Evaluation of Three Tests to Assess Social Cognition in Huntington Disease

The Social-HD Study: A Cross-Sectional Observational Study of Social Cognition in Early Huntington Disease

The goal of this observational study is to learn about the usefulness of a test of social functioning in persons with Huntington disease. Huntington disease affects motor function, psychological well-being and cognitive functions ("thinking abilities" such as paying attention, remembering and solving problems). It is also believed to affect important social functions, including the ability to understand others' intentions and emotions (social cognition). The test of interest in this study is called The Double Movie for the Assessment of Social Cognition-Multiple Choice (DMASC-MC) and will be compared to two other similar and well-known tests. The main question which the study aims to answer is:

• Is DMASC-MC a useful tool for detecting problems with social functioning in adult persons with early Huntington disease? In the study, participants will meet with a medical doctor and a psychologist for assessment of different symptoms related to Huntington disease, including social functioning. Better methods for identifying problems with social functioning could help persons with Huntington disease and their families in mainly two ways. Firstly, it could increase their understanding of how the disease has affected them. Secondly, a better understanding of these problems could lead to better recommendations and interventions from medical teams, which would also benefit persons with Huntington disease and families.

Background:

Huntington disease (HD) is a fatal neurodegenerative disorder that leads to motor disturbances, psychiatric symptoms and dementia. It is caused by an expanded CAG repeat in the huntingtin (HTT) gene which is inherited in an autosomal dominant fashion with full penetrance. It typically manifests in midlife. There are no disease-modifying therapies and current care is focused on reducing symptoms and improving quality of life. An important understudied part of the clinical manifestation is the early development of personality changes that have major impact on most aspects of the life of the affected person. These changes may be due to altered social cognition. Today, assessment of social cognition is often not part of the neuropsychological battery for HD and the so far investigated tests may not capture sufficient aspects of altered social cognition.

Aim:

The aim is to investigate whether the social cognitive test "Double Movie for the Assessment of Social Cognition-Multiple Choice (DMASC-MC) " will detect a significant difference in persons with early stages of HD compared to age and sex matched controls.

Methods:

This clinical research study will include 20 persons with early HD and 20 matched controls. The number of participants is based on a power calculation. The research participants will be assessed using DMASC-MC as well as two other tests for social cognition, Reading the Mind in the Eyes Test and The Emotion Hexagon Test. They will also be evaluated for typical cognitive deficits, psychiatric symptoms and motor aspects in HD.

Relevance:

This study aims to bridge an important gap in clinical care where evaluation of social cognition is not yet part of standard assessments. Determination of social cognitive deficits will be important for planning care and facilitate communication for HD families.

Inclusion Criteria:

Inclusion criteria for persons with HD

1. Clinical diagnosis of HD
2. CAG repeat: 40 and more

Inclusion criteria for control group

1. No heritage of HD or negative pre-symptomatic HD gene test

Exclusion Criteria:

Participants in both groups are excluded from the study if any of the following criteria apply:

1. Dementia or MOCA<19, The Mini Mental State Examination (MMSE) <19
2. Other neurological disorders
3. Ongoing psychosis
4. Ongoing alcohol/drug addiction
5. Other native language than Swedish
6. Severe problems with vision and hearing