (-0.97 points, p = 0.0017). Motor deficits were worse for LO participants at early stages of HD, and worse for YO participants at advanced stages. YO and TO participants had greater burden of behavioral symptoms at early stages of disease compared to LO.

Discussion

YO is predictive of a faster functional decline for adults with HD when compared to those with TO and LO. Motor and behavioral manifestations differ based on age of onset.

Highlights

This study compares HD manifestations while controlling for disease severity, detailing robust phenotypic differences by age of onset alone. These findings have implications for the clinical management of HD symptoms and have the possibility to improve prognostic and treatment precision.

Awareness of genetic risk in the Dominantly Inherited Alzheimer Network (DIAN)

INTRODUCTION

Although some members of families with autosomal dominant Alzheimer's disease mutations learn their mutation status, most do not. How knowledge of mutation status affects clinical disease progression is unknown. This study quantifies the influence of mutation awareness on clinical symptoms, cognition, and biomarkers.

METHODS

Mutation carriers and non-carriers from the Dominantly Inherited Alzheimer Network (DIAN) were stratified based on knowledge of mutation status. Rates of change on standard clinical, cognitive, and neuroimaging outcomes were examined.

RESULTS

Mutation knowledge had no associations with cognitive decline, clinical progression, amyloid deposition, hippocampal volume, or depression in either carriers or non-carriers. Carriers who learned their status mid-study had slightly higher levels of depression and lower cognitive scores.

DISCUSSION

Knowledge of mutation status does not affect rates of change on any measured outcome. Learning of status mid-study may confer short-term changes in cognitive functioning, or changes in cognition may influence the determination of mutation status.