The Aging, Demographics, and Memory Study: Study Design and Methods

Impact of Care-Recipient Relationship Type on Quality of Life in Community-Dwelling Older Adults With Dementia Over Time

INTRODUCTION

Maintaining quality of life (QoL) has been identified as the primary goal of care services for person living with dementia (PLWD).

METHODS

A secondary analysis was conducted on five rounds of the National Health and Aging Trends Study (NHATS) over 4 years. A generalized estimating equation (GEE) was used to examine the prediction of relationship type on older adults' QoL through four domains: mental health, general health, functional limitations, and pain.

RESULTS

older adults cared for by an adult-child or multiple caregivers predicted increased risk for functional limitations after adjustment for their socio-demographic and dementia status (IRR = 1.53, CI [1.26, 1.86]; IRR = 1.36, CI [1.14, 1.61], respectively). The interaction between the relationship type and education was significant. Older adults with a high school education or below, who were cared for by an adult child, had a significantly higher risk of increasing functional limitations over 4 years compared to those cared for by a spouse/partner (contrast = .50, P = .01, 95% CI [.07, .93]; contrast=.52, P = .03, 95% CI [.03, 1.02]; respectively). Similarly, older adults with a high school education, who were cared for by multiple caregivers, also experienced a significantly higher risk of increasing functional limitations than those cared for by a spouse/partner (contrast = .44, P = .03, 95% CI [.02, .85]).

CONCLUSION

Our findings provide evidence of the significant contribution of relationship type on PLWD's QoL changes over time. They also help to prioritize resource allocation while addressing PLWD's demands by socio-demographics such as education level.

Keeping Us Young? Grandchild Caregiving and Older Adults' Cognitive Functioning

Objective

This study investigates longitudinal associations between providing care to grandchildren and cognitive functioning. It also examines heterogeneity in these relationships.

Background

Grandchild caregiving may support older adults' cognitive functioning by providing social engagement and emotional meaning. However, studies caution that time- intensive or custodial grandchild caregiving can take a toll on grandparents. The cognitive health implications of grandchild caregiving may thus depend on contexts including time spent providing care and living arrangements. They may also vary across sociodemographic groups and have greater effects on older adults who are more vulnerable to cognitive decline.

Method

Data came from the 1998-2016 waves of the Health and Retirement Study (HRS) and represented over 11,000 U.S. adults age 50+. Using linear growth curve and dynamic panel models, the analysis explored relationships between level of grandchild care and cognitive functioning over time and across sociodemographic, family, work and health characteristics.

Results

Those providing 100-199, 200-499 or 500+ hours of care to grandchildren had better cognitive functioning than non-caregivers regardless of whether they lived with grandchildren. Positive links between grandchild caregiving and cognition were stronger for lower income, non-working, and unpartnered adults and grew with age and functional limitations.

Conclusion

These findings suggest that providing care to minor grandchildren may help support cognitive functioning as adults age. They also support the hypothesis that more vulnerable or isolated groups of older adults may benefit the most from grandchild caregiving.

Long-term cognitive outcome after elective hip or knee total joint arthroplasty: A population-based observational study

BACKGROUND

One year after elective hip or knee total joint arthroplasty (TJA), >30% of older adults meet criteria for postoperative neurocognitive disorder. However, this is not contextualized with long-term cognitive outcomes in comparable surgical and nonsurgical controls. We analyzed population-based data to compare long-term cognitive outcomes in older adults after TJA, other surgeries, and with and without arthritis pain.

METHODS

This was a retrospective observational analysis of United States older adults in the Health and Retirement Study (HRS) who underwent elective TJA, or elective surgery without expected functional benefits (e.g., cholecystectomy; inguinal herniorrhaphy), between 1998 and 2018 at aged 65 or older. TJA recipients were also age- and sex-matched to nonsurgical controls who reported moderate-severe arthritic pain or denied pain, so that comparison groups included surgical and nonsurgical (pain-suffering and pain-free) controls. We modeled biennially-assessed memory performance, a measure of direct and proxy cognitive assessments, before and after surgery, normalized to the rate of memory decline ("cognitive aging") in controls to express effect size estimates as excess, or fewer, months of memory decline. We used linear mixed effects models adjusted for preoperative health and demographic factors, including frailty, flexibly capturing time before/after surgery (knots at -4, 0, 8 years; discontinuity at surgery).

RESULTS

There were 1947 TJA recipients (average age 74; 63% women; 1358 knee, 589 hip) and 1631 surgical controls (average age 76; 38% women). Memory decline 3 years after TJA was similar to surgical controls (5.2 [95% confidence interval, CI -1.2 to 11.5] months less memory decline in the TJA group, p = 0.11) and nonsurgical controls. At 5 years, TJA recipients experienced 5.0 [95% CI -0.9 to 10.9] months less memory decline than arthritic pain nonsurgical controls.

CONCLUSION

There is no systematic accelerated memory decline at 3 years after TJA compared with surgical or nonsurgical controls.

General cognitive ability in high school, attained education, occupational complexity, and dementia risk

INTRODUCTION

We address the extent to which adolescent cognition predicts dementia risk in later life, mediated by educational attainment and occupational complexity.

METHODS

Using data from Project Talent Aging Study (PTAS), we fitted two structural equation models to test whether adolescent cognition predicts cognitive impairment (CI) and Ascertain Dementia 8 (AD8) status simultaneously (NCognitive Assessment = 2477) and AD8 alone (NQuestionnaire = 6491) 60 years later, mediated by education and occupational complexity. Co-twin control analysis examined 82 discordant pairs for CI/AD8.

RESULTS

Education partially mediated the effect of adolescent cognition on CI in the cognitive assessment aample and AD8 in the questionnaire sample (Ps < 0.001). Within twin pairs, differences in adolescent cognition were small, but intrapair differences in education predicted CI status.

DISCUSSION

Adolescent cognition predicted dementia risk 60 years later, partially mediated through education. Educational attainment, but not occupational complexity, contributes to CI risk beyond its role as a mediator of adolescent cognition, further supported by the co-twin analyses.

HIGHLIGHTS

Project Talent Aging Study follows enrollees from high school for nearly 60 years. General cognitive ability in high school predicts later-life cognitive impairment. Low education is a risk partially due to its association with cognitive ability.

Analysis of agreement between measures of subjective cognitive impairment and probable dementia in the National Health and Aging Trends Study

BACKGROUND

Subjective cognitive impairment (SCI) measures in population-based surveys offer potential for dementia surveillance, yet their validation against established dementia measures is lacking.

METHODS

We assessed agreement between SCI and a validated probable dementia algorithm in a random one-third sample (n = 1936) of participants in the 2012 National Health and Aging Trends Study (NHATS).

RESULTS

SCI was more prevalent than probable dementia (12.2% vs 8.4%). Agreement between measures was 90.0% and of substantial strength. Misclassification rates were higher among older and less-educated subgroups due to higher prevalence of false-positive misclassification but did not vary by sex or race and ethnicity.

DISCUSSION

SCI sensitivity (63.4%) and specificity (92.5%) against dementia were comparable with similar metrics for the NHATS probable dementia measure against the "gold-standard" Aging, Demographics, and Memory Study-based dementia criteria, implying that population-based surveys may afford cost-effective opportunities for dementia surveillance to assess risk and inform policy.

HIGHLIGHTS

The prevalence of subjective cognitive impairment (SCI) is generally higher than that of a validated measure of probable dementia, particularly within the youngest age group, females, Whites, and persons with a college or higher degree. Percent agreement between SCI and a validated measure of probable dementia was 90.0% and of substantial strength (prevalence- and bias-adjusted kappa, 0.80). Agreement rates were higher in older and less-educated subgroups, driven by the higher prevalence of false-positive disagreement, but did not vary significantly by sex or race and ethnicity. SCI's overall sensitivity and specificity were 63.4% and 92.5%, respectively, against a validated measure of probable dementia, suggesting utility as a low-cost option for dementia surveillance. Heterogeneity in agreement quality across subpopulations warrants caution in its use for subgroup analyses.

Performance of probable dementia classification in a European multi-country survey

Feasibility constraints limit availability of validated cognitive assessments in observational studies. Algorithm-based identification of 'probable dementia' is thus needed, but no algorithm developed so far has been applied in the European context. The present study sought to explore the usefulness of the Langa-Weir (LW) algorithm to detect 'probable dementia' while accounting for country-level variation in prevalence and potential underreporting of dementia. Data from 56 622 respondents of the Survey of Health, Ageing and Retirement in Europe (SHARE, 2017) aged 60 years and older with non-missing data were analyzed. Performance of LW was compared to a logistic regression, random forest and XGBoost classifier. Population-level 'probable dementia' prevalence was compared to estimates based on data from the Organisation for Economic Co-operation and Development. As such, application of the prevalence-specific LW algorithm, based on recall and limitations in instrumental activities of daily living, reduced underreporting from 61.0 (95% CI, 53.3-68.7%) to 30.4% (95% CI, 19.3-41.4%), outperforming tested machine learning algorithms. Performance in other domains of health and cognitive function was similar for participants classified 'probable dementia' and those self-reporting physician-diagnosis of dementia. Dementia classification algorithms can be adapted to cross-national cohort surveys such as SHARE and help reduce underreporting of dementia with a minimal predictor set.

Prevalence of cognitive impairment in home health physical therapy

BACKGROUND

The prevalence of cognitive impairment in home health physical therapy (HHPT) is unknown. We sought to identify the prevalence of cognitive impairment, including cognitive impairment no dementia (CIND) and dementia, among older adults who used HHPT, and if cognitive impairment prevalence was higher among those with HHPT-relevant characteristics.

METHODS

For our cross-sectional analysis, we identified 963 fee-for-service Medicare beneficiaries with HHPT claims (>85 years old: 28.8%, women: 63.7%, non-Hispanic White: 82.1%) in the 2014 and 2016 waves of the Health and Retirement Study (HRS) and used a validated algorithm to categorize cognitive status as normal, CIND, or dementia. We estimated the population prevalence and calculated age, gender, race/ethnicity adjusted odds ratio (aOR) of CIND and dementia for characteristics relevant to HHPT service delivery including depression, walking difficulty, fall history, incontinence, moderate-vigorous physical activity (MVPA) ≤1x/week, and community-initiated HHPT using multinomial logistic regression.

RESULTS

The population prevalence of cognitive impairment was 46.4% (CIND: 27.3%, dementia: 19.1%). The prevalence of cognitive impairment was greater among those with depression (46.7% vs. 39.5%), difficulty walking across the room (58.9% vs. 41.8%), fall history (49.1% vs. 42.9%), MVPA ≤1x/week (50.0% vs. 38.0%), and community-initiated HHPT (55.2% vs. 40.2%). Compared to normal cognitive status, the odds of cognitive impairment were greater for those with MVPA≤1x/week (CIND: aOR = 1.57 [95% CI: 1.05-2.33], dementia: aOR = 2.55 [95% CI: 1.54-4.22]), depression (dementia: aOR = 1.99 [95% CI: 1.19-3.30]), difficulty walking across the room (dementia: aOR = 2.54 [95% CI: 1.40-4.60]), fall history (dementia: aOR = 1.85 [95% CI: 1.20-2.83]), and community-initiated HHPT (dementia: aOR = 1.72 (95% CI: 1.13-2.61]).

CONCLUSION

There is a high prevalence of CIND and dementia in HHPT, and no characteristics had a low prevalence of cognitive impairment. Physical therapists should be ready to identify cognitive impairment and adapt home health service delivery for this vulnerable population of older adults.

Factors associated with reduced sleep among spouses and caregivers of older adults with varying levels of cognitive decline

BACKGROUND

Caregivers of persons with cognitive decline (PWCD) are at increased risk of poor sleep quantity and quality. It is unclear whether this is due to factors in the caregiver versus in the PWCD.

METHODS

This secondary data analysis using Aging, Demographics, and Memory Study data from the Health Retirement Study examined factors contributing to reduced sleep/rest among spouses and caregivers of older adults with varying levels of cognitive decline (cognitively normal (CN), cognitive impairment but not dementia (CIND), or dementia).

RESULTS

In our preliminary analysis, among N = 218 spouses (not necessarily caregivers) (mean age (SD) = 73.77 (7.30); 70.64% female) of older adults with varying levels of cognitive decline, regression revealed that frequency of sleep complaints was lowest among spouses with CN partners, second highest with CIND partners, and highest with dementia-partners, X2  = 26.810, P = 0.002.

PRIMARY AIM

among n = 136 caregivers of PWCD (mean age (SD) = 59.27 (13.97); 74.26% female; 22.79% spouses), we analyzed whether caregiver reduced sleep/rest was predicted by PWCD factors (i.e., frequent nighttime waking, dementia severity) and/or caregiver factors (i.e., depression symptoms, caregiver role overload). Regression revealed that caregiver depression symptoms (d = 0.62) and role overload (d = 0.88), but not PWCD factors, were associated with reduced caregiver sleep/rest after adjusting for demographic factors, caregiving frequency, and shared-dwelling status (overall model: X2  = 31.876, P = 0.002). Exploratory analyses revealed that a caregiver was 7.901 times more likely (95% CI: 0.99-63.15) to endorse experiencing reduced sleep/rest if back-up care was not available (P = 0.023).

CONCLUSION

Findings highlight that the frequency of reported sleep problems among spouses increases in a stepwise fashion when partners have dementia versus CIND versus CN. The results also emphasise that caregiver mental health and burden are strongly associated with caregiver sleep disturbances and thus may be targets of intervention for caregiver sleep problems.

Longitudinal study of cognitive decline among women with and without urinary incontinence

BACKGROUND

Cross-sectional and short-term cohort studies have demonstrated an association between urinary incontinence and dementia, as well as lower performance on cognitive testing. The Health and Retirement Study, a longitudinal study of community-dwelling older adults, offers an opportunity to assess the temporal association between these conditions because it included an assessment of incontinence symptoms and biennial assessments of cognitive function.

OBJECTIVE

This study aimed to evaluate if urinary incontinence before the age of 70 years had an effect on changes in cognitive function among women participating in the Health and Retirement Study.

STUDY DESIGN

This secondary analysis included data from female respondents in the Health and Retirement Study aged 58 to 67 years with ≥2 cognitive assessments. Urinary incontinence was defined as any involuntary loss of any urine in the preceding 12 months. A control group without incontinence was reweighted for better comparability using coarsened exact matching for age and comorbidities. Validated methods, including neuropsychological test data, estimated a memory score and dementia probability for each participant biennially. Coprimary outcomes were the changes in memory score and dementia probability. Linear regression models were used to estimate the association of urinary incontinence with change in memory score and dementia probability, adjusting for baseline demographics and comorbidities. A subgroup analysis was performed to assess the effects of urinary incontinence frequency on these outcomes. The infrequent subgroup reported <15 days of leakage per month and the frequent subgroup reported ≥15 days of leakage per month.

RESULTS

Among eligible female respondents, 40.6% reported urinary incontinence between the ages of 58 and 69 years. Baseline memory scores and dementia probability were similar between those with urinary incontinence (n=1706) and controls (n=2507). Memory score declined significantly in both cohorts, indicating poorer memory over time (-0.222 among those with incontinence [95% confidence interval, -0.245 to -0.199] vs -0.207 in controls [95% confidence interval, -0.227 to -0.188]). The decline of memory score was not statistically significantly different between cases and controls (mean difference, -0.015; 95% confidence interval, -0.045 to 0.015). Dementia probability increased significantly in both groups, indicating a greater probability of developing dementia by 0.018 among those with incontinence (95% confidence interval, 0.015-0.020) and by 0.020 among controls (95% confidence interval, 0.017-0.022). The change in dementia probability was not significantly different between groups (mean difference, -0.002; 95% confidence interval, -0.006 to 0.002). Frequent urinary incontinence was reported in 105 of 1706 (6%) of those with urinary incontinence. Memory score declined and dementia probability increased with time (P<.001) in frequent and infrequent urinary incontinence subgroups. There was no dose-response relationship.

CONCLUSION

Measures of cognitive performance declined during approximately 10 years of observation. The changes in performance were not associated with the presence of urinary incontinence in the participants' younger years.

An outcome-wide analysis of the effects of diagnostic labeling of Alzheimer's disease and related dementias on social relationships

INTRODUCTION

This study examines how receiving a dementia diagnosis influences social relationships by race and ethnicity.

METHODS

Using data from the Health and Retirement Study (10 waves; 7,159 observations) of adults 70 years and older predicted to have dementia using Gianattasio-Power scores (91% accuracy), this study assessed changes in social support, engagement, and networks after a dementia diagnosis. We utilized quasi-experimental methods to estimate treatment effects and subgroup analyses by race/ethnicity.

RESULTS

A diagnostic label significantly increased the likelihood of gaining social support but reduced social engagement and one measure of social networks. With some exceptions, the results were similar by race and ethnicity.

DISCUSSION

Results suggest that among older adults with assumed dementia, being diagnosed by a doctor may influence social relationships in both support-seeking and socially withdrawn ways. This suggests that discussing services and supports at the time of diagnosis is important for healthcare professionals.

Cognitive impairment and partnership status in the United States, 1998-2016, by sex, race/ethnicity, and education

Cognitively impaired adults without a partner are highly disadvantaged, as partners constitute an important source of caregiving and emotional support. With the application of innovative multistate models to the Health and Retirement Study, this paper is the first to estimate joint expectancies of cognitive and partnership status at age 50 by sex, race/ethnicity, and education in the United States. We find that women live a decade longer unpartnered than men. Women are also disadvantaged as they experience three more years as both cognitively impaired and unpartnered than men. Black women live over twice as long as cognitively impaired and unpartnered compared with White women. Lower-educated men and women live around three and five years longer, respectively, as cognitively impaired and unpartnered than more highly educated men and women. This study addresses a novel facet of partnership and cognitive status dynamics and examines their variations by key socio-demographic factors.

Cost of care for Alzheimer's disease and related dementias in the United States: 2016 to 2060

Medical and long-term care for Alzheimer's disease and related dementias (ADRDs) can impose a large economic burden on individuals and societies. We estimated the per capita cost of ADRDs care in the in the United States in 2016 and projected future aggregate care costs during 2020-2060. Based on a previously published methodology, we used U.S. Health and Retirement Survey (2010-2016) longitudinal data to estimate formal and informal care costs. In 2016, the estimated per patient cost of formal care was $28,078 (95% confidence interval [CI]: $25,893-$30,433), and informal care cost valued in terms of replacement cost and forgone wages was $36,667 ($34,025-$39,473) and $15,792 ($12,980-$18,713), respectively. Aggregate formal care cost and formal plus informal care cost using replacement cost and forgone wage methods were $196 billion (95% uncertainty range [UR]: $179-$213 billion), $450 billion ($424-$478 billion), and $305 billion ($278-$333 billion), respectively, in 2020. These were projected to increase to $1.4 trillion ($837 billion-$2.2 trillion), $3.3 trillion ($1.9-$5.1 trillion), and $2.2 trillion ($1.3-$3.5 trillion), respectively, in 2060.

Geographic Relocation in Response to Parents' Health Shocks: Who Moves and How Close?

Objective

This article examines how parent-child geographic proximity changes around the onset of parental health shocks in the United States. Differences in the likelihood of moving closer across social groups are also investigated.

Background

Adult children often care for older parents with health problems, but this requires relatively close proximity. As families are becoming smaller and many adult children live away from their parents, it is unclear how responsive families will be to older adults' health problems.

Method

We estimate a series of fixed effects and event study models on data from the Health and Retirement Study (2004-2018) to assess changes in parent-child proximity after parents' first onset of cognitive impairment and functional limitations.

Results

We find robust evidence that parents and children tend to stay close or move closer to each other in response to parent's health declines. Moves occur immediately and in subsequent waves after the onset of health shocks. Reductions in parent-child distance are consistently larger among mother-daughter dyads, dyads without spouses or multiple children, and non-Hispanic white families.

Conclusion

The geographic availability of adult children to provide care is responsive to parents' needs. After the onset of a serious health condition, most older adults have a spouse or child living close enough to provide care. Parents' and children's lives are dynamically linked, and either or both may relocate to facilitate care.

Investigating the prevalence of cognitive impairment and dementia in the Northern Ireland Cohort for the Longitudinal Study of Ageing (NICOLA): the Harmonised Cognitive Assessment Protocol (HCAP) cross-sectional substudy

INTRODUCTION

The Northern Ireland Cohort for the Longitudinal Study of Ageing (NICOLA) study is the largest study of ageing in Northern Ireland (NI). The Harmonised Cognitive Assessment Protocol (HCAP) is a substudy of NICOLA designed to assess cognitive impairment and dementia in individuals aged 65 and over. The NICOLA-HCAP substudy is funded by the National Institute on Aging as part of a network for enhancing cross-national research within a worldwide group of population-based, longitudinal studies of ageing, all of which are centred around the US-based Health and Retirement Study.

METHODS AND ANALYSIS

The NICOLA-HCAP study will draw on the main NICOLA cohort (of 8283 participants) and randomly sample 1000 participants aged 65 and over to take part in the substudy. Participants will complete a series of cognitive tests (n=19) via a computer-assisted personal interview administered in their home (or alternatively within the research centre) and will be asked to nominate a family member or friend to complete an additional interview of validated instruments to provide information on respondent's prior and current cognitive and physical functioning and whether the individual requires help with daily activities. The objectives of the study are: to investigate the prevalence of dementia and cognitive impairment in NICOLA; harmonise scoring of the NICOLA-HCAP data to the HCAP studies conducted in Ireland, the USA and England; to explore the validity of dementia estimates; and investigate the risk factors for dementia and cognitive impairment.

ETHICS AND DISSEMINATION

The study received ethical approval from the Faculty of Medicine, Health and Life Sciences Research Ethics Committee, Queen's University Belfast. We will provide data from the Northern Irish HCAP to the research community via data repositories such as the Dementias Platform UK and Gateway to Global Aging to complement existing public data resources and support epidemiological research by others. Findings will also be disseminated through peer-reviewed publications and at international conferences.

Modeling Risk Factors for Intraindividual Variability: A Mixed-Effects Beta-Binomial Model Applied to Cognitive Function in Older People in the English Longitudinal Study of Ageing

Cognitive functioning in older age profoundly impacts quality of life and health. While most research on cognition in older age has focused on mean levels, intraindividual variability (IIV) around this may have risk factors and outcomes independent of the mean value. Investigating risk factors associated with IIV has typically involved deriving a summary statistic for each person from residual error around a fitted mean. However, this ignores uncertainty in the estimates, prohibits exploring associations with time-varying factors, and is biased by floor/ceiling effects. To address this, we propose a mixed-effects location scale beta-binomial model for estimating average probability and IIV in a word recall test in the English Longitudinal Study of Ageing. After adjusting for mean performance, an analysis of 9,873 individuals across 7 (mean = 3.4) waves (2002-2015) found IIV to be greater at older ages, with lower education, in females, with more difficulties in activities of daily living, in later birth cohorts, and when interviewers recorded issues potentially affecting test performance. Our study introduces a novel method for identifying groups with greater IIV in bounded discrete outcomes. Our findings have implications for daily functioning and care, and further work is needed to identify the impact for future health outcomes.

Cognitive decline among older adults with depressive symptoms before and during the COVID-19 pandemic

BACKGROUND

Whether the COVID-19 pandemic would induce accelerated cognitive decline in individuals with depressive symptoms is undetermined.

OBJECTIVE

To investigate the impact of the COVID-19 pandemic on cognitive function among older adults with depressive symptoms.

METHODS

Data were from the Health and Retirement Study. The interval between wave 13 and wave 14 was defined as the prepandemic period, and the interval between wave 14 and wave 15 was defined as the pandemic period. Linear mixed models and modified Poisson regression models were employed to compare the differences in cognitive decline and incident dementia between participants with and without depressive symptoms before and during the pandemic.

RESULTS

A total of 9304 participants were included. During the prepandemic period, no significant difference was observed in changes in cognitive scores between participants with and without depressive symptoms. During the pandemic period, an accelerated decline in cognitive scores was found between the two groups (global cognition: -0.25, 95 % CI: -0.41 to -0.08, P = 0.004; memory: -0.16, 95 % CI: -0.31 to -0.02, P = 0.030; executive function: -0.08, 95 % CI: -0.15 to -0.02, P = 0.014). Participants with depressive symptoms had a higher risk of developing dementia during the pandemic (RR: 1.48, 95 % CI: 1.17 to 1.88, P < 0.001).

LIMITATIONS

Causal relationship cannot be concluded due to the observational study design.

CONCLUSIONS

Older adults with depressive symptoms suffered more severe cognitive deterioration and had a higher risk of incident dementia during the pandemic, underscoring the need to provide cognitive monitoring and interventions for those with depressive symptoms during the COVID-19 pandemic.

Factor structure of the Harmonized Cognitive Assessment Protocol neuropsychological battery in the Health and Retirement Study

OBJECTIVE

The Harmonized Cognitive Assessment Protocol (HCAP) describes an assessment battery and a family of population-representative studies measuring neuropsychological performance. We describe the factorial structure of the HCAP battery in the US Health and Retirement Study (HRS).

METHOD

The HCAP battery was compiled from existing measures by a cross-disciplinary and international panel of researchers. The HCAP battery was used in the 2016 wave of the HRS. We used factor analysis methods to assess and refine a theoretically driven single and multiple domain factor structure for tests included in the HCAP battery among 3,347 participants with evaluable performance data.

RESULTS

For the eight domains of cognitive functioning identified (orientation, memory [immediate, delayed, and recognition], set shifting, attention/speed, language/fluency, and visuospatial), all single factor models fit reasonably well, although four of these domains had either 2 or 3 indicators where fit must be perfect and is not informative. Multidimensional models suggested the eight-domain model was overly complex. A five-domain model (orientation, memory delayed and recognition, executive functioning, language/fluency, visuospatial) was identified as a reasonable model for summarizing performance in this sample (standardized root mean square residual = 0.05, root mean square error of approximation = 0.05, confirmatory fit index = 0.94).

CONCLUSIONS

The HCAP battery conforms adequately to a multidimensional structure of neuropsychological performance. The derived measurement models can be used to operationalize notions of neurocognitive impairment, and as a starting point for prioritizing pre-statistical harmonization and evaluating configural invariance in cross-national research.

The Prevalence of Cognitive Impairment Among Medicare Beneficiaries Who Use Outpatient Physical Therapy

OBJECTIVE

The objective of this study was to estimate the prevalence of cognitive impairment (including cognitive impairment no dementia [CIND] and dementia) among Medicare fee-for-service beneficiaries who used outpatient physical therapy and to estimate the prevalence of cognitive impairment by measures that are relevant to rehabilitation practice.

METHODS

This cross-sectional analysis included 730 Medicare fee-for-service beneficiaries in the 2016 wave of the Health and Retirement Study with claims for outpatient physical therapy. Cognitive status, our primary variable of interest, was categorized as normal, CIND, or dementia using a validated approach, and population prevalence of cognitive impairment (CIND and dementia) was estimated by sociodemographic variables and Charlson comorbidity index score. Age-, gender- (man/woman), race-/ethnicity-adjusted population prevalence of CIND and dementia were also calculated for walking difficulty severity, presence of significant pain, self-reported fall history, moderate-vigorous physical activity (MVPA) ≤1×/week, and sleep disturbance frequency using multinomial logistic regression.

RESULTS

Among Medicare beneficiaries with outpatient physical therapist claims, the prevalence of any cognitive impairment was 20.3% (CIND:15.2%, dementia:5.1%). Cognitive impairment was more prevalent among those who were older, Black, had lower education attainment, or higher Charlson comorbidity index scores. The adjusted population prevalence of cognitive impairment among those who reported difficulty walking across the room was 29.8%, difficulty walking 1 block was 25.9%, difficulty walking several blocks was 20.8%, and no difficulty walking was 16.3%. Additionally, prevalence of cognitive impairment among those with MVPA ≤1×/week was 27.1% and MVPA >1×/week was 14.1%. Cognitive impairment prevalence did not vary by significant pain, self-reported fall history, or sleep disturbance.

CONCLUSION

One in 5 older adults who use outpatient physical therapist services have cognitive impairment. Furthermore, cognitive impairment is more common in older physical therapist patients who report worse physical function and less physical activity.

IMPACT

Physical therapists should consider cognitive screening for vulnerable older adults to inform tailoring of clinical practice toward a patient's ability to remember and process rehabilitation recommendations.

Perceived discrimination and nativity status: risk of cognitive impairment among Latin American older adults

OBJECTIVES

We examined the association between perceived discrimination and the risk of cognitive impairment with no dementia (CIND) and Alzheimer's disease and related dementias (ADRD) while considering the potential effects of nativity status.

DESIGN

A prospective analysis of discrimination and nativity status with dementia and cognitive impairment was conducted among Latinx adults aged 51 years and older who participated in the Health and Retirement Study.

SETTING

A national representative sample.

PARTICIPANTS

A sample of 1,175 Latinx adults aged 51 years and older.

MEASUREMENTS

Demographics, cognitive functioning, perceived discrimination, and nativity status (US-born vs. non-US born) were assessed. Traditional survival analysis methods (Fine and gray models) were used to account for the semi-competing risk of death with up to 10 years of follow-up.

RESULTS

According to our results, neither everyday discrimination nor nativity status on their own had a statistically significant association with CIND/ADRD; however, non-US-born Latinx adults who reported no discrimination had a 42% lower risk of CIND/ADRD (SHR = 0.58 [0.41, 0.83], p = .003) than US-born adults.

CONCLUSIONS

These results highlight the need for healthcare providers to assess for discrimination and provide support and resources for those experiencing discrimination. It also highlights the need for better policies that address discrimination and reduce health disparities.

Health care utilization and costs in the years preceding dementia identification

INTRODUCTION

There is evidence that health care utilization increases after incident dementia, particularly after dementia diagnosis and toward the end of life; however, less is known about utilization in the years before dementia identification.

METHODS

In this retrospective cohort study we obtained data on n = 5547 beneficiaries from the Health and Retirement Study (HRS)-Medicare linked sample (n = 1241 with and n = 4306 without dementia) to compare longitudinal trends in health care costs and utilization in the 6 years preceding dementia identification relative to a confounder-balanced reference group without dementia.

RESULTS

We found that persons with dementia had a greater prevalence of outpatient emergency department (ED), inpatient hospital, skilled nursing, and home health use, and total health care costs in the years preceding dementia identification compared to their similar counterparts without dementia across a comparable timespan in later life.

CONCLUSIONS

This study provides evidence to suggest greater healthcare burden may exist well before clinical manifestation and identification of dementia.

HIGHLIGHTS

Several studies have documented the tremendous healthcare-related costs of living with dementia, particularly toward the end of life. Dementia is a progressive neurodegenerative disease, which, for some, includes a prolonged pre-clinical phase. However, health services research to date has seldom considered the time before incident dementia. This study documents that health care utilization and costs are significantly elevated in the years before incident dementia relative to a demographically-similar comparison group without dementia.

Mechanisms of Change in Cognitive Function Domains Among Older Adults in Cognitive Deterioration and Improvement Groups: Evidence From Phenotypic Network Structure

OBJECTIVE

To investigate how cognitive function domains change in phenotypic networks in cognitive deterioration and improvement groups.

DESIGN

Secondary data analysis.

SETTING AND PARTICIPANTS

Respondents in the Aging, Demographics, and Memory Study (ADAMS) who were 70 years or older at the time of the data collection in 2000 or 2002.

METHODS

This study used data from the ADAMS in Wave A and Wave B. We assessed 12 cognitive function domains. Latent profile transition analysis (LPTA) and the cross-lagged panel network model were used to the dynamic interactions of the 12 cognitive function domains over time in both the deterioration and improvement groups.

RESULTS

A total of 252 participants were included in the final analysis. LPTA identified 5 subgroups and categorized all samples into 3 main categories: improvement group (n = 61), deterioration group (n = 54), and no change group (n = 137). "D9: psychomotor processing" showed the largest value of out-strength in the deterioration group (r = 0.941) and improvement group (r = 0.969). The strongest direct positive effect in the deterioration group was "C9: psychomotor processing" -> "C8: attention" [β = 0.39 (0.00, 1.13)]. In the improvement group, the strongest direct positive effect was "C9 = psychomotor processing" -> "C7 = visual memory" [β = 0.69 (0.07, 1.30)].

CONCLUSION AND IMPLICATIONS

Psychomotor processing affected other cognitive domains, and it played a crucial role in changes of cognitive function. The paths of psychomotor processing to attention and visual memory were found to be major factors in cognitive deterioration and improvement. Targeting psychomotor processing may lead to the development of more effective and precise interventions.

Association between BMI trajectories in late-middle age and subsequent dementia risk in older age: a 26-year population-based cohort study

BACKGROUND

The association between body mass index (BMI) and dementia risk differs depending on follow-up time and age at BMI measurement. The relationship between BMI trajectories in late-middle age (50-65 years old) and the risk of dementia in older age (> 65 years old) has not been revealed.

METHODS

In the present study, participants from the Health and Retirement Study were included. BMI trajectories were constructed by combining BMI trend and variation information. The association between BMI trajectories at the age of 50-65 years and dementia risk after the age of 65 years was investigated. Participants with European ancestry and information on polygenic scores for cognitive performance were pooled to examine whether genetic predisposition could modify the association.

RESULTS

A total of 10,847 participants were included in the main analyses. A declining BMI trend and high variation in late-middle age were associated with the highest subsequent dementia risk in older age compared with an ascending BMI trend and low variation (RR = 1.76, 95% CI = 1.45-2.13). Specifically, in stratified analyses on BMI trajectories and dementia risk based on each individual's mean BMI, the strongest association between a declining BMI trend with high variation and elevated dementia risk was observed in normal BMI group (RR = 2.66, 95% CI = 1.72-4.1). Similar associations were found when participants were stratified by their genetic performance for cognition function without interaction.

CONCLUSIONS

A declining BMI trend and high variation in late-middle age were associated with a higher risk of dementia. Early monitoring of these individuals is needed to prevent dementia in older individuals.

Assessing cognitive function in longitudinal studies of ageing worldwide: some practical considerations

Over 55 million people live with dementia worldwide. With 40% of modifiable risk factors estimated to contribute to dementia, the potential for prevention is high, and preventive measures, at an early stage of cognitive decline, are likely to positively influence future dementia trends. Countries need reliable health data and adequate measurement tools to quantify, monitor and track early changes in cognitive capacity in the general population. Many cognitive tests exist; however, there is no consensus to date about which instruments should be employed, and important variations in measurement have been observed. In this narrative review, we present a number of cognitive tests that have been used in nationally representative population-based longitudinal studies of ageing. Longitudinal panel studies of ageing represent critical platforms towards capturing the process of cognitive ageing and understanding associated risk and protective factors. We highlight optimal measures for use at a population level and for cross-country comparisons, taking into consideration instrument reliability, validity, duration, ease of administration, costs, literacy and numeracy requirements, adaptability to sensory and fine motor impairments and portability to different cultural and linguistic milieux. Drawing upon the strengths and limitations of each of these tests, and the experience gained and lessons learnt from conducting a nationally representative study of ageing, we indicate a comprehensive battery of tests for the assessment of cognitive capacity, designed to facilitate its standardised operationalisation worldwide.

Telehealth Use Among Older Adults With Sensory, Cognitive, and Physical Impairments: A Substitute or Supplement to Traditional Care?

OBJECTIVES

Telehealth use flourished during the COVID-19 pandemic, as older patients faced obstacles to seeking in-person care. Heavy reliance on telehealth may continue postpandemic, due to increased Medicare investments in its use. However, it is unclear if older adults with disabilities face obstacles to effective telehealth use. We evaluate (a) how sensory, physical, and cognitive impairments affect older adults' use of telehealth only, traditional in-person care only, neither, or both (i.e., combined care); and (b) whether these patterns differ on the basis of socioeconomic and social resources that may facilitate telehealth use.

METHOD

Data are from the Self-Administered Questionnaire in the 2020 wave of the Health and Retirement Study (n = 4,453). We estimated multinomial logistic regression models to evaluate associations between impairments and health care service use and tested 2-way interaction terms to evaluate moderation effects.

RESULTS

Persons without impairments were most likely to use combined care, considered the optimal form of care. Persons with vision or cognitive impairment were more likely to use telehealth or traditional care only, whereas persons with 3 or more physical limitations were least likely to use telehealth alone, relative to combined care. Patterns did not differ significantly on the basis of any of the potential moderators.

DISCUSSION

We discuss implications for health care policy and practice, in light of reimbursement changes proposed by the Centers for Medicare and Medicaid Services for telehealth services. These proposals include the elimination of voice-only services which may be particularly beneficial to vision-impaired older adults.

Cognitive impairment indicator for the neuropsychological test batteries in the Canadian Longitudinal Study on Aging: definition and evidence for validity

BACKGROUND

Prevalence of overall cognitive impairment based on each participant's performance across a neuropsychological battery is challenging; consequently, we define and validate a dichotomous cognitive impairment/no cognitive indicator (CII) using a neuropsychological battery administered in a population-based study. This CII approximates the clinical practice of interpretation across a neuropsychological battery and can be applied to any neuropsychological dataset.

METHODS

Using data from participants aged 45-85 in the Canadian Longitudinal Study on Aging receiving a telephone-administered neuropsychological battery (Tracking, N = 21,241) or a longer in-person battery (Comprehensive, N = 30,097), impairment was determined for each neuropsychological test based on comparison with normative data. We adjusted for the joint probability of abnormally low scores on multiple neuropsychological tests using baserates of low scores demonstrated in the normative samples and created a dichotomous CII (i.e., cognitive impairment vs no cognitive impairment). Convergent and discriminant validity of the CII were assessed with logistic regression analyses.

RESULTS

Using the CII, the prevalence of cognitive impairment was 4.3% in the Tracking and 5.0% in the Comprehensive cohorts. The CII demonstrated strong convergent and discriminant validity.

CONCLUSIONS

The approach for the CII is a feasible method to identify participants who demonstrate cognitive impairment on a battery of tests. These methods can be applied in other epidemiological studies that use neuropsychological batteries.

Racial, Ethnic, Nativity, and Educational Disparities in Cognitive Impairment and Activity Limitations in the United States, 1998-2016

Despite extensive research on cognitive impairment and limitations in basic activities of daily living, no study has investigated the burden of their co-occurrence (co-impairment). Using the Health and Retirement Study data and incidence-based multistate models, we study the population burden of co-impairment using three key indicators: mean age at onset, lifetime risk, and health expectancy. We examine patterns by gender, race, ethnicity, nativity, education, and their interactions for U.S. residents aged 50-100. Furthermore, we analyze what fractions of racial, ethnic, and nativity disparities in co-impairment are attributable to inequalities in educational attainment. Results reveal that an estimated 56% of women and 41% of men aged 50 will experience co-impairment in their remaining life expectancy. Men experience an earlier onset of co-impairment than women (74 vs. 77 years), and women live longer in co-impairment than men (3.4 vs. 1.9 years). Individuals who are Black, Latinx, and lower educated, especially those experiencing intersecting disadvantages, have substantially higher lifetime risk of co-impairment, earlier co-impairment onset, and longer life in co-impairment than their counterparts. Up to 75% of racial, ethnic, and nativity disparity is attributable to inequality in educational attainment. This study provides novel insights into the burden of co-impairment and offers evidence of dramatic disparities in the older U.S. population.

The Association of Cognitive Status and Post-Operative Opioid Prescribing in Older Adults

Objective

To examine the differences in opioid prescribing by cognitive status following common elective surgical procedures among Medicare beneficiaries.

Background

Older individuals commonly experience changes in cognition with age. Although opioid prescribing is common after surgery, differences in opioid prescribing after surgery by cognitive status are poorly understood.

Methods

We conducted a retrospective analysis of patients ≥65 years participating in the Health and Retirement Study (HRS) linked with Medicare claims data who underwent surgeries between January 2007 and November 2016 and had cognitive assessments before the index operation. Cognitive status was defined as normal cognition, mild cognitive impairment (MCI), or dementia. Outcomes assessed were initial perioperative opioid fill rates, refill rates, and high-risk prescriptions fill rates. The total amount of opioids filled during the 30-day postdischarge period was also assessed. Adjusted rates were estimated for patient factors using the Cochran-Armitage test for trend.

Results

Among the 1874 patients included in the analysis, 68% had normal cognition, 21.3% had MCI, and 10.7% had dementia. Patients with normal cognition (58.1%) and MCI (54.5%) had higher initial preoperative fill rates than patients with dementia (33.5%) (P < 0.001). Overall, patients with dementia had similar opioid refill rates (21%) to patients with normal cognition (24.1%) and MCI (26.5%) (P = 0.322). Although prior opioid exposure did not differ by cognitive status (P = 0.171), among patients with high chronic preoperative use, those with dementia had lower adjusted prescription sizes filled within 30 days following discharge (281 OME) than patients with normal cognition (2147 OME) and MCI (774 OME) (P < 0.001; P = 0.009 respectively). Among opioid-naive patients, patients with dementia also filled smaller prescription sizes (97 OME) compared to patients with normal cognition (205 OME) and patients with MCI (173 OME) (P < 0.001 and P = 0.019, respectively).

Conclusions

Patients with dementia are less likely to receive postoperative prescriptions, less likely to refill prescriptions, and receive prescriptions of smaller sizes compared to patients with normal cognition or MCI. A cognitive assessment is an additional tool surgeons can use to determine a patient's individualized postoperative pain control plan.

Gender of Study Partners and Research Participants Associated With Differences in Study Partner Ratings of Cognition and Activity Level

OBJECTIVES

Studies of Alzheimer's disease typically include "study partners" (SPs) who report on participants' cognition and function. Prior studies show SP reports differ depending on the relationship between the SP and participant, that is, spouse or adult child. Adult children SPs are typically female. Could differing reports be due to gender? Knowing this may help explain variability in measurement.

METHODS

The Aging, Demographics, and Memory Study enrolled a subset of participants from the Health and Retirement Study. Each participant had an SP. Bivariate and multivariable regression models compared 718 SP-participant dyads.

RESULTS

In analyses of 4 groups defined by SP and participant gender, dyads composed of 2 women were less likely to identify as White (75.8%, 95% confidence interval [CI], 70.4-80.5) than dyads composed of 2 men (93.3%, 95% CI, 81.2-97.8). In analyses adjusted for the severity of cognitive and functional impairment, women SPs rated women participants as more active than they rated men, mean 2.15 (95% CI, 2.07-2.22) versus mean 2.30 (95% CI, 2.24-2.37), respectively, on a 4-point scale. Similarly, men SPs rated women participants as more active than they rated men, mean 2.1 (95% CI, 2.0-2.2) and mean 2.4 (95% CI, 2.3-2.5), respectively. In an analysis of cognitively unimpaired participants, women SPs rated participants' memory worse than men SPs did (p < .05).

DISCUSSION

SP and participant gender influence SPs' reports of another person's cognition and activity level. Our findings expand what is understood about how nondisease factors influence measures of disease severity.

CogDrisk, ANU-ADRI, CAIDE, and LIBRA Risk Scores for Estimating Dementia Risk

Importance

While the Australian National University-Alzheimer Disease Risk Index (ANU-ADRI), Cardiovascular Risk Factors, Aging, and Dementia (CAIDE), and Lifestyle for Brain Health (LIBRA) dementia risk tools have been widely used, a large body of new evidence has emerged since their publication. Recently, Cognitive Health and Dementia Risk Index (CogDrisk) and CogDrisk for Alzheimer disease (CogDrisk-AD) risk tools have been developed for the assessment of dementia and AD risk, respectively, using contemporary evidence; comparison of the relative performance of these risk tools is limited.

Objective

To evaluate the performance of CogDrisk, ANU-ADRI, CAIDE, LIBRA, and modified LIBRA (LIBRA with age and sex estimates from ANU-ADRI) in estimating dementia and AD risks (with CogDrisk-AD and ANU-ADRI).

Design, Setting, and Participants

This population-based cohort study obtained data from the Rush Memory and Aging Project (MAP), the Cardiovascular Health Study Cognition Study (CHS-CS), and the Health and Retirement Study-Aging, Demographics and Memory Study (HRS-ADAMS). Participants who were free of dementia at baseline were included. The factors were component variables in the risk tools that included self-reported baseline demographics, medical risk factors, and lifestyle habits. The study was conducted between November 2021 and March 2023, and statistical analysis was performed from January to June 2023.

Main outcomes and measures

Risk scores were calculated based on available factors in each of these cohorts. Area under the receiver operating characteristic curve (AUC) was calculated to measure the performance of each risk score. Multiple imputation was used to assess whether missing data may have affected estimates for dementia risk.

Results

Among the 6107 participants in 3 validation cohorts included for this study, 2184 participants without dementia at baseline were available from MAP (mean [SD] age, 80.0 [7.6] years; 1606 [73.5%] female), 548 participants without dementia at baseline were available from HRS-ADAMS (mean [SD] age, 79.5 [6.3] years; 288 [52.5%] female), and 3375 participants without dementia at baseline were available from CHS-CS (mean [SD] age, 74.8 [4.9] years; 1994 [59.1%] female). In all 3 cohorts, a similar AUC for dementia was obtained using CogDrisk, ANU-ADRI, and modified LIBRA (MAP cohort: CogDrisk AUC, 0.65 [95% CI, 0.61-0.69]; ANU-ADRI AUC, 0.65 [95% CI, 0.61-0.69]; modified LIBRA AUC, 0.65 [95% CI, 0.61-0.69]; HRS-ADAMS cohort: CogDrisk AUC, 0.75 [95% CI, 0.71-0.79]; ANU-ADRI AUC, 0.74 [95% CI, 0.70-0.78]; modified LIBRA AUC, 0.75 [95% CI, 0.71-0.79]; CHS-CS cohort: CogDrisk AUC, 0.70 [95% CI, 0.67-0.72]; ANU-ADRI AUC, 0.69 [95% CI, 0.66-0.72]; modified LIBRA AUC, 0.70 [95% CI, 0.68-0.73]). The CAIDE and LIBRA also provided similar but lower AUCs than the 3 aforementioned tools (eg, MAP cohort: CAIDE AUC, 0.50 [95% CI, 0.46-0.54]; LIBRA AUC, 0.53 [95% CI, 0.48-0.57]). The performance of CogDrisk-AD and ANU-ADRI in estimating AD risks was also similar.

Conclusions and relevance

CogDrisk and CogDrisk-AD performed similarly to ANU-ADRI in estimating dementia and AD risks. These results suggest that CogDrisk and CogDrisk-AD, with a greater range of modifiable risk factors compared with other risk tools in this study, may be more informative for risk reduction.

Estimating Transition Probabilities Across the Alzheimer's Disease Continuum Using a Nationally Representative Real-World Database in the United States

INTRODUCTION

Clinical Alzheimer's disease (AD) begins with mild cognitive impairment (MCI) and progresses to mild, moderate, or severe dementia, constituting a disease continuum that eventually leads to death. This study aimed to estimate the probabilities of transitions across those disease states.

METHODS

We developed a mixed-effects multi-state Markov model to estimate the transition probabilities, adjusted for 5 baseline covariates, using the Health and Retirement Study (HRS) database. HRS surveys older adults in the United States bi-annually. Alzheimer states were defined using the modified Telephone Interview of Cognitive Status (TICS-m).

RESULTS

A total of 11,292 AD patients were analyzed. Patients were 70.8 ± 9.0 years old, 54.9% female, and with 12.0 ± 3.3 years of education. Within 1 year from the initial state, the model estimated a higher probability of transition to the next AD state in earlier disease: 12.8% from MCI to mild AD and 5.0% from mild to moderate AD, but < 1% from moderate to severe AD. After 10 years, the probability of transition to the next state was markedly higher for all states, but still higher in earlier disease: 29.8% from MCI to mild AD, 23.5% from mild to moderate AD, and 5.7% from moderate to severe AD. Across all AD states, the probability of transition to death was < 5% after 1 year and > 15% after 10 years. Older age, fewer years of education, unemployment, and nursing home stay were associated with a higher risk of disease progression (p < 0.01).

CONCLUSIONS

This analysis shows that the risk of progression is greater in earlier AD states, increases over time, and is higher in patients who are older, with fewer years of education, unemployed, or in a nursing home at baseline. The estimated transition probabilities can provide guidance for future disease management and clinical trial design optimization, and can be used to refine existing cost-effectiveness frameworks.

Decision Making for Patients With Severe Dementia Versus Normal Cognition Near the End of Life

Background and Objectives

The clinical progression of severe dementia frequently leads to situations where surrogate decision makers must quickly make choices about potentially burdensome treatments that offer limited clinical benefit. We examined whether the number of decision makers and their access to advance directives were related to treatment choice for patients with severe dementia in comparison to those with normal cognition.

Research Design and Methods

We retrospectively linked survey responses about end-of-life treatment decisions to Medicare claims for Health and Retirement Study respondents dying between 2002 and 2015 whose next-of-kin reported a need for surrogate decision making. We estimated multivariable logistic regression models to study measures of aggressive care in the last 6 months of life; in-hospital death, burdensome transfers, and burdensome treatments.

Results

Compared to patients who were cognitively normal near the end of life (n = 1 198), patients with severe dementia (n = 722) were less likely to experience burdensome treatments (18% [95% confidence interval {CI} 14-21] vs 32% [95% CI 29-35]), burdensome transfers (20% [95% CI 17-24] vs 30% [95% CI 27-33]), and in-hospital death (24% [95% CI 20-28] vs 30% [95% CI 26-33]) when surrogates were involved. Rates of burdensome treatments, transfers, or in-hospital death for decedents with severe dementia did not vary with single versus multiple decision makers or when decision makers were informed by advance directives. However, among decedents with normal cognition, a single decision maker informed by an advance directive was associated with the lowest rates of burdensome treatments and in-hospital death.

Discussion and Implications

Surrogate decision makers made similar choices around end-of-life care for patients with severe dementia regardless of the number of decision makers and availability of advance directives. However, both advance directives and single decision makers were associated with less aggressive care for cognitively normal decedents.

Six-Year Cognitive Trajectory in Older Adults Following Major Surgery and Delirium

Importance

The study results suggest that delirium is the most common postoperative complication in older adults and is associated with poor outcomes, including long-term cognitive decline and incident dementia.

Objective

To examine the patterns and pace of cognitive decline up to 72 months (6 years) in a cohort of older adults following delirium.

Design, Setting, and Participants

This was a prospective, observational cohort study with long-term follow-up including 560 community-dwelling older adults (older than 70 years) in the ongoing Successful Aging after Elective Surgery study that began in 2010. The data were analyzed from 2021 to 2022.

Exposure

Development of incident delirium following major elective surgery.

Main Outcomes and Measures

Delirium was assessed daily during hospitalization using the Confusion Assessment Method, which was supplemented with medical record review. Cognitive performance using a comprehensive battery of neuropsychological tests was assessed preoperatively and across multiple points postoperatively to 72 months of follow-up. We evaluated longitudinal cognitive change using a composite measure of neuropsychological performance called the general cognitive performance (GCP), which is scaled so that 10 points on the GCP is equivalent to 1 population SD. Retest effects were adjusted using cognitive test results in a nonsurgical comparison group.

Results

The 560 participants (326 women [58%]; mean [SD] age, 76.7 [5.2] years) provided a total of 2637 person-years of follow-up. One hundred thirty-four participants (24%) developed postoperative delirium. Cognitive change following surgery was complex: we found evidence for differences in acute, post-short-term, intermediate, and longer-term change from the time of surgery that were associated with the development of postoperative delirium. Long-term cognitive change, which was adjusted for practice and recovery effects, occurred at a pace of about -1.0 GCP units (95% CI, -1.1 to -0.9) per year (about 0.10 population SD units per year). Participants with delirium showed significantly faster long-term cognitive change with an additional -0.4 GCP units (95% CI, -0.1 to -0.7) or -1.4 units per year (about 0.14 population SD units per year).

Conclusions and Relevance

This cohort study found that delirium was associated with a 40% acceleration in the slope of cognitive decline out to 72 months following elective surgery. Because this is an observational study, we cannot be sure whether delirium directly causes subsequent cognitive decline, or whether patients with preclinical brain disease are more likely to develop delirium. Future research is needed to understand the causal pathway between delirium and cognitive decline.

Development of a latent dementia index in the aging, demographics, and memory study: Validation and measurement invariance by sex

Latent variable models can create a latent dementia index (LDI) using cognitive and functional ability to approximate dementia likelihood. The LDI approach has been applied across diverse cohorts. It is unclear whether sex affects its measurement properties. We use Wave A (2001-2003) of the Aging, Demographics, and Memory Study (n = 856). Multiple group confirmatory factor analysis (CFA) was used to test measurement invariance (MI) using informant-reported functional ability and cognitive performance tasks, which we group into verbal, nonverbal, and memory. Partial scalar invariance was found, allowing for testing sex differences in LDI means (MDiff = 0.38). The LDI correlated with consensus panel dementia diagnosis, Mini-Mental State Examination (MMSE), and dementia risk factors (low education, advanced age, and apolipoprotein ε4 [APOE-ε4] status) for men and women. The LDI validly captures dementia likelihood to permit estimation of sex differences. LDI sex differences indicate higher dementia likelihood in women, potentially due to social, environmental, and biological factors.

CERAD (Consortium to Establish a Registry for Alzheimer's Disease) Neuropsychology Assessment Battery: 35 Years and Counting

BACKGROUND

In 1986, the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) was mandated to develop a brief neuropsychological assessment battery (CERAD-NAB) for AD, for uniform neuropsychological assessment, and information aggregation. Initially used across the National Institutes of Aging-funded Alzheimer's Disease Research Centers, it has become widely adopted wherever information is desired on cognitive status and change therein, particularly in older populations.

OBJECTIVE

Our purpose is to provide information on the multiple uses of the CERAD-NAB since its inception, and possible further developments.

METHODS

Since searching on "CERAD neuropsychological assessment battery" or similar terms missed important information, "CERAD" alone was entered into PubMed and SCOPUS, and CERAD-NAB use identified from the resulting studies. Use was sorted into major categories, e.g., psychometric information, norms, dementia/differential dementia diagnosis, epidemiology, intervention evaluation, genetics, etc., also translations, country of use, and alternative data gathering approaches.

RESULTS

CERAD-NAB is available in ∼20 languages. In addition to its initial purpose assessing AD severity, CERAD-NAB can identify mild cognitive impairment, facilitate differential dementia diagnosis, determine cognitive effects of naturally occurring and experimental interventions (e.g., air pollution, selenium in soil, exercise), has helped to clarify cognition/brain physiology-neuroanatomy, and assess cognitive status in dementia-risk conditions. Surveys of primary and tertiary care patients, and of population-based samples in multiple countries have provided information on prevalent and incident dementia, and cross-sectional and longitudinal norms for ages 35-100 years.

CONCLUSION

CERAD-NAB has fulfilled its original mandate, while its uses have expanded, keeping up with advances in the area of dementia.

Association of Religious Service Attendance and Neuropsychiatric Symptoms, Cognitive Function, and Sleep Disturbances in All-Cause Dementia

Commonly reported in dementia, neuropsychiatric symptoms (NPS), cognitive decline, and sleep disturbances indicate dementia progression. With the growing dementia burden, identifying protective factors that may slow dementia progression is increasingly essential. Religion and spirituality are associated with better mental and physical health, yet few studies have been reported in older adults with dementia. This study examines associations between religious service attendance and symptoms of dementia progression. Using data from the Health and Retirement Study in 2000, 2006, and 2008 and the sub-study, Aging, Demographics, and Memory Study in 2001-2003, 2006-2007, and 2008-2009, we examined the association of religious attendance with neuropsychiatric symptoms, cognitive function, and sleep disturbances among U.S. older adults aged 70 years and older with all-cause dementia (N = 72) using Spearman's partial Rho correlation controlling for social interaction. Significant associations were identified for religious attendance and NPS (r_s (97) = -0.124, 95% CI [-0.129, -0.119], p < 0.0005); cognitive function, r_s (97) = -0.018, 95% CI [-0.023, -0.013], p < 0.001); and sleep disturbances, r_s (97) = -0.275, 95% CI [-0.280, -0.271], p < 0.0005). Beyond adjusting for social interaction, increased religious attendance was associated with lower NPS, better cognitive function, and fewer sleep disturbances. Clinical trials and longitudinal studies with a larger sample size examining religion and spirituality factors with dementia progression are warranted.

Cognitive decline among older adults with heart diseases before and during the COVID-19 pandemic: A longitudinal cohort study

Background

Little is known about the impact induced by the COVID-19 pandemic on the cognitive function of older adults with heart diseases. This study aimed to examine whether older adults with heart diseases suffered larger cognitive deterioration during the COVID-19 pandemic.

Methods

This study leveraged longitudinal data from the Health and Retirement Study (HRS), a nationally representative U.S. aging cohort with objective cognitive assessments measured before and during the pandemic. The interval from HRS waves 13 to 14 (April 2016 to June 2019) was defined as the pre-pandemic period to control the pre-existed cognitive difference between participants with and without heart diseases, and the interval from waves 14 to 15 (June 2019 to June 2021) was defined as the pandemic period. The HRS wave 14 survey was considered the baseline. The heart disease status was defined by a self-reported diagnosis. Linear mixed models were performed to evaluate and compare the cognitive differences during different periods.

Results

A total of 9,304 participants (women: 5,655, 60.8%; mean age: 65.8 ± 10.8 years) were included, and 2,119 (22.8%) had heart diseases. During the pre-pandemic period, there was no significant difference (-0.03, 95% CI: -0.22 to 0.15, P = 0.716) in the changes in global cognitive scores between participants with and without heart disease. During the pandemic period, a larger decreased change in the global cognitive score was observed in the heart disease group compared with the non-heart disease group (-0.37, 95% CI: -0.55 to -0.19, P < 0.001). An enlarged difference in global cognitive score was observed during the pandemic period (-0.33, 95% CI: -0.65 to -0.02, P = 0.036).

Conclusion

The findings demonstrated that the population with heart diseases suffered more cognitive decline related to the pandemic, underscoring the necessity to provide immediate cognitive monitoring and interventions for the population with heart diseases.

Estimating the Prevalence of Dementia in India Using a Semi-Supervised Machine Learning Approach

INTRODUCTION

Accurate estimation of dementia prevalence is essential for making effective public and social care policy to support individuals and families suffering from the disease. The purpose of this paper is to estimate the prevalence of dementia in India using a semi-supervised machine learning approach based on a large nationally representative sample.

METHODS

The sample of this study is adults 60 years or older in the wave 1 (2017-2019) of the Longitudinal Aging Study in India (LASI). A subsample in LASI received extensive cognitive assessment and clinical consensus ratings and therefore has diagnoses of dementia. A semi-supervised machine learning model was developed to predict the status of dementia for LASI participants without diagnoses. After obtaining the predictions, sampling weights and age standardization to the World Health Organization (WHO) standard population were applied to generate the estimate for prevalence of dementia in India.

RESULTS

The prevalence of dementia for those aged 60 years and older in India was 8.44% (95% CI: 7.89%-9.01%). The age-standardized prevalence was estimated to be 8.94% (95% CI: 8.36%-9.55%). The prevalence of dementia was greater for those who were older, were females, received no education, and lived in rural areas.

DISCUSSION

The prevalence of dementia in India may be higher than prior estimates derived from local studies. These prevalence estimates provide the information necessary for making long-term planning of public and social care policy. The semi-supervised machine learning approach adopted in this paper may also be useful for other large population aging studies that have a similar data structure.

Trends in prevalence, health disparities, and early detection of dementia: A 10-year nationally representative serial cross-sectional and cohort study

Objective

To identify trends in the prevalence of mild cognitive impairment (MCI) and dementia, and to determine risk factors associated with the early detection of dementia among U.S. middle-aged and older adults.

Methods

We used 10-year nationally representative longitudinal data from the Health and Retirement Study (HRS) (2006-2016). Adults aged 55 years or older were included to examine the trend. To identify the associated factors, adults aged 55 years or older in 2006 who developed MCI or dementia in subsequent waves until the 2016 wave were included. Early and late detection of dementia were identified using the Langa-Weir classification of cognitive function. Multivariate logistic regression models were used to identify factors associated with the early detection of dementia.

Results

The sample size for the analysis of the prevalence of MCI and dementia ranged from 14,935 to 16,115 in the six survey years, and 3,729 individuals were identified to determine associated factors of the early detection of dementia. Among them, participants aged 65 years or older accounted for 77.9%, and male participants accounted for 37.2%. The 10-year prevalence of MCI and dementia was 14.5 and 6.6%, respectively. We also found decreasing prevalence trends in MCI (from 14.9 to 13.6%) and dementia (from 7.4 to 6.0%) overall in the past decade. Using logistic regression controlling for the year, non-Hispanic black (MCI: OR = 2.83, P < 0.001; dementia: OR = 2.53, P < 0.001) and Hispanic (MCI: OR = 2.52, P < 0.001; dementia: OR = 2.62, P < 0.001) had a higher prevalence of both MCI and dementia than non-Hispanic white participants. In addition, men had a lower prevalence of MCI (OR = 0.94, P = 0.035) and dementia (OR = 0.84, P < 0.001) compared to women. Associated factors of the early detection of dementia include age, gender, race, educational attainment, stroke, arthritis diseases, heart problems, and pensions.

Conclusion

This study found a decreasing trend in the prevalence of MCI and dementia in the past decade and associated racial/ethnic and gender disparities among U.S. middle-aged and older adults. Healthcare policies and strategies may be needed to address health disparities in the prevalence and take the associated factors of the early detection of dementia into account in clinical settings.

Statistical harmonization of everyday functioning and dementia-related behavioral measures across nine surveys and trials

Introduction

Efforts to harmonize measures of everyday function and dementia-related behaviors are needed to synthesize across studies in dementia research. There have been some psychometric attempts to harmonize everyday function for secondary analysis, but far less for dementia-related behaviors.

Methods

Statistical co-calibration was performed to generate factor scores representing everyday function and dementia-related behaviors for participants with dementia. We evaluated convergent criterion validity of factor scores and mapped the scores onto established clinical instruments.

Results

Factor analyses of included items fit well to available data. Harmonized factors showed expected associations with the Global Clinical Dementia Rating (CDR) score, with greater impairment (higher Global CDR score) corresponding to higher (more severe) levels on factor scores.

Discussion

We used large, well-characterized samples to derive harmonized factors representing everyday functions and dementia-related behaviors. These harmonized factors can be used to tackle questions about dementia phenotypes which require either large samples or unique subpopulations.

The Influence of Cognitive Impairment on Postoperative Outcomes

OBJECTIVE

To examine differences in rates of elective surgery, postoperative mortality, and readmission by pre-existing cognitive status among Medicare beneficiaries undergoing surgery.

BACKGROUND

MCI is common among older adults, but the impact of MCI on surgical outcomes is understudied.

METHODS

We conducted a retrospective cohort study of individuals ≥65 who underwent surgery between 2001 and 2015 using data from the nationally-representative Health and Retirement Study linked with Medicare claims. Cognitive status was assessed by the modified telephone interview for cognitive status score and categorized as normal cognition (score: 12-27), MCI (7-11), and dementia (<7). Outcomes were 30- and 90-day postoperative mortality and readmissions. We used Cox proportional hazard models to estimate the risk of each outcome by cognition, adjusting for patient characteristics.

RESULTS

In 6,590 patients, 69.9% had normal cognition, 20.1% had MCI, and 9.9% had dementia. Patients with MCI (79.9%) and dementia (73.6%) were less likely to undergo elective surgery than patients with normal cognition (85.9%). Patients with MCI had similar postoperative mortality and readmissions rates as patients with normal cognition. However, patients with dementia had significantly higher postoperative 90-day mortality (5.2% vs 8.4%, P = 0.002) and readmission rates (13.9% vs 17.3%, P = 0.038).

CONCLUSION

Patients with self-reported MCI are less likely to undergo elective surgery but have similar postoperative outcomes compared with patients with normal cognition. Despite the variability of defining MCI, our findings suggest that MCI may not confer additional risk for older individuals undergoing surgery, and should not be a barrier for surgical care.

Successful aging after elective surgery II: Study design and methods

BACKGROUND

The Successful Aging after Elective Surgery (SAGES) II study was designed to increase knowledge of the pathophysiology and linkages between delirium and dementia. We examine novel biomarkers potentially associated with delirium, including inflammation, Alzheimer's disease (AD) pathology and neurodegeneration, neuroimaging markers, and neurophysiologic markers. The goal of this paper is to describe the study design and methods for the SAGES II study.

METHODS

The SAGES II study is a 5-year prospective observational study of 400-420 community dwelling persons, aged 65 years and older, assessed prior to scheduled surgery and followed daily throughout hospitalization to observe for development of delirium and other clinical outcomes. Delirium is measured with the Confusion Assessment Method (CAM), long form, after cognitive testing. Cognitive function is measured with a detailed neuropsychologic test battery, summarized as a weighted composite, the General Cognitive Performance (GCP) score. Other key measures include magnetic resonance imaging (MRI), transcranial magnetic stimulation (TMS)/electroencephalography (EEG), and Amyloid positron emission tomography (PET) imaging. We describe the eligibility criteria, enrollment flow, timing of assessments, and variables collected at baseline and during repeated assessments at 1, 2, 6, 12, and 18 months.

RESULTS

This study describes the hospital and surgery-related variables, delirium, long-term cognitive decline, clinical outcomes, and novel biomarkers. In inter-rater reliability assessments, the CAM ratings (weighted kappa = 0.91, 95% confidence interval, CI = 0.74-1.0) in 50 paired assessments and GCP ratings (weighted kappa = 0.99, 95% CI 0.94-1.0) in 25 paired assessments. We describe procedures for data quality assurance and Covid-19 adaptations.

CONCLUSIONS

This complex study presents an innovative effort to advance our understanding of the inter-relationship between delirium and dementia via novel biomarkers, collected in the context of major surgery in older adults. Strengths include the integration of MRI, TMS/EEG, PET modalities, and high-quality longitudinal data.

Biomarkers and Risk Assessment of Alzheimer's Disease in Low- and Middle-Income Countries

Dementia is a chronic syndrome which is common among the elderly and is associated with significant morbidity and mortality for patients and their caregivers. Alzheimer's disease (AD), the most common form of clinical dementia, is biologically characterized by the deposition of amyloid-β plaques and neurofibrillary tangles in the brain. The onset of AD begins decades before manifestation of symptoms and clinical diagnosis, underlining the need to shift from clinical diagnosis of AD to a more objective diagnosis using biomarkers. Having performed a literature search of original articles and reviews on PubMed and Google Scholar, we present this review detailing the existing biomarkers and risk assessment tools for AD. The prevalence of dementia in low- and middle-income countries (LMICs) is predicted to increase over the next couple of years. Thus, we aimed to identify potential biomarkers that may be appropriate for use in LMICs, considering the following factors: sensitivity, specificity, invasiveness, and affordability of the biomarkers. We also explored risk assessment tools and the potential use of artificial intelligence/machine learning solutions for diagnosing, assessing risks, and monitoring the progression of AD in low-resource settings. Routine use of AD biomarkers has yet to gain sufficient ground in clinical settings. Therefore, clinical diagnosis of AD will remain the mainstay in LMICs for the foreseeable future. Efforts should be made towards the development of low-cost, easily administered risk assessment tools to identify individuals who are at risk of AD in the population. We recommend that stakeholders invest in education, research and development targeted towards effective risk assessment and management.

Patterns of sleep disturbances across stages of cognitive decline

OBJECTIVES

The purpose of this study was to investigate insomnia symptoms and excessive sleep/sluggishness across stages of cognitive decline (cognitively normal [CN], Cognitively Impairment, Not Demented [CIND], dementia) in a large, racially/ethnically diverse sample of older adults (70+) in the US. We also examined whether sleep disturbances at baseline predicted conversion to CIND or dementia at follow-up.

METHODS

In this secondary analysis of the Aging, Demographics, and Memory Study (ADAMS) supplement of the Health Retirement Study, we analyzed patterns of informant-reported insomnia and excessive sleep symptoms among three groups of older adults (n = 846): CN, CIND, and dementia.

RESULTS

CIND adults were significantly more likely to have informant-reported insomnia symptoms than those in the CN group (p = 0.013). This was driven by a significant race/ethnicity-by-insomnia interaction with diagnostic status (p = 0.029), such that CIND Black and Hispanic older adults had increased insomnia symptom rates compared to CN, whereas White adults had similar insomnia symptoms across diagnostic status. Across all racial/ethnic groups, the prevalence of excessive sleep symptoms increased stepwise from CN to CIND to dementia (p < 0.001). Overall, insomnia symptoms at baseline predicted conversion from CN to CIND (p < 0.001, OR = 0.288; 95% CI: 0.143-0.580) at 4-year (approximate) follow-up; there was no relationship between baseline insomnia or excessive sleep/sluggishness symptoms and conversion from CIND to dementia.

DISCUSSION/CONCLUSION

This study provides evidence for the increased risk of insomnia symptoms among Hispanic and Black older adults with CIND, and indicates that insomnia symptoms may be associated with increased risk for development of cognitive impairment.

The Interplay Among Natural Menopause, Insomnia, and Cognitive Health: A Population-Based Study

PURPOSE

The interrelationships among age at menopause, sleep, and brain health have been insufficiently studied. This study sought to examine the influence of age at natural menopause and insomnia symptoms on long-term cognitive function among US women.

PATIENTS AND METHODS

Our study included a nationally representative cohort of US adults age 50+ from the Health and Retirement Study (2008-2018). We restricted this cohort to 5880 women age 50+, from a diverse racial and ethnic groups. Age at menopause was retrieved from baseline (2008) for women having natural menopause. Five questions were used to identify women with insomnia symptoms (2010 and 2012): trouble falling asleep, nighttime awakenings, early morning awakenings, feelings of nonrestorative sleep, and use of sleep aids. A battery of four neuropsychological tests was conducted biennially (years) to evaluate cognitive function. Longitudinal associations between age at natural menopause and cognitive function were estimated with mixed effects models with a random intercept. Insomnia symptoms were examined as potential mediators or modifiers in the pathway between age at menopause and cognition.

RESULTS

One year earlier in age at menopause was associated with a 0.49 lower mean in composite cognitive score, in any given survey year (adjusted p = 0.002). Earlier age at menopause was associated with higher risk of developing insomnia symptoms (eg, trouble falling asleep OR = 0.97; 95% CI: 0.96, 0.99), and insomnia symptoms were associated with worse cognitive performance (eg, trouble falling asleep, beta = -0.5, p-value = 0.02). Therefore, insomnia symptoms could potentially mediate the association between age at natural menopause and cognition.

CONCLUSION

Earlier age at menopause is associated with a lower score in cognitive performance. This association may be mediated by insomnia symptoms. Our findings spotlight that among women who experience early menopause, there is the need for studies of sleep-based interventions to mitigate cognitive decline.

COVID-19 pandemic experiences of older adults with dementia in community and residential care settings: Results from a US national survey

Introduction

Investigations into consequences of the US COVID-19 pandemic for older adults with dementia have been limited.

Methods

We used the National Health and Aging Trends Study to examine self-reported COVID-19 infection; measures taken to limit its spread; social, behavioral, and emotional responses to the pandemic; and changes in health-care use and provider communication. We compared adults aged ≥70 with and without dementia in community and residential care settings.

Results

In residential care settings, infection was substantially higher and social contact less common for those with dementia. In community and residential care settings, those with dementia had 2 to 3 times the odds of reporting sleeping more often. In residential care settings, those with dementia were less likely to put off care and more likely to start telehealth.

Discussion

Findings highlight the disproportionate social and behavioral consequences of the COVID-19 pandemic for those living with dementia, particularly in residential care settings.

HIGHLIGHTS

Data are from the nationally representative National Health and Aging Trends Study.COVID-19 infection was higher in residential care settings for those with dementia.Social contact was less common for those with dementia in residential care.Pandemic-related coping behaviors differed by dementia and residential status.In residential care, those with dementia were less likely to delay health care.

Interactions between the apolipoprotein E4 gene and modifiable risk factors for cognitive impairment: a nationally representative panel study

BACKGROUND

Few studies using rigorous clinical diagnosis have considered whether associations with cognitive decline are potentiated by interactions between genetic and modifiable risk factors. Given the increasing burden of cognitive impairment (CI) and dementia, we assessed whether Apolipoprotein E ε4 (APOE4) genotype status modifies the association between incident CI and key modifiable risk factors .

METHODS

Older adults (70+) in the US were included. APOE4 status was genotyped. Risk factors for CI were self-reported. Cognitive status (normal, CI, or dementia) was assigned by clinical consensus panel. In eight separate Cox proportional hazard models, we assessed for interactions between APOE4 status and other CI risk factors.

RESULT

The analytical sample included 181 participants (mean age 77.7 years; 45.9% male). APOE4 was independently associated with a greater hazard of CI in each model (Hazard Ratios [HR] between 1.81-2.66, p < 0.05) except the model evaluating educational attainment (HR 1.65, p = 0.40). The joint effects of APOE4 and high school education or less (HR 2.25, 95% CI: 1.40-3.60, p < 0.001), hypertension (HR 2.46, 95% CI: 1.28-4.73, p = 0.007), elevated depressive symptoms (HR 5.09, 95% CI: 2.59-10.02, p < 0.001), hearing loss (HR 3.44, 95% CI: 1.87-6.33, p < 0.0001), vision impairment (HR 5.14, 95% CI: 2.31-11.43, p < 0.001), smoking (HR 2.35, 95% CI: 1.24-4.47, p = 0.009), or obesity (HR 3.80, 95% CI: 2.11-6.85, p < 0.001) were associated with the hazard of incident CIND (compared to no genetic or modifiable risk factor) in separate models. The joint effect of Apolipoprotein ε4 and type 2 diabetes was not associated with CIND (HR 1.58, 95% CI: 0.67-2.48, p = 0.44).

DISCUSSION

The combination of APOE4 and selected modifiable risk factors conveys a stronger association with incident CI than either type of risk factor alone.

Future Directions for the HRS Harmonized Cognitive Assessment Protocol

In the absence of effective pharmacological treatment to halt or reverse the course of Alzheimer's disease and related dementias (ADRDs), population-level research on the modifiable determinants of dementia risk and outcomes for those living with ADRD is critical. The Harmonized Cognitive Assessment Protocol (HCAP), fielded in 2016 as part of the U.S. Health and Retirement Study (HRS) and multiple international counterparts, has the potential to play an important role in such efforts. The stated goals of the HCAP are to improve our ability to understand the determinants, prevalence, costs, and consequences of cognitive impairment and dementia in the U.S. and to support cross-national comparisons. The first wave of the HCAP demonstrated the feasibility and value of the more detailed cognitive assessments in the HCAP compared to the brief cognitive assessments in the core HRS interviews. To achieve its full potential, we provide eight recommendations for improving future iterations of the HCAP. Our highest priority recommendation is to increase the representation of historically marginalized racial/ethnic groups disproportionately affected by ADRDs. Additional recommendations relate to the timing of the HCAP assessments; clinical and biomarker validation data, including to improve cross-national comparisons; dropping lower performing items; enhanced documentation; and the addition of measures related to caregiver impact. We believe that the capacity of the HCAP to achieve its stated goals will be greatly enhanced by considering these changes and additions.

Treatment preferences among adults with normal cognition and cognitive impairment

BACKGROUND

Although patient participation in treatment decisions is important for preference-concordant care delivery, it is largely unknown how cognitive impairment influences treatment preferences. We investigated whether treatment preferences for the care of serious illness differ between adults with and without cognitive impairment in hypothetical clinical scenarios.

METHODS

Data from the 2018 Health and Retirement Study were used. The sample included 1291 self-respondents (201 respondents with cognitive impairment, and 1090 with normal cognition). We examined treatment preferences for life-extending, limited, and comfort care options in two hypothetical clinical scenarios where the respondent imagines a patient with (1) good physical health with severe cognitive impairment consistent with dementia; and (2) with physical impairment due to a heart attack, but normal cognition. Respondents specified whether they were unsure, or if they would want or not want each treatment option. Linear probability models were used to compare treatment preferences by cognitive status.

RESULTS

Respondents with cognitive impairment were more likely to report that they were unsure about treatment options across both clinical scenarios compared to those with normal cognition. For the limited treatment option, cognitive impairment was associated with a lower rate of expressing a treatment preference by 7.3 (p = 0.070) and 8.5 (p = 0.035) percentage points for dementia and heart attack scenarios, respectively. Among those who articulated preferences, cognitive impairment was associated with a higher rate of preference for life-extending treatment in both dementia (30.1% vs. 20.0%, p = 0.044) and heart attack scenarios (30.0% vs. 20.2%, p = 0.033).

CONCLUSIONS

Compared to those with normal cognition, cognitive impairment was associated with greater uncertainty about treatment preferences and higher rates of aggressive care preferences among those who specified preferences. Further research should assess whether preferences for aggressive care become more common as cognition declines in order to improve preference-concordant care delivery for patients with cognitive impairment.