The economics of Alzheimer disease

Convolutional Neural Networks to Classify Alzheimer’s Disease Severity Based on SPECT Images: A Comparative Study

Image recognition and neuroimaging are increasingly being used to understand the progression of Alzheimer’s disease (AD). However, image data from single-photon emission computed tomography (SPECT) are limited. Medical image analysis requires large, labeled training datasets. Therefore, studies have focused on overcoming this problem. In this study, the detection performance of five convolutional neural network (CNN) models (MobileNet V2 and NASNetMobile (lightweight models); VGG16, Inception V3, and ResNet (heavier weight models)) on medical images was compared to establish a classification model for epidemiological research. Brain scan image data were collected from 99 subjects, and 4711 images were used. Demographic data were compared using the chi-squared test and one-way analysis of variance with Bonferroni’s post hoc test. Accuracy and loss functions were used to evaluate the performance of CNN models. The cognitive abilities screening instrument and mini mental state exam scores of subjects with a clinical dementia rating (CDR) of 2 were considerably lower than those of subjects with a CDR of 1 or 0.5. This study analyzed the classification performance of various CNN models for medical images and proved the effectiveness of transfer learning in identifying the mild cognitive impairment, mild AD, and moderate AD scoring based on SPECT images.

The economic burden of dementia in low- and middle-income countries (LMICs): a systematic review

Introduction

More than two-thirds of people with dementia live in low- and middle-income countries (LMICs), resulting in a significant economic burden in these settings. In this systematic review, we consolidate the existing evidence on the cost of dementia in LMICs.

Methods

Six databases were searched for original research reporting on the costs associated with all-cause dementia or its subtypes in LMICs. The national-level dementia costs inflated to 2019 were expressed as percentages of each country’s gross domestic product (GDP) and summarised as the total mean percentage of GDP. The risk of bias of studies was assessed using the Larg and Moss method.

Results

We identified 14 095 articles, of which 24 studies met the eligibility criteria. Most studies had a low risk of bias. Of the 138 LMICs, data were available from 122 countries. The total annual absolute per capita cost ranged from US$590.78 for mild dementia to US$25 510.66 for severe dementia. Costs increased with the severity of dementia and the number of comorbidities. The estimated annual total national costs of dementia ranged from US$1.04 million in Vanuatu to US$195 billion in China. The average total national expenditure on dementia estimated as a proportion of GDP in LMICs was 0.45%. Indirect costs, on average, accounted for 58% of the total cost of dementia, while direct costs contributed 42%. Lack of nationally representative samples, variation in cost components, and quantification of indirect cost were the major methodological challenges identified in the existing studies.

Conclusion

The estimated costs of dementia in LMICs are lower than in high-income countries. Indirect costs contribute the most to the LMIC cost. Early detection of dementia and management of comorbidities is essential for reducing costs. The current costs are likely to be an underestimation due to limited dementia costing studies conducted in LMICs, especially in countries defined as low- income.

PROSPERO registration number

The protocol was registered in the International Prospective Register of Systematic Reviews database with registration number CRD42020191321.

Health economic benefits from optimized meal services to older adults-a literature-based synthesis

Malnutrition among older adults causes health problems and economic costs. Prevention of malnutrition through meal service can reduce such costs. This study estimates potential health economic benefits to be generated through meal service to home-dwelling older adults. The study contains three components: (1) systems analysis describing the relationship between meal service, nutritional status, health risk, and health-related costs, focusing on older adults, (2) a series of literature reviews to quantify the identified elements in each stage-subject combination: (i) meal service impact on nutrition status of older adults, (ii) associations between nutrition status and health risks, (iii) health care resource needs associated with these health risks, and (3) a model synthesis of literature findings to estimate the expected economic benefit of improved health status derived from meal service enrollment, using Denmark as an example. Expected economic benefits in terms of saved direct and indirect health care costs and improved quality-of-life was estimated at an amount of €307 per year per individual enrolled, of which direct health care cost savings constituted €75, while value of improved quality-of-life and reduced mortality constituted the rest. The average health economic benefit from enrolling older adults into meal service is likely to decrease with the number of subscribers. Findings like these are important to take into consideration, when making policy decisions regarding size of the meal service capacity, although it should be noted that the presented estimates are based on a number of assumptions of which some are subject to uncertainty.

The Business Process Model and Notation Used for the Representation of Alzheimer’s Disease Patients Care Process

Currently, the number of patients with neurological diseases is increasing, especially those older than 65 suffering from Alzheimer’s disease. This development increases the emphasis on understanding and mapping treatment and care processes, not only for the elderly. Service providers (of both treatment and care) are under general pressure to decrease charges and maintain or improve existing levels of care. This situation is significantly influenced by a comprehensive knowledge of the whole process and its values. This publication therefore aims to describe the fundamental procedural aspects of caring for patients with Alzheimer’s disease, using Business Process Model and Notation (BPMN). It also aims to show the possibilities of using BPMN in the description of treatment and care. Modeling of the business process is more frequently being applied not only by businesses but also by scientists involved in process models. It is used to model medical topics, with approximately 10% of its publications only, and most of these publications deal only with clinical pathways, not with overall treatment and care processes. However, the BPMN model allows the whole process of medical and nonmedical care for patients with Alzheimer’s disease to be described, including the decomposition of partial activities into individual threads and sub-processes or atomic tasks. This paper presents the BPMN modeling and mapping of the specific care path for neurodegenerative patients. The text provides a new perspective on the BPMN modeling of Alzheimer’s disease. The presented model offers the option of expanding treatment cost calculation to simulate the process using graphical tools and languages. The overall view of this system creates a much more complex concept of the system and its surroundings.

The main cost drivers in dementia: a systematic review

OBJECTIVES

Because of the increasing prevalence of dementia worldwide, combined with limited healthcare expenditures, a better understanding of the main cost drivers of dementia in different care settings is needed.

METHODS

A systematic review of cost-of-illness (COI) studies in dementia was conducted from 2003 to 2012, searching the following databases: PubMed (Medline), Cochrane Library, ScienceDirect (Embase) and National Health Service Economic Evaluations Database. Costs (per patient) by care setting were analyzed for total, direct, indirect and informal costs and related to the following: (1) cost perspective and (2) disease severity.

RESULTS

In total, 27 studies from 14 different healthcare systems were evaluated. In the included studies, total annual costs for dementia of up to $70,911 per patient (mixed setting) were estimated (average estimate of total costs = $30,554). The shares of cost categories in the total costs for dementia indicate significant differences for different care settings. Overall main cost drivers of dementia are informal costs due to home based long term care and nursing home expenditures rather than direct medical costs (inpatient and outpatient services, medication).

CONCLUSIONS

The results of this review highlight the significant economic burden of dementia for patients, families and healthcare systems and thus are important for future health policy planning. The significant variation of cost estimates for different care settings underlines the need to understand and address the financial burden of dementia from both perspectives. For health policy planning in dementia, future COI studies should follow a quality standard protocol with clearly defined cost components and separate estimates by care setting and disease severity.

Cost analysis of early psychosocial intervention in Alzheimer's disease

BACKGROUND/AIM

To investigate the impact of early psychosocial intervention aimed at patients with Alzheimer's disease (AD) and their caregivers on resource use and costs from a societal perspective.

METHODS

Dyads of patients and their primary caregiver were randomised to intervention (n = 163) or control (n = 167) and followed for 3 years. Health care use was extracted from national registers, and the Resource Utilisation in Dementia questionnaire was used to measure informal care and productivity loss. Multiple imputation was used to replace missing data, and non-parametric bootstrapping was used to estimate standard errors.

RESULTS

Overall, there were no statistically significant differences because of large variation in the observations. The average additional cost of psychosocial intervention provision was estimated at EUR 3,401 per patient. This cost masked a reduced use of formal health care and an increased use of informal care.

CONCLUSIONS

Early psychosocial intervention in AD could be cost-saving from a health care perspective, whereas the opposite seems to be true from a broader societal perspective.

The pharmacoeconomics of cognitive enhancers in moderate to severe Alzheimer's disease

Alzheimer's disease is associated with a substantial economic impact on patients, their caregivers and society. Due to the current rise in the aging population, the prevalence and impact of Alzheimer's disease are expected to increase greatly. The cost of caring for someone with Alzheimer's disease is magnified in the more severe stages of the disease. There are four cognitive enhancers commonly used for the treatment of Alzheimer's disease: three cholinesterase inhibitors (donepezil, rivastigmine and galantamine) and one NMDA receptor antagonist (memantine). Of these, donepezil and memantine have been approved in many countries as pharmacological treatments for moderate to severe Alzheimer's disease, while donepezil, rivastigmine and galantamine are approved treatments for mild to moderate Alzheimer's disease. While cost effectiveness has been well studied in mild to moderate Alzheimer's disease, the cost-benefit information for drug therapy in moderate to severe Alzheimer's disease is less clear. This article reviews the pharmacoeconomic data available on these four drugs, with a specific focus on moderate to severe Alzheimer's disease, including economic burden, cost drivers, clinical outcomes and pharmacoeconomic studies. A key driver of the cost of Alzheimer's disease is the severity of the disease, indicating that the ability to stabilize the disease state is a potential source of cost savings. Drug therapies that can limit increases in behavioural problems and cognitive and functional impairment, and postpone institutionalization without an increase in longevity may serve to reduce the economic burden on Alzheimer's disease patients. The data suggest that, while the available, approved agents offer only modest improvements in clinical outcomes, they could be cost-effective treatments for moderate to severe Alzheimer's disease when viewed from the societal perspective. For memantine and donepezil, data are available that suggest that the cost of these drugs is offset by the clinical and societal benefits provided by slowing the progression of Alzheimer's disease. While there are few head-to-head comparison trials, the similarity in costs of the treatments and efficacy against placebo suggest that cost effectiveness will not be substantially different among treatments. More studies that examine longitudinal resource utilization and its relationship to drug treatment in the moderate to severe stages are needed to clarify cost benefit in this population and possibly differentiate between individual medications.

Cost-of-illness studies of dementia: a systematic review focusing on stage dependency of costs

OBJECTIVE

To review cost-of-illness (COI) studies of dementia from Europe and North America which report costs per patient by disease stage.

METHOD

A systematic literature search was performed in electronic databases. Studies were classified according to important determinants of costs. Results were converted into year 2006 USD-PPP, and summarized as costs for formal and informal care in mild, moderate and severe dementia.

RESULTS

28 studies were evaluated. They used a wide range of methods. Costs more than doubled from mild to severe dementia. Patterns and size of estimated costs depended primarily on study objectives (estimation of total costs-net costs), living arrangements of patients (community-dwelling-institutionalized) and inclusion of informal care.

CONCLUSION

This review is the first to have focused on costs in different stages of dementia. The stage is an important determinant of costs. However, characteristics of individual studies need to be considered, when making use of their results.

Dementia care costs and the patient's quality of life (QoL) in Taiwan: home versus institutional care services

Organizing optimal care for demented older people is a complex health care issue. Controversies of service models for demented patients should be balanced between cost of care, placement, and quality of life (QoL). The main purpose of this study was to explore the optimal model of dementia care in Taiwan by evaluating the care cost, patients' QoL and healthcare settings. Overall, 140 pairs of demented patients and their primary informal caregivers were enrolled (89 community-living and 51 institute-living). Compared to institute-living subjects, community-living subjects were significantly better in cognition, physical function and QoL. The annual direct cost of institutional care was significantly higher than community care (464,193 New Taiwanese Dollar (NTD) vs. 144,047 (NTD), p<0.001), but indirect cost was significantly higher in home care (287,904 NTD vs. 35,665 NTD, p<0.001). The care cost of home care subjects with low physical dependence was significantly lower than institutional care subjects, but the care cost of home care subjects with high physical dependence was significantly higher than institutional care subjects. Physical dependence was the significant determinant of QoL for demented patients in this study. In conclusion, demented patients with low physical dependence may be cared in the communities with support and those who had high physical dependence may be cared in the institutes in terms of the balance of QoL and the care cost.

Private costs almost equal health care costs when intervening in mild Alzheimer's: a cohort study alongside the DAISY trial

Background

Alzheimer's disease is the leading cause of dementia and affects about 25 million people worldwide. Recent studies have evaluated the effect of early interventions for dementia, but few studies have considered private time and transportation costs associated with the intervention. This study assessed the total economic costs associated with a multifaceted intervention for mild Alzheimer's disease, including an estimate of the ratio of public to private costs.

Methods

The study sample comprised 163 dyads of patients and caregivers who received a multifaceted intervention of counselling sessions, courses and informational packages. The typical duration of the intervention was 7 months. A micro-costing approach was applied using prospectively collected data on resource utilisation that included estimates of participant time and transportation. Precision estimates were calculated using a bootstrapping technique and structural uncertainty was assessed with sensitivity analysis.

Results

The direct intervention cost was estimated at EUR 1,070 (95% CI 1,029;1,109). The total cost (including private costs) was estimated at EUR 2,020 (95% CI 1,929;2,106) i.e. the ratio of private to public costs was almost 1:1.

Conclusion

Intervention for mild Alzheimer's disease can be undertaken at a relatively low cost to public funds. However, policy planners should pay attention to the significant private costs associated with an intervention, which may ultimately pose a threat to equity in access to health care.

Trial registration

Current Controlled Trials ISRCTN74848736.

Direct costs associated with mild cognitive impairment in primary care

BACKGROUND/AIMS

Little is known about the direct costs of individuals with Mild Cognitive Impairment (MCI). This study investigates the direct costs associated with MCI according to recent diagnostic criteria from a societal perspective.

METHODS

Four hundred and fifty-two primary care patients aged 75+ from Leipzig, Germany, were investigated in face-to-face interviews regarding MCI according to the current diagnostic criteria of the International Working Group on MCI, resource utilisation and costs (questionnaire of service utilisation and costs), as well as chronic medical illness (Chronic Disease Score). Resource utilisation was monetarily valued using 2004/2005 prices.

RESULTS

Mean annual direct costs were 4,443 euro for patients with MCI (n=39) and 3,814 euro for patients without MCI (n=413) (p=0.34). Looking at the cost components, patients with and without MCI only significantly differed regarding pharmaceutical costs (1,210 euro vs 1,062 euro; p<0.05) not caused by antidementive drugs.

CONCLUSION

Direct costs of individuals having MCI are not significantly increased in comparison to direct costs of individuals without cognitive deficits.

Synthesis and Purification of Highly Hydrophobic Peptides Derived from the C-Terminus of Amyloid β-Protein

Some biotechnological inventions involve expensive, sophisticated machines. Others are relatively simple innovations that nevertheless address, and solve difficult problems. Synthesis and purification of highly hydrophobic peptides can be a difficult and challenging task, particularly when these peptides have low solubility in both aqueous and organic solvents. Here we describe the synthesis and purification of a series of peptides derived from the hydrophobic C-terminus of the 42-residue form of amyloid β-protein (Aβ42), a peptide believed to be the primary cause for Alzheimer's disease (AD). The series of C-terminal fragments (CTFs) had the general formula Aβ(x-42), x=28-39, which potentially can be used as inhibitors of Aβ42 assembly and neurotoxicity. Synthesis and purification of peptides containing 8-residues or less were straightforward. However, HPLC purification of longer peptides was problematic and provided <1% yield in particularly difficult cases due to very poor solubility in the solvent systems used both in reverse- and in normal phase chromatography. Modification of the purification protocol using water precipitation followed by removal of scavengers by washing with diethyl ether circumvented the need for HPLC purification and provided these peptides with purity as high as HPLC-purified peptides and substantially increased yield.

The cost-effectiveness of a behavior intervention with caregivers of patients with Alzheimer's disease

OBJECTIVES

To examine the cost-effectiveness of a randomized, clinical trial of a home-based intervention for caregivers of people with dementia.

DESIGN

This cost-effectiveness analysis examined Resources for Enhancing Alzheimer's Caregivers Health (REACH II), a multisite, randomized, clinical trial, from June 2002 through December 2004, funded by the National Institute on Aging and the National Institute of Nursing Research, of a behavioral intervention to decrease caregivers' stress and improve management of care recipient behavioral problems.

SETTING

Community-dwelling dementia caregiving dyads from the Memphis REACH II site.

PARTICIPANTS

Of Memphis' random sample of 55 intervention and 57 control black and white dyads, 46 in each arm completed without death or discontinuation. Family caregivers were aged 21 and older, lived with the care recipient, and had provided 4 or more hours of care per day for 6 months or longer. Care recipients were cognitively and functionally impaired.

INTERVENTION(S)

Twelve individual sessions (9 home sessions and 3 telephone sessions) supplemented by five telephone support-group sessions. Control caregivers received two "check in" phone calls.

MEASUREMENTS

Incremental cost-effectiveness ratio (ICER), the additional cost to bring about one additional unit of benefit (hours per day of providing care).

RESULTS

At 6 months, there was a significant difference between intervention caregivers and control caregivers in hours providing care (P=.01). The ICER showed that intervention caregivers had 1 extra hour per day not spent in caregiving, at a cost of $5 per day.

CONCLUSION

The intervention provided that most scarce of caregiver commodities--time. The emotional and physical costs of dementia caregiving are enormous, and this intervention was able to alleviate some of that cost.

The BRAINz trial: a novel approach to acetylcholinesterase-inhibitor treatment for Alzheimer’s disease

The only currently available treatments for Alzheimer’s disease (AD) are symptomatic, based on neurotransmitter modification. The most established of these are the cholinesterase inhibitors (ChEIs), which act at the synaptic level and cause a significant increase in the concentration of ACh in the brain. The efficacy of ChEIs is somewhat limited by gastrointestinal side effects that are often worsened by lack of compliance, which can be especially problematic in AD. Patients may refuse medication owing to impaired insight and the feeling that they do not need it, causing distress to carers, or they may simply forget, which is a major problem when treating patients who live alone. ZT-1, a prodrug of the ChEI huperzine, which has a long history of use in China, has demonstrated good efficacy and tolerability in its oral form in early trials in comparison with donepezil. To address the compliance issue, it is now being tested in a multinational study as a monthly subcutaneous implant. If successful this could, by its steady 24 h release, offer a major improvement in side effects, which are known to be related to fluctuating plasma levels. It will also aid compliance as it ensures regular dosing and takes away the onus of monitoring compliance from the carer, which in some cases may reduce carer stress.

The prevention of the dementia epidemic

Alzheimer's disease (AD) is considered to be the most common dementing disorder. The understanding of this disorder has greatly advanced over the past few years, and new therapeutic options have been developed. Another disorder, vascular dementia (VaD), is a syndrome with multiple etiologies operating through a variety of different mechanisms. The combination of AD and VaD is extremely common, making mixed dementia the most common type of dementia. Risk factors for VaD, which are the common vascular risk factors, are presently known to apply also to AD. Cholinergic deficits occur in both conditions. The identification of several genetic factors that can contribute to vascular damage, as well as possible auto-immune damage to vascular components, are important. It is remarkable that amyloid precursor protein (APP) mutations can cause the typical pathological changes of AD as well as amyloid deposition around blood vessels. These may lead to deficient blood perfusion to the brain, changes of the blood-brain barrier, as well as cerebral hemorrhages. Interestingly, attention to risk factors, such as hypertension, coronary artery disease, hyperlipidemia and smoking could reduce or delay the incidence of dementia, both vascular and AD.

Production, purification and functional validation of human secreted amyloid precursor proteins for use as neuropharmacological reagents

The secreted fragment of the amyloid precursor protein (sAPPalpha) generated following cleavage by alpha-secretase is an important mediator of cell function and is both neurotrophic and neuroprotective. HEK 293T cells have been stably integrated with a fragment of the APP gene to produce and secrete either sAPPalpha, or the alternative cleavage product sAPPbeta. Heparin binding domains on the proteins have been utilised to develop a one-step fast-performance-liquid-chromatography (FPLC) purification of sAPPs from the conditioned media. Immunoblotting analyses with a sAPP specific antibody coupled with highly sensitive silver staining techniques have validated the expression and purification strategy. Functional activity of the purified fragments was demonstrated by their ability to protect COS-7 and SH-SY5Y (neuroblastoma) cells against the adverse effects of glucose deprivation in a cell viability assay. The purified sAPPs also activated the NFkappaB transcription factor in COS-7 cells transfected with a luciferase reporter plasmid, with sAPPalpha the more potent activator as expected. The simple protocol to produce these mammalian expressed proteins will facilitate their use as potential neuropharmacological reagents in the elucidation of biochemical pathways modulated by sAPPs, and in the study of Alzheimer's disease mechanisms in general.

The Effect of a Memory Screening Program on the Early Diagnosis of Alzheimer Disease

CONTEXT

Alzheimer Disease (AD) is often diagnosed at a moderately advanced stage, even though its early detection has become increasingly important, because of the continuing development of treatments that may improve its outcome.

OBJECTIVE

To determine if a free memory screening program is associated with an earlier diagnosis of AD, compared with traditional referral methods, such as by physicians and family members.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective study of 1489 consecutive patients with AD who presented to an outpatient memory disorders clinic between 1993 and 2002. Subjects were classified according to referral source (memory screening, physician, family/friend, other), and self-reported ethnicity (white non-Hispanic, white Hispanic). The associations between referral source and the presenting cognitive and behavioral status of subjects were evaluated using analysis of variance and logistic regression analyses, after controlling for potentially confounding factors.

MAIN OUTCOME MEASURES

Score on the Folstein Mini-Mental State Examination (MMSE), duration of cognitive symptoms, and presence of psychosis, defined as delusions and/or hallucinations.

RESULTS

After controlling for ethnicity, gender, and the year of diagnosis, subjects with AD, who were referred by the memory screening program, scored significantly higher at presentation on the MMSE (20.8 +/- 5.7), than those referred by physicians (18.8 +/- 6.6), family/friends (16.8 +/- 6.6), or other referral sources (15.3 +/- 7.1). Subjects with AD, referred by the memory screening program, also had a lower reported duration of illness at presentation, and a decreased frequency of psychosis compared with those referred by family/friend and other methods. Other factors related to a diagnosis of AD at a later stage included female gender, Hispanic ethnicity, and a diagnosis early in the 1993 to 2002 time period.

CONCLUSIONS

The memory screening program referred patients with AD to a memory clinic at an earlier phase of illness compared with traditional methods such as physician referral.

The economic impact of neuropsychiatric symptoms in Alzheimer's disease: can drugs ease the burden?

The majority of patients with Alzheimer's disease (AD) will have clinically significant neuropsychiatric symptoms during the course of their disease. There is growing evidence that neuropsychiatric symptoms increase direct costs of care in patients with AD, especially the costs associated with formal long-term care and unpaid caregiving. For example, we have estimated that a 1-point worsening of the neuropsychiatric inventory score is associated with an incremental increase of between USD 247 and USD 409 per year in total direct costs of care based upon year 2001 US dollars, depending on the value of unpaid caregiving. Although data are still limited, there have been a series of well designed, controlled clinical trials that have established the efficacy of several drugs used in the treatment of neuropsychiatric symptoms in patients with AD. The economic impact of using efficacious drugs to treat neuropsychiatric symptoms in patients with AD has not been evaluated formally. To successfully complete formal economic evaluations of these drugs there is a need for more research to refine methods for determining the economic value of unpaid caregiving and to collect more data concerning the incremental effects of neuropsychiatric symptoms on QOL, costs of care and survival. The current ongoing treatment trials that are collecting economic and QOL data as a part of the trial will be able to perform cost-effectiveness and cost-utility analyses of these new efficacious drugs. These economic evaluations will provide important information for decision makers who are formulating healthcare policy for the treatment of patients with AD.

Cost effectiveness of cholinesterase inhibitors in the treatment of Alzheimer's disease: a review with methodological considerations

Cholinesterase inhibitors have been available for the treatment of Alzheimer's disease since 1993. They have significantly positive effects on cognitive functioning and other domains of functional capacity, such as activities of daily life in terms of efficacy, but the clinical value of these effects are under discussion. Cholinesterase inhibitors may also influence behavioural and psychological symptoms in Alzheimer's disease. Cholinesterase inhibitors are also regarded as rather expensive and, therefore, the question of cost effectiveness is essential. Pharmacoeconomic evaluations of cholinesterase inhibitors have so far been conducted in retrospect on efficacy data from prospective randomised clinical trials combined with economic data from other sources. There are no published specific cost-effectiveness studies of cholinesterase inhibitors which prospectively collected empirical data on costs and outcomes. There is only one published randomised clinical trial with such empirical data with a cost consequence analysis design, indicating cost neutrality. Several types of models to describe the long-term effects have been published, indicating cost effectiveness. However, due to methodological considerations, the validity of these models is difficult to judge. A research agenda for the cost effectiveness of cholinesterase inhibitors is proposed, including long-term studies with empirical data on resource use, costs and outcomes, studies on quality of life, informal care and behavioural and psychological symptoms, combination and comparative studies on mild cognitive impairment.