Economic evaluation of treatment options in patients with Alzheimer's disease: a systematic review of cost-effectiveness analyses

Economic evaluations of strategies targeting pre-diagnosis dementia populations: Protocol for a systematic review

Introduction

Dementia remains incurable, and treatment trials are typically conducted after the symptoms manifest, potentially too late in the disease process to alter its course. Early identification and intervention during the pre-diagnosis phase offer the potential to introduce more cost-effective strategies and enhance quality of life. This review aims to scrutinise emerging evidence and present a comprehensive summary of cost-effectiveness estimates of all strategies targeting the pre-diagnosis dementia population.

Method and analysis

A systematic search will be conducted across six electronic databases. All articles will be assessed against pre-defined eligibility criteria through title and abstract screening, and full-text screening phases. Data from the included articles will be extracted using a standardized template. A newly established framework based on the CHEERS 2022 checklist will be applied to assess the reporting quality of the included articles. The entire review process, from screening to data extraction and quality assessment, will be a dual process conducted by two reviewers. Disagreements will be resolved by a third senior reviewer. The extracted data will be synthesised and presented in tables and figures.

Conclusion

This systematic review will present evidence of cost-effectiveness, along with the strengths and limitations of the existing literature. These findings aim to identify existing gaps, thereby informing and guiding the design of future studies in this domain.

Ethics and dissemination

Since this is a systematic review protocol, ethical approval is not required. The results will be published in a peer-reviewed journal, with both raw and summarised data shared through the journal or other open platforms.

Systematic review registration

PROSPERO - CRD42024521521.

Barbiturate-sulfonate hybrids as potent cholinesterase inhibitors: design, synthesis and molecular modeling studies

Aim: Design and synthesis of a series of 5-benzylidene(thio)barbiturates 3a-r.Methodology: Evaluation of the inhibitory activity of the new chemical entities on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) using Donepezil as the standard reference.Results & Conclusion: Compound 3r emerged as the most potent AChE inhibitor (IC50 = 9.12 μM), while compound 3q exhibited the highest inhibitory activity against BChE (IC50 = 19.43 μM). Toxicological bioassays confirmed the absence of cytotoxicity for the most potent compounds at the tested doses. Molecular docking analysis demonstrated that the tested derivatives effectively bind to the active sites of both enzymes. Overall, this study sheds light on the potential of barbiturate-sulfonate conjugates as promising drug candidates.

Difference of Cerebrospinal Fluid Biomarkers and Neuropsychiatric Symptoms Profiles among Normal Cognition, Mild Cognitive Impairment, and Dementia Patient

The delineation of biomarkers and neuropsychiatric symptoms across normal cognition, mild cognitive impairment (MCI), and dementia stages holds significant promise for early diagnosis and intervention strategies. This research investigates the association of neuropsychiatric symptoms, evaluated via the Neuropsychiatric Inventory (NPI), with cerebrospinal fluid (CSF) biomarkers (Amyloid-β42, P-tau, T-tau) across a spectrum of cognitive states to enhance diagnostic accuracy and treatment approaches. Drawing from the National Alzheimer's Coordinating Center's Uniform Data Set Version 3, comprising 977 individuals with normal cognition, 270 with MCI, and 649 with dementia. To assess neuropsychiatric symptoms, we employed the NPI to understand the behavioral and psychological symptoms associated with each cognitive category. For the analysis of CSF biomarkers, we measured levels of Amyloid-β42, P-tau, and T-tau using the enzyme-linked immunosorbent assay (ELISA) and Luminex multiplex xMAP assay protocols. These biomarkers are critical in understanding the pathophysiological underpinnings of Alzheimer's disease and its progression, with specific patterns indicative of disease stage and severity. This study cohort consists of 1896 participants, which is composed of 977 individuals with normal cognition, 270 with MCI, and 649 with dementia. Dementia is characterized by significantly higher NPI scores, which are largely reflective of mood-related symptoms (p < 0.001). In terms of biomarkers, normal cognition shows median Amyloid-β at 656.0 pg/mL, MCI at 300.6 pg/mL, and dementia at 298.8 pg/mL (p < 0.001). Median P-tau levels are 36.00 pg/mL in normal cognition, 49.12 pg/mL in MCI, and 58.29 pg/mL in dementia (p < 0.001). Median T-tau levels are 241.0 pg/mL in normal cognition, 140.6 pg/mL in MCI, and 298.3 pg/mL in dementia (p < 0.001). Furthermore, the T-tau/Aβ-42 ratio increases progressively from 0.058 in the normal cognition group to 0.144 in the MCI group, and to 0.209 in the dementia group (p < 0.001). Similarly, the P-tau/Aβ-42 ratio also escalates from 0.305 in individuals with normal cognition to 0.560 in MCI, and to 0.941 in dementia (p < 0.001). The notable disparities in NPI and CSF biomarkers among normal, MCI and Alzheimer's patients underscore their diagnostic potential. Their combined assessment could greatly improve early detection and precise diagnosis of MCI and dementia, facilitating more effective and timely treatment strategies.

cCOG Web-Based Cognitive Assessment Tool

Cognitive testing is an essential part of clinical diagnostics and clinical trials in Alzheimer's disease. Digital cognitive tests hold a great opportunity to provide more versatile and cost-efficient patient pathways through flexible testing including at home. In this work, we describe a web-based cognitive test, cCOG, that can be used in screening, differential diagnosis, and monitoring the progression of neurodegenerative diseases.

Early start of anti-dementia medication is associated with lower health and social care costs in Alzheimer´s patients: a Finnish nationwide register study

OBJECTIVES

To evaluate the association between health and social care costs and early start of anti-dementia medication in a nationwide cohort of Finnish Alzheimer's disease (AD) patients.

METHODS

The cohort included 7454 Finnish AD patients who had their first AD diagnosis in 2012 and lived at home at the time of diagnosis. Data were collected retrospectively from the Finnish national health and social care registers. The primary outcome was 2-year cumulative direct costs after the incident AD diagnosis. The exploratory variable was early anti-dementia medication start (anti-dementia medication started within 3 months of the incident AD diagnosis). Sociodemographic variables, admission to 24-h care and care intensity level, as well as comorbidities were considered as adjusting variables.

RESULTS

Of all patients, 88.9% started AD medication within 3 months of diagnosis. The 2-year cumulative costs were €30,787 and €40,484 per patient for early and late starters, respectively. When adjusted for possible confounders, early start of anti-dementia medication was associated with 26.5% lower 2-year cumulative costs compared to late starters (relative cost 0.735; p < 0.001).

CONCLUSIONS

Early diagnosis and start of anti-dementia medication is important for managing the costs of increasing number of AD patients.

Determinants of approved acetylcholinesterase inhibitor response outcomes in Alzheimer's disease: relevance for precision medicine in neurodegenerative diseases

Acetylcholinesterase inhibitors (ChEI) are the global standard of care for the symptomatic treatment of Alzheimer's disease (AD) and show significant positive effects in neurodegenerative diseases with cognitive and behavioral symptoms. Although experimental and large-scale clinical evidence indicates the potential long-term efficacy of ChEI, primary outcomes are generally heterogeneous across outpatient clinics and regional healthcare systems. Sub-optimal dosing or slow tapering, heterogeneous guidelines about the timing for therapy initiation (prodromal versus dementia stages), healthcare providers' ambivalence to treatment, lack of disease awareness, delayed medical consultation, prescription of ChEI in non-AD cognitive disorders, contribute to the negative outcomes. We present an evidence-based overview of determinants, spanning genetic, molecular, and large-scale networks, involved in the response to ChEI in patients with AD and other neurodegenerative diseases. A comprehensive understanding of cerebral and retinal cholinergic system dysfunctions along with ChEI response predictors in AD is crucial since disease-modifying therapies will frequently be prescribed in combination with ChEI. Therapeutic algorithms tailored to genetic, biological, clinical (endo)phenotypes, and disease stages will help leverage inter-drug synergy and attain optimal combined response outcomes, in line with the precision medicine model.

Inhibitors of Cholinesterases in Pharmacology: the Current Trends

Inhibitors of cholinesterases are a wide group of low molecular weight compounds with a significant role in the current pharmacology. Besides the pharmacological importance, they are also known as toxic compounds like military nerve agents. In the pharmacology, drugs for Alzheimer disease, myasthenia gravis and prophylaxis of poisoning by nerve agents can be mentioned as the relevant applications. Besides this, anti-inflammation and antiphrastic drugs are other pharmacological applications of these inhibitors. This review is focused on a survey of cholinesterase inhibitors with known or expected pharmacological impact and indications of their use. Recent literature with comments is provided here as well.

Additive interaction of mid- to late-life depression and cerebrovascular disease on the risk of dementia: a nationwide population-based cohort study

Background

Dementia is a progressive neurocognitive disease with a substantial social burden. No apparent breakthroughs in treatment options have emerged so far; thus, disease prevention is essential for at-risk populations. Depression and cerebrovascular disease (CVD) are independent risk factors for dementia, but no studies have examined their interaction effect on dementia risk. This study aimed to identify the association of depression and CVD with the risk of dementia and evaluate whether dementia risk among patients with comorbid depression and CVD is higher than the sum of the individual risk due to each condition.

Methods

A population-based cohort study was conducted to analyze the Korean National Health Insurance Service-National Sample Cohort data of all individuals over 50 years of age. Individuals who had not been diagnosed with dementia at baseline were included and followed up from January 1, 2005, to December 31, 2013. A time-varying Cox proportional hazard regression model adjusted for potential confounding factors was used for the analysis. The interaction between depression and CVD was estimated based on the attributable proportion (AP), relative excess risk due to interaction (RERI), synergy index (SI), and multiplicative-scale interaction.

Results

A total of 242,237 participants were included in the analytical sample, of which 12,735 (5.3%) developed dementia. Compared to that for participants without depression or CVD, the adjusted hazard ratio for the incidence of dementia for those with depression alone was 2.35 (95% confidence interval [CI] 2.21–2.49), CVD alone was 3.25 (95% CI 3.11–3.39), and comorbid depression and CVD was 5.02 (95% CI 4.66–5.42). The additive interaction between depression and CVD was statistically significant (AP—0.08, 95% CI 0.01–0.16; RERI—0.42, 95% CI 0.03–0.82; SI—1.12, 95% CI 1.01–1.24). The multiplicative interaction was significant too, but the effect was negative (0.66, 95% CI 0.60–0.73).

Conclusions

In this population-based nationwide cohort with long-term follow-up, depression and CVD were associated with an increased risk of dementia, and their coexistence additively increased dementia risk more than the sum of the individual risks.

How Much Value Would a Treatment for Alzheimer's Disease Offer? Cost-Effectiveness Thresholds for Pricing a Disease-Modifying Therapy

BACKGROUND

Recent trials suggest that disease-modifying therapy (DMT) for Alzheimer's disease may become available soon. With the expected high price and a large patient pool, the budget impact will be substantial.

OBJECTIVE

We explore combinations of effectiveness and price under which a DMT is cost-effective.

METHODS

We used an open-source model to conduct two-way scenario analyses for both payer and societal perspectives, varying price, and treatment effect size simultaneously. The analysis generates costeffectiveness threshold prices over a potential range of DMT effectiveness in patients aged 65+ with mild cognitive impairment due to Alzheimer's disease in the US.

RESULTS

Under the willingness-to-pay a threshold of $150,000 per quality-adjusted life year and assuming 30% risk reduction relative to the standard of care, the maximum cost-effective price of a DMT per patient per year is ~$22,000 and ~$15,000 from societal and payer perspectives, respectively.

CONCLUSION

Joint variation of price and treatment effect size can help assess the cost-effectiveness of a potential Alzheimer's disease treatment.

Modeling Large Sparse Data for Feature Selection: Hospital Admission Predictions of the Dementia Patients Using Primary Care Electronic Health Records

A growing elderly population suffering from incurable, chronic conditions such as dementia present a continual strain on medical services due to mental impairment paired with high comorbidity resulting in increased hospitalization risk. The identification of at risk individuals allows for preventative measures to alleviate said strain. Electronic health records provide opportunity for big data analysis to address such applications. Such data however, provides a challenging problem space for traditional statistics and machine learning due to high dimensionality and sparse data elements. This article proposes a novel machine learning methodology: entropy regularization with ensemble deep neural networks (ECNN), which simultaneously provides high predictive performance of hospitalization of patients with dementia whilst enabling an interpretable heuristic analysis of the model architecture, able to identify individual features of importance within a large feature domain space. Experimental results on health records containing 54,647 features were able to identify 10 event indicators within a patient timeline: a collection of diagnostic events, medication prescriptions and procedural events, the highest ranked being essential hypertension. The resulting subset was still able to provide a highly competitive hospitalization prediction (Accuracy: 0.759) as compared to the full feature domain (Accuracy: 0.755) or traditional feature selection techniques (Accuracy: 0.737), a significant reduction in feature size. The discovery and heuristic evidence of correlation provide evidence for further clinical study of said medical events as potential novel indicators. There also remains great potential for adaption of ECNN within other medical big data domains as a data mining tool for novel risk factor identification.

cCOG: A web-based cognitive test tool for detecting neurodegenerative disorders

INTRODUCTION

Web-based cognitive tests have potential for standardized screening in neurodegenerative disorders. We examined accuracy and consistency of cCOG, a computerized cognitive tool, in detecting mild cognitive impairment (MCI) and dementia.

METHODS

Clinical data of 306 cognitively normal, 120 mild cognitive impairment (MCI), and 69 dementia subjects from three European cohorts were analyzed. Global cognitive score was defined from standard neuropsychological tests and compared to the corresponding estimated score from the cCOG tool containing seven subtasks. The consistency of cCOG was assessed comparing measurements administered in clinical settings and in the home environment.

RESULTS

cCOG produced accuracies (receiver operating characteristic-area under the curve [ROC-AUC]) between 0.71 and 0.84 in detecting MCI and 0.86 and 0.94 in detecting dementia when administered at the clinic and at home. The accuracy was comparable to the results of standard neuropsychological tests (AUC 0.69-0.77 MCI/0.91-0.92 dementia).

DISCUSSION

cCOG provides a promising tool for detecting MCI and dementia with potential for a cost-effective approach including home-based cognitive assessments.

The cholinergic system in the pathophysiology and treatment of Alzheimer's disease

Cholinergic synapses are ubiquitous in the human central nervous system. Their high density in the thalamus, striatum, limbic system, and neocortex suggest that cholinergic transmission is likely to be critically important for memory, learning, attention and other higher brain functions. Several lines of research suggest additional roles for cholinergic systems in overall brain homeostasis and plasticity. As such, the brain's cholinergic system occupies a central role in ongoing research related to normal cognition and age-related cognitive decline, including dementias such as Alzheimer's disease. The cholinergic hypothesis of Alzheimer's disease centres on the progressive loss of limbic and neocortical cholinergic innervation. Neurofibrillary degeneration in the basal forebrain is believed to be the primary cause for the dysfunction and death of forebrain cholinergic neurons, giving rise to a widespread presynaptic cholinergic denervation. Cholinesterase inhibitors increase the availability of acetylcholine at synapses in the brain and are one of the few drug therapies that have been proven clinically useful in the treatment of Alzheimer's disease dementia, thus validating the cholinergic system as an important therapeutic target in the disease. This review includes an overview of the role of the cholinergic system in cognition and an updated understanding of how cholinergic deficits in Alzheimer's disease interact with other aspects of disease pathophysiology, including plaques composed of amyloid-β proteins. This review also documents the benefits of cholinergic therapies at various stages of Alzheimer's disease and during long-term follow-up as visualized in novel imaging studies. The weight of the evidence supports the continued value of cholinergic drugs as a standard, cornerstone pharmacological approach in Alzheimer's disease, particularly as we look ahead to future combination therapies that address symptoms as well as disease progression.

Heterogeneity in Cost-Effectiveness Analysis of Vaccination for Mild and Moderate Alzheimer's Disease

BACKGROUND

Immunotherapy for Alzheimer's disease(AD) has gained momentum in recent years. One of the concerns over its application pertains to Cost-Effectiveness Analysis (CEA) from population average and specific subgroup differences, as such a therapy is imperative for health decisionmakers to allocate limited resources. However, this sort of CEA model considering heterogeneous population with risk factors adjustment has been rarely addressed.

METHODS

We aimed to show the heterogeneity of CEA in immunotherapy for AD in comparison with the comparator without intervention. Economic evaluation was performed via incremental Cost- Effectiveness Ratio (ICER) and Cost-Effectiveness Acceptability Curve (CEAC) in terms of the Quality- Adjusted Life Years (QALY). First, population-average CEA was performed with and without adjustment for age and gender. Secondly, sub-group CEA was performed with the stratification of gender and age based on Markov process.

RESULTS

Given the threshold of $20,000 of willingness to pay, the results of ICER without and with adjustment for age and gender revealed similar results ($14,691/QALY and $17,604/QALY). The subgroup ICER results by different age groups and gender showed substantial differences. The CEAC showed that the probability of being cost-effective was only 48.8%-53.3% in terms of QALY at population level but varied from 83.5% in women aged 50-64 years, following women aged 65-74 years and decreased to 0.2% in men≥ 75 years.

CONCLUSION

There were considerable heterogeneities observed in the CEA of vaccination for AD. As with the development of personalized medicine, the CEA results assessed by health decision-maker should not only be considered by population-average level but also specific sub-group levels.

Can magnesium reduce central neurodegeneration in Alzheimer's disease? Basic evidences and research needs

Magnesium (Mg) is a crucial divalent cation with more than 300 cellular functions. This ion shows therapeutic properties in several neurological diseases. Although there are numerous basic evidences showing that Mg can inhibit pathological processes involved in neuroglial degeneration, this low-cost option is not well-considered in clinical research and practice for now. Nevertheless, none of the expensive drugs currently recommended by the classic guidelines (in addition to physiological rehabilitation) had shown exceptional effectiveness. Herein, focusing on Alzheimer's disease (AD), we analyze the therapeutic pathways that support the use of Mg for neurogenesis and neuroprotection. According to experimental findings reviewed, Mg shows interesting abilities to facilitate toxin clearance, reduce neuroinflammation, inhibit the pathologic processing of amyloid protein precursor (APP) as well as the abnormal tau protein phosphorylation, and to reverse the deregulation of N-methyl-D-aspartate receptors. Currently, some crucial details of the mechanisms involved in these proved effects remain elusive and clinical background is poor. Therefore, further studies are required to enable a better overview on pharmacodynamic targets of Mg and thus, to find optimal pharmacologic strategies for clinical use of this ion.

Modelling long-term cost-effectiveness of health promotion for community-dwelling older people

The effectiveness of health promotion for community-dwelling older people is well documented; however, there is a general lack of health economic evaluations. The aim of the present study was to evaluate long-term cost-effectiveness over 4 years of two health promoting interventions: senior meetings and a preventive home visit, for community-dwelling older people in relation to no intervention. We applied a Markov model including five states defined in relation to level of dependency of home help and place of residency. The model included transitions between dependency states, scores for quality of life and societal costs for each state, intervention costs and intervention effects for two formats of health promoting interventions. For each intervention and a no-intervention control group, we calculated the accumulated quality-adjusted life years (QALYs) and societal costs over 4 years. Sensitivity analyses included higher intervention costs, lower intervention effects and additional intervention costs and effects related to booster sessions. The results of all analyses indicated that health promotion implemented for community-dwelling older people in the format of senior meetings or a preventive home visit was cost-effective. Both interventions lead to QALY gains and reduce societal costs at any follow-up over 4 years, and thus, resources can be used to implement other interventions. The most important factor for the magnitude of QALY gains and cost savings was the intervention effect. Yearly booster sessions implemented for those persons who maintained their level of functioning extended the intervention effects adding additional QALYs and further reducing societal costs.

A pharmacoeconomic evaluation of cholinesterase inhibitors and memantine for the treatment of Alzheimer's disease

INTRODUCTION

Alzheimer's disease (AD) results in progressively worsening cognitive decline, leading to loss of functional ability, behavior/mood disturbances, institutionalization, and death. Current pharmaceutical therapies only treat the symptoms of cognitive decline yet can be expensive for payers. Areas covered: The authors undertook a systematic review of economic evaluations of pharmaceutical therapies for AD. The literature search encompassed English-language studies indexed in PubMed (Medline), Cochrane Library Current, and Web of Science. The search included articles published between 1 January 1995 and 10 February 2018. The literature suggested AD medications generally dominated comparator treatments (e.g. placebo). Expert opinion: The authors noted several limitations of the included economic evaluations. These limitations suggest the results of the economic evaluations should be interpreted with caution. Many economic models were not transparent with respect to sources of probabilities and cost data, and data collected in certain jurisdictions were applied to other jurisdictions without considering the validity of such applications. Measuring health utilities in cognitively impaired populations raises questions about the validity of quality-adjusted life years, but this issue was unaddressed in the included studies. Most included studies were sponsored by industry and the results tended to overwhelmingly support the manufacturer's product.

Circadian Rhythm and Alzheimer's Disease

Alzheimer’s disease (AD) is a neurodegenerative disorder with a growing epidemiological importance characterized by significant disease burden. Sleep-related pathological symptomatology often accompanies AD. The etiology and pathogenesis of disrupted circadian rhythm and AD share common factors, which also opens the perspective of viewing them as a mutually dependent process. This article focuses on the bi-directional relationship between these processes, discussing the pathophysiological links and clinical aspects. Common mechanisms linking both processes include neuroinflammation, neurodegeneration, and circadian rhythm desynchronization. Timely recognition of sleep-specific symptoms as components of AD could lead to an earlier and correct diagnosis with an opportunity of offering treatments at an earlier stage. Likewise, proper sleep hygiene and related treatments ought to be one of the priorities in the management of the patient population affected by AD. This narrative review brings a comprehensive approach to clearly demonstrate the underlying complexities linking AD and circadian rhythm disruption. Most clinical data are based on interventions including melatonin, but larger-scale research is still scarce. Following a pathophysiological reasoning backed by evidence gained from AD models, novel anti-inflammatory treatments and those targeting metabolic alterations in AD might prove useful for normalizing a disrupted circadian rhythm. By restoring it, benefits would be conferred for immunological, metabolic, and behavioral function in an affected individual. On the other hand, a balanced circadian rhythm should provide greater resilience to AD pathogenesis.

Alzheimer's disease Archimedes condition-event simulator: Development and validation

Introduction

Several advances have been made in Alzheimer's Disease (AD) modeling, however, there remains a need for a simulator that represents the full scope of disease progression and can be used to study new disease-modifying treatments for early-stage and even prodromal AD.

Methods

We developed AD Archimedes condition-event simulator, a patient-level simulator with a focus on simulating the effects of early interventions through changes in biomarkers of AD. The simulator incorporates interconnected predictive equations derived from longitudinal data sets.

Results

The results of external validations on AD Archimedes condition-event simulator showed that it provides reasonable estimates once compared to literature results on transition to dementia AD, institutionalization, and mortality. A case study comparing a disease-modifying treatment and a symptomatic treatment also showcases the benefits of early treatment.

Discussion

The AD Archimedes condition-event simulator is designed to perform economic evaluation on various interventions through close tracking of disease progression and the related clinical outcomes.

Non-Pharmacologic Interventions for Older Adults with Subjective Cognitive Decline: Systematic Review, Meta-Analysis, and Preliminary Recommendations

In subjective cognitive decline (SCD), older adults present with concerns about self-perceived cognitive decline but are found to have clinically normal function. However, a significant proportion of those adults are subsequently found to develop mild cognitive impairment, Alzheimer's dementia or other neurocognitive disorder. In other cases, SCD may be associated with mood, personality, and physical health concerns. Regardless of etiology, adults with SCD may benefit from interventions that could enhance current function or slow incipient cognitive decline. The objective of this systematic review and meta-analysis, conducted in accordance with the PRISMA guidelines, is to examine the benefits of non-pharmacologic intervention (NPI) in persons with SCD. Inclusion criteria were studies of adults aged 55 + with SCD defined using published criteria, receiving NPI or any control condition, with cognitive, behavioural, or psychological outcomes in controlled trails. Published empirical studies were obtained through a standardized search of CINAHL Complete, Cochrane Central Register of Controlled Trials, MEDLINE with Full Text, PsycINFO, and PsycARTICLES, supplemented by a manual retrieval of relevant articles. Study quality and bias was determined using PEDro. Nine studies were included in the review and meta-analysis. A wide range of study quality was observed. Overall, a small effect size was found on cognitive outcomes, greater for cognitive versus other intervention types. The available evidence suggests that NPI may benefit current cognitive function in persons with SCD. Recommendations are provided to improve future trials of NPI in SCD.

Elevated OPRD1 promoter methylation in Alzheimer's disease patients

Aberrant DNA methylation has been observed in the patients with Alzheimer’s disease (AD), a common neurodegenerative disorder in the elderly. OPRD1 encodes the delta opioid receptor, a member of the opioid family of G-protein-coupled receptors. In the current study, we compare the DNA methylation levels of OPRD1 promoter CpG sites (CpG1, CpG2, and CpG3) between 51 AD cases and 63 controls using the bisulfite pyrosequencing technology. Our results show that significantly higher CpG3 methylation is found in AD cases than controls. Significant associations are found between several biochemical parameters (including HDL-C and ALP) and CpG3 methylation. Subsequent luciferase reporter gene assay shows that DNA fragment containing the three OPRD1 promoter CpGs is able to regulate gene expression. In summary, our results suggest that OPRD1 promoter hypermethylation is associated with the risk of AD.

Current issues and future research priorities for health economic modelling across the full continuum of Alzheimer's disease

Available data and models for the health-economic evaluation of treatment in Alzheimer's disease (AD) have limitations causing uncertainty to decision makers. Forthcoming treatment strategies in preclinical or early AD warrant an update on the challenges associated with their economic evaluation. The perspectives of the co-authors were complemented with a targeted review of literature discussing methodological issues and data gaps in AD health-economic modelling. The methods and data available to translate treatment efficacy in early disease into long-term outcomes of relevance to policy makers and payers are limited. Current long-term large-scale data accurately representing the continuous, multifaceted, and heterogeneous disease process are missing. The potential effect of disease-modifying treatment on key long-term outcomes such as institutionalization and death is uncertain but may have great effect on cost-effectiveness. Future research should give priority to collaborative efforts to access better data on the natural progression of AD and its association with key long-term outcomes.

Cost effectiveness of an intervention focused on reducing bathing disability

The onset of bathing disability among older people is critical for a decline in functioning and has implications for both the individuals’ quality of life and societal costs. The aim of this study was to evaluate long-term cost effectiveness of an intervention targeting bathing disability among older people. For hypothetical cohorts of community-dwelling older people with bathing disability, transitions between states of dependency and death were modelled over 8 years including societal costs. A five-state Markov model based on states of dependency was used to evaluate Quality-adjusted life years (QALYs) and costs from a societal perspective. An intervention group was compared with a no intervention control group. The intervention focused on promoting safe and independent performance of bathing-related tasks. The intervention effect, based on previously published trials, was applied in the model as a 1.4 increased probability of recovery during the first year. Over the full follow-up period, the intervention resulted in QALY gains and reduced societal cost. After 8 years, the intervention resulted in 0.052 QALYs gained and reduced societal costs by €2410 per person. In comparison to the intervention cost, the intervention effect was a more important factor for the magnitude of QALY gains and long-term societal costs. The intervention cost had only minor impact on societal costs. The conclusion was that an intervention targeting bathing disability among older people presents a cost-effective use of resources and leads to both QALY gains and reduced societal costs over 8 years.

Systematic Review of Model-Based Economic Evaluations of Treatments for Alzheimer's Disease

BACKGROUND

Numerous economic evaluations using decision-analytic models have assessed the cost effectiveness of treatments for Alzheimer's disease (AD) in the last two decades. It is important to understand the methods used in the existing models of AD and how they could impact results, as they could inform new model-based economic evaluations of treatments for AD.

OBJECTIVE

The aim of this systematic review was to provide a detailed description on the relevant aspects and components of existing decision-analytic models of AD, identifying areas for improvement and future development, and to conduct a quality assessment of the included studies.

METHODS

We performed a systematic and comprehensive review of cost-effectiveness studies of pharmacological treatments for AD published in the last decade (January 2005 to February 2015) that used decision-analytic models, also including studies considering patients with mild cognitive impairment (MCI). The background information of the included studies and specific information on the decision-analytic models, including their approach and components, assumptions, data sources, analyses, and results, were obtained from each study. A description of how the modeling approaches and assumptions differ across studies, identifying areas for improvement and future development, is provided. At the end, we present our own view of the potential future directions of decision-analytic models of AD and the challenges they might face.

RESULTS

The included studies present a variety of different approaches, assumptions, and scope of decision-analytic models used in the economic evaluation of pharmacological treatments of AD. The major areas for improvement in future models of AD are to include domains of cognition, function, and behavior, rather than cognition alone; include a detailed description of how data used to model the natural course of disease progression were derived; state and justify the economic model selected and structural assumptions and limitations; provide a detailed (rather than high-level) description of the cost components included in the model; and report on the face-, internal-, and cross-validity of the model to strengthen the credibility and confidence in model results. The quality scores of most studies were rated as fair to good (average 87.5, range 69.5-100, in a scale of 0-100).

CONCLUSION

Despite the advancements in decision-analytic models of AD, there remain several areas of improvement that are necessary to more appropriately and realistically capture the broad nature of AD and the potential benefits of treatments in future models of AD.

Therapeutic drug monitoring for patients with Alzheimer dementia to improve treatment with donepezil

BACKGROUND

Aiming to verify that therapeutic drug monitoring has the potential to optimize treatment with acetylcholine esterase inhibitors of patients with Alzheimer dementia, this study investigated whether serum concentrations of donepezil are associated with clinical improvement.

METHODS

Clinical improvement was measured using the clinical global impression (CGI) scale, and donepezil concentrations were measured in serum by a high-performance liquid chromatographic method with spectrophotometric detection.

RESULTS

In total, 206 serum samples from 106 patients (49.5% female) were retrospectively available for analysis. Patients included were treated under everyday conditions. Their mean ± SD age was 72 ± 9 years, daily doses of donepezil were 5 and 10 mg, and their mean ± SD serum concentrations were 23 ± 9 and 47 ± 18 ng/mL, respectively. Serum concentrations correlated significantly (P < 0.001) with CGI scores (Pearson's correlation coefficient r = 0.511, P < 0.01). In patients who were "very much improved," according to their CGI score, the mean serum concentration was 66 ± 20 ng/mL and thus significantly higher (P < 0.01) than in patients with "minimal improvement" (29 ± 12 ng/mL). Receiver operating characteristics analysis suggests that donepezil serum concentrations of at least 50 ng/mL may be recommended for maximal clinical benefit.

CONCLUSIONS

Because donepezil serum concentrations were highly variable between individual patients and the majority of patients exhibited concentrations that were below 50 ng/mL at therapeutic doses of 5 and 10 mg/d, it can be concluded that therapeutic drug monitoring may be used to enhance the effectiveness of donepezil treatment.

Increased Long-Term Risk of Dementia in Patients With Carbon Monoxide Poisoning: A Population-Based Study

Carbon monoxide (CO) poisoning may cause toxicity of the central nervous system and heart. However, the association between CO poisoning and long-term dementia risk remains unestablished. We investigated the incidence of dementia in patients with CO poisoning in Taiwan and evaluated whether they had a higher risk of dementia than did the general population.A nationwide population-based cohort study was conducted among patients with CO poisoning identified using Taiwan's National Health Insurance Research Database (NHIRD) during 2004 to 2013. CO poisoning was defined according to the International Classification of Diseases, Ninth Revision, Clinical Modification codes. The study cohort comprised patients with CO poisoning between 2005 and 2010 (N = 14,590). Each patient was age-, sex-, and index date-matched with 4 randomly selected controls from the comparison cohort (N = 58,360). All patients were followed from the study date until dementia development, death, or the end of 2013. Cox proportional hazards regressions were performed for comparing the hazard ratios for dementia between the 2 cohorts.Incident cases of dementia were identified from the NHIRD.After adjustment for potential confounders, the study cohort was independently associated with a higher dementia risk (adjusted hazard ratio, 2.75; 95% confidence interval, 2.26-3.35).This population-based cohort study indicated that patients with CO poisoning have a higher risk of dementia than do people without CO poisoning.

Probabilistic Cost-Effectiveness Analysis of Vaccination for Mild or Moderate Alzheimer's Disease

BACKGROUND

Studies on the immunotherapy for Alzheimer's disease (AD) have increasingly gained attention since 1990s. However, there are pros (preventing of AD) and cons (incurred cost and side effects) regarding the administration of immunotherapy. Up to date, there has been lacking of economic evaluation for immunotherapy of AD. We aimed to assess the cost-effectiveness analysis of the vaccination for AD.

METHODS

A meta-analysis of randomized control trials after systemic review was conducted to evaluate the efficacy of the vaccine. A Markov decision model was constructed and applied to a 120,000-Taiwanese cohort aged ≥65 years. Person years and quality-adjusted life years (QALY) were computed between the vaccinated group and the the unvaccinated group. Economic evaluation was performed to calculate the incremental cost-effectiveness ratio (ICER) and cost-effectiveness acceptability curve (CEAC).

RESULTS

Vaccinated group gained an additional 0.84 life years and 0.56 QALYs over 10-years and an additional 0.35 life years and 0.282 QALYs over 5-years of follow-up. The vaccinated group dominated the unvaccinated group by ICER over 5-years of follow-up. The ICERs of 10-year follow-up for the vaccinated group against the unvaccinated group were $13,850 per QALY and $9,038 per life year gained. Given the threshold of $20,000 of willingness to pay (WTP), the CEAC showed the probability of being cost-effective for vaccination with QALY was 70.7% and 92% for life years gained after 10-years of follow-up. The corresponding figures were 87.3% for QALY and 93.5% for life years gained over 5-years follow-up.

CONCLUSION

The vaccination for AD was cost-effective in gaining QALY and life years compared with no vaccination, under the condition of a reasonable threshold of WTP.

Benefits and risks of add-on therapies for Alzheimer's disease

Despite three decades of intensive research, the efforts of scientific society and industry and the expenditures, numerous attempts to develop effective treatments for Alzheimer's disease have failed. Currently, approved and widely used medications to treat cognitive deficits in Alzheimer's disease are symptomatic only and show at best modest efficacy. In this context, the need to develop a successful, disease-modifying treatment is loudly expressed. One way to achieve this goal is the use of add-on therapies or various combinations of existing ‘conventional’ drugs. Results of several clinical studies and post hoc analyses of combination therapy with all cholinesterase inhibitors and memantine are published. Moreover, there is a need for studies on long-term efficacy of combination therapy in Alzheimer's.

Impact of 6-month aerobic exercise on Alzheimer's symptoms

Little is known about how aerobic exercise affects Alzheimer's disease (AD). The purpose of this pilot study was to test the impact of 6-month cycling on AD symptoms in community-dwelling older adults with mild-to-moderate AD, using a single-group, repeated-measures design (n = 26). AD symptoms were measured with the AD Assessment Scale-Cognitive (ADAS-Cog), Disability in AD (DAD), and Neuropsychiatric Inventory-Caregiver (NPI-Q) scales at baseline, 3 and 6 months. Data were analyzed using mixed linear models. The ADAS-Cog, DAD, and NPI-Q severity scores remained unchanged over the 6-month period, while caregiver distress decreased 40% (p < .05). We conclude that aerobic exercise may reduce AD symptoms and appears effective in decreasing caregiver distress. Further randomized controlled trials are needed to examine the effects of aerobic exercise in AD.

Cost-utility analysis of memantine extended release added to cholinesterase inhibitors compared to cholinesterase inhibitor monotherapy for the treatment of moderate-to-severe dementia of the Alzheimer's type in the US

OBJECTIVE

This study evaluates the cost-effectiveness of memantine extended release (ER) as an add-on therapy to acetylcholinesterase inhibitor (AChEI) [combination therapy] for treatment of patients with moderate-to-severe Alzheimer's disease (AD) from both a healthcare payer and a societal perspective over 3 years when compared to AChEI monotherapy in the US.

METHODS

A phase III trial evaluated the efficacy and safety of memantine ER for treatment of AD patients taking an AChEI. The analysis assessed the long-term costs and health outcomes using an individual patient simulation in which AD progression is modeled in terms of cognition, behavior, and functioning changes. Input parameters are based on patient-level trial data, published literature, and publicly available data sources. Changes in anti-psychotic medication use are incorporated based on a published retrospective cohort study. Costs include drug acquisition and monitoring, total AD-related medical care, and informal care associated with caregiver time. Incremental cost-utility ratio (ICUR), life years, care time for caregiver, time in community and institution, time on anti-psychotics, time by disease severity, and time without severe symptoms are reported. Costs and health outcomes are discounted at 3% per annum.

RESULTS

Considering a societal perspective over 3 years, this analysis shows that memantine ER combined with an AChEI provides better clinical outcomes and lower costs than AChEI monotherapy. Discounted average savings were estimated at $18,355 and $20,947 per patient and quality-adjusted life-years (QALYs) increased by an average of 0.12 and 0.13 from a societal and healthcare payer perspective, respectively. Patients on combination therapy spent an average of 4 months longer living at home and spend less time in moderate-severe and severe stages of the disease.

CONCLUSION

Combination therapy for patients with moderate-to-severe AD is a cost-effective treatment compared to AChEI monotherapy in the US.

Cognition enhancers for the treatment of dementia

Dementia is a broad term used to describe several chronic progressive neurological disorders that adversely affect higher mental functions including memory, language, behaviour, abstract thinking, comprehension, calculation, learning capacity and judgement. Alzheimer's disease is the most common form of dementia but other neurological conditions such as Parkinson's disease, cerebrovascular disease and chronic infections such as syphilis can also lead to the clinical syndrome of dementia. Initial investigations should always focus on finding any treatable cause for dementia such as HIV, structural lesions such as subdural haematomas or specific nutritional deficiency states such as that due to vitamin B12 and treated appropriately. Where no treatable or reversible aetiology is found, a referral to a specialist should be considered who may initiate further investigations including magnetic resonance imaging or perfusion single-photon emission computerised tomography scans of the brain, and sometimes cerebrospinal fluid examination or an electroencephalogram.

The development of small molecule angiotensin IV analogs to treat Alzheimer's and Parkinson's diseases

Alzheimer's (AD) and Parkinson's (PD) diseases are neurodegenerative diseases presently without effective drug treatments. AD is characterized by general cognitive impairment, difficulties with memory consolidation and retrieval, and with advanced stages episodes of agitation and anger. AD is increasing in frequency as life expectancy increases. Present FDA approved medications do little to slow disease progression and none address the underlying progressive loss of synaptic connections and neurons. New drug design approaches are needed beyond cholinesterase inhibitors and N-methyl-d-aspartate receptor antagonists. Patients with PD experience the symptomatic triad of bradykinesis, tremor-at-rest, and rigidity with the possibility of additional non-motor symptoms including sleep disturbances, depression, dementia, and autonomic nervous system failure. This review summarizes available information regarding the role of the brain renin-angiotensin system (RAS) in learning and memory and motor functions, with particular emphasis on research results suggesting a link between angiotensin IV (AngIV) interacting with the AT4 receptor subtype. Currently there is controversy over the identity of this AT4 receptor protein. Albiston and colleagues have offered convincing evidence that it is the insulin-regulated aminopeptidase (IRAP). Recently members of our laboratory have presented evidence that the brain AngIV/AT4 receptor system coincides with the brain hepatocyte growth factor/c-Met receptor system. In an effort to resolve this issue we have synthesized a number of small molecule AngIV-based compounds that are metabolically stable, penetrate the blood-brain barrier, and facilitate compromised memory and motor systems. These research efforts are described along with details concerning a recently synthesized molecule, Dihexa that shows promise in overcoming memory and motor dysfunctions by augmenting synaptic connectivity via the formation of new functional synapses.

New animal models of Alzheimer's disease that display insulin desensitization in the brain

Alzheimer's disease (AD) is a complex neurodegenerative disorder, which involves many underlying pathological processes. Recently, it has been demonstrated that AD also includes impairments of insulin signaling in the brain. Type 2 diabetes is a risk factor for AD, and AD and diabetes share a number of pathologies. The classical hallmarks of AD are senile plaques and neurofibrillary tangles, which consist of amyloid-β and hyperphosphorylated tau. Based on the two hallmarks, transgenic animal models of AD have been developed, which express mutant human genes of amyloid precursor protein, presenilin-1/2, and tau. It is likely that these mouse models are too limited in their pathology. In this work, we describe mouse models that model diabetes and show insulin signaling impairment as well as neurodegenerative pathologies that are similar to those seen in the brains of AD patients. The combination of traditional AD mouse models with induced insulin impairments in the brain may be a more complete model of AD. Interestingly, AD mouse models treated with drugs that have been developed to cure type 2 diabetes have shown impressive outcomes. Based on these findings, several ongoing clinical trials are testing long lasting insulin analogues or GLP-1 mimetics in patients with AD.

Consumption trends for specific drugs used to treat dementia in the region of Madrid (Spain) from 2002 to 2012

INTRODUCTION

Analysing drug consumption in large population groups lets us observe consumption trends and compare them between different settings.

OBJECTIVE

to analyse the time trends for consumption and costs of specific drugs used to treat dementia in the region of Madrid (Spain) and compare trends by sex and age cohort.

METHODS

Descriptive study of cholinesterase inhibitors (N06DA) and memantine (N06DX01) dispensed in Madrid between 2002 and 2012 and covered by the Spain's national health system. Consumption was calculated by analysing changes in DDD (defined daily doses) to find total and yearly increases. The cost was estimated based on DDD price. To compare consumption rates by age and sex, we calculated DDD per 100 inhabitants/day.

RESULTS

Between 2002 and 2012, consumption of drugs used to treat dementia increased sixfold. During this period, cholinesterase inhibitors accounted for 76.70% of the drugs consumed and memantine, 23.30%. The estimated cost rose by a by a factor of 5.7 over 11 years (or by a factor of 4 taking into account the use of generic drugs). In 2012, 2.42% of the patients aged 65 or over consumed cholinesterase inhibitors (women 2.82%, men 1.83%) and 0.90% consumed memantine (women 1.10%, men 0.61%). Consumption increased in age cohorts up to 86 to 90 (5.84% for cholinesterase inhibitors and 2.33% for memantine) and declined thereafter.

CONCLUSIONS

Consumption of cholinesterase inhibitors and memantine gradually increased, but consumption in 2012 did not reach levels equivalent to dementia prevalence figures. Pharmaceutical expenditure restraint measures may temporarily slow the cost increase temporarily but if the same trend of consumption persists, costs will rise.

Structure of N-terminal sequence Asp-Ala-Glu-Phe-Arg-His-Asp-Ser of Aβ-peptide with phospholipase A2 from venom of Andaman Cobra sub-species Naja naja sagittifera at 2.0 Å resolution

Alzheimer’s disease (AD) is one of the most significant social and health burdens of the present century. Plaques formed by extracellular deposits of amyloid β (Aβ) are the prime player of AD’s neuropathology. Studies have implicated the varied role of phospholipase A₂ (PLA₂) in brain where it contributes to neuronal growth and inflammatory response. Overall contour and chemical nature of the substrate-binding channel in the low molecular weight PLA₂s are similar. This study involves the reductionist fragment-based approach to understand the structure adopted by N-terminal fragment of Alzheimer’s Aβ peptide in its complex with PLA₂. In the current communication, we report the structure determined by X-ray crystallography of N-terminal sequence Asp-Ala-Glu-Phe-Arg-His-Asp-Ser (DAEFRHDS) of Aβ-peptide with a Group I PLA₂ purified from venom of Andaman Cobra sub-species Naja naja sagittifera at 2.0 Å resolution (Protein Data Bank (PDB) Code: 3JQ5). This is probably the first attempt to structurally establish interaction between amyloid-β peptide fragment and hydrophobic substrate binding site of PLA₂ involving H bond and van der Waals interactions. We speculate that higher affinity between Aβ and PLA₂ has the therapeutic potential of decreasing the Aβ–Aβ interaction, thereby reducing the amyloid aggregation and plaque formation in AD.

Health economic evaluation of treatments for Alzheimer's disease: impact of new diagnostic criteria

The socio-economic impact of Alzheimer's disease (AD) and other dementias is enormous, and the potential economic challenges ahead are clear given the projected future numbers of individuals with these conditions. Because of the high prevalence and cost of dementia, it is very important to assess any intervention from a cost-effectiveness viewpoint. The diagnostic criteria for preclinical AD suggested by the National Institute on Aging and Alzheimer's Association workgroups in combination with the goal of effective disease-modifying treatment (DMT) are, however, a challenge for clinical practice and for the design of clinical trials. Key issues for future cost-effectiveness studies include the following: (i) the consequences for patients if diagnosis is shifted from AD-dementia to predementia states, (ii) bridging the gap between clinical trial populations and patients treated in clinical practice, (iii) translation of clinical trial end-points into measures that are meaningful to patients and policymakers/payers and (iv) how to measure long-term effects. To improve cost-effectiveness studies, long-term population-based data on disease progression, costs and outcomes in clinical practice are needed not only in dementia but also in predementia states. Reliable surrogate end-points in clinical trials that are sensitive to detect effects even in predementia states are also essential as well as robust and validated modelling methods from predementia states that also take into account comorbidities and age. Finally, the ethical consequences of early diagnosis should be considered.

Geniposide ameliorates learning memory deficits, reduces tau phosphorylation and decreases apoptosis via GSK3β pathway in streptozotocin-induced alzheimer rat model

Intracerebral-ventricular (ICV) injection of streptozotocin (STZ) induces an insulin-resistant brain state that may underlie the neural pathogenesis of sporadic Alzheimer disease (AD). Our previous work showed that prior ICV treatment of glucagon-like peptide-1 (GLP-1) could prevent STZ-induced learning memory impairment and tau hyperphosphorylation in the rat brain. The Chinese herbal medicine geniposide is known to relieve symptoms of type 2 diabetes. Because geniposide is thought to act as a GLP-1 receptor agonist, we investigated the potential therapeutic effect of geniposide on STZ-induced AD model in rats. Our result showed that a single injection of geniposide (50 μM, 10 μL) to the lateral ventricle prevented STZ-induced spatial learning deficit by about 40% and reduced tau phosphorylation by about 30% with Morris water maze test and quantitative immunohistochemical analysis, respectively. It has been known that tau protein can be phosphorylated by glycogen synthase kinase-3 (GSK3) and STZ can increase the activity of GSK3β. Our result with Western blot analysis showed that central administration of geniposide resulted in an elevated expression of GSK3β(pS-9) but suppressed GSK3β(pY-216) indicating that geniposide reduced STZ-induced GSK3β hyperactivity. In addition, ultrastructure analysis showed that geniposide averted STZ-induced neural pathology, including paired helical filament (PHF)-like structures, accumulation of vesicles in synaptic terminal, abnormalities of endoplasmic reticulum (ER) and early stage of apoptosis. In summary, our study suggests that the water soluble and orally active monomer of Chinese herbal medicine geniposide may serve as a novel therapeutic agent for the treatment of sporadic AD.

The estimation of utility weights in cost-utility analysis for mental disorders: a systematic review

OBJECTIVE

To systematically review approaches and instruments used to derive utility weights in cost-utility analyses (CUAs) within the field of mental disorders and to identify factors that may have influenced the choice of the approach.

METHODS

We searched the databases DARE (Database of Abstracts of Reviews of Effects), NHS EED (National Health Service Economic Evaluation Database), HTA (Health Technology Assessment), and PubMed for CUAs. Studies were included if they were full economic evaluations and reported quality-adjusted life-years as the health outcome. Study characteristics and instruments used to estimate utility weights were described and a logistic regression analysis was conducted to identify factors associated with the choice of either the direct (e.g. standard gamble) or the preference-based measure (PBM) approach (e.g. EQ-5D).

RESULTS

We identified 227 CUAs with a maximum in 2009, 2010, and 2012. Most CUAs were conducted in depression, dementia, or psychosis, and came from the US or the UK, with the EQ-5D being the most frequently used instrument. The application of the direct approach was significantly associated with depression, psychosis, and model-based studies. The PBM approach was more likely to be used in recent studies, dementia, Europe, and empirical studies. Utility weights used in model-based studies were derived from only a small number of studies.

LIMITATIONS

We only searched four databases and did not evaluate the quality of the included studies.

CONCLUSIONS

Direct instruments and PBMs are used to elicit utility weights in CUAs with different frequencies regarding study type, mental disorder, and country.

Challenges with cost-utility analyses of behavioural interventions among older adults at risk for dementia

BACKGROUND

Cognitive decline is one of the most prominent healthcare issues of the 21st century. Within the context of combating cognitive decline through behavioural interventions, physical activity is a promising approach. There is a dearth of health economic data in the area of behavioural interventions for dementia prevention. Yet, economic evaluations are essential for providing information to policy makers for resource allocation. It is essential we first address population and intervention-specific methodological challenges prior to building a larger evidence base. We use a cost-utility analysis conducted alongside the exercise for cognition and everyday living (EXCEL) study to illustrate methodological challenges specific to assessing the cost-effectiveness of behavioural interventions aimed at older adults at risk of cognitive decline.

METHODS

A cost-utility analysis conducted concurrently with a 6-month, three-arm randomised controlled trial (ie, the EXCEL study) was used as an example to identify and discuss methodological challenges.

RESULTS

Both the aerobic training and resistance training interventions were less costly than twice weekly balance and tone classes. In critically evaluating the economic evaluation of the EXCEL study we identified four category-specific challenges: (1) analysing costs; (2) assessing quality-adjusted life-years; (3) Incomplete data; and (4) 'Intervention' activities of the control group.

CONCLUSIONS

Resistance training and aerobic training resulted in healthcare cost saving and were equally effective to balance and tone classes after only 6 months of intervention. To ensure this population is treated fairly in terms of claims on resources, we first need to identify areas for methodological improvement.

Increased risk of dementia in patients with mild traumatic brain injury: a nationwide cohort study

Background

It is known that the risk of dementia in patients with moderate to severe traumatic brain injury (TBI) is higher. However, the relationship between mild traumatic brain injury (mTBI) and dementia has never been established.

Objectives

We investigated the incidences of dementia among patients with mTBI in Taiwan to evaluate if there is higher risk compared with general population.

Methods

We utilized a sampled National Health Insurance (NHI) claims data containing one million beneficiaries. We followed all adult beneficiaries from January 1, 2005 till December 31, 2009 to see if they had been diagnosed with dementia. We further identify patients with mTBI and compared their risk of dementia with the general population.

Results

We identified 28551 patients with mTBI and 692382 without. After controlled for age, gender, urbanization level, socioeconomic status, diabetes, hypertension, coronary artery disease, hyperlipidemia, history of alcohol intoxication, history of ischemic stroke, history of intracranial hemorrhage and Charlson Comorbidity Index Score, the adjusted hazard ratio is 3.26 (95% Confidence interval, 2.69–3.94).

Conclusions

TBI is an independent significant risk factor of developing dementia even in the mild type.