The Behavioral and Psychological Symptoms of Dementia in Down Syndrome Scale (BPSD-DS II): Optimization and Further Validation

Symptoms and age of prodromal Alzheimer's disease in Down syndrome: a systematic review and meta-analysis

The diagnostic criteria for adult-onset Alzheimer's disease (AD) in patients with Down syndrome (DS) have not been standardised. This study investigated the specific symptoms of AD in the prodromal stage of DS, the mean age at diagnosis at each stage of dementia, and the relationship between intellectual disability (ID) and dementia. PubMed, Web of Science, and Embase were searched for studies on DS, AD, early-stage disease, initial symptoms, and prodromal dementia registered between January 2012 and January 2022. We also performed a meta-analysis of the differences between the mean age at prodromal symptoms and AD diagnosis and the proportion of mild cognitive impairment in patients with mild and moderately abnormal ID. We selected 14 articles reporting the behavioural and psychological symptoms of dementia (BPSD) and memory- and language-related impairments as early symptoms of AD in patients with DS. The specific symptoms of BPSD were classified into five categories: irritability (agitation), apathy, abnormal behaviour, adaptive functioning, and sleep disturbance. The mean age at the diagnosis of prodromal symptoms and AD dementia was 52.7 and 56.2 years, respectively (mean difference, + 3.11 years; 95% CI 1.82-4.40) in the meta-analysis. The diagnosis of mild dementia tended to correlate with ID severity (odds ratio [OR], 1.38; 95% CI 0.87-2.18). The features of behaviour-variant frontotemporal dementia may be clinically confirmed in diagnosing early symptoms of DS-associated AD (DSAD). Moreover, age-appropriate cognitive assessment is important. Further studies are required to evaluate DSAD using a combination of biomarkers and ID-related data.

Down Syndrome-Basque Alzheimer Initiative (DS-BAI): Clinic-Biological Cohort

BACKGROUND

Down syndrome (DS) is the most common genetically determined intellectual disability. In recent decades, it has experienced an exponential increase in life expectancy, leading to a rise in age-related diseases, including Alzheimer's disease (AD). Specific health plans for the comprehensive care of the DS community are an unmet need, which is crucial for the early and accurate diagnosis of main medical comorbidities. We present the protocol of a newly created clinical and research cohort and its feasibility in real life.

METHODS

The Down Syndrome-Basque Alzheimer Initiative (DS-BAI) is a population-based, inclusive, multidisciplinary initiative for the clinical-assistance and clinical-biological research approach to aging in DS led by the CITA-Alzheimer Foundation (Donostia, Basque Country). It aims to achieve the following: (1) provide comprehensive care for adults with DS, (2) optimize access to rigorous and quality training for socio-family and healthcare references, and (3) create a valuable multimodal clinical-biological research platform.

RESULTS

During the first year, 114 adults with DS joined the initiative, with 36% of them showing symptoms indicative of AD. Furthermore, adherence to training programs for healthcare professionals and families has been high, and the willingness to collaborate in basic and translational research has been encouraging.

CONCLUSION

Specific health plans for DS and conducting clinical and translational research on the challenges of aging, including AD, are necessary and feasible.

Maternal choline supplementation protects against age-associated cholinergic and GABAergic basal forebrain neuron degeneration in the Ts65Dn mouse model of Down syndrome and Alzheimer's disease

Down syndrome (DS) is a genetic disorder caused by triplication of human chromosome 21. In addition to intellectual disability, DS is defined by a premature aging phenotype and Alzheimer's disease (AD) neuropathology, including septohippocampal circuit vulnerability and degeneration of basal forebrain cholinergic neurons (BFCNs). The Ts65Dn mouse model recapitulates key aspects of DS/AD pathology, namely age-associated atrophy of BFCNs and cognitive decline in septohippocampal-dependent behavioral tasks. We investigated whether maternal choline supplementation (MCS), a well-tolerated treatment modality, protects vulnerable BFCNs from age- and genotype-associated degeneration in trisomic offspring. We also examined the effect of trisomy, and MCS, on GABAergic basal forebrain parvalbumin neurons (BFPNs), an unexplored neuronal population in this DS model. Unbiased stereological analyses of choline acetyltransferase (ChAT)-immunoreactive BFCNs and parvalbumin-immunoreactive BFPNs were conducted using confocal z-stacks of the medial septal nucleus and the vertical limb of the diagonal band (MSN/VDB) in Ts65Dn mice and disomic (2N) littermates at 3-4 and 10-12 months of age. MCS trisomic offspring displayed significant increases in ChAT-immunoreactive neuron number and density compared to unsupplemented counterparts, as well as increases in the area of the MSN/VDB occupied by ChAT-immunoreactive neuropil. MCS also rescued BFPN number and density in Ts65Dn offspring, a novel rescue of a non-cholinergic cell population. Furthermore, MCS prevented age-associated loss of BFCNs and MSN/VDB regional area in 2N offspring, indicating genotype-independent neuroprotective benefits. These findings demonstrate MCS provides neuroprotection of vulnerable BFCNs and non-cholinergic septohippocampal BFPNs, indicating this modality has translational value as an early life therapy for DS, as well as extending benefits to the aging population at large.

Assessing behavioral and psychological symptoms of dementia: a comprehensive review of current options and future perspectives

The behavioral and psychological symptoms of dementia (BPSD) are a heterogeneous set of challenging disturbances of behavior, mood, perception, and thought that occur in almost all patients with dementia. A huge number of instruments have been developed to assess BPSD in different populations and settings. Although some of these tools are more widely used than others, no single instrument can be considered completely satisfactory, and each of these tools has its advantages and disadvantages. In this narrative review, we have provided a comprehensive overview of the characteristics of a large number of such instruments, addressing their applicability, strengths, and limitations. These depend on the setting, the expertise required, and the people involved, and all these factors need to be taken into account when choosing the most suitable scale or tool. We have also briefly discussed the use of objective biomarkers of BPSD. Finally, we have attempted to provide indications for future research in the field and suggest the ideal characteristics of a possible new tool, which should be short, easy to understand and use, and treatment oriented, providing clinicians with data such as frequency, severity, and triggers of behaviors and enabling them to find appropriate strategies to effectively tackle BPSD.

Down syndrome and Alzheimer's disease: A scoping review of functional performance and fall risk

Introduction

Alzheimer's disease (AD) occurs in aging adults with Down syndrome (DS) at a higher prevalence and an earlier age than in typical aging adults. As with the general aging adult population, there is an urgent need to understand the preclinical and early phases of AD progression in the adult population with DS. The aim of this scoping review was to synthesize the current state of the evidence and identify gaps in the literature regarding functional activity performance and falls and their significance to disease staging (i.e., mild, moderate, and severe defined staging criteria) in relation to Alzheimer's disease and related dementias (ADRD) in adults with DS.

Methods

This scoping review included six electronic databases (e.g., PsycInfo, Academic Search Complete, CINAHL, COCHRANE Library, MEDLINE, and PubMed). Eligible studies included participants with DS ≥25 years of age, studies with functional measures and/or outcomes (e.g., activities of daily living, balance, gait, motor control, speech, behavior, and cognition; falls; and fall risks), and studies that investigated AD pathology and implications.

Results

Fourteen eligible studies were included and categorized through a thematic analysis into the following themes: (1) physical activity and motor coordination (PAMC), (2) cognition, (3) behavior, and (4) sleep. The studies indicated how functional activity performance and engagement may contribute to early identification of those at risk of cognitive decline and AD development and/or progression.

Discussion

There is a need to expand the research regarding ADRD pathology relative to functional outcomes in adults with DS. Functional measures related to disease staging and cognitive impairment are essential to understanding how AD progression is characterized within real-world settings. This scoping review identified the need for additional mixed-methods research to examine the use of assessment and intervention related to function and its detection of cognitive decline and AD progression.

Exploring the role of sex differences in Alzheimer's disease pathogenesis in Down syndrome

Women are disproportionately affected by Alzheimer's disease (AD), yet little is known about sex-specific effects on the development of AD in the Down syndrome (DS) population. DS is caused by a full or partial triplication of chromosome 21, which harbors the amyloid precursor protein (APP) gene, among others. The majority of people with DS in their early- to mid-40s will accumulate sufficient amyloid-beta (Aβ) in their brains along with neurofibrillary tangles (NFT) for a neuropathological diagnosis of AD, and the triplication of the APP gene is regarded as the main cause. Studies addressing sex differences with age and impact on dementia in people with DS are inconsistent. However, women with DS experience earlier age of onset of menopause, marked by a drop in estrogen, than women without DS. This review focuses on key sex differences observed with age and AD in people with DS and a discussion of possible underlying mechanisms that could be driving or protecting from AD development in DS. Understanding how biological sex influences the brain will lead to development of dedicated therapeutics and interventions to improve the quality of life for people with DS and AD.

Dementia in People with Severe/Profound Intellectual (and Multiple) Disabilities: Practice-Based Observations of Symptoms

INTRODUCTION

Observable dementia symptoms are hardly studied in people with severe/profound intellectual (and multiple) disabilities (SPI(M)D). Insight in symptomatology is needed for timely signaling/diagnosis. This study aimed to identify practice-based observations of dementia symptoms in this population.

METHODS

Care professionals and family members were invited to complete a survey about symptoms. Quantitatively analyzed survey data were further deepened through semi-structured interviews with care professionals having vast experience in signaling/diagnosing dementia in this population. Symptoms were categorized using a symptom matrix.

RESULTS

Survey respondents and interviewees frequently observed a decline in activities of daily living (ADL) functioning and behavioral and psychological changes, like increased irritability, anxiety, apathy and decreased eating/drinking behavior. Cognitive symptoms were particularly recognized in persons with verbal communication and/or walking skills. To lesser extent motor changes and medical comorbidities were reported.

CONCLUSION

Increased insight in dementia symptoms contributes to developing a dedicated screening instrument for dementia in people with SPI(M)D.

Dementia in people with severe or profound intellectual (and multiple) disabilities: Focus group research into relevance, symptoms and training needs

BACKGROUND

Differentiating dementia from baseline level of functioning is difficult among people with severe/profound intellectual (and multiple) disabilities. Moreover, studies on observable dementia symptoms are scarce. This study examined (a) the relevance of dementia diagnosis, (b) observable symptoms and (c) training/information needs.

METHODS

Four explorative focus groups were held with care professionals and family members who have experience with people with severe/profound intellectual (and multiple) disabilities (≥40 years) and decline/dementia.

RESULTS

Thematic analysis showed that participants wanted to know about a dementia diagnosis for a better understanding and to be able to make informed choices (question 1). Using a categorisation matrix, cognitive and behavioural changes were shown to be most prominent (question 2). Participants indicated that they needed enhanced training, more knowledge development and translation, and supportive organisational choices/policies (question 3).

CONCLUSIONS

Timely identifying/diagnosing dementia allows for a timely response to changing needs. This requires a better understanding of symptoms.

The neglected puzzle of dementia in people with severe/profound intellectual disabilities: A systematic literature review of observable symptoms

BACKGROUND

Dementia is increasingly prevalent in people with severe/profound intellectual disabilities. However, early detection and diagnosis of dementia is complex in this population. This study aimed to identify observable dementia symptoms in adults with severe/profound intellectual disabilities in available literature.

METHOD

A systematic literature search was conducted in PubMed, PsycINFO and Web of Science with an exhaustive search string using a combination of search terms for severe/profound intellectual disabilities and dementia/ageing.

RESULTS

Eleven studies met inclusion criteria. Cognitive decline, behavioural and psychological alterations, decline in activities of daily living as well as neurological and physical changes were found.

CONCLUSIONS

Only a very limited number of studies reported symptoms ascribed to dementia in adults with severe/profound intellectual disabilities. Given the complexity of signalling and diagnosing dementia, dedicated studies are required to unravel the natural history of dementia in this population.