Computerised cognitive testing of individuals with Down's syndrome and Alzheimer's disease

BENDI: Improving Cognitive Assessments in Toddlers and Children with Down Syndrome Using Stealth Assessment

Cognitive assessment is a fundamental step in diagnosing intellectual and developmental disabilities, designing interventions, and evaluating their impact. However, developed and developing countries have different access to tools designed for these purposes. Our goal was to develop a battery for cognitive assessment mediated by digital technology that allows the exploration of cognitive domains (inhibitory control, attention, motor ability, and context memory) in children with Down Syndrome (DS) in Chile. Four tasks, based on established experimental paradigms modified to provide a game-like experience, were tested in 68 children with DS from 20 months to 12 years of age. We present evidence of reliability based on internal consistency and split-half analyses, with results ranging from adequate to excellent. Regarding validity, factorial and correlational analyses show evidence consistent with what was theoretically expected of internal structure, convergence, and divergence with other measures. Expected age trajectories were observed as well. Our data offer evidence that supports the use of tasks based on touch-screen devices for cognitive assessment in the population with DS. The tasks also have a low cultural load, so they could be validated and used in other contexts without the need for an adaptation process.

Physiological Mechanisms That Impact Exercise Adaptations for Individuals With Down Syndrome

ABSTRACT

Post, EM, and Kraemer, WJ. Physiological mechanisms that impact exercise adaptations for individuals with Down syndrome. J Strength Cond Res 37(12): e646-e655, 2023-Down syndrome (DS) is the most common chromosomal disorder diagnosed in the United States since 2014. There is a wide range of intellectual severities, with the average IQ of individuals with DS at approximately 50 and adults without intellectual delay at approximately 70-130. Individuals with DS vary from mild to severe cognitive impairment, depending on the phenotypic penetration on the 21st chromosome, with the average cognitive capacity equivalent to a cognitive functioning of an 8- to 9-year-old child. To have successful health, all aspects of health must be considered (i.e., overall health, fitness, and social). Both aerobic training and resistance training (RT) are favored for a healthy lifestyle. Resistance training specifically can help improve motor function and overall activities of daily living. Although many motivational and environmental barriers for individuals with DS can make exercising difficult, there are many ways to overcome those barriers (both intrinsically and extrinsically). Individuals with DS should strive for 150 minutes of moderate-intensity or 75 minutes of vigorous-intensity aerobic exercise a week or a combination of both. The individual should also strive for 2 or more days a week of strengthening activities, such as RT, involving all muscle groups. These activities will help improve many aspects of life, leading to a better quality of life. Regular group exercise activity can help increase self-confidence and success socially in life. This review will focus on the underlying biological mechanisms related to DS, their influence on exercise, and the roles exercise plays in mediating positive health, physical fitness, and social lifestyle outcomes.

Screening of Cognitive Changes in Adults with Intellectual Disabilities: A Systematic Review

Background and Aims: Screening and assessment of cognitive changes in adults with Intellectual Disabilities (ID), mainly Down Syndrome (DS), is crucial to offer appropriate services to their needs. We present a systematic review of the existing instruments assessing dementia, aiming to support researchers and clinicians’ best practice. Methods: Searches were carried out in the databases Web of Science; PubMed; PsycINFO in March 2019 and updated in October 2020. Studies were selected and examined if they: (1) focused on assessing age-related cognitive changes in persons with ID; (2) included adults and/or older adults; (3) included scales and batteries for cognitive assessment. Results: Forty-eight cross-sectional studies and twenty-seven longitudinal studies were selected representing a total sample of 6451 participants (4650 DS and 1801 with other ID). In those studies, we found 39 scales, questionnaires, and inventories, and 13 batteries for assessing cognitive and behavioural changes in adults with DS and other ID. Conclusion: The most used instrument completed by an informant or carer was the Dementia Questionnaire for Learning Disabilities (DLD), and its previous versions. We discuss the strengths and limitations of the instruments and outline recommendations for future use.

Cognitive decline and dementia in Down syndrome

PURPOSE OF REVIEW

Alzheimer's disease is most likely universal in older individuals with Down syndrome, due to having three copies of the amyloid precursor protein gene, resulting in amyloid-beta plaque deposition. Down syndrome is an important population in which to consider clinical trials of treatments to prevent or delay the development of dementia. However, assessment of subtler cognitive changes is challenging due to the presence of intellectual disability.

RECENT FINDINGS

Recent research confirmed that older adults with Down syndrome often present with cognitive decline: more than 80% may experience dementia by age 65 years. Efforts have been made to improve and validate neuropsychological assessment and to describe the relationship with comorbidities such as epilepsy and haemorrhagic stroke. There have also been advances in biomarkers such as neuroimaging using amyloid PET.

SUMMARY

Clinical trials of treatments, particularly in the presymptomatic phase of Alzheimer's disease, are important to consider in individuals with Down syndrome given their high dementia burden, and may also serve as proof of concept for other forms of Alzheimer's disease. However, further work is required to improve outcome measures and better understand the biomarkers of progression of disorder and their relationship with symptom development during the presymptomatic period.