Analysis of cognitive, functional, health service use, and cost trajectories prior to and following memory loss

Preclinical Dementia and Economic Well-Being Trajectories of Racially Diverse Older Adults

ObjectivesThis study examined the magnitude, changes, and racial/ethnic disparities in the economic costs of the 16-year preclinical phase of dementia-a period of cognitive decline without significant impact on daily activities. Methods: The study utilized two dementia algorithms to classify individuals with incident dementia in the Health and Retirement Study. These cases were compared to matched controls in terms of poverty status, labor force participation, and unsecured debts. Results: Older adults classified with dementia were more likely to drop out of the labor force and become poor than similar older adults without dementia. Racial/ethnic disparities in poverty persisted during the preclinical period, with non-Hispanic Black older adults more likely to leave the labor force and Hispanic older adults more likely to have unsecured debt. Discussion: Findings highlight the economic costs during prodromal phase of dementia, emphasizing need for early interventions to reduce financial strain across diverse older adults.

Healthcare utilization prior to a diagnosis of young-onset Alzheimer's disease: a nationwide nested case-control study

OBJECTIVE

Our aim was to identify changes in healthcare utilization prior to a young-onset Alzheimer's disease diagnosis.

METHODS

In a retrospective incidence density matched nested case-control study using national health registers, we examined healthcare utilization for those diagnosed with young-onset Alzheimer's disease in Danish memory clinics during 2016-2018 compared with age- and sex-matched controls. Negative binomial regression analysis produced contact rate ratios.

RESULTS

The study included 1082 young-onset Alzheimer's disease patients and 3246 controls. In the year preceding diagnosis, we found increased contact rate ratios for all types of contacts except physiotherapy. Contact rate ratios for contacts with a general practitioner were significantly increased also > 1-5 and > 5-10 years before diagnosis. The highest contact rate ratios were for psychiatric emergency contacts (8.69, 95% CI 4.29-17.62) ≤ 1 year before diagnosis.

INTERPRETATION

Results demonstrate that young-onset Alzheimer's disease patients have increased healthcare utilization from 5 to 10 years prior to diagnosis. Awareness of specific alterations in health-seeking behaviour may help healthcare professionals provide timely diagnoses.

Development of a machine learning model to predict mild cognitive impairment using natural language processing in the absence of screening

BACKGROUND

Patients and their loved ones often report symptoms or complaints of cognitive decline that clinicians note in free clinical text, but no structured screening or diagnostic data are recorded. These symptoms/complaints may be signals that predict who will go on to be diagnosed with mild cognitive impairment (MCI) and ultimately develop Alzheimer's Disease or related dementias. Our objective was to develop a natural language processing system and prediction model for identification of MCI from clinical text in the absence of screening or other structured diagnostic information.

METHODS

There were two populations of patients: 1794 participants in the Adult Changes in Thought (ACT) study and 2391 patients in the general population of Kaiser Permanente Washington. All individuals had standardized cognitive assessment scores. We excluded patients with a diagnosis of Alzheimer's Disease, Dementia or use of donepezil. We manually annotated 10,391 clinic notes to train the NLP model. Standard Python code was used to extract phrases from notes and map each phrase to a cognitive functioning concept. Concepts derived from the NLP system were used to predict future MCI. The prediction model was trained on the ACT cohort and 60% of the general population cohort with 40% withheld for validation. We used a least absolute shrinkage and selection operator logistic regression approach (LASSO) to fit a prediction model with MCI as the prediction target. Using the predicted case status from the LASSO model and known MCI from standardized scores, we constructed receiver operating curves to measure model performance.

RESULTS

Chart abstraction identified 42 MCI concepts. Prediction model performance in the validation data set was modest with an area under the curve of 0.67. Setting the cutoff for correct classification at 0.60, the classifier yielded sensitivity of 1.7%, specificity of 99.7%, PPV of 70% and NPV of 70.5% in the validation cohort.

DISCUSSION AND CONCLUSION

Although the sensitivity of the machine learning model was poor, negative predictive value was high, an important characteristic of models used for population-based screening. While an AUC of 0.67 is generally considered moderate performance, it is also comparable to several tests that are widely used in clinical practice.

Cost trajectories as a measure of functional resilience after hospitalization in older adults

BACKGROUND

Administrative data sets lack functional measures.

AIM

We examined whether trajectories of cost can be used as a marker of functional recovery after hospitalization.

METHODS

Secondary analysis of the National Health and Aging Trends Study merged with Centers for Medicare and Medicaid Services data. Community-dwelling participants with a first hospitalization occurring after any annual survey were included (N = 937). Monthly total cost trajectories were constructed for the 3 months before and 3 months following hospitalization. Growth mixture models identified groups of patients with similar trajectories. The association of cost classes with five functional outcomes was examined using multivariate models, controlling for pre-hospitalization function and lead time.

RESULTS

Four cost trajectory classes describing common recovery patterns were identified-persistently high, persistently moderate, low-spike-recover, and low variable. Cost class membership was significantly associated with change in Activities of Daily Living (ADL), instrumental ADL, Short Physical Performance Battery, and grip strength (p < 0.005), but not gait speed (p = 0.08). The proportion of patients who maintained or improved SPPB score was 46.8% in the persistently high, 49.2% in the persistently moderate, 52.7% in the low-spike-recover, and 57.2% in the low-variable groups. In models adjusted for known predictors of functional outcome, the magnitude and direction of association was maintained but significance was lost, indicating that cost trajectories' mirror is mediated by predictors of recovery not available in administrative data.

CONCLUSION

Cost trajectories and total costs are associated with functional recovery following hospitalization in older adults. Cost may be useful as a measure of recovery in administrative data.

Racial and ethnic patterns and differences in health care expenditures among Medicare beneficiaries with and without cognitive deficits or Alzheimer's disease and related dementias

BACKGROUND

Numerous studies have documented racial and ethnic differences in the prevalence and incidence of Alzheimer's disease and related dementias (ADRD). Less is known, however, about racial and ethnic differences in health care expenditures among older adults at risk for ADRD (cognitive deficits without ADRD) or with ADRD. In particular, there is limited evidence that racial and ethnic differences in health care expenditures change over the trajectory of ADRD or differ by types of service.

METHODS

We examined racial and ethnic patterns and differences in health care expenditures (total health care expenditures, out-of-pocket expenditures, and six service-specific expenditures) among Medicare beneficiaries without cognitive deficits, those with cognitive deficits without ADRD, and those with ADRD. Using the 1996-2017 Medical Expenditure Panel Survey, we performed multivariable regression models to estimate expenditure differences among racial and ethnic groups without cognitive deficits, those with cognitive deficits without ADRD, and those with ADRD. Models accounted for survey weights and adjusted for various demographic, socioeconomic, and health characteristics.

RESULTS

Black, Asians, and Latinos without cognitive deficits had lower total health care expenditures than whites without cognitive deficits ($10,236, $9497, $9597, and $11,541, respectively). There were no racial and ethnic differences in total health care expenditures among those with cognitive deficits without ADRD and those with ADRD. Across all three groups, however, Blacks, Asians, and Latinos consistently had lower out-of-pocket expenditures than whites (except for Asians with cognitive deficits without ADRD). Furthermore, service-specific health care expenditures varied by racial and ethnic groups.

CONCLUSIONS

Our study did not find significant racial and ethnic differences in total health care expenditures among Medicare beneficiaries with cognitive deficits and/or ADRD. However, we documented significant differences in out-of-pocket expenditures and service-specific expenditures. We speculated that the differences may be attributable to racial and ethnic differences in access to care and/or preferences based on family structure and cultural/economic factors. Particularly, heterogeneous patterns of service-specific expenditures by racial and ethnic groups underscore the importance of future research in identifying determinants leading to variations in service-specific expenditures among racial and ethnic groups.

Regional Hypoperfusion Predicts Decline in Everyday Functioning at Three-Year Follow-Up in Older Adults without Dementia

BACKGROUND

Increasing evidence indicates that cerebrovascular dysfunction may precede cognitive decline in aging and Alzheimer's disease (AD). Reduced cerebral blood flow (CBF) is associated with cognitive impairment in older adults. However, less is known regarding the association between CBF and functional decline, and whether CBF predicts functional decline beyond cerebrovascular and metabolic risk factors.

OBJECTIVE

To examine the association between regional CBF and functional decline in nondemented older adults.

METHOD

One hundred sixty-six (N = 166) participants without dementia from the Alzheimer's Disease Neuroimaging Initiative underwent neuropsychological testing and neuroimaging. Pulsed arterial spin labeling magnetic resonance imaging was acquired to quantify resting CBF. Everyday functioning was measured using the Functional Assessment Questionnaire at baseline and annual follow-up visit across three years.

RESULTS

Adjusting for age, education, sex, cognitive status, depression, white matter hyperintensity volume, cerebral metabolism, and reference (precentral) CBF, linear mixed effects models showed that lower resting CBF at baseline in the medial temporal, inferior temporal, and inferior parietal lobe was significantly associated with accelerated decline in everyday functioning. Results were similar after adjusting for conventional AD biomarkers, including cerebrospinal fluid (CSF) amyloid-β (Aβ) and hyperphosphorylated tau (p-tau) and apolipoprotein E (APOE) ɛ4 positivity. Individuals who later converted to dementia had lower resting CBF in the inferior temporal and parietal regions compared to those who did not.

CONCLUSION

Lower resting CBF in AD vulnerable regions including medial temporal, inferior temporal, and inferior parietal lobes predicted faster rates of decline in everyday functioning. CBF has utility as a biomarker in predicting functional declines in everyday life and conversion to dementia.

Medicare expenditures attributable to dementia

OBJECTIVE

To estimate dementia's incremental cost to the traditional Medicare program.

DATA SOURCES

Health and Retirement Study (HRS) survey-linked Medicare part A and B claims from 1991 to 2012.

STUDY DESIGN

We compared Medicare expenditures for 60 months following a claims-based dementia diagnosis to those for a randomly selected, matched comparison group.

DATA COLLECTION/EXTRACTION METHODS

We used a cost estimator that accounts for differential survival between individuals with and without dementia and decomposes incremental costs into survival and cost intensity components.

PRINCIPAL FINDINGS

Dementia's five-year incremental cost to the traditional Medicare program is approximately $15 700 per patient, nearly half of which is incurred in the first year after diagnosis. Shorter survival with dementia mitigates the incremental cost by about $2650. Increased costs for individuals with dementia were driven by more intensive use of Medicare part A covered services. The incremental cost of dementia was about $7850 higher for females than for males because of sex-specific differential mortality associated with dementia.

CONCLUSIONS

Dementia's cost to the traditional Medicare program is significant. Interventions that target early identification of dementia and preventable inpatient and post-acute care services could produce substantial savings.

Nursing Home Use Across The Spectrum of Cognitive Decline: Merging Mayo Clinic Study of Aging With CMS MDS Assessments

BACKGROUND/OBJECTIVES

Objective, complete estimates of nursing home (NH) use across the spectrum of cognitive decline are needed to help predict future care needs and inform economic models constructed to assess interventions to reduce care needs.

DESIGN

Retrospective longitudinal study.

SETTING

Olmsted County, MN.

PARTICIPANTS

Mayo Clinic Study of Aging participants assessed as cognitively normal (CN), mild cognitive impairment (MCI), previously unrecognized dementia, or prevalent dementia (age = 70-89 years; N = 3,545).

MEASUREMENTS

Participants were followed in Centers for Medicare and Medicaid Services (CMS) Minimum Data Set (MDS) NH records and in Rochester Epidemiology Project provider-linked medical records for 1-year after assessment of cognition for days of observation, NH use (yes/no), NH days, NH days/days of observation, and mortality.

RESULTS

In the year after cognition was assessed, for persons categorized as CN, MCI, previously unrecognized dementia, and prevalent dementia respectively, the percentages who died were 1.0%, 2.6%, 4.2%, 21%; the percentages with any NH use were 3.8%, 8.7%, 19%, 40%; for persons with any NH use, median NH days were 27, 38, 120, 305, and median percentages of NH days/days of observation were 7.8%, 12%, 33%, 100%. The year after assessment, among persons with prevalent dementia and any NH use, >50% were a NH resident all days of observation. Pairwise comparisons revealed that each increase in cognitive impairment category exhibited significantly higher proportions with any NH use. One-year mortality was especially high for persons with prevalent dementia and any NH use (30% vs 13% for those with no NH use); 58% of all deaths among persons with prevalent dementia occurred while a NH resident.

CONCLUSIONS

Findings suggest reductions in NH use could result from quality alternatives to NH admission, both among persons with MCI and persons with dementia, together with suitable options for end-of-life care among persons with prevalent dementia.

Early Cognitively Based Functional Limitations Predict Loss of Independence in Instrumental Activities of Daily Living in Older Adults

Older adults with early forms of neurodegenerative disease are at risk for functional disability, which is often defined by the loss of independence in instrumental activities of daily living (IADLs). The current study investigated the influence of mild changes in everyday functional abilities (referred to as functional limitations) on risk for development of incident functional disability. A total of 407 participants, who were considered cognitively normal or diagnosed with mild cognitive impairment (MCI) at baseline, were followed longitudinally over an average 4.1 years (range=0.8-9.2 years). Informant-based ratings from the Everyday Cognition (ECog; Farias et al., 2008) and the Instrumental Activities of Daily Living (Lawton & Brody, 1969) scales assessed the degree of functional limitations and incident IADL disability, respectively. Cox proportional hazards models revealed that more severe functional limitations (as measured by the Total ECog score) at baseline were associated with approximately a four-fold increased risk of developing IADL disability a few years later. Among the ECog domains, functional limitations in Everyday Planning, Everyday Memory, and Everyday Visuospatial domains were associated with the greatest risk of incident functional disability. These results remained robust even after controlling for participants' neuropsychological functioning on tests of executive functions and episodic memory. Current findings indicate that early functional limitations have prognostic value in identifying older adults at risk for developing functional disability. Findings highlight the importance of developing interventions to support everyday abilities related to memory, executive function, and visuospatial skills in an effort to delay loss of independence in IADLs.

Medicare Utilization and Expenditures Around Incident Dementia in a Multiethnic Cohort

BACKGROUND

Few studies have examined patterns of health care utilization and costs during the period around incident dementia.

METHODS

Participants were drawn from the Washington Heights-Inwood Columbia Aging Project, a multiethnic, population-based, prospective study of cognitive aging of Medicare beneficiaries in a geographically defined area of northern Manhattan. Medicare utilization and expenditure were examined in individuals with clinically diagnosed dementia from 2 years before until 2 years after the initial diagnosis. A sample of non-demented individuals who were matched on socio-demographic and clinical characteristics at study enrollment was used as controls. Multivariable regression analysis estimated effects on Medicare utilization and expenditures associated with incident dementia.

RESULTS

During the 2 years before incident dementia, rates of inpatient admissions and outpatient visits were similar between dementia patients and non-demented controls, but use of home health and skilled nursing care and durable medical equipment were already higher in dementia patients. Results showed a small but significant excess increase associated with incident dementia in inpatient admissions but not in other areas of care. In the 2 years before incident dementia, total Medicare expenditures were already higher in dementia patients than in non-demented controls. But we found no excess increases in Medicare expenditures associated with incident dementia.

CONCLUSIONS

Demand for medical care already is increasing and costs are higher at the time of incident dementia. There was a small but significant excess risk of inpatient admission associated with incident dementia.

The Moderating Effect of Personality Type on the Relationship between Leisure Activity and Executive Control in Older Adults

We examined the moderating effect of personality on the association between leisure activities and executive control in healthy community-dwelling older adults. We found two distinct personality typologies: individuals with a Resilient personality were characterized by emotional stability and self-confidence; whereas, those who resembled an Overcontrolled personality tended to be introverted, but also low on neuroticism. Resilient individuals were more likely than Overcontrolled individuals to demonstrate higher executive function and attention as a result of participation in mental activities. These results suggest that personality might be important to include in studies that test the efficacy of activity interventions for improving cognition.

Activities of daily living and quality of life across different stages of dementia: a UK study

OBJECTIVES

People with dementia (PwD) require an increasing degree of assistance with activities of daily living (ADLs), and dependency may negatively impact on their well-being. However, it remains unclear which activities are impaired at each stage of dementia and to what extent this is associated with variations in quality of life (QoL) across the different stages, which were the two objectives of this study.

METHODS

The sample comprised 122 PwD, and their carers, either living at home or recently admitted to long-term care. Measures of cognition and QoL were completed by the PwD and proxy measures of psychopathology, depression, ADLs and QoL were recorded. Using frequency, correlation and multiple regression analysis, data were analysed for the number of ADL impairments across mild, moderate and severe dementia and for the factors impacting on QoL.

RESULTS

ADL performance deteriorates differently for individual activities, with some ADLs showing impairment in mild dementia, including dressing, whereas others only deteriorate later on, including feeding. This decline may be seen in the degree to which carers perceive ADLs to explain the QoL of the PwD, with more ADLs associated with QoL in severe dementia. RESULTS of the regression analysis showed that total ADL performance however was only impacting on QoL in moderate dementia.

CONCLUSION

Knowledge about performance deterioration in different ADLs has implications for designing interventions to address specific activities at different stages of the disease. Furthermore, findings suggest that different factors are important to consider when trying to improve or maintain QoL at different stages.

Longitudinal trajectories of everyday function by diagnostic status

Generalized linear mixed models were used to examine longitudinal trajectories of everyday functional limitations by diagnostic stability/progression. Older adults (N = 384) were followed an average 3.6 years; participants were grouped by diagnosis at study baseline and last follow-up (normal cognition, Mild Cognitive Impairment, or dementia at each time point). At study baseline there were clear group differences; most notably among participants initially characterized as cognitively normal, those who developed Mild Cognitive Impairment or dementia over follow-up already demonstrated greater functional impairment compared with those who remained cognitively normal. Change in functional impairment progressed slowly in the early disease groups, but showed an accelerated worsening in those converting to dementia.

Age-related decline in divided-attention: from theoretical lab research to practical real-life situations

The purpose of this advanced review is to provide readers with an up-to-date synopsis of age-related changes in divided-attention abilities. An interdisciplinary approach is taken, supplying readers with evidence from very structured laboratory studies and findings from more ecological research studies that target real-life divided-attention situations (i.e., walking and talking). The review goes beyond the reported age-related declines in divided-attention abilities and offers the reader an overview of current cognitive (dual-task) training findings which suggest that these declines can be diminished with training. The contents of this review and the future directions proposed demonstrate that divided-attention research and its recent application to aging and mobility has become a major and fast growing scientific field of investigation. WIREs Cogn Sci 2013, 4:623-640. doi: 10.1002/wcs.1252 CONFLICT OF INTEREST: The authors have declared no conflicts of interest for this article. For further resources related to this article, please visit the WIREs website.