Anosognosia Is Associated With Greater Caregiver Burden and Poorer Executive Function in Huntington Disease

Huntington study group's neuropsychology working group position on best practice recommendations for the clinical neuropsychological evaluation of patients with Huntington disease

Objective: Neuropsychological evaluation is critical to detection and management of cognitive and neuropsychiatric changes associated with Huntington disease (HD). Accurate assessment of non-motor complications of HD is critical given the prominent impact on functional disability, frequently commensurate with or exceeding that of motor symptoms. The increasing emphasis on developing disease-modifying therapies targeting cognitive decline in HD requires consensus on clinical neuropsychological assessment methods. The Neuropsychology Working Group (NPWG) of the Huntington Study Group (HSG) sought to provide evidence and consensus-based, practical guidelines for the evaluation of cognitive and neuropsychiatric symptoms associated with HD. Method: The NPWG recruited a multi-disciplinary group of neuropsychologists, neurologists, and psychiatrists to inform best practices in assessing, diagnosing, and treating the non-motor symptoms in HD. A review was circulated among the NPWG, and in an iterative process informed by reviewed literature, best practices in neuropsychological evaluation of patients with HD were identified. Results: A brief review of the available literature and rational for a clinical consensus battery is offered. Conclusion: Clinical neuropsychologists are uniquely positioned to both detect and characterize the non-motor symptoms in HD, and further, provide neurologists and allied health professions with clinically meaningful information that impacts functional outcomes and quality of life. The NPWG provides guidance on best practices to clinical neuropsychologists in this statement. A companion paper operationalizing clinical application of previous research-based non-motor diagnostic criteria for HD is forthcoming, which also advises on non-motor symptom screening methods for the non-neuropsychologist working with HD.

Influence of anosognosia on patient-reported outcomes for psychiatric symptoms and quality of life in Huntington's disease

INTRODUCTION

Anosognosia, defined as reduced awareness of one's deficit or symptom, is common in Huntington's disease (HD) and detectable at each disease stage. The impact of anosognosia on self-reporting in HD populations is critical to understand given growing use of patient-reported outcomes in HD clinical care and research. We aimed to determine the influence of anosognosia on patient-reported outcome measures assessing psychiatric symptoms and quality of life in HD.

METHODS

We enrolled HD patients to complete a battery of patient-reported and rater-administered measures, including the Anosognosia Scale, at baseline and 6 months later. Patient-reported outcome measures included NeuroQoL short forms for depression, anxiety, satisfaction with social roles and activities, and positive affect and well-being and Patient-Reported Outcomes Measurement Information System short forms for emotional distress-anger and sleep-related impairment. Anosognosia Scale-Difference Score indexed patient-clinician agreement on patient motor, cognitive, and behavioral abilities. We conducted multivariable linear regression analyses to quantify the association of baseline anosognosia with 6-month patient-reported outcomes.

RESULTS

Of 79 patients with complete Anosognosia Scale data at baseline, 25 (31.6 %) met the scale's criterion for anosognosia. In the regression analyses, baseline Difference Score improved prediction of 6-month patient-reported outcomes for depression, anxiety, anger, and positive affect and well-being (χ2(1) value range for likelihood ratio tests contrasting models with and without Difference Score: 13.1-20.9, p-values <0.001). Patients with more anosognosia self-reported less severe psychiatric symptoms and more positive affect and well-being.

CONCLUSION

Study results suggest that anosognosia influences patient-reported outcomes for psychiatric symptoms and quality of life in HD populations.

Facilitators and barriers in caring for a person with Huntington's disease: input for a remote support program

OBJECTIVES

This study aims to provide more insight into possible barriers and facilitators caregivers of people with Huntington's disease (HD) encounter, and what their needs and wishes are regarding a remote support program.

METHODS

In total, 27 persons participated in four focus group interviews. Eligible participants were caregivers (n = 19) of a person with HD, and healthcare professionals (n = 8) involved in HD care. Qualitative data were analyzed by two researchers who independently performed an inductive content analysis.

RESULTS

Four major themes emerged from the data, including (1) a paradox between taking care of yourself and caring for others; (2) challenges HD caregivers face in daily life, including lack of HD awareness, taboo and shame, feelings of loneliness, concerns about heredity and children, and coping with HD symptoms; (3) facilitators in the caregiving process, including a social network, professional support, openness, talking in early phases, and daily structure; (4) needs regarding a support program.

CONCLUSION

These insights will be used to develop a remote support program for HD caregivers, using a blended and self-management approach. Newly developed and tailored support should be aimed at empowering caregivers in their role and help them cope with their situation, taking into account barriers and facilitators.

Caregiver Burden of Patients With Huntington's Disease in South Korea

OBJECTIVE

This is the first prospective cohort study of Huntington's disease (HD) in Korea. This study aimed to investigate the caregiver burden in relation to the characteristics of patients and caregivers.

METHODS

From August 2020 to February 2022, we enrolled patients with HD from 13 university hospitals in Korea. We used the 12-item Zarit Burden Interview (ZBI-12) to evaluate the caregiver burden. We evaluated the clinical associations of the ZBI-12 scores by linear regression analysis and investigated the differences between the low- and high-burden groups.

RESULTS

Sixty-five patients with HD and 45 caregivers were enrolled in this cohort study. The average age at onset of motor symptoms was 49.3 ± 12.3 years, with an average cytosine-adenine-guanine (CAG)n of 42.9 ± 4.0 (38-65). The median ZBI-12 score among our caregivers was 17.6 ± 14.2. A higher caregiver burden was associated with a more severe Shoulson-Fahn stage (p = 0.038) of the patients. A higher ZBI-12 score was also associated with lower independence scale (B = -0.154, p = 0.006) and functional capacity (B = -1.082, p = 0.002) scores of patients. The caregiving duration was longer in the high- than in the low-burden group. Caregivers' demographics, blood relation, and marital and social status did not affect the burden significantly.

CONCLUSION

HD patients' neurological status exerts an enormous impact on the caregiver burden regardless of the demographic or social status of the caregiver. This study emphasizes the need to establish an optimal support system for families dealing with HD in Korea. A future longitudinal analysis could help us understand how disease progression aggravates the caregiver burden throughout the entire disease course.

Prevalence of neurocognitive disorder in Huntington's disease using the Enroll-HD dataset

Background

Cognitive decline in Huntington's disease (HD) begins early in the disease course, however the reported prevalence and severity of cognitive impairment varies based on diagnostic approach. A Movement Disorders Society Task Force recently endorsed the use of standardized DSM-5-based criteria to diagnose neurocognitive disorder (NCD) in Huntington's disease.

Objectives

To determine the prevalence and severity of cognitive impairment across different stages of HD by applying NCD criteria (mild and major) to participant data from the Enroll-HD database.

Methods

Enroll-HD participants were triaged into either premanifest (preHD), manifest or control groups. PreHD was further dichotomized into preHD near or preHD far based on predicted time to diagnosis using the scaled CAG-age product score (CAPs). Embedded cognitive performance and functional independence measures were used to determine prevalence of NCD (mild and major) for all groups.

Results

Prevalence of NCD-mild was 25.2%-38.4% for manifest HD, 22.8%-47.3% for preHD near, 11.5%-25.1% for preHD far, and 8.8%-19.1% for controls. Prevalence of NCD-major was 21.1%-57.7% for manifest HD, 0.5%-16.3% for preHD near, 0.0%-4.5% for preHD far, and 0.0%-3.0% for controls.

Conclusion

The prevalence of NCD in HD is elevated in preHD and demonstrates a sharp rise prior to diagnosis. In manifest HD, the vast majority of participants meet criteria for NCD. These findings are important for optimizing clinical care and/or anticipating the need for supportive services.

"I don't have Huntington's disease": the boundaries between acceptance and understanding

Huntington's disease (HD) is an inherited disease that leads to an inexorable progression of motor, cognitive and psychiatric disturbances. In the initial stages, the symptoms are not clearly disabling, and the patient may present a lack of awareness about the symptoms themselves, which we call anosognosia. However, anosognosia might not justify all passivity of the HD patient in face of the diagnosis. Patients may also experience the denial of illness, as a stage of grief, expected to happen in the face of the diagnosis of any neurodegenerative disorder. In addition, people with HD tend to be more apathetic, and more silent, in regular consultations. In the present article, the authors express a point of view, discussing the behavior of the HD patient, in which there is a multifactorial passivity, in the face of the diagnosis and of the disease itself. Having the proper knowledge of this situation may prepare the neurologist to better understand the patient and the evolution of the disease.

Anosognosia in HD: Comparison of self-report and caregiver ratings with objective performance measures

INTRODUCTION

Individuals with Huntington's disease (HD) commonly experience anosognosia, a lack of awareness of deficits. Thus, it is important to examine the accuracy of patient vs caregiver ratings on the basis of objective performance-based measures.

METHODS

The Anosognosia Scale (AS) was given to 33 patients with manifest HD and their caregivers. The AS consists of 8 items in which individuals rate their global abilities relative to same-aged peers. Scores range from very impaired to excellent. Caregiver and patient ratings were then correlated with objective measures.

RESULTS

Caregivers' evaluations of patients' cognitive and motoric abilities were more highly correlated with objective measures than patients' ratings. Specifically, caregivers' AS item scores were highly correlated with objective measures of walking (Unified Huntington Disease Rating Scale (UHDRS) tandem walking score [r = 0.57, p = .001] vs. patient [r = 0.39, p = .031]); dexterity (UHDRS pronation supination score [r = 0.55, p = .011] vs. patient [r = 0.18, p = .393]); speech (UHDRS dysarthria score [r = 0.55, p = .004] vs. patient [r = 0.03, p = .854]); memory (MoCA score [r = -.45, p = .048] vs. patient [r = -.11, p = .963]); attention (Trails Making Test A score [r = 0.58, p = .004] vs. patient [r = 0.08, p = .686]); and word retrieval (category fluency ([r = -.58, p = .004] vs. patient [r = -.02, p = 1.00]). Moreover, both the UHDRS total motor score (TMS) (F(1,29) = 7.50, p = .010) and the Mini Mental Status Exam (MMSE) (F(1,31) = 5.40, p = .027) were significant predictors of patient levels of anosognosia.

CONCLUSIONS

Our findings indicate that caregivers may be better able to rate HD patients' cognitive and motor abilities than patients themselves. Both cognitive and motor severity are significant predictors of levels of anosognosia in HD.

Informal care in Huntington's disease: Assessment of objective-subjective burden and its associated risk and protective factors

BACKGROUND

Because of the genetic transmission of Huntington's disease (HD), informal caregivers (ICs, i.e., non-professional caregivers) might experience consecutive and/or concurrent caregiving roles to support several symptomatic relatives with HD over their life. Additionally, some ICs might be HD carriers. However, whether family burden of care is associated with specific factors in HD remains poorly studied.

OBJECTIVE

To provide a quantitative view of the IC burden and identify associated factors.

METHODS

This was a cross-sectional assessment of home-dwelling symptomatic HD individuals (from REGISTRY and Bio-HD studies) and their primary adult ICs, including the HD individual's motor, cognitive, behavioral, functional Unified Huntington's Disease Rating Scale score; IC objective burden (quantification of IC time in activities of daily living, instrumental activities of daily living and supervision, using the Resource Utilization in Dementia instrument), IC subjective burden (Zarit Burden Inventory), and ICs' social economic functioning and use of professional home care.

RESULTS

We included 80 ICs (mean [SD] age 57 [12.9] years, 60% women) in charge of 80 individuals with early to advanced stage HD (mean age 56 [12.6] years, 51% men). The mean hours of informal care time was high: 7.3 (7.9) h/day (range 0-24); the mean professional home care was 2.8 (2.8) h/day (range 0.1-12.3). This objective burden increased with higher functional loss of the HD individual and with more severe cognitive-behavioral disorders. The mean subjective burden (35.4 [17.8], range 4-73) showed a high level since the earliest stage of HD; it was associated with HD duration (mean 9.2 [4.7] years) and with aggressive symptoms in individuals (44% of cases). The burden was partially related to the multiplex caregiving status (19%). Protective factors lowering the IC burden included the absence of financial hardship (57%), a strong social network (16%) and keeping active on the job market outside home (46%).

CONCLUSIONS

The objective-subjective burden of ICs related to changing patterns of neuro-psychiatric symptoms and mitigating environmental characteristics around the HD individual-caregiver dyads.

Disease Burden of Huntington's Disease (HD) on People Living with HD and Care Partners in Canada

Background:

Huntington’s disease (HD) has been shown to reduce health-related quality of life (HRQoL) and affect healthcare resource utilization (HRU) among patients and care partners internationally but has not been studied specifically in the Canadian context.

Objective:

To characterize the burden of HD on individuals with HD and care partners of individuals with HD in Canada.

Methods:

An online survey was distributed (September 14–November 23, 2020) through patient organizations to collect data on demographic and clinical characteristics, as well as: HRQoL, measured using the 36-Item Short-Form Health Survey (SF-36v1); HRU, measured using the Client Service Receipt Inventory (CSRI); and care partner burden, measured using the Caregiver Strain Index (CSI) and Huntington’s Disease Quality of Life Battery for Carers (HDQoL-C). Descriptive statistics were used to report data and compare subgroups.

Results:

A total of 62 adult individuals with HD (or their proxies) and 48 care partners met defined eligibility criteria. The mean [standard deviation] age was 51.2 [13.8] and 58.1 [13.9] years for individuals with HD and care partner respondents, respectively. For individuals with HD, the greatest HRQoL burden (i.e., lowest score) was for the SF-36v1 Role –Physical scale (46.8 [42.9]). HRU was higher for some services (e.g., general practitioner visits) for respondents who had experienced motor onset transition. Among care partners, 55.3% experienced high strain, as indicated by the CSI. The HDQoL-C showed the greatest HRQoL burden in feelings about life (45.1 [17.9]).

Conclusion:

This study quantified the substantial burden on individuals with HD and care partners in Canada, addressing a critical knowledge gap that can affect the availability of and access to healthcare services.

Beyond the clinical context: the process of losing oneself living with Huntington's disease

BACKGROUND

People with Huntington's disease (HD) have increased functional and cognitive dependence. While numerous clinical, genetic, and therapeutic management studies have been carried out, few studies have investigated the disease from the personal experience and the context of people living with HD. To better serve these patients, our purpose is to understand, from the perspective of the patient and their families, how people with HD cope with their daily lives outside the clinical setting.

METHODS

Thirty-three affected or at-risk people participated in this study. Participants were interviewed at their homes on distinct occasions during a family visit. We analyzed the data using Grounded Theory, which allowed us to understand how people live with the disease on their own terms.

RESULTS

Living with HD is a process that begins with acceptance or denial that one is at risk for the disease or, growing awareness of the condition due to motor, behavioral, and cognitive changes, and, finally, loss of autonomy with physical dependence on another person, and loss of sense of self and family.

CONCLUSION

While the daily life of patients before disease onset was characterized by physical and mental/cognitive independence, with HD they become increasingly trapped in their bodies, and their complications are due to the lack of effective curable therapy.

Anosognosia and Memory Encoding in Huntington Disease

BACKGROUND

Anosognosia can manifest as an unawareness of neurobehavioral symptoms in individuals with Huntington disease (HD). Measurement of anosognosia is challenging, but the Anosognosia Scale (AS) represents a brief option with promising findings in small samples.

OBJECTIVE

To replicate application of the AS in a larger HD sample than previous studies in order to assess psychometrics and demographic correlates and to investigate the genetic, motor, and neuropsychological correlates of the AS in individuals with HD.

METHOD

We retrospectively reviewed the AS ratings of 74 genetically confirmed Huntington gene carriers, nearly all early motor manifest, who had been referred for clinical neuropsychological assessment. Concurrent clinical neurologic examination and neuropsychometric assessment data were compiled, where available (ns = 35-74). The severity of the anosognosia per AS ratings was characterized for the HD sample.

RESULTS

The AS ratings did not correlate with demographic variables, genetic markers, or motor dysfunction severity. Correlation analyses revealed that higher AS ratings correlated with worse recognition-discrimination memory performance (r = 0.38, P < 0.05) but not cognitive control on executive functioning performance or on collateral-reported frontal-behavioral symptoms. Higher AS ratings also correlated with fewer patient-reported depressive symptoms (r = -0.38, P < 0.01) and diurnal hypersomnia symptoms (r = -0.44, P < 0.01).

CONCLUSION

Anosognosia (per AS) is associated with recognition-discrimination deficits and fewer self-reported neuropsychiatric symptoms in individuals with pre-to-early manifest HD, though not with HD severity per genetic or motor markers, nor to executive dysfunction or collateral-reported frontal-behavioral symptoms.

Profiling Social Cognition in Premanifest Huntington's Disease

OBJECTIVE

Discrepancies exist in reports of social cognition deficits in individuals with premanifest Huntington's disease (HD); however, the reason for this variability has not been investigated. The aims of this study were to (1) evaluate group- and individual-level social cognitive performance and (2) examine intra-individual variability (dispersion) across social cognitive domains in individuals with premanifest HD.

METHOD

Theory of mind (ToM), social perception, empathy, and social connectedness were evaluated in 35 individuals with premanifest HD and 29 healthy controls. Cut-off values beneath the median and 1.5 × the interquartile range below the 25th percentile (P25 - 1.5 × IQR) of healthy controls for each variable were established for a profiling method. Dispersion between social cognitive domains was also calculated.

RESULTS

Compared to healthy controls, individuals with premanifest HD performed worse on all social cognitive domains except empathy. Application of the profiling method revealed a large proportion of people with premanifest HD fell below healthy control median values across ToM (>80%), social perception (>57%), empathy (>54%), and social behaviour (>40%), with a percentage of these individuals displaying more pronounced impairments in empathy (20%) and ToM (22%). Social cognition dispersion did not differ between groups. No significant correlations were found between social cognitive domains and mood, sleep, and neurocognitive outcomes.

CONCLUSIONS

Significant group-level social cognition deficits were observed in the premanifest HD cohort. However, our profiling method showed that only a small percentage of these individuals experienced marked difficulties in social cognition, indicating the importance of individual-level assessments, particularly regarding future personalised treatments.

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.

Predictors of Caregiver Burden in Huntington's Disease

OBJECTIVE

Huntington's disease (HD) is a genetic neurodegenerative condition that is characterized by cognitive, motor, and psychiatric dysfunction. The purpose of this study was to explore which disease characteristics influence caregiver burden in HD.

METHODS

Fifty participants with HD and 50 of their caregivers participated in the study at the University of South Florida. Participants were administered a neuropsychological battery, the Unified Huntington's Disease Rating Scale (UHDRS) motor exam, and the Frontal Systems Behavior Scale (FrSBe) self-report. Caregivers completed the Caregiving Appraisal Scale and the FrSBe family-report.

RESULTS

There were significant correlations between caregiver burden and caregiver age and sex, UHDRS motor scores, cognitive functioning, and self and caregiver-reported FrSBe scores. The significant variables were entered into a regression model and explained 63.1% of the variance in caregiver burden scores. Caregiver age, cognitive functioning, and caregiver-reported FrSBe scores continued to be significant predictors of caregiver burden, whereas the other variables were no longer significant.

CONCLUSIONS

There were significant relationships between caregiver burden, cognitive functioning, and frontally mediated behaviors, but not motor scores. The results suggest that possible interventions for caregivers may include education to caregivers on how to cope with apathy/executive dysfunction and cognitive decline. Caregiver age was associated with burden, with younger age being associated with increased burden when controlling for symptom severity. This has implications for this population in that HD typically has a younger age of onset than other neurodegenerative diseases and therefore, these caregivers may be particularly at risk for caregiver burden.