Assessment of orientation: relationship between informant report and direct measures

Informant-based assessment instruments for dementia in people with intellectual disability: A systematic review and standardised evaluation

BACKGROUND

Dementia in people with intellectual disability (ID) is frequent but hard to recognise. Evidence-based recommendations for suitable instruments are lacking.

AIMS

The present study set out to evaluate informant-based dementia assessment instruments and to provide evidence-based recommendations for instruments most suitable in clinical practice and research.

METHOD AND PROCEDURES

A systematic review was conducted across ten international electronic databases. The COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) guidelines, including a risk of bias assessment, was applied to extract information and to evaluate measurement properties and the quality of available evidence.

OUTCOMES AND RESULTS

In total, 42 studies evaluating 18 informant-based assessment instruments were analysed. For screening purposes, we recommend the Behavioral and Psychological Symptoms of Dementia in Down Syndrome Scale (BPSD-DS), the Cognitive Scale for Down Syndrome (CS-DS), and the Dementia Screening Questionnaire for Individuals with Intellectual Disabilities (DSQIID). For a more thorough dementia assessment, we recommend the Cambridge Examination for Mental Disorders of Older People with Down's Syndrome and Others with Intellectual Disabilities (CAMDEX-DS).

CONCLUSIONS AND IMPLICATIONS

Our study informs clinicians and researchers about adequate, well-evaluated dementia assessment instruments for people with ID, and highlights the need for high quality studies, especially regarding content validity.

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.

A validity study of the Working Group's Orientation Test for individuals with moderate to severe intellectual disability

BACKGROUND

Decline in orientation skill has been reported as an early indicator of Dementia of Alzheimer's Type (DAT). Orientation subtest of the Working Group's Test Battery was examined whether this test is useful to identify DAT patients among adults with moderate to severe ID.

METHODS

Sixteen DAT patients and 35 non-demented normal controls with moderate to severe ID were followed for a year using Orientation Test. The scores on the baseline evaluation and the longitudinal changes over a 1-year period among the DAT patients and the normal controls were compared. The effects of age and etiologies of ID on the performance of Orientation were also examined.

RESULTS

The DAT group's score was significantly poorer than that of the normal control group on the baseline evaluation. The score changes over the 1-year period were not significantly different between the groups. However, there was a considerable overlap between the score distributions of the two groups. The effects of age and etiologies of ID on the performance of Orientation were not significant.

CONCLUSIONS

Screening DAT patients based only on the score of the Orientation Test of the Working Group's Test Battery may produce a large number of diagnostic errors.

Diagnostic instruments for dementia in older people with intellectual disability in clinical practice

There is a need for simple and reliable screening instruments for dementia in the intellectual disability (ID) population that can also be used to follow their progress, particularly if they are being treated with anti-dementia drugs. Commonly used tests for the general population such as the Mini Mental State Examination (MMSE) are not appropriate for many people with ID. This paper is a literature review of alternative instruments that have been used in research or recommended by experts since 1991 and have the potential to be used as screening instruments. Two types of tests have been identified: those administered to informants, and those that rely on direct assessment of the individual. The most promising informant rated screening tool in most adults with ID including Down syndrome (DS) diagnosis is the Dementia Questionnaire for Persons with Mental Retardation (DMR). However, sensitivity in single assessments is variable and cut-off scores need further optimisation. In those with DS, the Dementia Scale for Down Syndrome (DSDS) has good specificity but mediocre sensitivity. The Test for Severe Impairment and Severe Impairment Battery are two direct assessment tools that show promise as screening instruments, but need further evaluation.

Neurological changes and emotional functioning in adults with Down Syndrome

This study was designed to examine emotional changes in adults with Down Syndrome (DS) over time and whether changes in these psychological variables were associated with brain atrophy on MRI scan and the presence of pathological reflexes on the neurological examination. Participants were 26 adults with DS and their caregivers. Caregivers completed a measure of emotional functioning about individuals with DS at two different time points (1 year apart). Levels of cognitive functioning were measured and neurological and MRI examinations were performed on all subjects at initial testing. Significant group effect separated those with and without pathological findings on MRI and neurological exam across three different scales: depression, indifference, and pragmatic language functioning. Problems of poor pragmatic language functioning appeared later in the course of suspected Alzheimer's disease (AD), as demonstrated by a significant group effect at time 2, but not at initial testing. In these subjects, the primary emotional change was a decline in social discourse (e.g. conversational style, literal understanding, verbal expression in social contexts). These emotional levels were stable over time, regardless of degree of cognitive decline. Specific emotional changes occur during the course of AD which were associated with abnormal findings from MRI and from neurological examination. These results, along with abnormalities in brain imaging and the presence of pathological reflexes, suggested that frontal lobe dysfunction is likely to be an early manifestation of Alzheimer's Disease in Down Syndrome.

Test battery for the diagnosis of dementia in individuals with intellectual disability. Working Group for the Establishment of Criteria for the Diagnosis of Dementia in Individuals with Intellectual Disability

A working battery of tests for the diagnosis of dementia, which is applicable to most adults with intellectual disability, is proposed by an international Working Group. The battery, reflecting contemporary research and practice findings, includes scales for informant report of functioning and tests for direct assessment. The Working Group recommends the international use of the battery both as part of ongoing and new longitudinal research, and in clinical practice. The widespread use of a common battery will enhance communication and collaborative opportunities among researchers and clinicians at various sites, and will help to standardize diagnostic protocols and research findings. The collaborative evaluation of such a battery will address one of the greatest challenges in the field, that of differentiating change associated with ageing from that associated with dementia.