Mild cognitive impairment with Lewy bodies: neuropsychiatric supportive symptoms and cognitive profile

BACKGROUND

Recently published diagnostic criteria for mild cognitive impairment with Lewy bodies (MCI-LB) include five neuropsychiatric supportive features (non-visual hallucinations, systematised delusions, apathy, anxiety and depression). We have previously demonstrated that the presence of two or more of these symptoms differentiates MCI-LB from MCI due to Alzheimer's disease (MCI-AD) with a likelihood ratio >4. The aim of this study was to replicate the findings in an independent cohort.

METHODS

Participants ⩾60 years old with MCI were recruited. Each participant had a detailed clinical, cognitive and imaging assessment including FP-CIT SPECT and cardiac MIBG. The presence of neuropsychiatric supportive symptoms was determined using the Neuropsychiatric Inventory (NPI). Participants were classified as MCI-AD, possible MCI-LB and probable MCI-LB based on current diagnostic criteria. Participants with possible MCI-LB were excluded from further analysis.

RESULTS

Probable MCI-LB (n = 28) had higher NPI total and distress scores than MCI-AD (n = 30). In total, 59% of MCI-LB had two or more neuropsychiatric supportive symptoms compared with 9% of MCI-AD (likelihood ratio 6.5, p < 0.001). MCI-LB participants also had a significantly greater delayed recall and a lower Trails A:Trails B ratio than MCI-AD.

CONCLUSIONS

MCI-LB is associated with significantly greater neuropsychiatric symptoms than MCI-AD. The presence of two or more neuropsychiatric supportive symptoms as defined by MCI-LB diagnostic criteria is highly specific and moderately sensitive for a diagnosis of MCI-LB. The cognitive profile of MCI-LB differs from MCI-AD, with greater executive and lesser memory impairment, but these differences are not sufficient to differentiate MCI-LB from MCI-AD.

Components of cognitive competence predictive of occupational competence in persons with dementia: a Delphi study

BACKGROUND

Within the area of dementia care, occupational therapists are asked to predict occupational competence in everyday living and often do so by assessing cognitive competence. Considering the cognitive changes that occur with dementia over time, the construct of cognitive competence is a key consideration. Still, a gap exists in the literature examining the relationship between cognitive competence and occupational competence.

PURPOSE

This study developed a consensus among participating Canadian occupational therapists regarding the components of cognitive competence they considered essential to predict occupational competence in people with dementia.

METHOD

A three-round Delphi study was completed with English- and French-speaking occupational therapists (n = 127; 116; 125) experienced in dementia care.

FINDINGS

Ten cognitive components were identified as essential to predict occupational competence in individuals with dementia.

IMPLICATIONS

The 10 identified components provide direction for assessment practices and education in dementia care and for development of measurement tools.

Measures of everyday competence in older adults with cognitive impairment: a systematic review

BACKGROUND

The issue of safety of the cognitively impaired elderly people living alone has been continuously raised. Traditional psychometric measures of cognitive abilities may not adequately reflect older adults' functioning in a real everyday context.

OBJECTIVES

To conduct a systematic review on instruments available for evaluating the everyday problem-solving or everyday competence of the elderly with cognitive impairment and to critically review the measurement properties of the identified instruments.

METHODS

We searched the databases such as Cinahl, Medline, PsycINFO, AARP Ageline, ProQuest and the Cochrane Library for the time period between January 1995 and December 2010. Reference lists of the included papers were also manually searched.

RESULTS

Five instruments were included. All the instruments focused their framework on Instrumental Activities of Daily Living (IADL) domains which meet well with suggestions from other studies on the importance of IADL in determining an elderly individual's capability to live independently in the community. No available instruments for the moderate to severe impairment group were identified under this review.

CONCLUSIONS

Few existing instruments to assess the ability of everyday problem-solving of the elderly with cognitive impairment can be identified in the literature. Further research validating them against functional, real-world outcomes is needed.

Expanding the ecological validity of WAIS-IV and WMS-IV with the Texas functional living scale

Assessment of functional status is an important aspect of clinical evaluation. As part of the standardization of the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) and Wechsler Memory Scale-Fourth Edition (WMS-IV), participants completed the Texas Functional Living Scale (TFLS), a measure of Instrumental Activities of Daily Living. The relationships between TFLS and WAIS-IV and WMS-IV were examined in both normally developing and clinical samples. In general, the highest correlations were between TFLS and measures of general cognitive ability (WAIS-IV FSIQ [Full Scale IQ] and GAI [General Ability Index]) and working memory (WAIS-IV WMI [Working Memory Index] and WMS-IV VWMI [Visual Working Memory Index]). Across the clinical populations, working memory subtests were generally strongly related to TFLS performance, although this relationship was more consistent with WAIS-IV than WMS-IV. Contrast scaled scores are presented for the TFLS based on WAIS-IV or WMS-IV performance. These scores allow the evaluation of functional abilities within the context of cognitive and memory ability, enhancing and expanding the utility of the WAIS-IV and WMS-IV.

The revised direct assessment of functional status for independent older adults

PURPOSE

The original version of the Direct Assessment of Functional Status (DAFS), a measure of instrumental activities of daily living (IADLs), was found to have a ceiling effect in older adults living independently in the community. This suggested that the tasks measured, although relevant, do not require full use of this population's abilities, and thus, the instrument may not be sensitive to the early decrements in IADLs that can signal initial cognitive impairment and may not detect improvements in IADLs over time, which is especially important in intervention research.

DESIGN AND METHODS

By removing items with little to no variation and adding more difficult subscales that emphasized medication management skills, we designed the DAFS-Extended (Direct Assessment of Functional Status-Revised [DAFS-R]) to be more challenging for elders living independently.

RESULTS

Analysis with a sample of 45 older adults suggested that scores on the DAFS-R appear to be more normally distributed than on the original version. The DAFS was able to differentiate individuals with varying standard profile scores on the Rivermead Behavioural Memory Test memory performance instrument (normal, poor, and impaired). In addition, the reliability and validity of the DAFS-R were supported in this sample.

IMPLICATIONS

Given the large number of older adults who regularly take multiple prescription medications, deficits in medication management skills can have serious consequences. A performance measure that emphasizes these higher level daily living skills can help providers screen for initial signs of functional decline.

Cognitive functioning and everyday problem solving in older adults

The relationship between cognitive functioning and a performance-based measure of everyday problem-solving, the Everyday Problems Test (EPT), thought to index instrumental activities of daily living (IADL), was examined in 291 community-dwelling non-demented older adults. Performance on the EPT was found to vary according to age, cognitive status, and education. Hierarchical regression analyses revealed that, after adjusting for demographic and health variables, measures of cognitive functioning accounted for 23.6% of the variance in EPT performance. In particular, measures of global cognitive status, cognitive decline, speed of processing, executive functioning, episodic memory, and verbal ability were significant predictors of EPT performance. These findings suggest that cognitive functioning along with demographic variables are important determinants of everyday problem-solving.

Comparative validity of seven scoring systems for the instrumental activities of daily living scale in rural elders

Lawton and Brody's eight-item Instrumental Activities of Daily Living (IADL) scale is used often with elderly patients but scored in several different ways. We scored the IADL with seven popular procedures ranging from relatively simple to complex (Guttman scores, summed and Rasch scores from dichotomous, trichotomous, and polytomous items) in a sample of rural elders (N = 231). We compared the IADL scales' prediction of concurrent cognitive functioning, depressive symptoms, psychosocial functioning, and health care use (medications, outpatient visits, inpatient days). Validity coefficients ranged from small to large among outcome variables but were highly consistent across IADL scoring procedures. Consequently, researchers and clinicians may prefer to use simpler IADL scoring procedures with this population.