Impact of impairment in instrumental activities of daily living and mild cognitive impairment on time to incident dementia: results of the Leipzig Longitudinal Study of the Aged

Association Between Neuropsychological Functions and Activities of Daily Living in People with Mild Cognitive Impairment

OBJECTIVE

The aim of this study was to explore the relationship between performance in neurocognitive variables and daily functioning (basic or b- and instrumental or i-ADL) in people with mild cognitive impairment (MCI).

METHODS

A sample of 157 participants with MCI (73.65 ± 7.58 years) completed a battery of tests for assessing ADL and cognitive functions. t-test, Pearson's correlation and multiple linear regression (backward stepwise selection) were used for data analyses.

RESULTS

Significant correlations were found between b- and i-ADL, and several neuropsychological tests (p < .01). Multivariate analysis showed that difficulties in Blessed Rating Scales (BLS) explained 33.2% of the variation in b-ADL and that this variation rises to 42.9% when BLS is associated with Frontal Assessment Battery Flexibility, Trail Making Test A (TMT-A) and BLS Personality. For i-ADL, BLS and Dementia Rating Scale Total (DRS-T) explained 47.7% of the variation and the inclusion in the model of BLS, DRS-IP (Initiation/Perseveration), TMT-A and BLS Personality explained 53.5% of this variation. Executive functions explained 24.8% of the variation in i-ADL.

CONCLUSIONS

Cognitive functions are related to i- and b-ADL in people with MCI. The general indicators and those that assess executive functions and verbal- or visual-spatial memory should be considered to predict i-ADL.

Lawton's Instrumental Activities of Daily Living for Greek-Speaking Adults with Cognitive Impairment: A Psychometric Evaluation Study with Additional Receiver Operating Characteristic Curve Analysis

One of the components of a dementia diagnosis is the assessment of functional abilities. These abilities are measured via screeners, such as the Instrumental Activities of Daily Living (IADL) scale. The IADL scale is a valid tool that has been adapted in many languages. This study aimed to provide a cut-off point and validate the Greek version of the IADL scale in populations with cognitive impairment. IADL data were collected from 132 individuals: 24 PD patients, 24 Parkinson's disease dementia (PDD) patients, and 24 AD patients. The remaining 60 participants were cognitive healthy adults (CHAs). The CHA group and the PD group served as the cognitively unimpaired group (CUG), while the PDD and AD groups served as the cognitively impaired group (CIG). Additionally, the MMSE, the AMTS, the Clock Drawing Test CDT, the Arizona Battery for Communication Disorders of Dementia (ABCD), the NPI, and the GDS-15 were administered to the participants. Statistically significant differences in the IADL scores were exhibited between all subgroups. The IADL scale showed high internal consistency (Cronbach's alpha = 0.890). A threshold equal to 6.00 (AUC = 0.888, p < 0.001) was estimated between the CUG and the CIG. Significant positive correlations were observed between IADL and MMSE (r = 0.764, p < 0.001), IADL and AMTS (r = 0.724, p < 0.001), IADL and ABCD (r = 0.702, p < 0.001), and IADL and CDT (r = 0.627, p < 0.001) results. Given the obtained results, the IADL scale is a valid tool for clinical use with high reliability and sensitivity. Also, the IADL scale is a valuable instrument for screening functional abilities associated with cognitive impairment.

NEURONORMA Cognitive Battery Associations with Cerebrospinal Fluid Amyloid-β and Tau Levels in the Continuum of Alzheimer's Disease

BACKGROUND

Neuropsychological assessments are essential to define the cognitive profile and contribute to the diagnosis of Alzheimer's disease (AD). The progress in knowledge about the pathophysiological process of the disease has allowed conceptualizing AD through biomarkers as a biological continuum that encompasses different clinical stages.

OBJECTIVE

To explore the association between cerebrospinal fluid (CSF) biomarkers of AD and cognition using the NEURONORMA battery, in a sample of cognitively unimpaired (CU), mild cognitive impaired (MCI), and mild dementia of the Alzheimer type (DAT) subjects, and to characterize the cognitive profiles in MCI subjects classified by A/T/N system.

METHODS

42 CU, 35 MCI, and 35 mild DAT were assessed using the NEURONORMA battery. Core AD biomarkers [amyloid-β42 (Aβ42) peptide, total tau (t-tau), and phosphorylated tau 181 (p-tau181)] proteins were measured in CSF. Correlation coefficients, multivariate regression, and effect sizes were calculated. We explored the age- and education-adjusted cognitive profiles by A/T/N variants within the MCI group.

RESULTS

Cognitive outcomes were directly associated with CSF Aβ42 and inversely with CSF tau measures. We found differences in both biomarkers and cognitive outcomes comparing all pairs except for CSF measures between cognitively impaired groups. The highest effect size was in memory tasks and biomarkers ratios. Lower performances were in memory and executive domains in MCI subjects with AD pathology (A+T+N±) compared to those with normal levels of AD biomarkers (A- T- N).

CONCLUSION

This study provides further evidence of the validity of Spanish NEURONORMA cognitive battery to characterize cognitive impairment in the AD pathological continuum.

Capturing Cognitive Aging in Vivo: Application of a Neuropsychological Framework for Emerging Digital Tools

As the global burden of dementia continues to plague our healthcare systems, efficient, objective, and sensitive tools to detect neurodegenerative disease and capture meaningful changes in everyday cognition are increasingly needed. Emerging digital tools present a promising option to address many drawbacks of current approaches, with contexts of use that include early detection, risk stratification, prognosis, and outcome measurement. However, conceptual models to guide hypotheses and interpretation of results from digital tools are lacking and are needed to sort and organize the large amount of continuous data from a variety of sensors. In this viewpoint, we propose a neuropsychological framework for use alongside a key emerging approach—digital phenotyping. The Variability in Everyday Behavior (VIBE) model is rooted in established trends from the neuropsychology, neurology, rehabilitation psychology, cognitive neuroscience, and computer science literature and links patterns of intraindividual variability, cognitive abilities, and everyday functioning across clinical stages from healthy to dementia. Based on the VIBE model, we present testable hypotheses to guide the design and interpretation of digital phenotyping studies that capture everyday cognition in vivo. We conclude with methodological considerations and future directions regarding the application of the digital phenotyping approach to improve the efficiency, accessibility, accuracy, and ecological validity of cognitive assessment in older adults.

Sex differences in risk factors that predict progression from mild cognitive impairment to Alzheimer's dementia

OBJECTIVES

To evaluate whether cerebrospinal fluid biomarkers, apolipoprotein e4, neuroimaging abnormalities, and neuropsychological data differentially predict progression from mild cognitive impairment (MCI) to dementia for men and women.

METHODS

Participants who were diagnosed with MCI at baseline (n = 449) were classified as either progressing to Alzheimer's dementia at follow-up or as not progressing. Men and women were first compared using bivariate analyses. Sex-stratified Cox proportional hazard regressions were performed examining the relationship between baseline data and the likelihood of progressing to dementia. Sex interactions were subsequently examined.

RESULTS

Cox proportional hazard regression controlling for age and education indicated that all variables significantly predicted subsequent progression to dementia for men and women. Sex interactions indicated that only Rey Auditory Verbal Learning Test (RAVLT) delayed recall and Functional Activities Questionnaire (FAQ) were significantly stronger risk factors for women. When all variables were entered into a fully adjusted model, significant risk factors for women were Aβ42, hippocampal volume, RAVLT delayed recall, Boston Naming Test, and FAQ. In contrast, for men, Aβ42, p-tau181, p-tau181/Aβ42, hippocampal volume, category fluency and FAQ were significant risk factors. Interactions with sex were only significant for p-tau181/Aβ42 and RAVLT delayed recall for the fully adjusted model.

CONCLUSIONS

Men and women with MCI may to differ for which factors predict subsequent dementia although future analyses with greater power are needed to evaluate sex differences. We hypothesize that brain and cognitive reserve theories may partially explain these findings.

The Cognitive Scale of Basic and Instrumental Activities of Daily Living for Multidomain Mild Cognitive Impairment and Dementia Patients: Validation of its Extended Version

OBJECTIVE

To validate an informant-based tool - the extended version of the Cognitive Scale of Basic and Instrumental Activities of Daily Living (BADL and IADL) or Ext. Cog-ADL Scale - in a larger sample and with a broader range of cognitive-functional items related to activities of daily living (ADL).

METHOD

The Ext. Cog-ADL Scale was administered to family informants of 42 patients with dementia, 43 patients with multidomain mild cognitive impairment (mdMCI), and 23 healthy control participants. We analyzed the convergent and concurrent validity and external validity of this scale.

RESULTS

The Ext. Cog-ADL Scale demonstrated good psychometric properties. Episodic and working memory tests were the main predictors of most cognitive-functional items of the scale. While patients with dementia obtained lower scores in most error categories of the scale, affecting both BADL and IADL, mdMCI patients showed a more specific pattern of difficulties. Apart from the typical alterations in IADL, mdMCI patients also showed difficulties in several error categories related to BADL (i.e., error detection, problem solving, task self-initiation, distraction inhibition, and restore).

CONCLUSIONS

The Ext. Cog-ADL Scale seems to be an adequate tool to capture the specific pattern of cognitive alterations related to IADL and BADL that differentiates dementia from mdMCI and healthy aging; it shows that mdMCI can involve specific cognitive difficulties that affect even BADL.

Trajectories of decline on instrumental activities of daily living prior to dementia in persons with mild cognitive impairment

OBJECTIVES

The main objective was to determine the trajectory of instrumental activities of daily living (iADL) decline in persons with mild cognitive impairment (MCI) who progressed towards dementia relative to persons with MCI who remained stable.

METHODS/DESIGN

At study entry, 121 participants met criteria for MCI. Based on the follow-up, 47 participants later converted to dementia and were identified as progressors. Sixteen participants, identified as decliners, presented a significant cognitive decline but did not reach the criteria for dementia within the study timeframe. Stable MCI remained cognitively stable during the 5-year follow-up; n = 58. Participants completed a yearly assessment using clinical tests/questionnaires, neuropsychological measures, and functional autonomy assessment until they met criteria for dementia. The average number of months for the follow-up was 34.

RESULTS

Many years of stable performance followed by an accelerated decline just prior to diagnosis, was observed for complex activities for progressors. No change was found for stable MCI and a gradual linear decline characterized decliners. The housekeeping-related activities component showed a linear decline in progressors and did not change in stable and decliner MCI. We found a predictive model that includes significant predictors of dementia conversion with a high diagnostic accuracy the following year (area under the curve = 0.94 [95% confidence level; lower bound: 0.87, upper bound: 1]).

CONCLUSIONS

It is critical to assess iADL that reflect complex activities in the evaluation of MCI individuals as their impairment, combined with change on cognitive markers, indicates a higher risk of dementia progression 1 or 2 years later.

Assessing functional status using the IADL-extended scale: results from the HELIAD study

OBJECTIVES

Instrumental activities of daily living (IADL) have been operationalized as exhibiting a greater level of complexity than basic ADL. In the same way, incorporating more advanced ADLs may increase the sensitivity of functional measures to identify cognitive changes that may precede IADL impairment. Towards this direction, the IADL-extended scale (IADL-x) consists of four IADL tasks and five advanced ADLs (leisure time activities).

DESIGN

Retrospective, cross-sectional study.

SETTING

Athens and Larissa, Greece.

PARTICIPANTS

1,864 community-dwelling men and women aged over 64.

MEASUREMENTS

We employed both the IADL-x and IADL scales to assess functional status among all the participants. Diagnoses were assigned dividing the population of our study into three groups: cognitively normal (CN), mild cognitive impairment (MCI) and dementia patients. Neuropsychological evaluation was stratified in five cognitive domains: memory, language, attention-speed, executive functioning and visuospatial perception. Z scores for each cognitive domain as well as a composite z score were constructed. Models were controlled for age, sex, education and depression.

RESULTS

In both IADL-x and IADL scales dementia patients reported the most functional difficulties and CN participants the fewest, with MCI placed in between. When we restricted the analyses to the CN population, lower IADL-x score was associated with worse cognitive performance. This association was not observed when using the original IADL scale.

CONCLUSION

There is strong evidence that the endorsement of more advanced IADLs in functional scales may be useful in detecting cognitive differences within the normal spectrum.

The power of the Functional Activities Questionnaire for screening dementia in rural-dwelling older adults at high-risk of cognitive impairment

AIM

A simple approach to detecting dementia in its early stages may help improve patient care. We therefore aimed to assess the power of the Functional Activities Questionnaire (FAQ) for screening dementia among rural-dwelling older adults who are at high-risk for cognitive impairment.

METHODS

This study included 961 participants at a high-risk for dementia who had been identified from a population-based survey of Chinese rural residents. All participants were aged 65 years and older and positive for cognitive impairment according to the Mini-Mental State Examination or the Ascertain Dementia 8-item Informant Questionnaire screening tests. The FAQ scale was used to evaluate daily activities. Dementia was diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, criteria. Receiver operating characteristic curve analyses were used to determine the FAQ's optimal cut-offs for dementia. The power (or accuracy) of the FAQ for screening dementia was analyzed in the total sample and in subgroups categorized by age, gender, and educational level.

RESULTS

Of the 961 participants, 84 (8.7%) were clinically diagnosed with dementia. Among individuals who were positive for cognitive impairment on the Mini-Mental State Examination or the Ascertain Dementia 8-item Informant Questionnaire, the parameters for an FAQ cut-off score ≥6 as a means of discriminating those with dementia from those without dementia were area under curve = 0.899, sensitivity = 94.1%, specificity = 75.1%, positive likelihood ratio = 3.78, and accuracy = 0.768. The discriminant abilities of the FAQ scale varied with age, gender, and educational level. The discriminant parameters of the FAQ scale were similar overall among individuals who were positive on either the Mini-Mental State Examination or the Ascertain Dementia 8-item Informant Questionnaire test alone.

CONCLUSION

The FAQ scale has high discriminative power to screen for dementia among rural older residents with suspected cognitive impairment.

Memory and Executive Dysfunction Predict Complex Activities of Daily Living Impairment in Amnestic Multi-Domain Mild Cognitive Impairment

BACKGROUND

Specific cognitive alterations could be one of the predictors that lead to the complex activities of daily living (CADL) impairment in mild cognitive impairment (MCI) and, hence, help to explain the continuum between MCI and dementia.

OBJECTIVE

We aimed to reevaluate the existing uncertainty regarding the impact of memory and executive functions on CADL in patients with MCI.

METHODS

Caregivers of 161 patients with amnestic multi-domain MCI and of 150 patients with incipient Alzheimer's disease as well as 100 age-, sex-, and education-matched controls, completed the Interview for Deterioration in Daily Living Activities in Dementia, a suitable instrument for the description and discrimination of CADL. In addition, all patients and controls were assessed with a neuropsychological battery to measure explicit memory and executive functions performance.

RESULTS

Multiple regression analyses showed that in the group of patients with amnestic multi-domain MCI, 67.4% of the variability of the CADL impairment was explained by worse performance on executive functions tests (p < 0.0001) and 41.8% by different explicit memory components impairment (p < 0.0001). Further, in patients with incipient AD, 44.0% of the variability of CADL impairment was explained by worse performance on executive functions tests (p < 0.0001) and 39.9% by different explicit memory components worsening (p < 0.0001).

CONCLUSIONS

Memory and executive functions alterations impact similarly on the CADL in both amnestic multi-domain MCI and incipient Alzheimer's disease. Given the continuum that exists between both conditions, we conclude that CADL impairment may be an important early step in the evolution towards Alzheimer's disease from amnestic multi-domain MCI.

Determinants of incident dementia in different old age groups: results of the prospective AgeCoDe/AgeQualiDe study

OBJECTIVES

To examine the impact of determinants of incident dementia in three different old age groups (75-79, 80-84, 85+years) in Germany.

DESIGN

Multicenter prospective AgeCoDe/AgeQualiDe cohort study with baseline and nine follow-up assessments at 1.5-year intervals.

SETTING

Primary care medical record registry sample.

PARTICIPANTS

General practitioners' (GPs) patients aged 75+years at baseline.

MEASUREMENTS

Conduction of standardized interviews including neuropsychological assessment and collection of GP information at each assessment wave. We used age-stratified competing risk regression models (accounting for the competing event of mortality) to assess determinants of incident dementia and age-stratified ordinary least square regressions to quantify the impact of identified determinants on the age at dementia onset.

RESULTS

Among 3027 dementia-free GP patients, n = 704 (23.3%) developed dementia during the 13-year study period. Worse cognitive performance and subjective memory decline with related worries at baseline, and the APOE ε4 allele were associated independently with increased dementia risk in all three old age groups. Worse cognitive performance at baseline was also associated with younger age at dementia onset in all three age groups. Other well-known determinants were associated with dementia risk and age at dementia onset only in some or in none of the three old age groups.

CONCLUSIONS

This study provides further evidence for the age-specific importance of determinants of incident dementia in old age. Such specifics have to be considered more strongly particularly with regard to potential approaches of early detection and prevention of dementia.

Independent Older Adult's IADL and Executive Function According to Cognitive Performance

Participation in Instrumental Activities of Daily Living (IADL) is essential in occupational therapy aiming to improve the life situation of elderly. Effective executive function (EF) is important to successful functioning in IADL. The purpose of this study was to examine EF and IADL performance differences according to cognitive levels as measured by the Montreal Cognitive Assessment (MoCA), age, and gender. In all, 80 elderly (49% female; age M = 73.4) were assessed at home, with Weekly Calendar Planning Activity (WCPA-10), IADL scale, and MoCA as a cognitive screening tool for dividing into normal cognitive (NC) level and mild cognitive impairment (MCI). The comparison between the MoCA groups on the WCPA-10 and IADL shows significant differences between the groups; gender and age differed only in IADL. IADL and WCPA-10 performance among independent elderly relates to their cognitive level. We suggest that intervention that will focus on EF may assist in improving performance and maintaining participation in occupation.

The Historical Progression From ADL Scrutiny to IADL to Advanced ADL: Assessing Functional Status in the Earliest Stages of Dementia

Background

Decrements in instrumental activities (IADL) have been observed in the prodromal phase of dementia. Given the long predementia stage in neurodegenerative diseases, it has been proposed that subtle functional changes may precede clinical IADL impairment. Incorporating more challenging advanced ADLs (eg, volunteer work) into the assessment process may increase the sensitivity of functional measures, thus expanding the window for monitoring or interventions.

Methods

Longitudinal cohort study was used (follow-ups, 18-24 month), with subjects aged 60 and older (n = 3,635). To elucidate the relationship between cognitive ability and functional status we employed an IADL scale with an extended range (ADL-extended; includes IADL but also more challenging advanced ADLs) that meets item response theory properties of dimensionality, monotonicity, and item hierarchy. Procedures involved (a) a dynamic change model employed to inspect the temporal relationship between ADL-extended and cognitive status and (b) Cox proportional hazards to assess the risk of incident dementia based on ADL-extended scores.

Results

Growth curve modeling: baseline ADL-extended was significantly associated with all four cognitive domains investigated. Worse baseline ADL-extended was associated with more rapid declines in speed/executive function, and worse baseline memory was associated with more rapid declines in ADL-extended; a concurrent association was found for language and ADL-extended. Cox model: the risk of dementia was decreased for each additional ADL-extended item endorsed (hazard ratio [HR], 0.85; 95% confidence interval = 0.81-0.90).

Conclusions

An increased risk of dementia could be observed in the ADL-extended items, which reflects an area of the functional continuum beyond IADL competencies.

Inferior and medial temporal tau and cortical amyloid are associated with daily functional impairment in Alzheimer's disease

BACKGROUND

A decline in instrumental activities of daily living (IADL) correlates with the progression from mild cognitive impairment (MCI) to Alzheimer's disease (AD) dementia and has been associated with frontal and parietal hypometabolism, lower cerebrospinal fluid amyloid β1-42, and inferior temporal cortical thinning. Identifying the underlying biomarkers of functional decline will allow for the early identification of individuals at risk of disease progression.

OBJECTIVE

To investigate the association between IADL impairment and in vivo regional cerebral tau and cortical amyloid deposition across clinically normal (CN) elderly, MCI, and AD dementia.

METHODS

Fifty-one CN elderly, 30 MCI, and 9 AD dementia participants of the Alzheimer's Disease Neuroimaging Initiative (ADNI) underwent assessment of regional tau deposition with flortaucipir (FTP) positron emission tomography (PET). An aggregate of cortical amyloid burden was assessed by florbetapir PET. IADL were assessed using the Functional Activities Questionnaire (FAQ). Tau regions with unadjusted correlations of p ≤ 0.006 (Bonferroni correction) with FAQ were used to evaluate the cross-sectional association between FAQ (dependent variable) and regional cerebral tau deposition, amyloid burden, and tau-amyloid interaction in separate general linear regression models with backward elimination. Covariates included age, American National Adult Reading Test (AMNART) intelligence quotient (IQ), and Rey Auditory Verbal Learning Test (RAVLT) total learning.

RESULTS

Unadjusted correlations between FAQ and tau in the entorhinal cortex (EC) and inferior temporal cortex (IT) survived Bonferroni correction. FAQ was associated with the tau-amyloid interaction, such that in participants with greater amyloid burden, greater IADL impairment was associated with greater regional tau (EC tau × amyloid: partial r (pr) = 0.47, p < 0.001; IT tau × amyloid: pr = 0.54, p < 0.001). Significant associations were found when these regression models were repeated in symptomatic participants alone but not among CN participants.

CONCLUSIONS

Greater medial and inferior temporal tau and cortical amyloid burden were associated with greater IADL impairment in AD. Further elucidation of the biomarkers underlying the functional decline will allow for the early identification of individual at risk of disease progression.

Neuropsychological correlates of instrumental activities of daily living in neurocognitive disorders: a possible role for executive dysfunction and mood changes

ABSTRACTSince baseline executive dysfunction predicts worsening Instrumental Activities of Daily Living (i-ADL) over time and progression to Alzheimer's Disease (AD), we aimed to analyze the role of neuropsychological variables to outline which factors can contribute to functional impairment. Specific attention to executive functions (EFs) has been given.A total of 144 subjects complaining of different cognitive deficits - ranging from "MCI likely due to AD" to "mild AD patients" - underwent an overall neuropsychological assessment. The Behavioral Assessment of the Dysexecutive Syndrome was used to analyze EFs. We conducted multiple linear regression analyses to study whether the level of independent living skills - assessed with the Lawton-scale - could be associated with cognitive and behavioral measurements.We found a significant association between i-ADL and specific EFs measured by Rule Shift Cards (p = 0.04) and Modified Six Elements (p = 0.02). Moreover, considering i-ADL scores, we observed an involvement of mood changes and a reduced awareness of deficits in terms of Hamilton Depression Rating Scale (p = 0.02) and Awareness of Deficit Questionnaire - Dementia scale (p &lt; 0.0001), respectively.Our results suggest the importance of considering the association between a reduction in i-ADL and executive dysfunction in patients who have AD etiopathology, for which the ability to inhibit a response, self-monitoring, set-shifting and mood deflection play a key role. Besides, no straightforward associations between i-ADL scores and global cognition, memory, language comprehension, attention, and perspective taking abilities were found.

Relationships between socio-clinico-demographic factors and global cognitive function in the oldest old living in the Tokyo Metropolitan area: Reanalysis of the Tokyo Oldest Old Survey on Total Health (TOOTH)

BACKGROUND

Despite a steady increase in life expectancy, a few studies have investigated cross-sectional correlates and longitudinal predictors of cognitive function, a core domain of the successful aging, among socio-clinico-demographic factors in the oldest-old exclusively.

OBJECTIVES

The aims of this study were to examine socio-clinico-demographic characteristics associated with global cognition and its changes in the oldest-old.

METHODS

We reanalyzed a dataset of cognitively preserved community-dwelling subjects aged 85 years and older in the Tokyo Oldest Old Survey on Total Health, a 6-year longitudinal observational study. This study consisted of (1) baseline cross-sectional analyses examining correlates of global cognition (n = 248) among socio-clinico-demographic factors and (2) longitudinal analyses examining baseline predictors for changes of global cognition in 3-year follow-up (n = 195). The Mini-Mental State Examination was used as a screening test to assess global cognition.

RESULTS

At baseline, higher weights were related to higher cognitive function in the oldest-old. The baseline predictors of global cognitive decline in 3-year follow-up were higher global cognition, shorter education period, and lower sociocultural activities and lower instrumental activity of daily living, in this order.

CONCLUSIONS

The present study suggests that it is crucial to attain higher education during early life and avoid leanness or obesity, participate in sociocultural cognitive activities during late life, and maintain instrumental activity of daily living to preserve optimal cognitive function in the oldest-old, which will facilitate developing prevention strategies for cognitive decline and promoting successful aging in this increasing population.

Diagnostic accuracy of Instrumental Activities of Daily Living for dementia in community-dwelling older adults

BACKGROUND

many people living with dementia remain underdiagnosed and unrecognised. Screening strategies are important for early detection.

OBJECTIVE

to examine whether the Lawton's Instrumental Activities of Daily Living (IADL) scale, compared with other cognitive screening tools-the Mini-Mental State Examination (MMSE), and the Ascertain Dementia 8-item Informant Questionnaire (AD8)-can identify older (≥ 65 years) adults with dementia.

DESIGN

population-based cross-sectional observational study.

SETTING

all 19 counties in Taiwan.

PARTICIPANTS

community-dwelling older adults (n = 10,340; mean age 74.87 ± 6.03).

METHODS

all participants underwent a structured in-person interview. Dementia was identified using National Institute on Aging-Alzheimer's Association core clinical criteria for all-cause dementia. Receiver operator characteristic curves were used to determine the discriminant abilities of the IADL scale, MMSE and AD8 to differentiate participants with and without dementia.

RESULTS

we identified 917 (8.9%) participants with dementia, and 9,423 (91.1%) participants without. The discriminant abilities of the MMSE, AD8 and IADL scale (cutoff score: 6/7; area under curve = 0.925; sensitivity = 89%; specificity = 81%; positive likelihood ratio = 4.75; accuracy = 0.82) were comparable. Combining IADL with AD8 scores significantly improved overall accuracy: specificity = 93%; positive likelihood ratio = 11.74; accuracy = 0.92.

CONCLUSIONS

our findings support using IADL scale to screen older community-dwelling residents for dementia: it has discriminant power comparable to that of the AD8 and MMSE. Combining the IADL and the AD8 improves specificity.

Early Functional Limitations in Cognitively Normal Older Adults Predict Diagnostic Conversion to Mild Cognitive Impairment

OBJECTIVES

To examine whether specific types of early functional limitations in cognitively normal older adults are associated with subsequent development of mild cognitive impairment (MCI), as well as the relative predictive value of self versus informant report in predicting diagnostic conversion to MCI.

DESIGN

As a part of a longitudinal study design, participants underwent baseline and annual multidisciplinary clinical evaluations, including a physical and neurological examination, imaging, laboratory work, and neuropsychological testing.

SETTING

Data used in this study were collected as part of longitudinal research at the University of California, Davis Alzheimer's Disease Center.

PARTICIPANTS

Individuals diagnosed as having normal cognition at study baseline who had an informant who could complete informant-based ratings and at least one follow-up visit (N = 324).

MEASUREMENTS

Participants and informants each completed the Everyday Cognition Scale (ECog), an instrument designed to measure everyday function in six cognitively relevant domains.

RESULTS

Self- and informant-reported functional limitations on the ECog were associated with significantly greater risk of diagnostic conversion to MCI (informant: hazard ratio (HR) = 2.0, 95% confidence interval (CI) = 1.3-3.2, P = .002), with self-report having a slightly higher hazard (HR = 2.3, 95% CI = 1.4-3.6, P < .001). When controlling for baseline cognitive abilities, the effect remained significant for self- and informant-reported functional limitations.

CONCLUSION

Deficits in everyday memory and executive function domains were the strongest predictors of diagnostic conversion to MCI. Detection of early functional limitations may be clinically useful in assessing the future risk of developing cognitive impairment in cognitively normal older adults.

Functional Disability in Mild Cognitive Impairment: A Systematic Review and Meta-Analysis

Accumulating evidence suggests that the pre-dementia syndrome mild cognitive impairment (MCI) is characterized by decrements in instrumental activities of daily living (IADL). The current review was a quantitative synthesis of the available literature to objectively characterize IADL disability in MCI while clarifying inconsistencies in findings across studies. It was hypothesized that individuals with MCI would display significantly greater functional impairment relative to cognitively intact controls. Candidate moderators specified a priori included functional assessment approach, MCI subtype, depressive symptoms, and language conducted. Online databases (PubMed/MEDLINE and PsycINFO) and reference lists were searched to identify peer-reviewed publications assessing IADL in MCI compared to normal aging. A total of 151 effect sizes derived from 106 studies met inclusionary criteria (N = 62,260). Random effects models yielded a large overall summary effect size (Hedges' g = 0.76, 95 % confidence interval: 0.68 - 0.83, p < .001) confirmed in multi-level analyses adjusted for nesting of effect sizes within studies (g = 0.78, 95 % confidence interval: 0.69 - 0.87). Functional assessment strategy and MCI subtype were significant moderators of effect size, whereas depressive symptoms and language were not. Results convincingly demonstrate that MCI is associated with significant difficulties in the performance of complex everyday tasks. It appears that functional decline, like cognitive decline, exists on a continuum from healthy aging to dementia onset. Implications for clinical practice and research priorities are discussed.

Modeling Patterns of Activities using Activity Curves

Pervasive computing offers an unprecedented opportunity to unobtrusively monitor behavior and use the large amount of collected data to perform analysis of activity-based behavioral patterns. In this paper, we introduce the notion of an activity curve, which represents an abstraction of an individual's normal daily routine based on automatically-recognized activities. We propose methods to detect changes in behavioral routines by comparing activity curves and use these changes to analyze the possibility of changes in cognitive or physical health. We demonstrate our model and evaluate our change detection approach using a longitudinal smart home sensor dataset collected from 18 smart homes with older adult residents. Finally, we demonstrate how big data-based pervasive analytics such as activity curve-based change detection can be used to perform functional health assessment. Our evaluation indicates that correlations do exist between behavior and health changes and that these changes can be automatically detected using smart homes, machine learning, and big data-based pervasive analytics.

Validation of the Erlangen Test of Activities of Daily Living in Persons with Mild Dementia or Mild Cognitive Impairment (ETAM)

BACKGROUND

There are currently no valid, fast, and easy-to-administer performance tests that are designed to assess the capacities to perform activities of daily living in persons with mild dementia and mild cognitive impairment (MCI). However, such measures are urgently needed for determining individual support needs as well as the efficacy of interventions. The aim of the present study was therefore to validate the Erlangen Test of Activities of Daily Living in Persons with Mild Dementia and Mild Cognitive Impairment (ETAM), a performance test that is based on the International Classification of Functioning and Health (ICF), which assesses the relevant domains of living in older adults with MCI and mild dementia who live independently.

METHODS

The 10 ICF-based items on the research version of the ETAM were tested in a final sample of 81 persons with MCI or mild dementia. The items were selected for the final version in accordance with 6 criteria: 1) all domains must be represented and have equal weight, 2) all items must load on the same factor, 3) item difficulties and item discriminatory powers, 4) convergent validity (Bayer Activities of Daily Living Scale [B-ADL]) and discriminant validity (Mini Mental State Examination [MMSE], Geriatric Depression Scale 15 [GDS-15]), 5) inter-rater reliabilities of the individual items, 6) as little material as possible. Retest reliability was also examined. Cohen's ds were calculated to determine the magnitudes of the differences in ETAM scores between participants diagnosed with different grades of severity of cognitive impairment.

RESULTS

The final version of the ETAM consists of 6 items that cover the five ICF domains communication, mobility, self-care, domestic life (assessed by two 3-point items), and major life areas (specifically, the economic life sub-category) and load on a single factor. The maximum achievable score is 30 points (6 points per domain). The average administration time was 35 min, 19 of which were needed for pure item performance. The internal consistency was α = .71. The three-week test-retest reliability was r = .78, and the inter-rater reliability was r = .97. The ETAM also provided satisfactory discrimination between healthy individuals and persons with MCI or mild dementia as well as between persons with mild and moderate dementia.

CONCLUSIONS

The 6-item final version of the ETAM shows satisfactory psychometric characteristics and can be administered quickly. It is therefore suitable for use in both clinical practice and research.

Development and validation of a new performance-based measurement of instrumental activities of daily living in Taiwan

BACKGROUND

The performance-based instrumental activities of daily living (IADL) measurement is thought to improve the validity and reliability of conventional tools that rely on proxy reports. The aims of this study were to develop and validate a performance-based measurement of IADL for use in elderly patients with cognitive impairment in Taiwan and other Chinese-speaking communities.

METHODS

Referring to current versions of performance-based IADL, we developed the new Taiwan Performance-Based IADL (TPIADL) measurement to minimize literacy dependency and render it compatible with local culture. Participants performed tasks, including finding a telephone number, calculating the correct amount of change, reading the ingredients on a tin of food, finding food items on a shelf, and reading instructions on a medicine container. The internal consistency and convergent and criteria validity of the TPIADL were examined.

RESULTS

Altogether, 117 elderly subjects were invited to participate in this study, including 39 patients with dementia due to Alzheimer's disease, 29 with amnestic mild cognitive impairment, and 49 without cognitive impairment. The internal consistency of the TPIADL was 0.82. The TPIADL scores were significantly correlated with the Lawton Instrumental Activities of Daily Living Scale (r = 0.76, P < 0.001). The area under the relative operating characteristic curve was 0.90 (95% confidence interval = 0.84-0.97) to differentiate dementia due to Alzheimer's disease and others. The optimal cut-off point for the TPIADL was 6/7, which gives a sensitivity of 84.6% and a specificity of 75.6%.

CONCLUSIONS

The TPIADL is a validated instrument for the measurement of IADL in elderly subjects. It might replace conventional assessment as a valid and easily administered measurement.

Daily Activity Abilities in MCI, Alzheimer's Disease, and Healthy Controls

Mild cognitive impairment (MCI) is a risk state for dementia. The present study assessed daily functioning in MCI individuals (amnestic [aMCI] and nonamnestic [naMCI]) relative to those with Alzheimer's disease (AD) and healthy controls (NC). Twenty AD participants, 14 aMCI, 12 naMCI, and 30 healthy controls were administered the Direct Assessment of Functional Status (DAFS). The AD group performed poorer than all groups on all DAFS subscales. The aMCI group performed poorer than controls on the shopping subtests, while the naMCI group performed poorer than controls on only the free recall shopping. Finally, DAFS subscales discriminated the AD and aMCI groups well, but only recognition shopping discriminated between naMCI and aMCI individuals. These findings suggest that circumscribed ADL deficits distinguish subtypes of MCI and AD.

Analyzing Activity Behavior and Movement in a Naturalistic Environment Using Smart Home Techniques

One of the many services that intelligent systems can provide is the ability to analyze the impact of different medical conditions on daily behavior. In this study, we use smart home and wearable sensors to collect data, while ( n = 84) older adults perform complex activities of daily living. We analyze the data using machine learning techniques and reveal that differences between healthy older adults and adults with Parkinson disease not only exist in their activity patterns, but that these differences can be automatically recognized. Our machine learning classifiers reach an accuracy of 0.97 with an area under the ROC curve value of 0.97 in distinguishing these groups. Our permutation-based testing confirms that the sensor-based differences between these groups are statistically significant.

Regional cortical thinning and cerebrospinal biomarkers predict worsening daily functioning across the Alzheimer's disease spectrum

BACKGROUND

Impairment in instrumental activities of daily living (IADL) heralds the transition from mild cognitive impairment (MCI) to dementia and is a major source of burden for both the patient and caregiver.

OBJECTIVE

To investigate the relationship between IADL and regional cortical thinning and cerebrospinal fluid (CSF) Alzheimer's disease (AD) biomarkers cross-sectionally and longitudinally in clinically normal (CN) elderly, MCI, and mild AD dementia subjects.

METHODS

Two hundred and twenty nine CN, 395 MCI, and 188 AD dementia subjects participating in the Alzheimer's Disease Neuroimaging Initiative underwent baseline magnetic resonance imaging, baseline lumbar puncture, and clinical assessments, including the Functional Activities Questionnaire used to measure IADL, every 6 to 12 months up to 3 years. General linear regression and mixed effects models were employed.

RESULTS

IADL impairment was associated with the interactions between lower inferior temporal cortical thickness and diagnosis (p < 0.0001), greater lateral occipital cortical thickness and diagnosis (p < 0.0001), and greater amyloid-β 1-42 (Aβ1-42) and diagnosis (p = 0.0002) at baseline (driven by AD dementia). Lower baseline supramarginal (p = 0.02) and inferior temporal (p = 0.05) cortical thickness, lower Aβ1-42 (p < 0.0001), and greater total tau (t-tau) (p = 0.02) were associated with greater rate of IADL impairment over time.

CONCLUSIONS

Temporal atrophy is associated with IADL impairment in mild AD dementia at baseline, while baseline parietal and temporal atrophy, lower CSF Aβ1-42, and greater t-tau predict worsening IADL impairment over time across the AD spectrum. These results emphasize the importance of assessing IADL at the stage of MCI and even at the transition from CN to MCI.

The Potential Utility of Eye Movements in the Detection and Characterization of Everyday Functional Difficulties in Mild Cognitive Impairment

Mild cognitive impairment (MCI) refers to the intermediate period between the typical cognitive decline of normal aging and more severe decline associated with dementia, and it is associated with greater risk for progression to dementia. Research has suggested that functional abilities are compromised in MCI, but the degree of impairment and underlying mechanisms remain poorly understood. The development of sensitive measures to assess subtle functional decline poses a major challenge for characterizing functional limitations in MCI. Eye-tracking methodology has been used to describe visual processes in everyday, naturalistic action among healthy older adults as well as several case studies of severely impaired individuals, and it has successfully differentiated healthy older adults from those with MCI on specific visual tasks. These studies highlight the promise of eye-tracking technology as a method to characterize subtle functional decline in MCI. However, to date no studies have examined visual behaviors during completion of naturalistic tasks in MCI. This review describes the current understanding of functional ability in MCI, summarizes findings of eye-tracking studies in healthy individuals, severe impairment, and MCI, and presents future research directions to aid with early identification and prevention of functional decline in disorders of aging.

Mild cognitive impairment and deficits in instrumental activities of daily living: a systematic review

INTRODUCTION

There is a growing body of evidence that subtle deficits in instrumental activities of daily living (IADL) may be present in mild cognitive impairment (MCI). However, it is not clear if there are IADL domains that are consistently affected across patients with MCI. In this systematic review, therefore, we aimed to summarize research results regarding the performance of MCI patients in specific IADL (sub)domains compared with persons who are cognitively normal and/or patients with dementia.

METHODS

The databases PsycINFO, PubMed and Web of Science were searched for relevant literature in December 2013. Publications from 1999 onward were considered for inclusion. Altogether, 497 articles were retrieved. Reference lists of selected articles were searched for potentially relevant articles. After screening the abstracts of these 497 articles, 37 articles were included in this review.

RESULTS

In 35 studies, IADL deficits (such as problems with medication intake, telephone use, keeping appointments, finding things at home and using everyday technology) were documented in patients with MCI. Financial capacity in patients with MCI was affected in the majority of studies. Effect sizes for group differences between patients with MCI and healthy controls were predominantly moderate to large. Performance-based instruments showed slight advantages (in terms of effect sizes) in detecting group differences in IADL functioning between patients with MCI, patients with Alzheimer's disease and healthy controls.

CONCLUSION

IADL requiring higher neuropsychological functioning seem to be most severely affected in patients with MCI. A reliable identification of such deficits is necessary, as patients with MCI with IADL deficits seem to have a higher risk of converting to dementia than patients with MCI without IADL deficits. The use of assessment tools specifically designed and validated for patients with MCI is therefore strongly recommended. Furthermore, the development of performance-based assessment instruments should be intensified, as they allow a valid and reliable assessment of subtle IADL deficits in MCI, even if a proxy is not available. Another important point to consider when designing new scales is the inclusion of technology-associated IADL. Novel instruments for clinical practice should be time-efficient and easy to administer.

Development and psychometric properties of the instrumental activities of daily living: compensation scale

The Instrumental Activities of Daily Living - Compensation (IADL-C) scale was developed to capture early functional difficulties and to quantify compensatory strategy use that may mitigate functional decline in the aging population. The IADL-C was validated in a sample of cognitively healthy older adults (N=184) and individuals with mild cognitive impairment (MCI; N=92) and dementia (N=24). Factor analysis and Rasch item analysis led to the 27-item IADL-C informant questionnaire with four functional domain subscales (money and self-management, home daily living, travel and event memory, and social skills). The subscales demonstrated good internal consistency (Rasch reliability 0.80 to 0.93) and test-retest reliability (Spearman coefficients 0.70 to 0.91). The IADL-C total score and subscales showed convergent validity with other IADL measures, discriminant validity with psychosocial measures, and the ability to discriminate between diagnostic groups. The money and self management subscale showed notable difficulties for individuals with MCI, whereas difficulties with home daily living became more prominent for dementia participants. Compensatory strategy use increased in the MCI group and decreased in the dementia group.

Factors associated with cognition recovery among elders with mild cognitive impairment in Korea

BACKGROUND

Of elders with mild cognitive impairment, around half recover their cognitive function at some point in time. However, very little is known about the factors that influence their cognitive change towards recovery.

AIM

This study evaluated the role of depression, instrumental activity of daily living and sleep quality as they affect cognition recovery among community-dwelling elders.

METHODS

The study follows a longitudinal comparative research design using secondary data analysis. Community-dwelling elders with mild cognitive impairment were assessed twice with a 1-year interval to assess their levels of cognition. Adult participants were drawn from those who visited a community health centre, were aged 65 or over and who were assessed as having MCI.

RESULTS

Those with mild cognitive impairment when compared with the normal cognition group were more likely to be younger, have more education, living with their spouses and had better cognitive function at baseline assessment than other participants. Predictors for cognitive recovery among elders with mild cognitive impairment were age, depression and cognitive function at baseline assessment.

LIMITATIONS

Participants included only those who visit a community health centre in an urban area of Korea, so the findings may not be applicable to other elders with less mobility or who live in rural areas.

IMPLICATIONS FOR NURSING AND HEALTH POLICY

With the understanding that cognitive function and depression predict the recovery of mild cognitive function, nurses might be able to identify and target those older adults who are likely to achieve recovery of cognitive function. Additionally, health policy options, as suggested by the study as having the potential to improve mild cognitive impairment recovery, could include public education strategies.

Cognitive correlates of functional abilities in individuals with mild cognitive impairment: comparison of questionnaire, direct observation, and performance-based measures

The relationship between, and the cognitive correlates of, several proxy measures of functional status were studied in a population with mild cognitive impairment (MCI). Participants were 51 individuals diagnosed with MCI and 51 cognitively healthy older adults (OA). Participants completed performance-based functional status tests and standardized neuropsychological tests, and performed eight activities of daily living (e.g., watered plants, filled medication dispenser) while under direct observation in a campus apartment. An informant interview about everyday functioning was also conducted. Compared to the OA control group, the MCI group performed more poorly on all proxy measures of everyday functioning. The informant report of instrumental activities of daily living (IADL) did not correlate with the two performance-based measures; however, both the informant-report IADL and the performance-based everyday problem-solving test correlated with the direct observation measure. After controlling for age and education, cognitive predictors did not explain a significant amount of variance in the performance-based measures; however, performance on a delayed memory task was a unique predictor for the informant-report IADL, and processing speed predicted unique variance for the direct observation score. These findings indicate that differing methods for evaluating functional status are not assessing completely overlapping aspects of everyday functioning in the MCI population.

A hierarchy of predictors for dementia-free survival in old-age: results of the AgeCoDe study

OBJECTIVE

Progression from cognitive impairment (CI) to dementia is predicted by several factors, but their relative importance and interaction are unclear.

METHOD

We investigated numerous such factors in the AgeCoDe study, a longitudinal study of general practice patients aged 75+. We used recursive partitioning analysis (RPA) to identify hierarchical patterns of baseline covariates that predicted dementia-free survival.

RESULTS

Among 784 non-demented patients with CI, 157 (20.0%) developed dementia over a follow-up interval of 4.5 years. RPA showed that more severe cognitive compromise, revealed by a Mini-Mental State Examination (MMSE) score < 27.47, was the strongest predictor of imminent dementia. Dementia-free survival time was shortest (mean 2.4 years) in such low-scoring patients who also had impaired instrumental activities of daily living (iADL) and subjective memory impairment with related worry (SMI-w). Patients with identical characteristics but without SMI-w had an estimated mean dementia-free survival time of 3.8 years, which was still shorter than in patients who had subthreshold MMSE scores but intact iADL (4.2-5.2 years).

CONCLUSION

Hierarchical patterns of readily available covariates can predict dementia-free survival in older general practice patients with CI. Although less widely appreciated than other variables, iADL impairment appears to be an especially noteworthy predictor of progression to dementia.

Regional fluorodeoxyglucose metabolism and instrumental activities of daily living across the Alzheimer's disease spectrum

BACKGROUND

Impairment in instrumental activities of daily living (IADL) begins as individuals with amnestic mild cognitive impairment (MCI) transition to Alzheimer's disease (AD) dementia. IADL impairment in AD dementia has been associated with inferior parietal, inferior temporal, and superior occipital hypometabolism using 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET).

OBJECTIVE

To investigate the relationship between regional FDG metabolism and IADL in clinically normal (CN) elderly, MCI, and mild AD dementia subjects cross-sectionally and longitudinally.

METHODS

One hundred and four CN, 203 MCI, and 95 AD dementia subjects from the Alzheimer's Disease Neuroimaging Initiative underwent clinical assessments every 6 to 12 months for up to three years and baseline FDG PET. The subjective, informant-based Functional Activities Questionnaire was used to assess IADL. General linear models and mixed effects models were used, covarying for demographics, cognition, and behavior.

RESULTS

The cross-sectional analysis revealed middle frontal and orbitofrontal hypometabolism were significantly associated with greater IADL impairment. Additionally, the interaction of diagnosis with posterior cingulate and with parahippocampal hypometabolism showed a greater decline in IADL performance as metabolism decreased for the AD dementia relative to the MCI group, and the MCI group relative to the CN group. The longitudinal analysis showed that baseline middle frontal and posterior cingulate hypometabolism were significantly associated with greater rate of increase in IADL impairment over time.

CONCLUSION

These results suggest that regional synaptic dysfunction, including the Alzheimer-typical medial parietal and less typical frontal regions, relates to daily functioning decline at baseline and over time across the early AD spectrum.

Impairment in instrumental activities of daily living with high cognitive demand is an early marker of mild cognitive impairment: the Sydney memory and ageing study

BACKGROUND

Criteria for mild cognitive impairment (MCI) consider impairment in instrumental activities of daily living (IADL) as exclusionary, but cross-sectional studies suggest that some high-level functional deficits are present in MCI. This longitudinal study examines informant-rated IADL in MCI, compared with cognitively normal (CN) older individuals, and explores whether functional abilities, particularly those with high cognitive demand, are predictors of MCI and dementia over a 2-year period in individuals who were CN at baseline.

METHOD

A sample of 602 non-demented community dwelling individuals (375 CN and 227 with MCI) aged 70-90 years underwent baseline and 24-month assessments that included cognitive and medical assessments and an interview with a knowledgeable informant on functional abilities with the Bayer Activities of Daily Living Scale.

RESULTS

Significantly more deficits in informant-reported IADL with high cognitive demand were present in MCI compared with CN individuals at baseline and 2-year follow-up. Functional ability in CN individuals at baseline, particularly in activities with high cognitive demand, predicted MCI and dementia at follow-up. Difficulties with highly cognitively demanding activities specifically predicted amnestic MCI but not non-amnestic MCI whereas those with low cognitive demand did not predict MCI or dementia. Age, depressive symptoms, cardiovascular risk factors and the sex of the informant did not contribute to the prediction.

CONCLUSIONS

IADL are affected in individuals with MCI, and IADL with a high cognitive demand show impairment predating the diagnosis of MCI. Subtle cognitive impairment is therefore likely to be a major hidden burden in society.

Emotion recognition in mild cognitive impairment: relationship to psychosocial disability and caregiver burden

BACKGROUND

Impaired emotion recognition in dementia is associated with increased patient agitation, behavior management difficulties, and caregiver burden. Emerging evidence supports the presence of very early emotion recognition difficulties in mild cognitive impairment (MCI); however, the relationship between these impairments and psychosocial measures is not yet explored.

METHODS

Emotion recognition abilities of 27 patients with nonamnestic MCI (naMCI), 29 patients with amnestic MCI (aMCI), and 22 control participants were assessed. Self-report measures assessed patient functional disability, while informants rated the degree of burden they experienced.

RESULTS

Difficulties in recognizing anger was evident in the amnestic subtype. Although both the patient groups reported greater social functioning disability, compared with the controls, a relationship between social dysfunction and anger recognition was evident only for patients with naMCI. A significant association was found between burden and anger recognition in patients with aMCI.

CONCLUSIONS

Impaired emotion recognition abilities impact MCI subtypes differentially. Interventions targeted at patients with MCI, and caregivers are warranted.

Predictors of institutionalisation in incident dementia--results of the German Study on Ageing, Cognition and Dementia in Primary Care Patients (AgeCoDe study)

BACKGROUND/AIMS

In the past few decades, a number of studies investigated risk factors of nursing home placement (NHP) in dementia patients. The aim of the study was to investigate risk factors of NHP in incident dementia cases, considering characteristics at the time of the dementia diagnosis.

METHODS

254 incident dementia cases from a German general practice sample aged 75 years and older which were assessed every 1.5 years over 4 waves were included. A Cox proportional hazard regression model was used to determine predictors of NHP. Kaplan-Meier survival curves were used to evaluate the time until NHP.

RESULTS

Of the 254 incident dementia cases, 77 (30%) were institutionalised over the study course. The mean time until NHP was 4.1 years. Significant characteristics of NHP at the time of the dementia diagnosis were marital status (being single or widowed), higher severity of cognitive impairment and mobility impairment.

CONCLUSION

Marital status seems to play a decisive role in NHP. Early initiation of support of sufferers may ensure remaining in the familiar surroundings as long as possible.

Prediction of incident dementia: impact of impairment in instrumental activities of daily living and mild cognitive impairment-results from the German study on ageing, cognition, and dementia in primary care patients

OBJECTIVES

There is an increasing call for a stronger consideration of impairment in instrumental activities of daily living (IADL) in the diagnostic criteria of Mild Cognitive Impairment (MCI) to improve the prediction of dementia. Thus, the aim of the study was to determine the predictive capability of MCI and IADL impairment for incident dementia.

DESIGN

Longitudinal cohort study with four assessments at 1.5-year intervals over a period of 4.5 years.

SETTING

: Primary care medical record registry sample.

PARTICIPANTS

As part of the German Study on Ageing, Cognition, and Dementia in Primary Care Patients, a sample of 3,327 patients from general practitioners, aged 75 years and older, was assessed.

MEASUREMENTS

The predictive capability of MCI and IADL impairment for incident dementia was analysed using receiver operating characteristics, Kaplan-Meier survival analyses, and Cox proportional hazards models.

RESULTS

MCI and IADL impairment were found to be significantly associated with higher conversion to, shorter time to, and better predictive power for future dementia. Regarding IADL, a significant impact was particularly found for impairment in responsibility for one's own medication, shopping, and housekeeping, and in the ability to use public transport.

CONCLUSIONS

Combining MCI with IADL impairment significantly improves the prediction of future dementia. Even though information on a set of risk factors is required to achieve a predictive accuracy for dementia in subjects with MCI being clinically useful, IADL impairment should be a very important element of such a risk factor set.

Activities of daily living: where do they fit in the diagnosis of Alzheimer's disease?

Impairment in activities of daily living (ADL) accompanies cognitive and behavioral symptoms in Alzheimer's disease (AD). Conventionally, ADL impairment has been relegated to the stage of dementia, but instrumental ADL impairment has been shown to occur earlier at the stage of mild cognitive impairment (MCI). There are many subjective and performance-based instrumental ADL scales, some of which are useful in distinguishing between MCI and AD dementia, and even between MCI and clinically normal elderly individuals. These scales have been associated with amyloid and neurodegeneration biomarkers of AD. Clinically normal elderly individuals who have a positive AD biomarker are thought to be at the preclinical stage of AD. Scales of more complex ADL are needed to better capture individuals with preclinical AD before they start to progress to MCI.

Correlation between instrumental activities of daily living and white matter hyperintensities in amnestic mild cognitive impairment: results of a cross-sectional study

Although some studies have supported the association between white matter hyperintensities (WMH) and cognitive impairment, whether WMH are associated with the impairments in instrumental activities of daily living (IADLs) remains unknown. This cross-sectional study investigated differences in basic ADLs and IADLs among different severity of WMH in a large, well-defined registry of patients with amnestic mild cognitive impairment (aMCI). 1,514 patients with aMCI were divided into three groups according to the degree of WMH (1,026 mild, 393 moderate, and 95 severe). We compared the total IADL scores and analyzed the prevalence of the impairment for each IADL item for each group. The severity of WMH was associated with the impairments in IADLs. Among 15 Seoul IADL items, "using public transportation", "going out (short distance)", "grooming" and "participating in leisure activities/hobbies" showed greater positive association with the severity of WMH. WMH in patients with aMCI were associated with the impairments in IADLs but not in basic ADLs. These findings are likely to be more obvious with respect to using public transportation, going out (short distances), shopping, grooming and participating in leisure activities/hobbies.