Economic considerations in the management of Alzheimer's disease

Sparse Graph Representation Learning Based on Reinforcement Learning for Personalized Mild Cognitive Impairment (MCI) Diagnosis

Resting-state functional magnetic resonance imaging (rs-fMRI) has gained attention as a reliable technique for investigating the intrinsic function patterns of the brain. It facilitates the extraction of functional connectivity networks (FCNs) that capture synchronized activity patterns among regions of interest (ROIs). Analyzing FCNs enables the identification of distinctive connectivity patterns associated with mild cognitive impairment (MCI). For MCI diagnosis, various sparse representation techniques have been introduced, including statistical- and deep learning-based methods. However, these methods face limitations due to their reliance on supervised learning schemes, which restrict the exploration necessary for probing novel solutions. To overcome such limitation, prior work has incorporated reinforcement learning (RL) to dynamically select ROIs, but effective exploration remains challenging due to the vast search space during training. To tackle this issue, in this study, we propose an advanced RL-based framework that utilizes a divide-and-conquer approach to decompose the FCN construction task into smaller sub-problems in a subject-specific manner, enabling efficient exploration under each sub-problem condition. Additionally, we leverage the learned value function to determine the sparsity level of FCNs, considering individual characteristics of FCNs. We validate the effectiveness of our proposed framework by demonstrating its superior performance in MCI diagnosis on publicly available cohort datasets.

Multiple Roles of Apolipoprotein E4 in Oxidative Lipid Metabolism and Ferroptosis During the Pathogenesis of Alzheimer's Disease

Alzheimer's disease (AD) is the most prevalent neurodegenerative disease worldwide and has a great socio-economic impact. Modified oxidative lipid metabolism and dysregulated iron homeostasis have been implicated in the pathogenesis of this disorder, but the detailed pathophysiological mechanisms still remain unclear. Apolipoprotein E (APOE) is a lipid-binding protein that occurs in large quantities in human blood plasma, and a polymorphism of the APOE gene locus has been identified as risk factors for AD. The human genome involves three major APOE alleles (APOE2, APOE3, APOE4), which encode for three subtly distinct apolipoprotein E isoforms (APOE2, APOE3, APOE4). The canonic function of these apolipoproteins is lipid transport in blood and brain, but APOE4 allele carriers have a much higher risk for AD. In fact, about 60% of clinically diagnosed AD patients carry at least one APOE4 allele in their genomes. Although the APOE4 protein has been implicated in pathophysiological key processes of AD, such as extracellular beta-amyloid (Aβ) aggregation, mitochondrial dysfunction, neuroinflammation, formation of neurofibrillary tangles, modified oxidative lipid metabolism, and ferroptotic cell death, the underlying molecular mechanisms are still not well understood. As for all mammalian cells, iron plays a crucial role in neuronal functions and dysregulation of iron homeostasis has also been implicated in the pathogenesis of AD. Imbalances in iron homeostasis and impairment of the hydroperoxy lipid-reducing capacity induce cellular dysfunction leading to neuronal ferroptosis. In this review, we summarize the current knowledge on APOE4-related oxidative lipid metabolism and the potential role of ferroptosis in the pathogenesis of AD. Pharmacological interference with these processes might offer innovative strategies for therapeutic interventions.

Resistance Exercise Training as a New Trend in Alzheimer's Disease Research: From Molecular Mechanisms to Prevention

Alzheimer's disease is a pathology characterized by the progressive loss of neuronal connections, which leads to gray matter atrophy in the brain. Alzheimer's disease is the most prevalent type of dementia and has been classified into two types, early onset, which has been associated with genetic factors, and late onset, which has been associated with environmental factors. One of the greatest challenges regarding Alzheimer's disease is the high economic cost involved, which is why the number of studies aimed at prevention and treatment have increased. One possible approach is the use of resistance exercise training, given that it has been shown to have neuroprotective effects associated with Alzheimer's disease, such as increasing cortical and hippocampal volume, improving neuroplasticity, and promoting cognitive function throughout the life cycle. However, how resistance exercise training specifically prevents or ameliorates Alzheimer's disease has not been fully characterized. Therefore, the aim of this review was to identify the molecular basis by which resistance exercise training could prevent or treat Alzheimer's disease.

Differences in the Distribution of Aβ in the Brain between U.S. Veterans and Adults aged 62+ and suffering from Alzheimer's Disease

Background

Elevated concentration of amyloids in the cerebrum results in elevated risks for cerebral hemorrhage and early AD onset following early depression/dementia onset. In this study, we compare patterns of amyloid depositions across eight regions of interest of the human brain between U.S. Veterans and non-Veterans adults aged 62+.

Data

Data were taken from the ADNI and DoD-ADNI studies. A pseudo-randomization algorithm was applied to achieve comparability, reduce bias due to age mismatching, and account for non-treatment-related differences between subsamples extracted from DoD-ADNI and ADNI databases. The pool of participants included data about age, race, apolipoprotein ε4 allele (APOE) status, modified Hachinski Ischemic Score, education level, and geriatric depression score, which were used to build a propensity score.

Predictors and outcomes

Aβ concentration, resulting from the PET image analysis, in key brain regions of interest, and two categorical variables describing the 0.79 and 1.11 cutoffs were used as outcomes, while the Veteran and AD status were used as predictors.

Methods

To balance subsamples, we applied a pseudo-randomization algorithm, eliminating the observed sources of heterogeneity. We used a generalized linear model for continuous variables and the logistic regression model for binary variables.

Findings

The pattern of the Aβ distribution in Veteran's brains was found to be different from the classic AD pattern. The amyloid depositions following Veteran status were concentrated in cerebellar gray matter and the cerebellum in general. In contrast, the AD pattern shows more Aβ depositions in the frontal lobe, cingulate cortex, parietal, and temporal lobes, along with higher whole-cerebrum concentration of amyloids. Since Florbetapir PET cannot distinguish between senile plaques and depositions in blood vessels, the elevated concentration of amyloids in a cerebellum for participants with the Veteran status may suppose elevated risks for cerebral hemorrhage and early AD onset following early depression/dementia onset.

Toward an intelligent computing system for the early diagnosis of Alzheimer's disease based on the modular hybrid growing neural gas

Objective

The proportion of older people will soon include nearly a quarter of the world population. This leads to an increased prevalence of non-communicable diseases such as Alzheimer's disease (AD), a progressive neurodegenerative disorder and the most common dementia. mild cognitive impairment (MCI) can be considered its prodromal stage. The early diagnosis of AD is a huge issue. We face it by solving these classification tasks: MCI-AD and cognitively normal (CN)-MCI-AD.

Methods

An intelligent computing system has been developed and implemented to face both challenges. A non-neural preprocessing module was followed by a processing one based on a hybrid and ontogenetic neural architecture, the modular hybrid growing neural gas (MyGNG). The MyGNG is hierarchically organized, with a growing neural gas (GNG) for clustering followed by a perceptron for labeling. For each task, 495 and 819 patients from the Alzheimer's disease neuroimaging initiative (ADNI) database were used, respectively, each with 211 characteristics.

Results

Encouraging results have been obtained in the MCI-AD classification task, reaching values of area under the curve (AUC) of 0.96 and sensitivity of 0.91, whereas 0.86 and 0.9 in CN-MCI-AD. Furthermore, a comparative study with popular machine learning (ML) models was also performed for each of these tasks.

Conclusions

The MyGNG proved to be a better computational solution than the other ML methods analyzed. Also, it had a similar performance to other deep learning schemes with neuroimaging. Our findings suggest that our proposal may be an interesting computing solution for the early diagnosis of AD.

A comprehensive review of discovery and development of drugs discovered from 2020-2022

To fully evaluate and define the new drug molecule for its pharmacological characteristics and toxicity profile, pre-clinical and clinical studies are conducted as part of the drug research and development process. The average time required for all drug development processes to finish various regulatory evaluations ranges from 11.4 to 13.5 years, and the expense of drug development is rising quickly. The development in the discovery of newer novel treatments is, however, largely due to the growing need for new medications. Methods to identify Hits and discovery of lead compounds along with pre-clinical studies have advanced, and one example is the introduction of computer-aided drug design (CADD), which has greatly shortened the time needed for the drug to go through the drug discovery phases. The pharmaceutical industry will hopefully be able to address the present and future issues and will continue to produce novel molecular entities (NMEs) to satisfy the expanding unmet medical requirements of the patients as the success rate of the drug development processes is increasing. Several heterocyclic moieties have been developed and tested against many targets and proved to be very effective. In-depth discussion of the drug design approaches of newly found drugs from 2020 to 2022, including their pharmacokinetic and pharmacodynamic profiles and in-vitro and in-vivo assessments, is the main goal of this review. Considering the many stages these drugs are going through in their clinical trials, this investigation is especially pertinent. It should be noted that synthetic strategies are not discussed in this review; instead, they will be in a future publication.

Rational Design of Dual Inhibitors for Alzheimer's Disease: Insights from Computational Screening of BACE1 and GSK-3β

BACKGROUND

Alzheimer's disease (AD) is one of the most concerned neurodegenerative disorders across the world characterized by amyloid-beta (Aβ) plaques and neurofibrillary tangles (NFTs), leading to cognitive decline and memory loss. Targeting key pathways involved in AD like Aβ and NFT pathways, are crucial for the development of effective therapeutic strategies. In this study, we aimed to identify and establish promising dual inhibitors targeting BACE1 and GSK-3β, two proteins implicated in Aβ and NFT formation respectively.

METHODS

We have used molecular docking, ADME property analysis, and MMGBSA calculations for the identification of hit molecules and further evaluation of binding affinity, drug-like properties, and stability against BACE1 and GSK-3β.

RESULTS

Our results demonstrated strong binding affinities of ZINC000034853956 towards the active sites of both proteins, with favorable interactions involving key residues crucial for inhibitory activity. Additionally, ZINC000034853956 exhibited favorable drug-like properties. MD simulations revealed the stable binding of ZINC000034853956 to both BACE1 and GSK-3β over a 50 ns period, with consistent ligand-protein interactions, such as hydrogen bonding and hydrophobic contacts. These findings highlight the potential of ZINC000034853956 as a promising candidate for AD treatment, acting as a dual inhibitor targeting both BACE1 and GSK-3β. Overall, our study provides valuable insights into the potential of ZINC000034853956 as a dual inhibitor for AD. The strong binding affinity, favorable drug-like properties, and stability observed in MD simulations support its suitability for further optimization and preclinical studies.

CONCLUSION

Further investigations are warranted to elucidate the precise molecular mechanisms and therapeutic benefits of ZINC000034853956. Our findings offer hope for the development of novel therapeutic interventions targeting crucial pathways involved in AD neurodegeneration.

A Potential Link Between Visceral Obesity and Risk of Alzheimer's Disease

Alzheimer's disease (AD) is the most common type of dementia characterized by the deposition of amyloid beta (Aβ) plaques and tau-neurofibrillary tangles in the brain. Visceral obesity (VO) is usually associated with low-grade inflammation due to higher expression of pro-inflammatory cytokines by adipose tissue. The objective of the present review was to evaluate the potential link between VO and the development of AD. Tissue hypoxia in obesity promotes tissue injury, production of adipocytokines, and release of pro-inflammatory cytokines leading to an oxidative-inflammatory loop with induction of insulin resistance. Importantly, brain insulin signaling is involved in the pathogenesis of AD and lower cognitive function. Obesity and enlargement of visceral adipose tissue are associated with the deposition of Aβ. All of this is consonant with VO increasing the risk of AD through the dysregulation of adipocytokines which affect the development of AD. The activated nuclear factor kappa B (NF-κB) pathway in VO might be a potential link in the development of AD. Likewise, the higher concentration of advanced glycation end-products in VO could be implicated in the pathogenesis of AD. Taken together, different inflammatory signaling pathways are activated in VO that all have a negative impact on the cognitive function and progression of AD except hypoxia-inducible factor 1 which has beneficial and neuroprotective effects in mitigating the progression of AD. In addition, VO-mediated hypoadiponectinemia and leptin resistance may promote the progression of Aβ formation and tau phosphorylation with the development of AD. In conclusion, VO-induced AD is mainly mediated through the induction of oxidative stress, inflammatory changes, leptin resistance, and hypoadiponectinemia that collectively trigger Aβ formation and neuroinflammation. Thus, early recognition of VO by visceral adiposity index with appropriate management could be a preventive measure against the development of AD in patients with VO.

Cannabinoids in neuroinflammatory disorders: Focusing on multiple sclerosis, Parkinsons, and Alzheimers diseases

The medicinal properties of cannabis and cannabinoid-derivative are entirely investigated and known. In addition, the identification of psychotropic plant cannabinoids has led to more studies regarding the cannabinoid system and its therapeutic features in the treatment and management of clinical symptoms of neuroinflammatory disorders, such as multiple sclerosis (MS), Parkinsons disease (PD), and Alzheimers disease (AD). In fact, cannabinoid agonists are able to control and regulate inflammatory responses. In contrast to the cannabinoid receptor type 1 (CB1) and its unwanted adverse effects, the cannabinoid receptor type 2 (CB2) and its ligands hold promise for new and effective therapeutic approaches. So far, some successes have been achieved in this field. This review will discuss an outline of the endocannabinoid system's involvement in neuroinflammatory disorders. Moreover, the pharmacological efficacy of different natural and synthetic preparations of phytocannabinoids acting on cannabinoid receptors, particularly in MS, PD, and AD, will be updated. Also, the reasons for targeting CB2 for neurodegeneration will be explained.

The Case for a Novel Therapeutic Approach to Dementia: Small Molecule Hepatocyte Growth Factor (HGF/MET) Positive Modulators

An estimated 6.5 million Americans aged 65 years or older have Alzheimer's disease (AD), which will grow to 13.8 million Americans by 2060. Despite the growing burden of dementia, no fundamental change in drug development for AD has been seen in > 20 years. Currently approved drugs for AD produce only modest symptomatic improvements in cognition with small effect sizes. A growing mismatch exists between the urgent need to develop effective drugs for symptomatic AD and the largely failed search for disease modification. The failure rate of clinical trials in AD is high overall, and in particular for disease-modifying therapies. Research efforts in AD have focused predominantly on amyloid-β and tau pathologies, but limiting clinical research to these "classical hallmarks" of the disease does not address the most urgent patient, caregiver, or societal needs. Rather, clinical research should consider the complex pathophysiology of AD. Innovative approaches are needed that provide outside-the-box thinking, and re-imagine trial design, interventions, and outcomes as well as progress in proteomics and fluid biomarker analytics for both diagnostics and disease monitoring. A new approach offering a highly specific, yet multi-pronged intervention that exerts positive modulation on the HGF/MET neurotrophic system is currently being tested in mid-to-late-stage clinical trials in mild to moderate AD. Findings from such trials may provide data to support novel approaches for development of innovative drugs for treating AD at various disease stages, including among patients already symptomatic, and may offer benefits for other neurodegenerative diseases.

Statins Use in Alzheimer Disease: Bane or Boon from Frantic Search and Narrative Review

Alzheimer’s disease (AD) was used to describe pre-senile dementia to differentiate it from senile dementia, which develops in the adult age group of more than 65 years. AD is characterized by the deposition of amyloid beta (Aβ) plaque and tau-neurofibrillary tangles (TNTs) in the brain. The neuropathological changes in AD are related to the deposition of amyloid plaques, neurofibrillary tangles, and progression of neuroinflammation, neuronal mitochondrial dysfunction, autophagy dysfunction, and cholinergic synaptic dysfunction. Statins are one of the main cornerstone drugs for the management of cardiovascular disorders regardless of dyslipidemia status. Increasing the use of statins, mainly in the elderly groups for primary and secondary prevention of cardiovascular diseases, may affect their cognitive functions. Extensive and prolonged use of statins may affect cognitive functions in healthy subjects and dementia patients. Statins-induced cognitive impairments in both patients and health providers had been reported according to the post-marketing survey. This survey depends mainly on sporadic cases, and no cognitive measures were used. Evidence from prospective and observational studies gives no robust conclusion regarding the beneficial or detrimental effects of statins on cognitive functions in AD patients. Therefore, this study is a narrative review aimed with evidences to the beneficial, detrimental, and neutral effects of statins on AD.

A Novel Role for BRIP1/FANCJ in Neuronal Cells Health and in Resolving Oxidative Stress-Induced DNA Lesions

BACKGROUND

DNA damage accumulation and mitochondrial abnormalities are elevated in neurons during aging and may contribute to neurodegenerative pathologic conditions such as Alzheimer's disease. BRCA1 interacting protein 1 or BRIP1 is a 5' to 3' DNA helicase that catalyzes many abnormal DNA structures during DNA replication, gene transcription, and recombination, and contribute to genomic integrity.

OBJECTIVE

BRIP1 functions were reasonably well studied in DNA repair; however, there is limited data on its role and regulation during aging and neurodegenerative diseases.

METHODS

We used immunohistochemistry, western blot, and qRT-PCR assays to analyze the expression of BRIP1. Immunofluorescence studies were performed to study the formation of R-loops, reactive oxygen species (ROS) generation, and mitochondrial morphology. Flow cytometry and transmission electron microscopy were used to evaluate mitochondrial ROS and mitochondrial structures, respectively. Oxygen consumption rate was measured using Seahorse, and the Presto Blue™ assays were used to evaluate cell viability.

RESULTS

Our results demonstrate the expression of BRIP1 in mouse and human brain tissues and in neuronal cell lines. BRIP1 levels were elevated in the hippocampal regions of the brains, specifically in the dentate gyrus. BRIP1 downregulation in neuronal cells caused increased R-loop formation basally and in response to H2O2 treatment. Furthermore, BRIP1 deficient cells exhibited elevated levels of excitotoxicity induced by L-Glutamic acid exposure as evidenced by (mitochondrial) ROS levels, deteriorated mitochondrial health, and cell death compared to BRIP1 proficient neuronal cells.

CONCLUSION

Overall, our results indicate an important role for BRIP1 in maintaining neuronal cell health and homeostasis by suppressing cellular oxidative stress.

Natural Products for Neurodegeneration: Regulating Neurotrophic Signals

Neurodegenerative disorders (NDs) are heterogeneous groups of ailments typically characterized by progressive damage of the nervous system. Several drugs are used to treat NDs but they have only symptomatic benefits with various side effects. Numerous researches have been performed to prove the advantages of phytochemicals for the treatment of NDs. Furthermore, phytochemicals such as polyphenols might play a pivotal role in rescue from neurodegeneration due to their various effects as anti-inflammatory, antioxidative, and antiamyloidogenic agents by controlling apoptotic factors, neurotrophic factors (NTFs), free radical scavenging system, and mitochondrial stress. On the other hand, neurotrophins (NTs) including nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), NT4/5, and NT3 might have a crucial neuroprotective role, and their diminution triggers the development of the NDs. Polyphenols can interfere directly with intracellular signaling molecules to alter brain activity. Several natural products also improve the biosynthesis of endogenous genes encoding antiapoptotic Bcl-2 as well as NTFs such as glial cell and brain-derived NTFs. Various epidemiological studies have demonstrated that the initiation of these genes could play an essential role in the neuroprotective function of dietary compounds. Hence, targeting NTs might represent a promising approach for the management of NDs. In this review, we focus on the natural product-mediated neurotrophic signal-modulating cascades, which are involved in the neuroprotective effects.

Smart home technology solution for night-time wandering in persons with dementia

Introduction

More than half of persons with dementia will experience night-time wandering, increasing their risk of falls and unattended home exits. This is a major predictor of caregiver burnout and one of the major causes of early institutionalization.

Methods

Using smart home technologies such as sensors, smart bulbs, pressure mats and speakers, the Night-time Wandering Detection and Diversion system is designed to assist caregivers and persons with dementia that are at risk of wandering at night. Being placed in homes around Ottawa for a 12-week trial, the system allows caregivers to rest peacefully in the night, as it detects when the person with dementia gets out of bed and automatically provides cue lighting to guide them safely to the washroom. The system also uses prerecorded audio prompts, if they venture from the bedroom, only waking the caregiver when the person with dementia opens an exit door.

Results

Thus far, the average depression and anxiety in caregivers have been improved after the 12 weeks, and most have said that they sleep more peacefully.

Conclusion

The system has proven successful in supporting the safety of persons with dementia as well as their caregivers.

Herbal medicine treatment for Alzheimer disease: A protocol for a systematic review and meta-analysis

BACKGROUND

Alzheimer disease (AD) is a leading progressive neurodegenerative disease worldwide, but treating it is challenging in clinical practice. This review is aimed at evaluating the efficacy and safety of herbal medicine for treating AD.

METHODS AND ANALYSIS

We will search for randomized controlled trials related to the effect and safety of herbal medicine for AD in the following databases: PubMed, Cochrane Central Register of Controlled Trials, Excerpta Medica Database, China National Knowledge Infrastructure database, Oriental Medicine Advanced Searching Integrated system, Korean Traditional Knowledge Portal, and Citation Information by National Institute for Informatics. The risk of bias will be evaluated using the Cochrane risk-of-bias assessment tool. After screening the studies, a meta-analysis will be performed. The primary outcome will be the Mini-Mental State Examination score. Secondary outcomes will consist of other scales for cognitive function and other aspects, such as behavioral and psychological symptoms and plasma levels of amyloid-β.

RESULTS

This study will provide the current status of evidence for herbal medicine to treat AD.

CONCLUSION

The results of this review will determine the efficacy and safety of herbal medicine for AD.

ETHICS AND DISSEMINATION

Ethical approval is not required, as this study is based on a review of published research. This review will be published in a peer-reviewed journal and disseminated both electronically and in print.

TRIAL REGISTRATION NUMBER

Research Registry reviewregistry933.

"Choosing Wisely": Apolipoprotein E Genetic Testing for the Diagnosis of Alzheimer's Disease in Dementia Clinics

BACKGROUND

Apolipoprotein E (APOE) ɛ4 allele carriers have an increased risk of late-onset Alzheimer's disease (AD). However, in the "Choosing Wisely" campaign for avoiding unnecessary medical tests, treatments, and procedures, APOE genetic testing is not recommended as a predictive test for AD.

OBJECTIVE

The aim of this study was to investigate the potential value of APOE genetic testing in a specific clinical context.

METHODS

Subjects with poor performance in the Korean version of the Mini-Mental Status Examination for dementia screening (MMSE-DS) with a Z-score of less than -1.5 were recruited from the public health centers. All participants underwent APOE genetic testing. Family history of dementia (FHx) was confirmed if one or more first-degree relatives had dementia.

RESULTS

Among 349 subjects, 162 (46.4%) were diagnosed with AD. APOEɛ4 allele carriers had a much higher risk of AD in the group with FHx than in the group without FHx (OR = 15.81, 95% CI = 2.74-91.21 versus OR = 1.82, 95% CI = 1.00-3.27, z = 2.293, p = 0.011). The sensitivity, specificity, positive predictive value, and negative predictive value for the APOEɛ4 allele were 47.7%, 90.9%, 91.3%, and 46.5% in the group with FHx.

CONCLUSION

It would be a wise choice to perform the APOE genetic testing for the diagnosis of AD in subjects with poor performance in a screening test and a family history of dementia.

Alzheimer's Diagnosis: Real-World Physician Behavior Across Countries

INTRODUCTION

Appropriate management of patients with Alzheimer's disease (AD) helps preserve their independence and time at home. We explored physician behavior in the management of AD, focusing on diagnosis.

METHODS

Online questionnaires and patient record forms (PRFs) were created by an independent market research agency and completed by participating physicians. Physicians were recruited from France, Germany, Japan, the UK, and the USA. A sample of 1086 physicians was recruited, including general practitioners, geriatricians, neurologists, and psychiatrists. Physicians completed an online interview and 2-3 PRFs based on randomly selected records of their patients with AD. Data on triggers and timing of diagnosis were captured. Data were assessed for all countries combined (global) and within each country and physician specialty.

RESULTS

A total of 3346 PRFs were submitted. Approximately half of patients received diagnosis within 6 months. There were large country differences. In France, only 35% of patients were diagnosed within 6 months compared to 65% in Japan. Physicians in France also reported diagnoses taking > 9 months for a substantial number of patients (39%) compared with other countries (16-29%). Caregivers were the main driver toward diagnosis. Physician suspicion of AD was a trigger for diagnosis in only 20% of cases, globally. Overall, referral rates were low (14-23%).

CONCLUSION

This study suggests that detection and timely diagnosis of AD remains suboptimal. This highlights the importance of fostering awareness of early symptoms and education on the benefits of timely diagnosis, a critical step in initiating treatment as early as possible.

Bin1 antibody lowers the expression of phosphorylated Tau in Alzheimer's disease

Alzheimer's disease (AD) is an irreversible, progressive brain disorder responsible for memory loss leading to the inability to carry out the simplest tasks. AD is one of the leading causes of death in the United States. As yet there are no effective medications to treat this debilitating disease. In recent years, a human gene called bridging integrator 1 (BIN1) has emerged as one of the most important genes in affecting the incidence of sporadic AD. Bin1 can directly bind to Tau and mediates late onset AD risk by modulating Tau pathology. Recently our group found Bin1 antibody could exert drug-like properties in an animal model of ulcerative colitis. We hypothesized that the Bin1 monoclonal antibody (mAb) could be used in the treatment of AD by lowering the levels of Tau in cell culture and animal models. Cell culture studies confirmed that the Bin1 mAb (99D) could lower the levels of phosphorylated Tau (pTau). Multiple mechanisms aided by endosomal proteins and Fc gamma receptors are involved in the uptake of Bin1 mAb into cells. In Tau expressing cell culture, the Bin1 mAb induces the proteasome machinery leading to ubiquitination of molecules thereby preventing cell stress. In vivo studies demonstrated that treatment of P301S mice expressing Tau with the Bin1 mAb survived longer than the untreated mice. Our data confirm that Bin1 mAb lowers the levels of pTau and could be a drug candidate in the treatment of AD.

Traditional Oriental Medicines and Alzheimer's Disease

Alzheimer’s disease (AD), which is the most major cause of dementia, is a progressive neurodegenerative disease that affects cognitive functions. Even though the prevalence of AD is continuously increasing, few drugs including cholinesterase inhibitors and N-methyl D-aspartate-receptor antagonists were approved to treat AD. Because the clinical trials of AD drugs with single targets, such as β-amyloid and tau, have failed, the development of multi-target drugs that ameliorate many of the symptoms of AD is needed. Thus, recent studies have investigated the effects and underlying mechanisms of herbal formulae consisting of various herb combinations used to treat AD. This review discusses the results of clinical and nonclinical studies of the therapeutic efficacy in AD and underlying mechanisms of the herbal formulae of traditional Oriental medicines and bioactive compounds of medicinal plants.

Astroglia in Alzheimer's Disease

Alzheimer's disease is the most common cause of dementia. Cellular changes in the brains of the patients suffering from Alzheimer's disease occur well in advance of the clinical symptoms. At the cellular level, the most dramatic is a demise of neurones. As astroglial cells carry out homeostatic functions of the brain, it is certain that these cells are at least in part a cause of Alzheimer's disease. Historically, Alois Alzheimer himself has recognised this at the dawn of the disease description. However, the role of astroglia in this disease has been understudied. In this chapter, we summarise the various aspects of glial contribution to this disease and outline the potential of using these cells in prevention (exercise and environmental enrichment) and intervention of this devastating disease.

Investigation of possible risk factors for depression in Alzheimer's disease: A systematic review of the evidence

BACKGROUND

Depression is common in people with Alzheimer's disease (AD), and is associated with increased risk of institutionalization and mortality. Understanding risk factors for depression in AD is key to its development and treatment.

METHODS

We searched the MEDLINE, EMBASE, PsycINFO, and CINAL databases for longitudinal prospective cohort studies that evaluated risk factors for depression in people with AD. Two authors independently selected articles for inclusion and assessed quality of studies using predetermined criteria.

RESULTS

In seven studies that met the inclusion criteria, 2029 participants were followed up for a median of 5 years. Gender and educational attainment were not predictors of depression risk. History of a past psychiatric disorder and greater cognitive impairment predicted increased risk of depression in more than one study. In single studies, younger age, having a family history of psychiatric disorder, neuroticism, functional decline, presence of sleep disturbance and aggression, and increased cardiovascular risk predicted depression risk. Not being within 6 months of dementia onset and, counterintuitively having two comorbid disorders were protective factors in one study.

LIMITATIONS

A small number of studies exist overall and only a few have examined the same risk factors. Most of the studies have measured depression using scales that are not validated in AD.

CONCLUSIONS

These results inform a preliminary model of depression risk in people with AD. Unlike in the general population, men and women and those with higher and lower educational levels of attainment may be equally at risk of depression. Clinicians should be aware of these possible differences in the risk profile for depression in AD populations, to assist detection and enable early treatment. Interventions to delay cognitive and functional decline may reduce depression risk.

Effects of 2-Year Cognitive⁻Motor Dual-Task Training on Cognitive Function and Motor Ability in Healthy Elderly People: A Pilot Study

We aimed to examine the effect of 2-year cognitive⁻motor dual-task (DT) training on cognitive functions and motor ability of healthy elderly people without marked cognitive impairment. From the 25 participants of our 12-week DT trial conducted in 2014, we recruited 8 subjects who voluntarily participated in a new DT training program once a week for 2 years (exercise (EX) group). Their cognitive functions were evaluated by the Modified Mini-Mental State (3MS) examination and the Trail Making Test, and results were compared with those of the 11 subjects who discontinued the training and did not perform any types of exercise for 2 years (non-exercise (NO) group). Subjects in the NO group showed deterioration in the 3MS examination results, especially in the cognitive domain of attention. Meanwhile, participation in DT training maintained the scores in almost all domains of cognitive function, as well as the total 3MS scores. However, both groups had impaired quadriceps muscle strength and motor ability after the 2-year observation period. These results suggest that participating in exercise program comprising DT training for 2 years may be beneficial for maintaining the broad domains of cognitive function in healthy elderly people, although further verification is needed.

Risk Factors for Institutionalization After Traumatic Brain Injury Inpatient Rehabilitation

OBJECTIVE

To create a profile of individuals with traumatic brain injury (TBI) who received inpatient rehabilitation and were discharged to an institutional setting using characteristics measured at rehabilitation discharge.

METHODS

The Traumatic Brain Injury Model Systems National Database is a prospective, multicenter, longitudinal database for people with moderate to severe TBI. We analyzed data for participants enrolled from January 2002 to June 2012 who had lived in a private residence before TBI. This cross-sectional study used logistic regression analyses to identify sociodemographic factors, lengths of stay, and cognitive and physical functioning levels that differentiated patients discharged to institutional versus private settings.

RESULTS

Older age, living alone before TBI, and lower levels of function at rehabilitation discharge (independence in locomotion, bladder management, comprehension, and social interaction) were significantly associated with higher institutionalization rates and provided the best models identifying factors associated with institutionalization. Institutionalization was also associated with decreased independence in bed-chair-wheelchair transfers and increased duration of posttraumatic amnesia.

CONCLUSIONS

Individuals institutionalized after inpatient rehabilitation for TBI were older, lived alone before injury, had longer posttraumatic amnesia durations, and were less independent in specific functional characteristics. Research evaluating the effect of increasing postdischarge support and improving treatment effectiveness in these functional areas is recommended.

Alzheimer Disease and Related Disorders and Out-of-Pocket Health Care Spending and Burden Among Elderly Medicare Beneficiaries

OBJECTIVE

To estimate the excess burden of out-of-pocket health care spending associated with Alzheimer disease and related disorders (ADRD) among older individuals (age 65 y and older).

METHODS

We adopted a retrospective, cross-sectional study design with data from 2012 Medicare Current Beneficiary Survey. The study sample comprised of elderly community-dwelling individuals who had positive total health care expenditures, and enrolled in Medicare throughout the calendar year (462 with ADRD, and 7160 without ADRD). We estimated the per-capita total annual out-of-pocket spending on health care and out-of-pocket spending by service type: inpatient, outpatient, home health, prescription drugs, and other services. We measured out-of-pocket spending burden by calculating the percentage of income spent on health care and defined high out-of-pocket spending burden as having this percentage above 10%. Multivariable analyses included ordinary least squares regressions and logistic regressions and these analyses adjusted for predisposing, enabling, need, personal health care practices and external environment characteristics.

RESULTS

The average annual per-capita out-of-pocket health care spending was greater among individuals with ADRD compared with those without ADRD ($3285 vs. $1895); home health and prescription drugs accounted for 52% of total out-of-pocket spending among individuals with ADRD and 34% among individuals without ADRD. Elderly individuals with ADRD were more likely to have high out-of-pocket spending burden (adjusted odds ratio, 1.49; 95% confidence interval, 1.13-1.97) compared with those without ADRD.

CONCLUSION

ADRD is associated with excess out-of-pocket health care spending, primarily driven by prescription drugs and home health care use.

Report by the Spanish Foundation of the Brain on the social impact of Alzheimer disease and other types of dementia

INTRODUCTION

Knowledge of the socioeconomic impact of dementia-related disorders is essential for appropriate management of healthcare resources and for raising social awareness.

METHODS

We performed a literature review of the published evidence on the epidemiology, morbidity, mortality, associated disability and dependence, and economic impact of dementia and Alzheimer disease (AD) in Spain.

CONCLUSIONS

Most population studies of patients older than 65 report prevalence rates ranging from 4% to 9%. Prevalence of dementia and AD is higher in women for nearly every age group. AD is the most common cause of dementia (50%-70% of all cases). Dementia is associated with increased morbidity, mortality, disability, and dependence, and results in a considerable decrease in quality of life and survival. Around 80% of all patients with dementia are cared for by their families, which cover a mean of 87% of the total economic cost, resulting in considerable economic and health burden on caregivers and loss of quality of life. The economic impact of dementia is huge and difficult to evaluate due to the combination of direct and indirect costs. More comprehensive programmes should be developed and resources dedicated to research, prevention, early diagnosis, multidimensional treatment, and multidisciplinary management of these patients in order to reduce the health, social, and economic burden of dementia.

Cassia tora Linn.: A boon to Alzheimer's disease for its anti-amyloidogenic and cholinergic activities

BACKGROUND

Drug discovery from natural products as alternatives for Alzheimer's disease (AD) is a current trend. For which plant is an alternative for searching potential molecule for treating AD. Availability of Cassia tora as weed and abundance in nature makes it as potential source. Many plants group under Leguminosae family has potential medicinal property of which Cassia tora is an appropriate choice, to know potency against AD. Etiology of AD is described by senile plaques and neurofibrillary tangles. The Aβ₄₂ has key major role in forming plaques by forming structures like protobirils, oligomers and final fibrilar like structures. Even at in vitro conditions, the peptides have a fibrilar like structure, which was exploited to preliminary screening of natural sources that may be effective in treating AD.

HYPOTHESIS/PURPOSE

The design of the study was to unravel the potential medicinal property of Cassia tora for its antioxidant, cholinergic and aggregation inhibition activity.

STUDY DESIGN

We evidenced that the methanol (MeOH), n-hexane (n-hex), petroleum ether (PE) and aqueous (aq) extracts from the leaves of Cassia tora (C. tora) were investigated for their inhibitory activity against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and anti-amyloidogenic assays. The antioxidant effect using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, total phenolic and flavonoid contents of the extracts were determined using Folin-Ciocaltaeu's and aluminum chloride (AlCl₃) reagents, respectively.

RESULTS

The methanol extract of C. tora exerted the highest inhibition against AChE (55.38 ± 2.28%) and BChE inhibition (50.02 ± 0.79%) at 100µg/ml concentration. The methanol extract was also found more active in the antioxidant test. The aggregation kinetics was monitored using thioflavin-T (ThT) assay and transmission electron microscopy (TEM) technique.

CONCLUSION

The results showed that C. tora methanol extract is able to inhibit the Aβ₄₂ aggregation from monomers and oligomers and also able to dis-aggregate the pre-formed fibrils. The study provides an insight on finding new natural products for AD therapeutics.

Informal Care Time and Cost in a Large Clinical Trial Sample of Patients with Mild to Moderate Alzheimer's Disease: Determinants and Level of Change Observed

INTRODUCTION

We evaluate the association between caregiver (informal) time/cost and illness severity from two recently completed clinical trials of an investigational drug for Alzheimer's disease (AD).

METHODS

Changes from baseline caregiver time were calculated and treatment effects analyzed using a restricted maximum likelihood-based mixed model for repeated measures. Four separate models were then estimated to examine the association between caregiver time costs and the clinical endpoints measured during the trials, including cognition (MMSE), function (DAD), behavior (NPI), global disability (CDR) and dependence (DS).

RESULTS

Caregiver time cost was significantly associated with all clinical measures of illness severity with a 1-unit change in MMSE, DAD, NPI, CDR and DS associated with a 11.57%, 4.81-4.97%, 3.58-3.67%, 42.52% and 71.05% change, respectively, in primary caregiver time cost. The association between caregiver time cost and DS was the strongest of all the associations examined.

CONCLUSION

Caregiver time costs increase with increasing AD severity in all key domains of AD (cognition, function, behavior, global disability and dependence on others). Our analysis demonstrated that patient dependence is a particularly important predictor of caregiver time costs and should be considered as a potential outcome measure in intervention clinical trials in AD.

FUNDING

Pfizer Inc. and Janssen Alzheimer Immunotherapy Research and Development.

Spatial recognition test: A novel cognition task for assessing topographical memory in mice

Dysfunction in topographical memory is a core feature of several neurological disorders. There is a large unmet medical need to address learning and memory deficits as a whole in central nervous system disease. There are considerable efforts to identify pro-cognitive compounds but current methods are either lengthy or labour intensive. Our test used a two chamber apparatus and is based on the preference of rodents to explore novel environments. It was used firstly to assess topographical memory in mice at different retention intervals (RI) and secondly to investigate the effect of three drugs reported to be beneficial for cognitive decline associated with Alzheimer's disease, namely: donepezil, memantine and levetiracetam. Animals show good memory performance at all RIs tested under four hours. At the four-hour RI, animals show a significantly poorer memory performance which can be rescued using donepezil, memantine and levetiracetam. Using this test we established and validated a spatial recognition paradigm to address topographical memory in mice by showing a decremental time-induced forgetting response and reversing this decrease in performance using pharmacological tools. The spatial recognition test differs from more commonly used visuospatial laboratory tests in both throughput capability and potentially neuroanatomical substrate. This test has the potential to be used to assess cognitive performance in transgenic animals, disease models and to screen putative cognitive enhancers or depressors.

Trends, Predictors, and Outcomes of Healthcare Resources Used in Patients Hospitalized with Alzheimer's Disease with at Least One Procedure: The Nationwide Inpatient Sample

We assessed trends, predictors and outcomes of resource utilization in hospital inpatient discharges with a principal diagnosis of Alzheimer's disease (AD) with at least one procedure. Using Nationwide Inpatient Sample data (NIS, 2002-2012), discharges primarily diagnosed with AD, aged ≥60 y and with ≥1 procedure, were selected (Weighted N = 92,300). Hospital resource utilization were assessed using ICD-9-CM codes, while hospitalization outcomes included total charges (TC, 2012$), length of stay (LOS, days), and mortality risk (MR, %). Brain and respiratory/gastrointestinal procedure utilization both dropped annually by 3-7%, while cardiovascular procedures/evaluations, blood evaluations, blood transfusion, and resuscitation ("CVD/Blood") as well as neurophysiological and psychological evaluation and treatment ("Neuro") procedures increased by 5-8%. Total charges, length of stay, and mortality risk were all markedly higher with use of respiratory/gastrointestinal procedures as opposed to being reduced with use of "Brain" procedures. Procedure count was positively associated with all three hospitalization outcomes. In sum, patterns of hospital resources that were used among AD inpatients changed over-time, and were associated with hospitalization outcomes such as total charges, length of stay, and mortality risk.

Copper Ion Binding Site in β-Amyloid Peptide

β-Amyloid aggregates in the brain play critical roles in Alzheimer's disease, a chronic neurodegenerative condition. Amyloid-associated metal ions, particularly zinc and copper ions, have been implicated in disease pathogenesis. Despite the importance of such ions, the binding sites on the β-amyloid peptide remain poorly understood. In this study, we use scanning tunneling microscopy, circular dichroism, and surface-enhanced Raman spectroscopy to probe the interactions between Cu²⁺ ions and a key β-amyloid peptide fragment, consisting of the first 16 amino acids, and define the copper-peptide binding site. We observe that in the presence of Cu²⁺, this peptide fragment forms β-sheets, not seen without the metal ion. By imaging with scanning tunneling microscopy, we are able to identify the binding site, which involves two histidine residues, His13 and His14. We conclude that the binding of copper to these residues creates an interstrand histidine brace, which enables the formation of β-sheets.

Ultrasound treatment of neurological diseases--current and emerging applications

Like cardiovascular disease and cancer, neurological disorders present an increasing challenge for an ageing population. Whereas nonpharmacological procedures are routine for eliminating cancer tissue or opening a blocked artery, the focus in neurological disease remains on pharmacological interventions. Setbacks in clinical trials and the obstacle of access to the brain for drug delivery and surgery have highlighted the potential for therapeutic use of ultrasound in neurological diseases, and the technology has proved useful for inducing focused lesions, clearing protein aggregates, facilitating drug uptake, and modulating neuronal function. In this Review, we discuss milestones in the development of therapeutic ultrasound, from the first steps in the 1950s to recent improvements in technology. We provide an overview of the principles of diagnostic and therapeutic ultrasound, for surgery and transient opening of the blood-brain barrier, and its application in clinical trials of stroke, Parkinson disease and chronic pain. We discuss the promising outcomes of safety and feasibility studies in preclinical models, including rodents, pigs and macaques, and efficacy studies in models of Alzheimer disease. We also consider the challenges faced on the road to clinical translation.

Errors in self-reports of health services use: impact on alzheimer disease clinical trial designs

BACKGROUND

Most Alzheimer disease clinical trials that compare the use of health services rely on reports of caregivers. The goal of this study was to assess the accuracy of self-reports among older adults with Alzheimer disease and their caregiver proxy respondents. This issue is particularly relevant to Alzheimer disease clinical trials because inaccuracy can lead both to loss of power and increased bias in study outcomes.

METHODS

We compared respondent accuracy in reporting any use and in reporting the frequency of use with actual utilization data as documented in a comprehensive database. We next simulated the impact of underreporting and overreporting on sample size estimates and treatment effect bias for clinical trials comparing utilization between experimental groups.

RESULTS

Respondents self-reports have a poor level of accuracy with κ-values often below 0.5. Respondents tend to underreport use even for rare events such as hospitalizations and nursing home stays. In analyses simulating underreporting and overreporting of varying magnitude, we found that errors in self-reports can increase the required sample size by 15% to 30%. In addition, bias in the reported treatment effect ranged from 3% to 18% due to both underreporting and overreporting errors.

CONCLUSIONS

Use of self-report data in clinical trials of Alzheimer disease treatments may inflate sample size needs. Even when adequate power is achieved by increasing sample size, reporting errors can result in a biased estimate of the true effect size of the intervention.

Dementia severity and the longitudinal costs of informal care in the Cache County population

BACKGROUND

Dementia costs are critical for influencing healthcare policy, but limited longitudinal information exists. We examined longitudinal informal care costs of dementia in a population-based sample.

METHODS

Data from the Cache County Study included dementia onset, duration, and severity assessed by the Mini-Mental State Examination (MMSE), Clinical Dementia Rating Scale (CDR), and Neuropsychiatric Inventory (NPI). Informal costs of daily care (COC) was estimated based on median Utah wages. Mixed models estimated the relationship between severity and longitudinal COC in separate models for MMSE and CDR.

RESULTS

Two hundred and eighty-seven subjects (53% female, mean (standard deviation) age was 82.3 (5.9) years) participated. Overall COC increased by 18% per year. COC was 6% lower per MMSE-point increase and compared with very mild dementia, COC increased over twofold for mild, fivefold for moderate, and sixfold for severe dementia on the CDR.

CONCLUSIONS

Greater dementia severity predicted higher costs. Disease management strategies addressing dementia progression may curb costs.

Direct costs of dementia in nursing homes

Dementia represents an economical burden to societies nowadays. Total dementia expenses are calculated by the sum of direct and indirect costs. Through the stages of the diseases, as the patients may require institutionalization or a formal caregiver, the direct costs tend to increase. This study aims to analyze the direct costs of dementia in Portuguese nursing homes in 2012, compare the spending between seniors with and without dementia, and propose a predictive costs model. The expenses analysis was based on (1) the use of emergency rooms and doctor's appointments, either in public or private institutions; (2) days of hospitalization; (3) medication; (4) social services use; (5) the need for technical support; and (6) the utilization of rehabilitation services. The sample was composed of 72 people, half with dementia and half without. The average annual expense of a patient with dementia was €15,287 thousand, while the cost of a patient without dementia was about €12,289 thousand. The variables "ability to make yourself understood," "self-performance: getting dressed" and "thyroid disorders" were found to be statistically significant in predicting the expenses' increase. In nursing homes, in 2012, the costs per patient with dementia were 1, 2 times higher than per patient without dementia.

Mitochondria-Targeted Protective Compounds in Parkinson's and Alzheimer's Diseases

Mitochondria are cytoplasmic organelles that regulate both metabolic and apoptotic signaling pathways; their most highlighted functions include cellular energy generation in the form of adenosine triphosphate (ATP), regulation of cellular calcium homeostasis, balance between ROS production and detoxification, mediation of apoptosis cell death, and synthesis and metabolism of various key molecules. Consistent evidence suggests that mitochondrial failure is associated with early events in the pathogenesis of ageing-related neurodegenerative disorders including Parkinson's disease and Alzheimer's disease. Mitochondria-targeted protective compounds that prevent or minimize mitochondrial dysfunction constitute potential therapeutic strategies in the prevention and treatment of these central nervous system diseases. This paper provides an overview of the involvement of mitochondrial dysfunction in Parkinson's and Alzheimer's diseases, with particular attention to in vitro and in vivo studies on promising endogenous and exogenous mitochondria-targeted protective compounds.

CANTAB object recognition and language tests to detect aging cognitive decline: an exploratory comparative study

Objective

The recognition of the limits between normal and pathological aging is essential to start preventive actions. The aim of this paper is to compare the Cambridge Neuropsychological Test Automated Battery (CANTAB) and language tests to distinguish subtle differences in cognitive performances in two different age groups, namely young adults and elderly cognitively normal subjects.

Method

We selected 29 young adults (29.9±1.06 years) and 31 older adults (74.1±1.15 years) matched by educational level (years of schooling). All subjects underwent a general assessment and a battery of neuropsychological tests, including the Mini Mental State Examination, visuospatial learning, and memory tasks from CANTAB and language tests. Cluster and discriminant analysis were applied to all neuropsychological test results to distinguish possible subgroups inside each age group.

Results

Significant differences in the performance of aged and young adults were detected in both language and visuospatial memory tests. Intragroup cluster and discriminant analysis revealed that CANTAB, as compared to language tests, was able to detect subtle but significant differences between the subjects.

Conclusion

Based on these findings, we concluded that, as compared to language tests, large-scale application of automated visuospatial tests to assess learning and memory might increase our ability to discern the limits between normal and pathological aging.

Impact of physical exercise on quality of life of older adults with depression or Alzheimer's disease: a systematic review

INTRODUCTION: Physical exercise has been associated with improvement of quality of live (QoL), but its effect among the elderly with depression and Alzheimer's disease (AD) is still unclear. This systematic review evaluated randomized and controlled studies about the effect of physical exercise on QoL of older individuals with a clinical diagnosis of depression and AD.METHODS:We searched PubMed, ISI, SciELO and Scopus from December 2011 to June 2013 using the following keywords: physical exercise, quality of life, elderly, depression, Alzheimer's disease. Only six studies met inclusion criteria: two examined patients with AD and four, patients with depression.RESULTS: The studies used different methods to prescribe exercise and evaluate QoL, but all had high quality methods. Findings of most studies with individuals with depression suggested that exercise training improved QoL, but studies with patients with AD had divergent results.CONCLUSIONS: Although different methods were used, results suggested that physical exercise is an effective non-pharmacological intervention to improve the QoL of elderly individuals with depression and AD. Future studies should investigate the effect of other factors, such as the use of specific scales for the elderly, controlled exercise prescriptions and type of control groups.

Efficacy of memantine, donepezil, or their association in moderate-severe Alzheimer's disease: a review of clinical trials

Background. Acetylcholinesterase (AChE)/cholinesterase (ChE) inhibitors (Is) and memantine are licensed for symptomatic treatment of mild-moderate and moderate-severe forms of Alzheimer's disease (AD), respectively. High doses of the AChE-I donepezil were licensed in the USA for moderate-severe AD, and the association AChE/ChE-Is plus memantine was proposed for AD at this stage. Objectives. This paper has reviewed evidence from clinical trials of the effectiveness of memantine, donepezil, or the two drugs in association in managing moderate-severe AD. Method. Double-blind, placebo-controlled randomized trials (RCTs) using memantine or donepezil alone or in association versus placebo in moderate-severe AD were reviewed. Analysis done in January 2013 considered the years 2007–2012. Results and Conclusion. Only 83 of the 941 papers selected were considered relevant, and only 13 met the criterion of “adequacy and representativeness.” Memantine and donepezil lead to improvements in moderate-to-severe AD and the choice between the compounds should be based on their contraindications more than on disease severity. No evidence was found of advantages of the association of memantine-donepezil. The heterogeneity of conditions explored by RCTs, the relatively short time of observation (24–52 weeks), and the different cognitive assessment tools used did not allow comparing properly different trials.

Economic analysis of the intangible impacts of informal care for people with Alzheimer's disease and other mental disorders

OBJECTIVES

Valuation of the intangible impacts of informal care remains a great challenge for economic evaluation, especially in the framework of care recipients with cognitive impairment. Our main objective was to explore the influence of intangible impacts of caring on both informal caregivers' ability to estimate their willingness to pay (WTP) to be replaced and their WTP value.

METHODS

We mapped characteristics that influence ability or inability to estimate WTP by using a multiple correspondence analysis. We ran a bivariate probit model with sample selection to further analyze the caregivers' WTP value conditional on their ability to estimate their WTP.

RESULTS

A distinction exists between the opportunity costs of the caring dimension and those of the intangible costs and benefits of caring. Informal caregivers' ability to estimate WTP is negatively influenced by both intangible benefits from caring (P < 0.001) and negative intangible impacts of caring (P < 0.05). Caregivers' WTP value is negatively associated with positive intangible impacts of informal care (P < 0.01).

CONCLUSIONS

Informal caregivers' WTP and their ability to estimate WTP are both influenced by intangible burden and benefit of caring. These results call into question the relevance of a hypothetical generalized financial compensation system as the optimal way to motivate caregivers to continue providing care.