Early-versus Late-Onset Alzheimer Disease: Long-Term Functional Outcomes, Nursing Home Placement, and Risk Factors for Rate of Progression

Clinical and demographic factors modify the association between plasma phosphorylated tau-181 and cognition

INTRODUCTION

Plasma phosphorylated tau181 (p-tau181) associations with global cognition and memory are clear, but the link between p-tau181 with other cognitive domains and subjective cognitive decline (SCD) across the clinical spectrum of Alzheimer's disease (AD) and how this association changes based on genetic and demographic factors is poorly understood.

METHODS

Participants were drawn from the Alzheimer's Disease Neuroimaging Initiative and included 1185 adults aged >55 years with plasma p-tau181 and neuropsychological test data. Linear regression models related plasma p-tau181 to neuropsychological composite and SCD scores with follow-up models examining plasma p-tau181 interactions with cognitive diagnosis, APOE ε4 carrier status, age, and sex on cognitive outcomes.

RESULTS

Higher plasma p-tau181 was associated with worse memory, executive functioning, and language abilities, and greater informant-reported SCD. Visuospatial abilities and self-report SCD were not associated with plasma p-tau181. Associations were generally stronger in MCI or dementia, APOE ε4 carriers, women, and younger participants.

DISCUSSION

Higher levels of plasma p-tau181 are associated with worse neuropsychological test performance across multiple cognitive domains; however, these associations vary based on disease stage, genetic risk status, age, and sex.

Attitudes about involvement in hypothetical clinical trial protocols in Mexican and Mexican-American at risk for autosomal dominant Alzheimer's disease

BACKGROUND

The enrollment into clinical trials of persons at risk for autosomal dominant Alzheimer's disease (ADAD) in whom the onset of disease can be accurately predicted facilitates the interpretation of outcomes (e.g., biomarkers, treatment efficacy). Attitudes toward involvement in such studies are biased by intrinsic cultural and social characteristics. Our objective was to study how demographic factors such as country of residence, age, sex, schooling, parenthood, and urbanization affect attitudes towards participation in hypothetical clinical trials in Mexican families at risk for ADAD living either in Mexico or in the United States.

METHODS

Participants were 74 members of different families known to harbor an ADAD mutation living in Mexico (n = 50) or in the United States (n = 24). Participants were asked, in a written questionnaire, their interest in participating in four hypothetical clinical trial scenarios of increasing perceived invasiveness. The questionnaire then asked about their willingness should there be a 50% chance of being assigned to a placebo group. The influences of demographic variables on decisions were performed using Wilcoxon rank-sum for continuous variables and Fisher's exact test for categorical variables.

RESULTS

Participants who live in Mexico, who have or plan to have children, who do not attend or do not plan to attend school, and who live in rural areas gave more positive responses regarding their willingness to participate compared to those living in the U.S. The 50% chance of being in a placebo group increased the willingness to participate for family members living in Mexico. The main reason for participation was to help future generations, while the main reasons for refusal were not wanting to undergo genetic testing and consideration of adverse effects.

CONCLUSIONS

We found a higher level of willingness to participate in clinical trials among persons living in rural Mexico and our data suggest that altruism towards future generations is a major motivation, though this was balanced against concerns regarding side effects. Our results emphasize the importance of sharing information and assessing its understanding in potential participants with diverse backgrounds in the nature of ADAD and regarding the design of clinical trials prior to their enrollment in such studies.

Gender Differences in Demographic and Pharmacological Factors in Patients Diagnosed with Late-Onset of Alzheimer’s Disease

Background: Whether gender differences exist in late-onset of Alzheimer’s disease (LOAD) treated with cholinesterase inhibitors (ChEIs) is not fully understood. This study investigated demographic and pharmacological characteristics in LOAD patients to determine gender differences in LOAD patients treated with ChEIs alone and ChEIs with other medications. Methods: This 5-year retrospective data analysis included 9290 LOAD AD patients with 2949 men patients and 6341 women. Potential predictors of demographic and pharmacological characteristics associated gender differences in patients treated with and without ChEIs therapy were determined using univariate analysis, while multivariable models adjusted for demographic and pharmacological variables. Results: In the adjusted analysis, men patients with LOAD that presented with a history of alcohol use (ETOH) (OR = 1.339, 95% CI, 1.072–1.672, p = 0.010), treated with second generation antipsychotics (SGAs) (OR = 1.271, 95% CI, 1.003–1.610, p = 0.047), citalopram (OR = 5.103, 95% CI, 3.423–7.607, p < 0.001), memantine (OR = 4.409, 95% CI, 3.704–5.249, p < 0.001), and buspirone (OR = 2.166, 95% CI, 1.437–3.264, p < 0.001) were more likely to receive ChEIs therapy, whereas older men were less likely to be treated with ChEIs therapy. Women who were African Americans (OR = 1.387, 95% CI, 1.168–1.647, p < 0.001), that received memantine (OR = 3.412, 95% CI, 3.034–3.837, p < 0.001), selective serotonin reuptake inhibitor (SSRIs) (OR = 1.143, 95% CI, 1.016–1.287, p = 0.026), and a history of ETOH (OR = 2.109, 95% CI, 1.724–2.580, p < 0.001) were more likely to receive ChEIs therapy, whereas older women were less likely to receive ChEIs therapy. Conclusion: In both men and women patients, those with increasing age were less likely to be treated with ChEI therapy, while patients treated with memantine were also likely to receive ChEI therapy. Our findings highlight the importance for clinicians to optimize ChEI in LOAD to improve treatment effectiveness and eliminate gender differences in ChEI therapy.

Baseline MRI atrophy predicts 2-year cognitive outcomes in early-onset Alzheimer's disease

BACKGROUND

MRI atrophy predicts cognitive status in AD. However, this relationship has not been investigated in early-onset AD (EOAD, < 65 years) patients with a biomarker-based diagnosis.

METHODS

Forty eight EOAD (MMSE ≥ 15; A + T + N +) and forty two age-matched healthy controls (HC; A - T - N -) from a prospective cohort underwent full neuropsychological assessment, 3T-MRI scan and lumbar puncture at baseline. Participants repeated the cognitive assessment annually. We used linear mixed models to investigate whether baseline cortical thickness (CTh) or subcortical volume predicts two-year cognitive outcomes in the EOAD group.

RESULTS

In EOAD, hemispheric CTh and ventricular volume at baseline were associated with global cognition, language and attentional/executive functioning 2 years later (p < 0.0028). Regional CTh was related to most cognitive outcomes (p < 0.0028), except verbal/visual memory subtests. Amygdalar volume was associated with letter fluency test (p < 0.0028). Hippocampal volume did not show significant associations.

CONCLUSION

Baseline hemispheric/regional CTh, ventricular and amygdalar volume, but not the hippocampus, predict two-year cognitive outcomes in EOAD.

[Predictors of Admission to Nursing Home in Care-Dependent People - A Longitudinal Secondary Data Analysis]

OBJECTIVE

To determine predictors of admission to nursing home by means of secondary data analysis of German statutory health insurance claims data and care needs assessments.

MATERIALS AND METHODS

A retrospective longitudinal analysis was conducted covering the period 2006-2016 and using routine data. Health insurance data and care needs assessment data for people who became care dependent in 2006 and who lived in their own homes were merged. Cox regression analyses were conducted to identify predictors of admission to a nursing home.

RESULTS

The study population comprised 48,892 persons. Dementia, cancer of the brain, cognitive impairment, antipsychotics prescriptions, hospitalized fractures, hospital stays over ten days, and higher age had the highest hazard ratios among the predictors.

CONCLUSIONS

Knowledge about the predictors serves to sensitize health care professionals in the care of people in need of care. It facilitates identification of care needs in community-dwelling persons at an increased risk of admission to a nursing home.

Factors associated with slow progression of cognitive impairment following first dementia diagnosis

OBJECTIVES

To investigate the extent to which slow progression of dementia after diagnosis might be predicted from routine longitudinal healthcare data, in order to clarify characteristics of people who experience this outcome.

METHODS

A retrospective observational study was conducted using data from the South London and Maudsley NHS Foundation Trust Biomedical Research Centre Case Register. This study included all patients receiving a first dementia diagnosis between 2006 and 2017, restricted to those with a baseline Mini-Mental State Examination (MMSE) score within 6 months of initial diagnosis of dementia and at least one MMSE score after 3 years post-diagnosis. Slow progression was defined as a change in MMSE score of -1, 0 or an increase at the follow-up point. This group was compared to the remainder with an MMSE decline of -2 or more.

RESULTS

Overall, 682 patients with slow progression were compared to 1045 with faster progression. In the confounder-adjusted multivariate logistic regression model, slow progression was more likely in younger patients (age 65-74 years; odds ratio: 1.18; 95% confidence intervals: 1.04-1.37), males (1.24; 1.01-1.53), those with moderate or severe dementia according to MMSE, patients with mixed-type dementia (2.06; 1.11-3.82) compared to Alzheimer's disease and less likely in those receiving acetylcholinesterase inhibitor (AChEI) treatment (0.57; 0.46-0.71).

CONCLUSION

Slow dementia progression after diagnosis was common in patients with mixed Alzheimer's and vascular dementia, younger age, males and non-receipt of AChEIs, possibly suggesting non-Alzheimer pathologies and clarifying such predictors is important, as there is currently very limited information on which to base prognosis estimates in post-diagnosis counselling.

Modifiable, Non-Modifiable, and Clinical Factors Associated with Progression of Alzheimer's Disease

There is an extensive literature relating to factors associated with the development of Alzheimer's disease (AD), but less is known about factors which may contribute to its progression. This review examined the literature with regard to 15 factors which were suggested by PubMed search to be positively associated with the cognitive and/or neuropathological progression of AD. The factors were grouped as potentially modifiable (vascular risk factors, comorbidities, malnutrition, educational level, inflammation, and oxidative stress), non-modifiable (age at clinical onset, family history of dementia, gender, Apolipoprotein E ɛ4, genetic variants, and altered gene regulation), and clinical (baseline cognitive level, neuropsychiatric symptoms, and extrapyramidal signs). Although conflicting results were found for the majority of factors, a positive association was found in nearly all studies which investigated the relationship of six factors to AD progression: malnutrition, genetic variants, altered gene regulation, baseline cognitive level, neuropsychiatric symptoms, and extrapyramidal signs. Whether these or other factors which have been suggested to be associated with AD progression actually influence the rate of decline of AD patients is unclear. Therapeutic approaches which include addressing of modifiable factors associated with AD progression should be considered.

Impact of the Physician Orders for Life-Sustaining Treatment (POLST) Program Maturity Status on the Nursing Home Resident's Place of Death

The Physician Orders for Life-Sustaining Treatment (POLST) program was developed to enhance quality of care delivered at End-of-Life (EoL). Although positive impacts of the POLST program have been identified, the association between a program maturity status and nursing home resident's likelihood of dying in their current care settings remain unanswered. This study aims to evaluate the impact of the POLST program maturity status on nursing home residents' place of death. Using multiple national-level datasets, we examined total 595,152 residents and their place of death. The result showed that the long-stay residents living in states where the program was mature status had 12% increased odds of dying in nursing homes compared that of non-conforming status. Individuals residing in states with developing program status showed 11% increase in odds of dying in nursing homes. The findings demonstrate that a well-structured and well-disseminated POLST program, combined with a continued effort to meet high standards of quality EoL care, can bring out positive health outcomes for elderly patients residing in care settings.

[Influencing factors for nursing home admission in case of pre-existing need of care - a systematic review]

INTRODUCTION

Knowledge about predictors of nursing home placement is highly relevant. If they are known, targeted interventions such as counselling can help prevent or delay relocation to a nursing home. Above all, preventive and structural measures can target influenceable predictors. The aim of the review was to map predictors of nursing home admission and thus the permanent stay in inpatient long-term care for the target group of people with a pre-existing need for care.

METHODS

A systematic literature search in the databases The Cochrane Library, PubMed, CINAHL, GeroLit and CareLit® was conducted in September 2017. Longitudinal studies with quantitative analyses were included. The methodological quality was assessed using the Newcastle-Ottawa Scale.

RESULTS

45 cohort studies were included. 21 studies examined study populations with need for care, in 24 studies the care status was unclear. A variety of predictors of nursing home admission with at least one-and-a-half times higher risk for both study populations could be identified, including higher age, dementia, underweight, higher age of caregiver, psychiatric symptoms, smoking status, ethnicity, challenging behaviour in people with dementia, higher number of hospitalizations and lower level of life satisfaction.

DISCUSSION

All the predictors identified are relevant to people in need of care. No predictors for the study population with need of care could be identified that are particularly important in contrast to persons with an unclear care status. However, the quality of studies among people with care and support needs is limited compared to studies targeting people with unclear care status.

CONCLUSIONS

Many factors seem to predict the admission to a nursing facility. For the first time, these factors are listed in this systematic review for the target group of people in need of care. Interventions or preventive measures based on known influenceable predictors can help prevent or delay nursing home admission.

Risk of Alzheimer's Disease in Cancer Patients: Analysis of Mortality Data from the US SEER Population-Based Registries

Previous studies have reported an inverse association between cancer and Alzheimer's disease (AD), which are leading causes of human morbidity and mortality. We analyzed the SEER (Surveillance, Epidemiology, and End Results) data to estimate the risk of AD death in (i) cancer patients relative to reference populations stratified on demographic and clinical variables, and (ii) female breast cancer (BC) patients treated with chemotherapy or radiotherapy, relative to those with no/unknown treatment status. Our results demonstrate the impact of race, cancer type, age and time since cancer diagnosis on the risk of AD death in cancer patients. While the risk of AD death was decreased in white patients diagnosed with various cancers at 45 or more years of age, it was increased in black patients diagnosed with cancers before 45 years of age (likely due to early onset AD). Chemotherapy decreased the risk of AD death in white women diagnosed with BC at the age of 65 or more, however radiotherapy displayed a more complex pattern with early decrease and late increase in the risk of AD death during a prolonged time interval after the treatment. Our data point to links between molecular mechanisms involved in cancer and AD, and to the potential applicability of some anti-cancer treatments against AD.

Early-onset Alzheimer Disease and Its Variants

PURPOSE OF REVIEW

Early-onset Alzheimer disease (AD) is defined as having an age of onset younger than 65 years. While early-onset AD is often overshadowed by the more common late-onset AD, recognition of the differences between early- and late-onset AD is important for clinicians.

RECENT FINDINGS

Early-onset AD comprises about 5% to 6% of cases of AD and includes a substantial percentage of phenotypic variants that differ from the usual amnestic presentation of typical AD. Characteristics of early-onset AD in comparison to late-onset AD include a larger genetic predisposition (familial mutations and summed polygenic risk), more aggressive course, more frequent delay in diagnosis, higher prevalence of traumatic brain injury, less memory impairment and greater involvement of other cognitive domains on presentation, and greater psychosocial difficulties. Neuroimaging features of early-onset AD in comparison to late-onset AD include greater frequency of hippocampal sparing and posterior neocortical atrophy, increased tau burden, and greater connectomic changes affecting frontoparietal networks rather than the default mode network.

SUMMARY

Early-onset AD differs substantially from late-onset AD, with different phenotypic presentations, greater genetic predisposition, and differences in neuropathologic burden and topography. Early-onset AD more often presents with nonamnestic phenotypic variants that spare the hippocampi and with greater tau burden in posterior neocortices. The early-onset AD phenotypic variants involve different neural networks than typical AD. The management of early-onset AD is similar to that of late-onset AD but with special emphasis on targeting specific cognitive areas and more age-appropriate psychosocial support and education.

Effect of Physical Activity on the Progression of Alzheimer's Disease: The Clinical Research Center for Dementia of South Korea Study

BACKGROUND

There is a lack of research on the effects of physical activity (PA) on the progression of Alzheimer's disease (AD).

OBJECTIVES

We investigated whether PA is associated with progression of dementia and mortality in AD.

METHODS

In the present study, 934 patients with mild-to-moderate AD were included. PA was evaluated using a questionnaire written by the caregiver. The outcome measures were the Clinical Dementia Rating-Sum of Boxes (CDR-SB), Seoul-Instrumental Activities of Daily Living (S-IADL), Caregiver-Administered Neuropsychiatric Inventory (CGA-NPI), a global composite score of neuropsychological subtests, and mortality. They were evaluated annually and received a maximum of three follow-up examinations.

RESULTS

Between-group differences compared with the no PA group in the change of CDR-SB scores were -0.431 (95% CI = -0.824∼-0.039; p = 0.031) for the moderate PA group (150-750 minutes per week of moderate intensity PA), and -1.148 (-1.656∼-0.639; p < 0.001) for the high PA group (>750 minutes per week). As PA increased, there was a significant trend to slow the rate of increase in the CDR-SB, S-IADL, and CGA-NPI scores. The patients with ≥150 minutes per week for each of non-recreational and recreational PAs had a lower risk of mortality compared to those with <150 minutes per week for each of the PAs (hazard ratio 0.22, 95% CI = 0.05∼0.88; p = 0.033).

CONCLUSION

More PA is associated with slower progression of dementia severity, functional decline, and abnormal behavior, and with a lower risk of mortality in AD.

Family caregivers' and professionals' stigmatic experiences with persons with early-onset dementia: a qualitative study

OBJECTIVES

Recently, research has focused on understanding the needs of persons with early-onset dementia and their family caregivers who often experience stigmatic beliefs. However, to date, research has not provided a thorough and deep understanding of the stigma formation process and its implications for this population. Thus, the aim of the present study was to explore the stigma formation process as experienced by family members as informal caregivers of persons with early-onset dementia, and professionals as formal caregivers who are involved in the development, management and provision of services.

METHOD

We conducted three focus groups with 16 participants, including spouses of a person with early-onset dementia and professionals. The focus groups' transcripts were analysed following a thematic analysis procedure.

RESULTS

Results indicated that both family members and professionals encounter stigmatic experiences because of their association with younger persons with dementia. Lack of knowledge emerged as the main antecedent and emotional burden as the main consequence of stigma.

CONCLUSION

Stigmatic experiences emerged as a pervasive and complex phenomenon among formal and informal caregivers of persons with early-onset dementia, suggesting the need to developing a comprehensive and integrated approach to reduce them at the individual, professional and societal levels.

Evaluating the Role of Microglial Cells in Clearance of Aβ from Alzheimer's Brain

Ever increasing incidence of Alzheimer's diseases (AD) has been reported all over the globe, and practically no drug is currently available for its treatment. In the past 15 years, not a single drug came out of clinical trials. The researchers have yet to discover a drug that could specifically target AD; in fact, the drugs that are about to launch in the global market either belong to natural compounds or are already approved drugs targeting other diseases. So, we need to shift our focus on finding novel targets which are more specific and could either detect or inhibit the disease progression at a very early stage. Microglia are the only resident innate immune cells of the brain that are originated from erythromyeloid progenitors. They migrate to the brain during early embryonic development, although their number is less (∼5 to 10%), but they could act as guardians of the brain. It has been shown that the extracellular deposits of Aβ are continuously phagocytosed by microglia in healthy individuals, but this ability would decrease with age and lead to development of AD. In this review, we have explored the possibility of whether microglial cells could be utilized as an early predictor of the AD progression. Here, we discuss the innate immune response of microglial cells, the factors affecting microglia response, microglial receptors to which Aβ could bind, and microglial phenotype markers. Last, we conclude with a list of available AD therapeutics along with their mechanism.

Early- versus late-onset Alzheimer's disease in clinical practice: cognitive and global outcomes over 3 years

BACKGROUND

Whether age at onset influences Alzheimer's disease (AD) progression and the effectiveness of cholinesterase inhibitor (ChEI) therapy is not clear. We aimed to compare longitudinal cognitive and global outcomes in ChEI-treated patients with early-onset Alzheimer's disease (EOAD) versus late-onset Alzheimer's disease (LOAD) in clinical practice.

METHODS

This 3-year, prospective, observational, multicentre study included 1017 participants with mild to moderate AD; 143 had EOAD (age at onset < 65 years) and 874 had LOAD (age at onset ≥ 65 years). At baseline and semi-annually, patients were assessed using cognitive, global and activities of daily living (ADL) scales, and the dose of ChEI was recorded. Potential predictors of decline were analysed using mixed-effects models.

RESULTS

Six-month response to ChEI therapy and long-term prognosis in cognitive and global performance were similar between the age-at-onset groups. However, deterioration was significantly faster when using the Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog) over 3 years in participants with EOAD than in those with LOAD; hence, prediction models for the mean ADAS-Cog trajectories are presented. The younger cohort had a larger proportion of homozygote apolipoprotein E (APOE) ε4 allele carriers than the older cohort; however, APOE genotype was not a significant predictor of cognitive impairment in the multivariate models. A slower rate of cognitive progression was related to initiation of ChEIs at an earlier stage of AD, higher ChEI dose and fewer years of education in both groups. In LOAD, male sex, better instrumental ADL ability and no antipsychotic drug use were additional protective characteristics. The older patients received a lower ChEI dose than the younger individuals during most of the study period.

CONCLUSIONS

Although the participants with EOAD showed a faster decline in ADAS-Cog, had a longer duration of AD before diagnosis, and had a higher frequency of two APOE ε4 alleles than those with LOAD, the cognitive and global responses to ChEI treatment and the longitudinal outcomes after 3 years were similar between the age-at-onset groups. A higher mean dose of ChEI and better cognitive status at the start of therapy were independent protective factors in both groups, stressing the importance of early treatment in adequate doses for all patients with AD.