Structural Correlates of Overt Sentence Reading in Mild Cognitive Impairment and Mild-to-Moderate Alzheimer's Disease.

BACKGROUND: Overt sentence reading in mild cognitive impairment (MCI) and mild-tomoderate Alzheimer's disease (AD) has been associated with slowness of speech, characterized by a higher number of pauses, shorter speech units and slower speech rate and attributed to reduced working memory/ attention and language capacity. OBJECTIVE: This preliminary case-control study investigates whether the temporal organization of speech is associated with the volume of brain regions involved in overt sentence reading and explores the discriminative ability of temporal speech parameters and standard volumetric MRI measures for the classification of MCI and AD. METHODS: Individuals with MCI, mild-to-moderate AD, and healthy controls (HC) had a structural MRI scan and read aloud sentences varying in cognitive-linguistic demand (length). The association between speech features and regional brain volumes was examined by linear mixed-effect modeling. Genetic programming was used to explore the discriminative ability of temporal and MRI features. RESULTS: Longer sentences, slower speech rate, and a higher number of pauses and shorter interpausal units were associated with reduced volumes of the reading network. Speech-based classifiers performed similarly to the MRI-based classifiers for MCI-HC (67% vs. 68%) and slightly better for AD-HC (80% vs. 64%) and AD-MCI (82% vs. 59%). Adding the speech features to the MRI features slightly improved the performance of MRI-based classification for AD-HC and MCI-HC but not HC-MCI. CONCLUSION: The temporal organization of speech in overt sentence reading reflects underlying volume reductions. It may represent a sensitive marker for early assessment of structural changes and cognitive- linguistic deficits associated with healthy aging, MCI, and AD.

Cognitive and Structural Correlates of Conversational Speech Timing in Mild Cognitive Impairment and Mild-to-Moderate Alzheimer's Disease: Relevance for Early Detection Approaches.

Background: Increasing efforts have focused on the establishment of novel biomarkers for the early detection of Alzheimer's disease (AD) and prediction of Mild Cognitive Impairment (MCI)-to-AD conversion. Behavioral changes over the course of healthy ageing, at disease onset and during disease progression, have been recently put forward as promising markers for the detection of MCI and AD. The present study examines whether the temporal characteristics of speech in a collaborative referencing task are associated with cognitive function and the volumes of brain regions involved in speech production and known to be reduced in MCI and AD pathology. We then explore the discriminative ability of the temporal speech measures for the classification of MCI and AD. Method: Individuals with MCI, mild-to-moderate AD and healthy controls (HCs) underwent a structural MRI scan and a battery of neuropsychological tests. They also engaged in a collaborative referencing task with a caregiver. The associations between the conversational speech timing features, cognitive function (domain-specific) and regional brain volumes were examined by means of linear mixed-effect modeling. Genetic programming was used to explore the discriminative ability of the conversational speech features. Results: MCI and mild-to-moderate AD are characterized by a general slowness of speech, attributed to slower speech rate and slower turn-taking in conversational settings. The speech characteristics appear to be reflective of episodic, lexico-semantic, executive functioning and visuospatial deficits and underlying volume reductions in frontal, temporal and cerebellar areas. Conclusion: The implementation of conversational speech timing-based technologies in clinical and community settings may provide additional markers for the early detection of cognitive deficits and structural changes associated with MCI and AD.

Changes in Speech Chunking in Reading Aloud is a Marker of Mild Cognitive Impairment and Mild-to-Moderate Alzheimer's Disease.

BACKGROUND: Speech and Language Impairments, generally attributed to lexico-semantic deficits, have been documented in Mild Cognitive Impairment (MCI) and Alzheimer's disease (AD). This study investigates the temporal organisation of speech (reflective of speech production planning) in reading aloud in relation to cognitive impairment, particularly working memory and attention deficits in MCI and AD. The discriminative ability of temporal features extracted from a newly designed read speech task is also evaluated for the detection of MCI and AD. METHOD: Sixteen patients with MCI, eighteen patients with mild-to-moderate AD and thirty-six healthy controls (HC) underwent a battery of neuropsychological tests and read a set of sentences varying in cognitive load, probed by manipulating sentence length and syntactic complexity. RESULTS: Our results show that Mild-to-Moderate AD is associated with a general slowness of speech, attributed to a higher number of speech chunks, silent pauses and dysfluences, and slower speech and articulation rates. Speech chunking in the context of high cognitive-linguistic demand appears to be an informative marker of MCI, specifically related to early deficits in working memory and attention. In addition, Linear Discriminant Analysis shows the ROC AUCs (Areas Under the Receiver Operating Characteristic Curves) of identifying MCI vs. HC, MCI vs. AD and AD vs. HC using these speech characteristics are 0.75, 0.90 and 0.94 respectively. CONCLUSION: The implementation of connected speech-based technologies in clinical and community settings may provide additional information for the early detection of MCI and AD.

Association of an Asthma Improvement Collaborative With Health Care Utilization in Medicaid-Insured Pediatric Patients in an Urban Community.

Importance: Asthma is the most common chronic condition of childhood. Hospitalizations and emergency department (ED) visits for asthma are more frequently experienced by minority children and adolescents and those with low socioeconomic status. Objective: To reduce asthma-related hospitalizations and ED visits for Medicaid-insured pediatric patients residing in Hamilton County, Ohio. Design, Setting, and Participants: From January 1, 2010, through December 31, 2015, a multidisciplinary team used quality-improvement methods and the chronic care model to conduct interventions in inpatient, outpatient, and community settings in a large, urban academic pediatric hospital in Hamilton County, Ohio. Children and adolescents aged 2 to 17 years who resided in Hamilton County, had a diagnosis of asthma, and were Medicaid insured were studied. Interventions: Interventions were implemented in 3 phases: hospital-based inpatient care redesign, outpatient-based care enhancements, and community-based supports. Plan-do-study-act cycles allowed for small-scale implementation of change concepts and rapid evaluation of how such tests affected processes and outcomes of interest. Main Outcomes and Measures: The study measured asthma-related hospitalizations and ED visits per 10 000 Medicaid-insured pediatric patients. Data were measured monthly on a rolling 12-month mean basis. Data from multiple previous years were used to establish a baseline. Data were tracked with annotated control charts and with interrupted time-series analysis. Results: Of the estimated 36 000 children and adolescents with asthma in Hamilton County (approximately 13 000 of whom are Medicaid insured and 6000 of whom are cared for in Cincinnati Children's Hospital primary care practices), asthma-related hospitalizations decreased from 8.1 (95% CI, 7.7-8.5) to 4.7 (95% CI, 4.3-5.1) per 10 000 Medicaid patients per month by June 30, 2014, a 41.8% (95% CI, 41.7%-42.0%) relative reduction. Emergency department visits decreased from 21.5 (95% CI, 20.6-22.3) to 12.4 (95% CI, 11.5-13.2) per 10 000 Medicaid patients per month by June 30, 2014, a 42.4% (95% CI, 42.2%-42.6%) relative reduction. Improvements were sustained for the subsequent 12 months. The proportion of patients who were rehospitalized or had a return ED visit for asthma within 30 days of an index hospitalization was reduced from 12% to 7%. The proportion of patients with documented well-controlled asthma in this study's primary care population increased from 48% to 54%. Conclusions and Relevance: An integrated, multilevel approach focused on enhancing availability and accessibility of treatments, removing barriers to adherence, mitigating multidomain risks, augmenting self-management, and creating a collaborative relationship between the family and the health care system was associated with improved asthma outcomes for a population of Medicaid-insured pediatric patients. Similar models used in accountable care organizations or across patient panels and with other chronic conditions could be feasible and warrant evaluation.

The clinical utility of naturalistic action test in differentiating mild cognitive impairment from early dementia in memory clinic.

OBJECTIVE: This study aimed to examine the validity of the Naturalistic Action Test in differentiating Mild Cognitive Impairment from early dementia compared to clinical diagnosis and ascertain Naturalistic Action Test cut-off points. METHODS: This was a cross-sectional study of 70 consecutive patients diagnosed with Mild Cognitive Impairment attending the memory clinic in St James's Hospital, Dublin, Ireland. Patients with a diagnosis of Mild Cognitive Impairment who attended for routine annual assessment were asked to participate in the study. The Naturalistic Action Test was carried out after the patient had completed their routine assessment in the clinic. RESULTS: The Area under the Curve, AUC ± SE was 0.808 ± 0.058, p < 0.001 with 95% CI (0.695-0.922). There was concordance in 40 and discrepancy in 30 patients between the NAT and the gold standard consensus diagnosis (PPV 38%, NPV 96%, sensitivity 94%, specificity 46% and accuracy 59%) using cut-off point of ≥14 for normal function on Naturalistic Action Test. The difference was not related to age, sex, level of education or informant. Using the Youden index, we determined a Naturalistic Action Test cut-off score of ≥11 for Mild Cognitive Impairment in our study (PPV 50%, NPV 91%, sensitivity 78%, specificity 73% and accuracy of 74%). There was discrepancy in 18 patients using the new cut-off point (≥11 for Mild Cognitive Impairment vs ≤10 for dementia). CONCLUSION: The Naturalistic Action Test is a useful tool that can increase diagnostic accuracy in differentiating Mild Cognitive Impairment from early dementia.

Frailty: a costly phenomenon in caring for elders with cognitive impairment.

OBJECTIVES: Dementia draws on a variety of public and private resources. There is increasing pressure to define the cost components in this area to improve resource allocation and accountability. The aim of this study was to characterize frailty in a group of cognitively impaired community-dwelling elders and evaluate its relationship with cost and resource utilization. METHODS: We assessed a cross-sectional, convenient sample of 115 cognitively impaired patients of age >55 years who attended the National Memory Clinic in St James' University Hospital, a Trinity College-affiliated hospital in Dublin, Ireland. Participants had a clinical diagnosis of possible Alzheimer's disease or mild cognitive impairment. Frailty was measured using the biological syndrome model. Formal health and social care costs and daily informal caregiving costs were collected and the total costs of care estimated by applying the appropriate unit cost estimate for each resource activity. Stepwise regression models were constructed to establish the factors associated with increased care costs. RESULTS: Patient dependence, frailty and number of co-morbid illnesses explained 43.3% of the variance in observed daily informal care costs in dementia and cognitively impaired patients. Dependence was the sole factor retained in an optimal model explaining 19% of the variance in formal health and social care costs. CONCLUSION: Frailty retained a strong association with daily informal care costs even in the context of other known risk factors for increasing care costs. Interventions that reduce frailty as well as patient dependence on others may be associated with cost savings.

The relationship between increased body mass index and frailty on falls in community dwelling older adults.

BACKGROUND: The global population is becoming older and more overweight. The inter-relationship between frailty and falls is often seen in the older adult and is associated with poor health outcomes. Little is known about this relationship for those with excess body mass. This study aimed to assess the relationships between BMI, frailty and falls. METHODS: Frailty, body mass index, clinical and demographic characteristics were assessed at baseline for 606 community dwelling adults aged 60 years and older. Falls were assessed prospectively with a semi-structured telephone interview two years later. RESULTS: An increase in BMI contributed significantly to the identification of frail (Odds Ratio: 4.4; 95% Confidence Interval: 1.4, 13.6) older adults. A total of 346 falls by 148 participants were reported at follow up. Those with an increased BMI were significantly less likely to have experienced a fall between baseline and follow up assessments (p = 0.03). Despite these opposing trends a BMI greater than or equal to 30.0 kg.m2 did not alter the relationship between falls and frailty for the current cohort. CONCLUSIONS: This is the first study to assess the falls-frailty relationship for those with an increased BMI. Obesity was found to be protective against falling but not specifically in frail older adults.

Quantitative falls risk estimation through multi-sensor assessment of standing balance.

Falls are the most common cause of injury and hospitalization and one of the principal causes of death and disability in older adults worldwide. Measures of postural stability have been associated with the incidence of falls in older adults. The aim of this study was to develop a model that accurately classifies fallers and non-fallers using novel multi-sensor quantitative balance metrics that can be easily deployed into a home or clinic setting. We compared the classification accuracy of our model with an established method for falls risk assessment, the Berg balance scale. Data were acquired using two sensor modalities--a pressure sensitive platform sensor and a body-worn inertial sensor, mounted on the lower back--from 120 community dwelling older adults (65 with a history of falls, 55 without, mean age 73.7 ± 5.8 years, 63 female) while performing a number of standing balance tasks in a geriatric research clinic. Results obtained using a support vector machine yielded a mean classification accuracy of 71.52% (95% CI: 68.82-74.28) in classifying falls history, obtained using one model classifying all data points. Considering male and female participant data separately yielded classification accuracies of 72.80% (95% CI: 68.85-77.17) and 73.33% (95% CI: 69.88-76.81) respectively, leading to a mean classification accuracy of 73.07% in identifying participants with a history of falls. Results compare favourably to those obtained using the Berg balance scale (mean classification accuracy: 59.42% (95% CI: 56.96-61.88)). Results from the present study could lead to a robust method for assessing falls risk in both supervised and unsupervised environments.

Evaluation of falls risk in community-dwelling older adults using body-worn sensors.

BACKGROUND: Falls are the most common cause of injury and hospitalization and one of the principal causes of death and disability in older adults worldwide. This study aimed to determine if a method based on body-worn sensor data can prospectively predict falls in community-dwelling older adults, and to compare its falls prediction performance to two standard methods on the same data set. METHODS: Data were acquired using body-worn sensors, mounted on the left and right shanks, from 226 community-dwelling older adults (mean age 71.5 ± 6.7 years, 164 female) to quantify gait and lower limb movement while performing the 'Timed Up and Go' (TUG) test in a geriatric research clinic. Participants were contacted by telephone 2 years following their initial assessment to determine if they had fallen. These outcome data were used to create statistical models to predict falls. RESULTS: Results obtained through cross-validation yielded a mean classification accuracy of 79.69% (mean 95% CI: 77.09-82.34) in prospectively identifying participants that fell during the follow-up period. Results were significantly (p < 0.0001) more accurate than those obtained for falls risk estimation using two standard measures of falls risk (manually timed TUG and the Berg balance score, which yielded mean classification accuracies of 59.43% (95% CI: 58.07-60.84) and 64.30% (95% CI: 62.56-66.09), respectively). CONCLUSION: Results suggest that the quantification of movement during the TUG test using body-worn sensors could lead to a robust method for assessing future falls risk.

Frailty and quality of life for people with Alzheimer's dementia and mild cognitive impairment.

BACKGROUND: Our aim was to investigate the relationship between frailty and health-related quality of life (HR-QOL) in cognitively impaired elderly individuals. METHODS: A cross-sectional observational study of a convenience sample of 115 patients with a diagnosis of Alzheimer's dementia or mild cognitive impairment. Frailty was measured using the biological syndrome model and HR-QOL was measured using the DEMQOL-Proxy. Regression models were constructed to establish the factors associated with HR-QOL. RESULTS: Frailty and neuropsychiatric symptoms were associated with HR-QOL, with Mini-Mental State Examination (MMSE) scores ≥21 (P = .037, P ≤ .001, and R (2) = .362). Functional limitation was associated with HR-QOL, with MMSE scores ≤20 (P = .017 and R (2) = .377). CONCLUSION: Frailty and neuropsychiatric symptoms were the determinants of HR-QOL in the earlier stages of cognitive impairment. Functional limitation predicted HR-QOL in the later stages of cognitive impairment. Frailty may represent a novel modifiable target in early dementia to improve HR-QOL for patients.

Taking balance measurement out of the laboratory and into the home: discriminatory capability of novel centre of pressure measurement in fallers and non-fallers.

We investigated three methods for estimating centre of pressure excursions, as measured using a portable pressure sensor matrix, in order to deploy similar technology into the homes of older adults for longitudinal monitoring of postural control and falls risk. We explored the utility of these three methods as markers of falls risk in a cohort of 120 community dwelling older adults with and without a history of falls (65 fallers, 55 non-fallers). A number of standard quantitative balance parameters were derived using each centre of pressure estimation method. Rank sum tests were used to test for significant differences between fallers and non-fallers while intra-class correlation coefficients were also calculated to determine the reliability of each method. A method based on estimating the changes in the magnitude of pressure exerted on the pressure sensor matrix was found to be the most reliable and discriminative. Our future work will implement this method for home-based balance measurement.

Displacement of centre of mass during quiet standing assessed using accelerometry in older fallers and non-fallers.

Postural sway during quiet standing is associated with falls risk in older adults. The aim of this study was to investigate the utility of a range of accelerometer-derived parameters of centre of mass (COM) displacement in identifying older adults at risk of falling. A series of instrumented standing balance trials were performed to investigate postural control in a group of older adults, categorised as fallers or non-fallers. During each trial, participants were asked to stand as still as possible under two conditions: comfortable stance (six repetitions) and semi-tandem stance (three repetitions). A tri-axial accelerometer was secured to the lower back during the trials. Accelerometer data were twice integrated to estimate COM displacement during the trials, with numerical techniques used to reduce integration error. Anterior-posterior (AP) and medial-lateral (ML) sway range, sway length and sway velocity were examined, along with root mean squared (RMS) acceleration. All derived parameters significantly discriminated fallers from non-fallers during both comfortable and semi-tandem stance. Results indicate that these accelerometer-based estimates of COM displacement may improve the discriminative power of quiet standing falls risk assessments, with potential for use in unsupervised balance assessment.

Self-efficacy for managing dementia may protect against burden and depression in Alzheimer's caregivers.

BACKGROUND: Self-efficacy is the belief that one can perform a specific task or behaviour and is a modifiable attribute which has been shown to influence health behaviours. Few studies have examined the relationship between self-efficacy for dementia-related tasks and symptoms of burden and depression in caregivers. METHODS: Eighty four patient/caregiver dyads with Alzheimer's disease were recruited through a memory clinic. Patient function, cognition and neuropsychiatric symptoms were assessed together with caregiver burden, personality, depressive symptoms, coping strategies and self-efficacy for completing tasks related to dementia care. RESULTS: 33% (28) of caregivers reported significant depressive symptoms (CES-D ≥ 10). In multivariate analyses, caregiver burden was predicted by self-efficacy for symptom management, neuroticism, patient function and neuropsychiatric symptoms while caregiver depression was predicted by self-efficacy for symptom management, caregiver educational level, neuroticism, emotion-focused coping, dysfunctional coping and patient function. In patients with moderate to severe impairment (MMSE ≤ 20), self-efficacy for symptom management behaved as a mediator between patient neuropsychiatric symptoms and symptoms of burden and depression in caregivers. CONCLUSIONS: Further longitudinal investigation is warranted to determine if self-efficacy might be usefully considered a target in future interventional studies to alleviate symptoms of burden and depression in Alzheimer's caregivers.

Determinants of the desire to institutionalize in Alzheimer's caregivers.

BACKGROUND: The desire to institutionalize is an important predictor of future institutionalization. Few studies have examined potentially modifiable caregiver characteristics which might be the focus of future interventional strategies. METHODS: A total of 102 patient/caregiver dyads with Alzheimer's disease (n = 84) or mild cognitive impairment were recruited through a memory clinic. Cross-sectional analyses of a range of patients, caregivers, and context of care-related characteristics were conducted. RESULTS: Caregiver desire to institutionalize was significantly associated with a number of potentially modifiable variables including caregiver coping style, self-efficacy, depression, burden, and the presence of an unmet service need. In a multivariate analysis, caregiver burden, depression, and nonspousal status were the only significant independent predictors of caregiver desire to institutionalize in a model which correctly classified 80.4% of caregivers. CONCLUSIONS: Interventions which seek to reduce caregiver desire to institutionalize should adopt a multifactorial approach to reduce symptoms of burden and depression in caregivers.

Dependence and caregiver burden in Alzheimer's disease and mild cognitive impairment.

The dependence scale has been designed to be sensitive to the overall care needs of the patient and is considered distinct from standard measures of functional ability in this regard. Little is known regarding the relationship between patient dependence and caregiver burden. We recruited 100 patients with Alzheimer's disease or mild cognitive impairment and their caregivers through a memory clinic. Patient function, dependence, hours of care, cognition, neuropsychiatric symptoms, and caregiver burden were assessed. Dependence was significantly correlated with caregiver burden. Functional decline and dependence were most predictive of caregiver burden in patients with mild impairment while behavioral symptoms were most predictive in patients with moderate to severe disease. The dependence scale demonstrated good utility as a predictor of caregiver burden. Interventions to reduce caregiver burden should address patient dependence, functional decline, and behavioral symptoms while successful management of the latter becomes more critical with disease progression.