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Amat-ur-Rasool H, Ahmed M, Hasnain S, Ahmed A, Carter WG. In Silico Design of Dual-Binding Site Anti-Cholinesterase Phytochemical Heterodimers as Treatment Options for Alzheimer’s Disease. Curr Issues Mol Biol 2021; 44:152-175. [PMID: 35723391 PMCID: PMC8929005 DOI: 10.3390/cimb44010012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 12/24/2021] [Accepted: 12/27/2021] [Indexed: 12/14/2022] Open
Abstract
The number of patients with neurodegenerative diseases, particularly Alzheimer’s disease (AD), continues to grow yearly. Cholinesterase inhibitors (ChEIs) represent the first-line symptomatic drug treatment for mild-to-moderate AD; however, there is an unmet need to produce ChEIs with improved efficacy and reduced side effects. Herein, phytochemicals with reported anti-acetylcholinesterase (AChE) activity were ranked in silico for their anti-AChE potential. Ligands with a similar or higher binding affinity to AChE than galantamine were then selected for the design of novel dual-binding site heterodimeric drugs. In silico molecular docking of heterodimers with the target enzymes, AChE and butyrylcholinesterase (BuChE), were performed, and anti-cholinesterase binding affinities were compared with donepezil. Drug-likeliness properties and toxicity of the heterodimers were assessed using the SwissADME and ProTox-II webservers. Nine phytochemicals displayed similar or higher binding affinities to AChE than galantamine: sanguinarine > huperzine A > chelerythrine > yohimbine > berberine > berberastine > naringenin > akuammicine > carvone. Eleven heterodimeric ligands were designed with phytochemicals separated by four- or five-carbon alkyl-linkers. All heterodimers were theoretically potent AChE and BuChE dual-binding site inhibitors, with the highest affinity achieved with huperzine-4C-naringenin, which displayed 34% and 26% improved affinity to AChE and BuChE, respectively, then the potent ChEI drug, donepezil. Computational pharmacokinetic and pharmacodynamic screening suggested that phytochemical heterodimers would display useful gastrointestinal absorption and with relatively low predicted toxicity. Collectively, the present study suggests that phytochemicals could be garnered for the provision of novel ChEIs with enhanced drug efficacy and low toxicity.
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Affiliation(s)
- Hafsa Amat-ur-Rasool
- School of Medicine, Royal Derby Hospital Centre, University of Nottingham, Derby DE22 3DT, UK;
- Department of Microbiology and Molecular Genetics, University of the Punjab, Lahore 54590, Pakistan; (M.A.); (S.H.)
| | - Mehboob Ahmed
- Department of Microbiology and Molecular Genetics, University of the Punjab, Lahore 54590, Pakistan; (M.A.); (S.H.)
| | - Shahida Hasnain
- Department of Microbiology and Molecular Genetics, University of the Punjab, Lahore 54590, Pakistan; (M.A.); (S.H.)
| | - Abrar Ahmed
- Faculty of Pharmacy, Punjab University College of Pharmacy, University of the Punjab, Lahore 54590, Pakistan;
| | - Wayne Grant Carter
- School of Medicine, Royal Derby Hospital Centre, University of Nottingham, Derby DE22 3DT, UK;
- Correspondence: ; Tel.: +44-(0)-1332-724738
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Amat-ur-Rasool H, Ahmed M, Hasnain S, Carter WG. Anti-Cholinesterase Combination Drug Therapy as a Potential Treatment for Alzheimer's Disease. Brain Sci 2021; 11:brainsci11020184. [PMID: 33540879 PMCID: PMC7913148 DOI: 10.3390/brainsci11020184] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/27/2021] [Accepted: 01/30/2021] [Indexed: 01/29/2023] Open
Abstract
Alzheimer’s disease (AD) is a burgeoning social and healthcare problem. Cholinesterase inhibitors (ChEIs) are employed for symptomatic treatment of AD, but often elicit adverse drug reactions (ADRs). Herein, the potency of the ChEIs, donepezil, tacrine, berberine, and galantamine to inhibit human or Torpedo californica acetylcholinesterase (tcAChE) proteins were evaluated. The efficacy of dual-drug combinations to inhibit human AChE directly and within differentiated neurons was also quantified. ChEI potency was in the order: donepezil > tacrine > berberine > galantamine for both AChEs. Dual-drug combinations of berberine and tacrine (BerTac), berberine and galantamine (BerGal), and tacrine and donepezil (TacDon) all produced synergistic outcomes for AChE inhibition. Donepezil and berberine (DonBer) and tacrine and galantamine (TacGal) elicited antagonistic responses. Donepezil and galantamine (DonGal) was synergistic for human AChE but antagonistic for tcAChE. After application of dual-drug combinations to neuronal cells, BerTac, BerGal, DonGal, and DonBer all showed synergistic inhibition of AChE, TacDon additive, and TacGal antagonistic effects. BerGal produced the most potent synergism and reduced total drug dose by 72%. Individual ChEIs or dual-drug combinations were relatively non-toxic to neuronal cells, and only reduced cell viability at concentrations two–three orders of magnitude greater than that required to inhibit AChE. In summary, dual-drug combinations of ChEIs potentially represent a novel means of AD patient treatment, with reduced and more cost-effective drug dosing, and lowered likelihood of ADRs.
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Affiliation(s)
- Hafsa Amat-ur-Rasool
- Royal Derby Hospital Centre, School of Medicine, University of Nottingham, Derby DE22 3DT, UK;
- Department of Microbiology and Molecular Genetics, University of the Punjab, Lahore 54590, Pakistan; (M.A.); (S.H.)
| | - Mehboob Ahmed
- Department of Microbiology and Molecular Genetics, University of the Punjab, Lahore 54590, Pakistan; (M.A.); (S.H.)
| | - Shahida Hasnain
- Department of Microbiology and Molecular Genetics, University of the Punjab, Lahore 54590, Pakistan; (M.A.); (S.H.)
| | - Wayne G. Carter
- Royal Derby Hospital Centre, School of Medicine, University of Nottingham, Derby DE22 3DT, UK;
- Correspondence: ; Tel.: +44-(0)1332-724738
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Lin PJ, D'Cruz B, Leech AA, Neumann PJ, Sanon Aigbogun M, Oberdhan D, Lavelle TA. Family and Caregiver Spillover Effects in Cost-Utility Analyses of Alzheimer's Disease Interventions. PHARMACOECONOMICS 2019; 37:597-608. [PMID: 30903567 DOI: 10.1007/s40273-019-00788-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
BACKGROUND AND OBJECTIVE Alzheimer's disease or dementia can impose a significant burden on family and other informal caregivers. This study investigated how the inclusion of family/informal caregiver spillover effects in a cost-utility analysis may influence the reported value of Alzheimer's disease/dementia interventions. METHODS We used PubMed to identify Alzheimer's disease or dementia cost-utility analyses published from 1 January, 2000 to 31 March, 2018. We reviewed and abstracted information from each study using a two-reader consensus process. We investigated the frequency and methods in which family/caregiver spillover costs and health effects were incorporated into cost-utility analyses, and examined how their inclusion may influence the reported incremental cost-effectiveness ratios. RESULTS Of 63 Alzheimer's disease/dementia cost-utility analyses meeting inclusion criteria, 44 (70%) considered at least some family/caregiver spillover costs or health effects. Thirty-two studies incorporated spillover costs only, two incorporated spillover health effects only, and ten incorporated both. The most common approach for accounting for spillover was adding informal caregiving time costs to patient costs (n = 36) and adding informal caregiver quality-adjusted life-years to patient values (n = 7). In a subset of 33 incremental cost-effectiveness ratio pairs from 19 studies, incorporating spillover outcomes made incremental cost-effectiveness ratios more favorable (n = 15; 45%) or kept the intervention cost saving (n = 13; 39%) in most cases. In fewer cases, including spillover increased incremental cost-effectiveness ratios (n = 2; 6%), kept the intervention dominated [more costs/less quality-adjusted life-years] (n = 2; 6%), or changed incremental cost-effectiveness ratio from dominated to less cost/less quality-adjusted life-years (n = 1; 3%). In 11 cases (33%), adding spillover effects into analyses resulted in a lower incremental cost-effectiveness ratio that crossed a common cost-effectiveness threshold, which could have downstream implications for programs or policies that are adopted based on cost-effectiveness analysis results. DISCUSSION Most Alzheimer's disease/dementia cost-utility analyses incorporated spillover costs, often as caregiver time costs, but considered spillover health impacts less often. In about 85% of the analyses, including Alzheimer's disease/dementia spillover cost or health effects decreased incremental cost-effectiveness ratios or kept the intervention cost saving. The broader value of an Alzheimer's disease/dementia intervention to society may in some cases be underestimated without considering these spillover effects on family and informal caregivers.
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Affiliation(s)
- Pei-Jung Lin
- Center for the Evaluation of Value and Risk in Health, Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, 800 Washington Street, Box #63, Boston, MA, 02111, USA.
| | - Brittany D'Cruz
- Center for the Evaluation of Value and Risk in Health, Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, 800 Washington Street, Box #63, Boston, MA, 02111, USA
| | - Ashley A Leech
- Center for the Evaluation of Value and Risk in Health, Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, 800 Washington Street, Box #63, Boston, MA, 02111, USA
| | - Peter J Neumann
- Center for the Evaluation of Value and Risk in Health, Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, 800 Washington Street, Box #63, Boston, MA, 02111, USA
| | - Myrlene Sanon Aigbogun
- Health Outcomes, Otsuka Pharmaceutical Development & Commercialization, Inc., Princeton, NJ, USA
| | - Dorothee Oberdhan
- Health Outcomes, Otsuka Pharmaceutical Development & Commercialization, Inc., Princeton, NJ, USA
| | - Tara A Lavelle
- Center for the Evaluation of Value and Risk in Health, Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, 800 Washington Street, Box #63, Boston, MA, 02111, USA
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Ebrahem AS, Oremus M. A pharmacoeconomic evaluation of cholinesterase inhibitors and memantine for the treatment of Alzheimer's disease. Expert Opin Pharmacother 2018; 19:1245-1259. [PMID: 29999427 DOI: 10.1080/14656566.2018.1499727] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
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.
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Affiliation(s)
- Anees Shajhan Ebrahem
- a School of Public Health and Health Systems , University of Waterloo , Waterloo , Ontario , Canada
| | - Mark Oremus
- a School of Public Health and Health Systems , University of Waterloo , Waterloo , Ontario , Canada
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Lenox-Smith A, Reed C, Lebrec J, Belger M, Jones RW. Potential cost savings to be made by slowing cognitive decline in mild Alzheimer's disease dementia using a model derived from the UK GERAS observational study. BMC Geriatr 2018; 18:57. [PMID: 29471784 PMCID: PMC5824582 DOI: 10.1186/s12877-018-0748-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 02/15/2018] [Indexed: 11/16/2022] Open
Abstract
Background Given the high costs associated with the care of those with Alzheimer’s disease (AD) dementia, we examined the likely impact of a reduction in the rate of cognitive decline upon cost outcomes associated with this disease. Methods Using the group of patients with mild AD dementia from the GERAS study, generalised linear modelling (GLM) was used to explore the relationship between change in cognition as measured using the Mini-Mental State Examination (MMSE) and UK overall costs (health care and social care costs, and total societal costs) associated with AD dementia. Results A total of 200 patients with mild AD dementia were identified. Least squares mean (LSM) ± standard error (SE) reduction in MMSE score was 3.6 ± 0.4 points over 18 months. Using GLM it was possible to calculate that this worsening in cognition was associated with an 8.7% increase in total societal costs, equating to an increase of approximately £2200 per patient over an 18-month period. If the rate of decline in cognition was reduced by 30% or 50%, the associated savings in total societal costs over 18 months would be approximately £670 and £1100, respectively, of which only £110 and £180, respectively, could be attributed to a saving of health care costs. Conclusion This study demonstrates that there are potential savings to be made in the care of patients with AD dementia through reducing the rate of cognitive decline. A reduction in wider societal costs is likely to be the main contributor to these potential savings, and need to be further evaluated when intervention costs and cost offsets can be measured.
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Affiliation(s)
- Alan Lenox-Smith
- Eli Lilly and Company, Priestly Road, Basingstoke, RG24 9NL, UK.
| | | | | | - Mark Belger
- Eli Lilly and Company, Erl Wood, Windlesham, UK
| | - Roy W Jones
- RICE (The Research Institute for the Care of Older People), Royal United Hospital, Bath, UK
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Zala D, Chan D, McCrone P. The cost-effectiveness implications of suboptimal treatment for different severities of Alzheimer's disease in the UK. Int J Geriatr Psychiatry 2018; 33:307-315. [PMID: 28612928 DOI: 10.1002/gps.4745] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 04/19/2017] [Indexed: 11/11/2022]
Abstract
OBJECTIVE This study aims to evaluate the impact of suboptimal treatment, defined in terms of lower population coverage (percentage of total patient population receiving optimal treatment) and delay to treatment on the cost-effectiveness of pharmacological therapies approved for the treatment of different severities of Alzheimer's disease (AD) in the UK. METHODS A 5-year Markov model was used to simulate transition to full-time care, as delay and coverage were varied for AD patients with mild-to-moderate and moderate-to-severe dementia. The time-varying predictive equations, resource use, utilities, treatment effects and mortality were derived using published sources. RESULTS For the cohort with moderate-to-severe dementia, cost-effectiveness was optimised when delay was minimised and coverage maximised. For mild-to-moderate dementia, results were similar but varied widely depending on the inputted cost of acetylcholinesterase inhibitors. CONCLUSIONS The average cost-effectiveness of pharmacological treatments for AD is sensitive to delays to treatment and population coverage. The results of this study can inform future healthcare policy in order to maximise cost-effectiveness of pharmacological therapies for AD. Copyright © 2017 John Wiley & Sons, Ltd.
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Affiliation(s)
- Darshan Zala
- Department of Health Service and Population Research, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Dennis Chan
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Paul McCrone
- Department of Health Service and Population Research, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
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Nguyen KH, Sellars M, Agar M, Kurrle S, Kelly A, Comans T. An economic model of advance care planning in Australia: a cost-effective way to respect patient choice. BMC Health Serv Res 2017; 17:797. [PMID: 29191183 PMCID: PMC5709848 DOI: 10.1186/s12913-017-2748-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2017] [Accepted: 11/20/2017] [Indexed: 11/10/2022] Open
Abstract
Background Advance care planning (ACP) is a process of planning for future health and personal care. A person’s values and preferences are made known so that they can guide decision making at a future time when that person cannot make or communicate his or her decisions. This is particularly relevant for people with dementia because their ability to make decisions progressively deteriorates over time. This study aims to evaluate the cost-effectiveness of delivering a nationwide ACP program within the Australian primary care setting. Methods A decision analytic model was developed to identify the costs and outcomes of an ACP program for people aged 65+ years who were at risk of developing dementia. Inputs for the model was sourced and estimated from the literature. The reliability of the results was thoroughly tested in sensitivity analyses. Results The results showed that, compared to usual care, a nationwide ACP program for people aged 65+ years who were at risk of dementia would be cost-effective. However, the results only hold if ACP completion is higher than 50% and adherence to ACP wishes is above 75%. Conclusions A nationwide ACP program in the primary care setting is a cost-effective or cost-saving intervention compared to usual care in a population at-risk of developing dementia. Cost savings are generated from providing treatment and care that is consistent with patient preferences, resulting in fewer hospitalisations and less-intensive care at end-of-life. Electronic supplementary material The online version of this article (10.1186/s12913-017-2748-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Kim-Huong Nguyen
- Center for Applied Health Economics, Griffith University, Brisbane, Queensland, Australia. .,NHMRC Cognitive Decline Partnership Centre, the University of Sydney, Sydney, New South Wales, Australia. .,Metro North Hospital and Health Service District, Brisbane, Queensland, Australia.
| | - Marcus Sellars
- Advance Care Planning Australia, Austin Health, Melbourne, Victoria, Australia.,Kolling Institute, Northern Clinical School, Faculty of Medicine, The University of Sydney, Sydney, New South Wales, Australia
| | - Meera Agar
- NHMRC Cognitive Decline Partnership Centre, the University of Sydney, Sydney, New South Wales, Australia.,University of Technology Sydney, Sydney, New South Wales, Australia.,University of New South Wales, Sydney, Australia.,Ingham Institute of Applied Medical Research, Sydney, New South Wales, Australia.,South West Sydney Local Health District, Sydney, New South Wales, Australia
| | - Sue Kurrle
- NHMRC Cognitive Decline Partnership Centre, the University of Sydney, Sydney, New South Wales, Australia.,Northern Clinical School, University of Sydney, Sydney, New South Wales, Australia
| | - Adele Kelly
- NHMRC Cognitive Decline Partnership Centre, the University of Sydney, Sydney, New South Wales, Australia.,HammondCare, Sydney, New South Wales, Australia
| | - Tracy Comans
- NHMRC Cognitive Decline Partnership Centre, the University of Sydney, Sydney, New South Wales, Australia.,Center for Health Service Research, Faculty of Medicine, The University of Queensland, Brisbane, Queensland, Australia.,Metro North Hospital and Health Service District, Brisbane, Queensland, Australia
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Dependence Stage and Pharmacoeconomic Outcomes in Patients With Alzheimer Disease. Alzheimer Dis Assoc Disord 2017; 31:209-217. [PMID: 28486240 DOI: 10.1097/wad.0000000000000198] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The level of assistance patients with Alzheimer disease (AD) require in their care may be an important predictor of resource use, costs of care, and quality of life. The Dependence Scale (DS), a measure of care-assistance required, was used to estimate costs of care and quality of life of patients with AD categorized into 6 dependence stages based upon the summated item scores of the DS. Data were derived from a 3-year, noninterventional study of 132 patients with probable AD (ages, 50 to 85 y) and caregiver dyads. We investigated the association between DS scores and health care costs, health-related quality of life (HRQoL), caregiver burden and estimated annual costs and HRQoL for 6 dependence stages in adjusted models. DS scores were significant predictors of health care costs, HRQoL, and caregiver burden. The estimated annual health care costs and a measure of HRQoL (EuroQoL-5D) ranged from $11,418 and 1.00 for those at very mild dependence stage to $101,715 and 0.26 for those at very severe dependence stage. DS scores classified into 6 dependence stages provides a useful method to estimate unique levels of care-associated costs and health utilities for pharmacoeconomic evaluations of new treatments for AD.
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Hernandez L, Ozen A, DosSantos R, Getsios D. Systematic Review of Model-Based Economic Evaluations of Treatments for Alzheimer's Disease. PHARMACOECONOMICS 2016; 34:681-707. [PMID: 26899832 DOI: 10.1007/s40273-016-0392-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
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.
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Affiliation(s)
- Luis Hernandez
- Evidera, 430 Bedford St #300, Lexington, MA, 02420, USA.
| | | | | | - Denis Getsios
- Evidera, 430 Bedford St #300, Lexington, MA, 02420, USA
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Sonntag M, König HH, Konnopka A. The estimation of utility weights in cost-utility analysis for mental disorders: a systematic review. PHARMACOECONOMICS 2013; 31:1131-54. [PMID: 24293216 DOI: 10.1007/s40273-013-0107-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
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.
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Affiliation(s)
- Michael Sonntag
- Department of Health Economics and Health Services Research, Hamburg Center for Health Economics, University Medical Center Hamburg-Eppendorf, Martinistr. 52, 20246, Hamburg, Germany,
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EVOLUTION OF A COST-UTILITY MODEL OF DONEPEZIL FOR ALZHEIMER'S DISEASE. Int J Technol Assess Health Care 2013; 29:147-54. [DOI: 10.1017/s026646231300007x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Objectives: The aim of this study was to describe the evolution of a cost-utility model used to inform the UK National Institute for Health and Clinical Excellence's (NICE) most recent decisions on the cost-utility of drug treatments for Alzheimer's disease (AD), and to explore the impact of structural assumptions on the cost-utility results.Methods: Changes informed by noted limitations of the decision model used in NICE's previous decisions (in 2006) were made cumulatively to the original decision model for donepezil compared with best supportive care (for patients with mild to moderate AD). Deterministic and probabilistic analyses were undertaken for each cumulative change of the model. The expected value of perfect information (EVPI) of parameter estimates and structural assumptions was also calculated.Results: Cumulative changes to the decision model highlighted how the results of the original model (incremental cost-effectiveness ratio of £81,000 per quality-adjusted life-year gained) related to those of the new model (where donepezil was estimated to be cost-saving), mainly due to uncertainty in the incremental cost of donepezil treatment over best supportive care (ranging from -£600 to £3,000 per patient). The partial EVPI analysis reflected this finding where further information on treatment discontinuations and cost parameter estimates were shown to be valuable in terms of reducing decision uncertainty.Conclusions: Assessing the evolution of the cost-utility model helped to identify and explore structural differences between cohort-based models and is likely to be useful for decision models in other disease areas. This approach makes the structural uncertainty explicit, forcing decision makers to address structural uncertainty in addition to parameter uncertainty.
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Oremus M. Systematic review of economic evaluations of Alzheimer's disease medications. Expert Rev Pharmacoecon Outcomes Res 2012; 8:273-89. [PMID: 20528379 DOI: 10.1586/14737167.8.3.273] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
This systematic review was conducted to summarize published pharmacoeconomic studies of Alzheimer's disease (AD) medications. Pharmacoeconomic studies were included in the review if they were published in English and contained a full and complete report of an original economic evaluation. The studies also had to be comparative in nature (i.e., cost-benefit, cost-effectiveness, cost-utility or cost-minimization analyses). Existing AD medications were found to dominate standard treatment (i.e., no drugs), or they were found to be more costly and more effective than standard treatment. Estimates of cost and effect varied widely because of different underlying models, assumptions and data sources. More research is needed to draw firmer conclusions regarding the overall cost-effectiveness of AD medications.
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Affiliation(s)
- Mark Oremus
- McMaster Evidence-based Practice Centre; Assistant Professor (Part-Time), Department of Clinical Epidemiology and Biostatistics; McMaster Evidence-based Practice Centre, McMaster University, 50 Main Street East, Hamilton, Ontario, L8N 1E9, Canada.
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Shearer J, Green C, Ritchie CW, Zajicek JP. Health state values for use in the economic evaluation of treatments for Alzheimer's disease. Drugs Aging 2012; 29:31-43. [PMID: 22191721 DOI: 10.2165/11597380-000000000-00000] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Alzheimer's disease (AD) is a chronic, progressive, neurodegenerative disease that places a heavy burden on people with the condition, their families and carers, health care systems and society in general. Health-related quality of life (HR-QOL) in patients deteriorates as the cognitive, behavioural and functional symptoms of AD develop. The human and financial cost of AD is forecast to grow rapidly as populations age, and those responsible for planning and financing health care face the challenge of allocating increasingly scarce resources against current and future interventions targeted towards AD. These include calls for early detection and diagnosis, preventative strategies, new medications, residential care, supportive care, and meeting the needs of carers as well as patients. Health care funders in many health systems now require a demonstration of the value of new interventions through a comparison of benefits in terms of improvements in HR-QOL and costs relative to those of competing or existing practices. Changes in HR-QOL provide the basis for the calculation of the quality-adjusted life-year (QALY), a key outcome used in economic evaluations to compare treatments within and between different disease conditions. The objective of this systematic review was to provide a summary of the published health state values (utilities) for AD patients and their carers that are currently available to estimate QALYs for use in health economic evaluations of interventions in AD. The health care literature was searched for articles published in English between 2000 and 2011, using keywords and variants including 'quality-adjusted life years', 'health state indicators', 'health utilities' and the specific names of generic measures of HR-QOL and health state valuation techniques. Databases searched included MEDLINE, EMBASE, NHS EED, PsycINFO and ISI Web of Science. This review identified 12 studies that reported utility values associated with health states in AD. Values for AD health states categorized according to cognitive impairment (where 1 = perfect health and 0 = dead) ranged from mild AD (0.52-0.73) to moderate AD (0.30-0.53) to severe AD (0.12-0.49). Utility values were almost all based on two generic measures of HR-QOL: the EQ-5D and Health Utility Index mark 2/3 (HUI2/3). There were no health state values estimated from condition- or disease-specific measures of HR-QOL. The review also identified 18 published cost-utility analyses (CUAs) of treatments for AD. The CUAs incorporated results from only three of the identified health state valuation studies. Twelve CUAs relied on the same study for health state values. We conclude that the literature on health state values in AD is limited and overly reliant on a single symptom (cognition) to describe disease progression. Other approaches to characterizing disease progression in AD based on multiple outcomes or dependency may be better predictors of costs and utilities in economic evaluations. Patient and proxy ratings were poorly correlated, particularly in patients with more advanced AD. However, proxy ratings displayed the validity and reliability across the entire range of AD severity needed to detect long-term changes relevant to economic evaluation. Further longitudinal research of patient and carer HR-QOL based on multidimensional measures of outcome and utilities is needed.
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Affiliation(s)
- James Shearer
- Health Economics Group, Institute of Health Service Research, Peninsula College of Medicine and Dentistry, University of Exeter, Exeter, UK.
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Pouryamout L, Dams J, Wasem J, Dodel R, Neumann A. Economic evaluation of treatment options in patients with Alzheimer's disease: a systematic review of cost-effectiveness analyses. Drugs 2012; 72:789-802. [PMID: 22480339 DOI: 10.2165/11631830-000000000-00000] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
INTRODUCTION Alzheimer's disease (AD) is common among the elderly; it is responsible for 60-80% of all dementia cases. AD is characterized by cognitive decline, behavioural and psychological symptoms, and reductions in functioning and independence. Because of its progressive neurodegenerative nature and unknown aetiology, the burden of AD becomes increasingly significant in an aging population. Estimates indicate that 35.6 million people worldwide suffered from AD in 2010. By 2030 and 2050, this figure is predicted to increase to 65.7 million and 115.4 million, respectively. Costs will also rise along with the increase in the number of people diagnosed with AD. In 2010, the worldwide costs associated with dementia were estimated to be $US604 billion. OBJECTIVE The objective of this study was to conduct a systematic review of current publications dealing with the pharmacoeconomic factors associated with AD medications and to describe the decision-analytic models used to evaluate long-term outcomes. METHODS A systematic literature search was performed to identify articles published between 1 January 2007 and 15 July 2010. The search was also based on a previous systematic review, which included literature up to 2007. Articles were included if they were complete and original economic evaluations of AD and if they were comparative in nature. A quality assessment of the included publications was conducted and relevant information was extracted into tables. RESULTS Seven out of 2067 identified articles were included in this systematic review. Four articles evaluated treatment with donepezil, one with galantamine and two with memantine. The studies were conducted in America, Europe and Asia. Five different groups of medications were compared. The incremental cost-effectiveness ratios (ICERs) for the group of patients treated with donepezil versus no drug treatment ranged from a dominant value to 281, 416.13 euros per quality-adjusted life-year (QALY). Patients treated with donepezil versus placebo showed ICERs with a range from a dominant value (not specified) up to 20, 866.77 euros per QALY. Treatment with memantine in addition to donepezil versus treatment with donepezil alone showed an ICER range from a dominant value to 6818.33 euros per QALY. In comparison with the memantine treatment as an add-on therapy, the ICER of memantine monotherapy versus standard care (without cholinesterase inhibitors [CEIs]) ranged from a dominant value to 63, 087.20 euros per QALY. Finally, the economic evaluation of galantamine in comparison with usual care without any AD drugs showed ICERs ranging from 1894.70 euros to 6953 euros per QALY. CONCLUSION The seven identified publications included in this review indicate that treatment with CEIs or memantine seems to be reasonable in terms of clinical effects and costs for patients with AD. Depending on different hypotheses, assumptions and variables (e.g. time horizon, discount rates, initial number of patients in different states, etc.) in the sensitivity analyses, treatment with these drugs seems to be primarily a cost-effective strategy or even a cost-saving strategy. Nevertheless, the results generally are associated with a degree of uncertainty. The comparability of the results from the different economic evaluations is limited because of the different assumptions made.
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Affiliation(s)
- Laura Pouryamout
- Institute of Health Care Management and Research, University of Duisburg-Essen, Essen, Germany
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15
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Versijpt J. Pharmacoeconomics of Alzheimer's disease (AD) treatment with cholinesterase inhibitors. Acta Neurol Belg 2012; 112:141-5. [PMID: 22476975 DOI: 10.1007/s13760-012-0062-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Accepted: 03/13/2012] [Indexed: 10/28/2022]
Abstract
Until more effective and especially disease-modifying treatments for Alzheimer's disease (AD) are available, the therapeutic arsenal consists of cholinesterase inhibitors for mild to moderate dementia and memantine for moderate to severe dementia. Health economic data make an important contribution to the planning of healthcare services and the estimation of the cost of drug reimbursement. As such, for cholinesterase inhibitors it is claimed that the direct cost of the drug itself is eclipsed by the cost savings associated with delaying institutionalisation or delaying the time of progression into a more severe disease state. The present manuscript reviews several factors contributing to the costs of AD, gives an overview of available studies claiming the cost-effectiveness of current AD treatments, highlights strengths and weaknesses of the aforementioned studies, and discusses the impact of (early) identification and treatment of AD. It is concluded that there still is a need for long-term follow-up data from prospective cohort studies before the cost-effectiveness of cholinesterase inhibitors for AD can be confirmed.
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Rive B, Aarsland D, Grishchenko M, Cochran J, Lamure M, Toumi M. Cost-effectiveness of memantine in moderate and severe Alzheimer's disease in Norway. Int J Geriatr Psychiatry 2012; 27:573-82. [PMID: 21834130 DOI: 10.1002/gps.2755] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2010] [Accepted: 05/09/2011] [Indexed: 11/11/2022]
Abstract
BACKGROUND The cost-effectiveness of memantine for the treatment of moderate and severe Alzheimer's disease has been assessed in several European countries. Objective of the study was to assess it in Norwegian settings. METHODS This cost-utility analysis used a Markov modelling approach to simulate the evolution of patients until their need for full-time care (FTC) over a 5-year period. FTC was defined as a patient becoming either dependent or institutionalised. Transition probabilities were estimated using a newly developed predictive equation of time to FTC. Health resource use and utilities were obtained from the Scandinavian Study of Cost and Quality of Life in Alzheimer's Disease study, and mortality was obtained from the Oslo study. Memantine efficacy was based on a meta-analysis of six large trials. The model compared memantine with its alternative in this population, that is no pharmacological treatment or background therapy with acetylcholinesterase inhibitors. The model underwent extensive sensitivity analyses. RESULTS In Norway, memantine was found to delay the need for FTC by 4.4 weeks compared with standard care and was associated with increased quality-adjusted life years. Memantine was the dominant strategy with cost savings of €3739 (30 041 NOK) per patient. The probability of being the dominant strategy was 98.8%. This result was confirmed across multiple sensitivity analyses. CONCLUSIONS The model suggests that memantine prolongs time to FTC for no additional cost to the healthcare system and society. It can be regarded as a cost-effective choice in the management of moderate and severe Alzheimer's disease.
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Affiliation(s)
- B Rive
- University of Lyon I, Lyon, France.
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Hartz S, Getsios D, Tao S, Blume S, Maclaine G. Evaluating the cost effectiveness of donepezil in the treatment of Alzheimer's disease in Germany using discrete event simulation. BMC Neurol 2012; 12:2. [PMID: 22316501 PMCID: PMC3296601 DOI: 10.1186/1471-2377-12-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Accepted: 02/08/2012] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Previous cost-effectiveness studies of cholinesterase inhibitors have modeled Alzheimer's disease (AD) progression and treatment effects through single or global severity measures, or progression to "Full Time Care". This analysis evaluates the cost-effectiveness of donepezil versus memantine or no treatment in Germany by considering correlated changes in cognition, behavior and function. METHODS Rates of change were modeled using trial and registry-based patient level data. A discrete event simulation projected outcomes for three identical patient groups: donepezil 10 mg, memantine 20 mg and no therapy. Patient mix, mortality and costs were developed using Germany-specific sources. RESULTS Treatment of patients with mild to moderately severe AD with donepezil compared to no treatment was associated with 0.13 QALYs gained per patient, and 0.01 QALYs gained per caregiver and resulted in average savings of €7,007 and €9,893 per patient from the healthcare system and societal perspectives, respectively. In patients with moderate to moderately-severe AD, donepezil compared to memantine resulted in QALY gains averaging 0.01 per patient, and savings averaging €1,960 and €2,825 from the healthcare system and societal perspective, respectively.In probabilistic sensitivity analyses, donepezil dominated no treatment in most replications and memantine in over 70% of the replications. Donepezil leads to savings in 95% of replications versus memantine. CONCLUSIONS Donepezil is highly cost-effective in patients with AD in Germany, leading to improvements in health outcomes and substantial savings compared to no treatment. This holds across a variety of sensitivity analyses.
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Affiliation(s)
- Susanne Hartz
- B214 Baquba Building, Conington Road, SE13 7FF London, UK
| | - Denis Getsios
- United BioSource Corporation, 430 Bedford Street, Suite 300, Lexington Office Park, Lexington, MA 02420, USA
| | - Sunning Tao
- United BioSource Corporation, 185 Dorval Avenue Suite 500, Dorval, Quebec H9S 5J9, Canada
| | - Steve Blume
- United BioSource Corporation, 7101 Wisconsin Avenue, Bethesda, MD 20814, USA
| | - Grant Maclaine
- Becton, Dickinson UK Limited, The Danby Building, Edmund Halley Road, Oxford Science Park, Oxford OX4 4DQ, UK
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18
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Dependence as a unifying construct in defining Alzheimer's disease severity. Alzheimers Dement 2011; 6:482-93. [PMID: 21044778 DOI: 10.1016/j.jalz.2009.09.004] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2009] [Revised: 07/24/2009] [Accepted: 09/08/2009] [Indexed: 01/13/2023]
Abstract
This article reviews measures of Alzheimer's disease (AD) progression in relation to patient dependence and offers a unifying conceptual framework for dependence in AD. Clinicians typically characterize AD by symptomatic impairments in three domains: cognition, function, and behavior. From a patient's perspective, changes in these domains, individually and in concert, ultimately lead to increased dependence and loss of autonomy. Examples of dependence in AD range from a need for reminders (early AD) to requiring safety supervision and assistance with basic functions (late AD). Published literature has focused on the clinical domains as somewhat separate constructs and has given limited attention to the concept of patient dependence as a descriptor of AD progression. This article presents the concept of dependence on others for care needs as a potential method for translating the effect of changes in cognition, function, and behavior into a more holistic, transparent description of AD progression.
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Simoens S. Public health and prevention in Europe: is it cost-effective? JOURNAL OF PHARMACEUTICAL HEALTH SERVICES RESEARCH 2011. [DOI: 10.1111/j.1759-8893.2011.00052.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Abstract
Objectives
In the public debate surrounding public health and prevention, it is sometimes assumed that preventive interventions are by definition cost-effective. This paper aims to explore whether preventive pharmaceutical interventions are more cost-effective than a curative approach to diseases.
Methods
A descriptive study identified European economic evaluations in the Tufts Medical Center Cost-Effectiveness Analysis Registry between 2000 and 2007. Data were extracted on publication year, target population, intervention, patient sample, disease, prevention stage and incremental cost-utility ratio of each economic evaluation. Preventive interventions were defined as measures preventing disease onset. Curative interventions related to measures identifying patients with risk factors or preclinical disease or interventions limiting disability after harm has occurred. Results were expressed in terms of costs (valued in Euros at 2008 prices) per quality-adjusted life year. The association between incremental cost-utility ratios and prevention stage was examined by means of the Mann–Whitney U test.
Key findings
The analysis included 231 studies that reported information about 608 incremental cost-effectiveness ratios. Preventive interventions included interventions that were more effective and less expensive than comparators (41% of incremental cost-effectiveness ratios), and interventions that improved outcomes and increased costs (59%). Both preventive and curative interventions covered the full range of cost-effectiveness results. However, preventive interventions had a significantly lower median ratio of €6255 per quality-adjusted life year and were thus more cost-effective than curative interventions (€12 917 per quality-adjusted life year) (P=0.002).
Conclusions
Although the cost-effectiveness of preventive interventions varies substantially, preventive interventions tended to be more cost-effective than curative interventions.
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Affiliation(s)
- Steven Simoens
- Research Centre for Pharmaceutical Care and Pharmaco-economics, Katholieke Universiteit Leuven, Leuven, Belgium
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20
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Green C, Shearer J, Ritchie CW, Zajicek JP. Model-based economic evaluation in Alzheimer's disease: a review of the methods available to model Alzheimer's disease progression. VALUE IN HEALTH : THE JOURNAL OF THE INTERNATIONAL SOCIETY FOR PHARMACOECONOMICS AND OUTCOMES RESEARCH 2011; 14:621-30. [PMID: 21839398 DOI: 10.1016/j.jval.2010.12.008] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2010] [Revised: 11/25/2010] [Accepted: 12/22/2010] [Indexed: 05/04/2023]
Abstract
OBJECTIVE To consider the methods available to model Alzheimer's disease (AD) progression over time to inform on the structure and development of model-based evaluations, and the future direction of modelling methods in AD. METHODS A systematic search of the health care literature was undertaken to identify methods to model disease progression in AD. Modelling methods are presented in a descriptive review. RESULTS The literature search identified 42 studies presenting methods or applications of methods to model AD progression over time. The review identified 10 general modelling frameworks available to empirically model the progression of AD as part of a model-based evaluation. Seven of these general models are statistical models predicting progression of AD using a measure of cognitive function. The main concerns with models are on model structure, around the limited characterization of disease progression, and on the use of a limited number of health states to capture events related to disease progression over time. None of the available models have been able to present a comprehensive model of the natural history of AD. CONCLUSIONS Although helpful, there are serious limitations in the methods available to model progression of AD over time. Advances are needed to better model the progression of AD and the effects of the disease on peoples' lives. Recent evidence supports the need for a multivariable approach to the modelling of AD progression, and indicates that a latent variable analytic approach to characterising AD progression is a promising avenue for advances in the statistical development of modelling methods.
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Affiliation(s)
- Colin Green
- Health Economics Group, Peninsula College of Medicine and Dentistry, University of Exeter, Exeter, UK.
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21
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Johnstone TB, Gu Z, Yoshimura RF, Villegier AS, Hogenkamp DJ, Whittemore ER, Huang JC, Tran MB, Belluzzi JD, Yakel JL, Gee KW. Allosteric modulation of related ligand-gated ion channels synergistically induces long-term potentiation in the hippocampus and enhances cognition. J Pharmacol Exp Ther 2010; 336:908-15. [PMID: 21159751 DOI: 10.1124/jpet.110.176255] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
α5 Subunit-containing GABA(A) receptors (GABA(A)Rs) and α7 neuronal nicotinic-acetylcholine receptors (nAChRs) are members of the Cys-loop family of ligand-gated ion channels (LGICs) that mediate cognitive and attentional processes in the hippocampus. α5 GABA(A)Rs alter network activity by tonic inhibition of CA1/CA3 pyramidal cells of the hippocampus. Postsynaptic α7 nAChRs in the hippocampus regulate inhibitory GABAergic interneuron activity required for synchronization of pyramidal neurons in the CA1, whereas presynaptic α7 nAChRs regulate glutamate release. Can simultaneous allosteric modulation of these LGICs produce synergistic effects on cognition? We show that combined transient application of two allosteric modulators that individually 1) inhibit α5 GABA(A)Rs and 2) enhance α7 nAChRs causes long-term potentiation (LTP) of mossy fiber stimulation-induced excitatory postsynaptic currents (EPSC) from CA1 pyramidal neurons of rat hippocampal slices. The LTP effect evoked by two compounds is replicated by 3-(2,5-difluorophenyl)-6-(N-ethylindol-5-yl)-1,2,4-triazolo[4,3-b]pyridazine (522-054), a compound we designed to simultaneously inhibit α5 GABA(A)Rs and enhance α7 nAChRs. Selective antagonists for either receptor block sustained EPSC potentiation produced by 522-054. In vivo, 522-054 enhances performance in the radial arm maze and facilitates attentional states in the five-choice serial reaction time trial with similar receptor antagonist sensitivity. These observations may translate into therapeutic utility of dual action compounds in diseases of hippocampal-based cognitive impairment.
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Affiliation(s)
- Timothy B Johnstone
- Department of Pharmacology, School of Medicine, University of California, Irvine, California, USA.
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Mauskopf J, Racketa J, Sherrill E. Alzheimer's disease: the strength of association of costs with different measures of disease severity. J Nutr Health Aging 2010; 14:655-63. [PMID: 20922342 DOI: 10.1007/s12603-010-0312-6] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
OBJECTIVE To identify Alzheimer's disease (AD) severity measures for use in cost-effectiveness models that effectively capture the impact of AD on costs. METHODS A review of the literature and data abstraction from papers that present 1) mean AD costs (direct, indirect, or total) by disease severity, defined using measure of cognition, functional status, and behavior; and/or 2) the results of regression analyses that estimate the strength of the association between AD costs and disease severity. RESULTS All papers reviewed showed that mean total costs increase with disease severity regardless of severity-measurement method. The relative difference in mean total costs between patients with severe disease compared to those with moderate disease, or moderate disease compared to mild disease, was fairly consistent across studies, suggesting that any of the disease-severity measures may be used to broadly categorize patients by cost. However, when regression analysis included multiple disease-severity measures, independent associations with costs were noted for the different measures. Cognitive and functional status measures were consistently associated with direct costs, whereas functional status and behavioral measures were consistently associated with indirect costs and caregiver hours. CONCLUSIONS Either multidimensional disease-severity measures, or a single disease-severity measure, that capture the impact of cognition, functional status, and behavior on costs are needed for cost-effectiveness models.
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Affiliation(s)
- J Mauskopf
- RTI Health Solutions, 200 Park Offices Drive, Research Triangle Park, NC 27709, USA.
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McNamee P, Vanoli A, Hutchings D, McKeith I, Bond J. Savings from sub-groups?: Policy guidance and Alzheimer's disease treatments. J Nutr Health Aging 2010; 14:664-8. [PMID: 20922343 DOI: 10.1007/s12603-010-0313-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND A range of new therapeutic agents are now available for the management of Alzheimer's disease. With limited resources available however, policy-makers and other health care professionals have to prioritise and judge competing treatments on criteria such as the magnitude of clinical effectiveness and cost-effectiveness. Policy guidance that restricts treatments to defined patient sub-groups can improve the cost-effectiveness of treatments, and can help limit rises in health care expenditures. Budget impact models that estimate the amount of additional costs and potential savings are being increasingly used by policy-makers. However, the amount of savings estimated in such models depends on the effectiveness of treatment in changing morbidity, and the association between morbidity and costs. AIM To examine the magnitude of cost savings arising from provision of treatment to different patient sub-groups, using policy guidance decisions made by the National Institute for Health and Clinical Excellence (NICE) for cholinesterase inhibitor therapies in Alzheimer's Disease (AD) in the United Kingdom National Health Service (NHS). METHOD Cohort simulation modelling. RESULTS Policy guidance decisions that restricted treatment to smaller patient sub-groups were associated with lower overall care costs, but did not reduce drug costs. CONCLUSIONS Given increasing recognition by health policy-makers of the importance of affordability of new treatments, greater attention should be paid to measurement of cost impacts by sub-groups within health economic modelling.
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Affiliation(s)
- P McNamee
- Health Economics Research Unit, Institute of Applied Health Sciences, University of Aberdeen, Scotland AB25 2ZD, United Kingdom.
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Rive B, Grishchenko M, Guilhaume-Goulant C, Katona C, Livingston G, Lamure M, Toumi M, François C. Cost effectiveness of memantine in Alzheimer's disease in the UK. J Med Econ 2010; 13:371-80. [PMID: 20504112 DOI: 10.3111/13696998.2010.491347] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE This analysis assesses the cost-effectiveness of memantine for the treatment of moderate-to-severe Alzheimer's disease (AD) in the UK. METHODS This cost-utility analysis was based on a Markov model. The model simulated 5-year progress of patients with AD until they need full-time care (FTC), defined as a patient becoming either dependent or institutionalised. Transition probabilities were based on a predictive equation, derived from the London and South-East Region epidemiological study. Resource use, utilities and mortality were obtained from the same study. Memantine efficacy was based on a meta-analysis of six large trials. The model compared memantine to its alternative in the UK, i.e. no pharmacological treatment or background therapy with acetylcholinesterase inhibitors. RESULTS Memantine was found to delay the need to FTC by 6 weeks compared with current practice in the UK. It was associated with increased quality-adjusted life-years and cost savings to the healthcare system (probability of this outcome was 96%). The projections were made assuming that benefits from the 6-month treatment were sustained over time, which is regarded as the main limitation. The model underwent extensive sensitivity analyses, which confirmed the base-case findings. CONCLUSIONS The model suggests that memantine delays the need for FTC and decreases cost. It can be regarded as a cost-effective choice in the management of moderate and severe AD.
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Affiliation(s)
- B Rive
- Université Claude Bernard Lyon 1, France
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25
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Suh GH. Modeling the cost-effectiveness of galantamine for mild to moderately severe Alzheimer's disease in Korea. VALUE IN HEALTH : THE JOURNAL OF THE INTERNATIONAL SOCIETY FOR PHARMACOECONOMICS AND OUTCOMES RESEARCH 2009; 12 Suppl 3:S49-S54. [PMID: 20586982 DOI: 10.1111/j.1524-4733.2009.00627.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
OBJECTIVE The aim of the study was to determine the cost-effectiveness, from the third-party payer viewpoint, of galantamine compared with usual care in the treatment of mild to moderately severe Alzheimer's disease (AD). METHODS An existing Markov model was adapted to Korea to predict long-term outcomes over a 5-year time horizon and to estimate the cost-effectiveness of galantamine for the treatment of AD. The model structure is informed by a review of national and international literature on the clinical and cost-effectiveness of galantamine and on the costs and outcomes associated with treatment for AD. The main outcome measure used was the cost per quality-adjusted life year (QALY) gained. All costs were indexed to US$ (2007 value). Multivariate probabilistic sensitivity analysis and scenario analysis were undertaken to assess uncertainty in the results. RESULTS The study findings indicate that the clinical benefits on AD progression from galantamine treatment resulted in an incremental cost per QALY gained of US$4939 over 5 years (vs. usual care). Probabilistic sensitivity analysis and cost-effectiveness acceptability curve suggest that the probability of galantamine treatment having an incremental cost per QALY over US$6740 is zero. Incremental cost per QALY gained according to scenario analyses ranged from US$2271 to US$8335. CONCLUSION These findings suggest that the use of galantamine may be a cost-effective use of Korean national health-care resources, considering the gross domestic product per capita of US$21,695 in 2007.
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Affiliation(s)
- Guk-Hee Suh
- Department of Psychiatry, Hallym University College of Medicine, Seoul, Korea.
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Hsiung GYR, Feldman HH. Pharmacological treatment in moderate-to-severe Alzheimer's disease. Expert Opin Pharmacother 2008; 9:2575-82. [DOI: 10.1517/14656566.9.15.2575] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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27
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Cohen JT, Neumann PJ. Decision analytic models for Alzheimer's disease: state of the art and future directions. Alzheimers Dement 2008; 4:212-22. [PMID: 18631970 DOI: 10.1016/j.jalz.2008.02.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2007] [Revised: 02/01/2008] [Accepted: 02/04/2008] [Indexed: 10/22/2022]
Abstract
Decision analytic policy models for Alzheimer's disease (AD) enable researchers and policy makers to investigate questions about the costs and benefits of a wide range of existing and potential screening, testing, and treatment strategies. Such models permit analysts to compare existing alternatives, explore hypothetical scenarios, and test the strength of underlying assumptions in an explicit, quantitative, and systematic way. Decision analytic models can best be viewed as complementing clinical trials both by filling knowledge gaps not readily addressed by empirical research and by extrapolating beyond the surrogate markers recorded in a trial. We identified and critiqued 13 distinct AD decision analytic policy models published since 1997. Although existing models provide useful insights, they also have a variety of limitations. (1) They generally characterize disease progression in terms of cognitive function and do not account for other distinguishing features, such as behavioral symptoms, functional performance, and the emotional well-being of AD patients and caregivers. (2) Many describe disease progression in terms of a limited number of discrete states, thus constraining the level of detail that can be used to characterize both changes in patient status and the relationships between disease progression and other factors, such as residential status, that influence outcomes of interest. (3) They have focused almost exclusively on evaluating drug treatments, thus neglecting other disease management strategies and combinations of pharmacologic and nonpharmacologic interventions. Future AD models should facilitate more realistic and compelling evaluations of various interventions to address the disease. An improved model will allow decision makers to better characterize the disease, to better assess the costs and benefits of a wide range of potential interventions, and to better evaluate the incremental costs and benefits of specific interventions used in conjunction with other disease management strategies.
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Affiliation(s)
- Joshua T Cohen
- Center for the Evaluation of Value and Risk in Health, Institute for Clinical Research and Health Policy Studies, Tufts-New England Medical Center, Boston, MA, USA.
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Seltzer B. Is long-term treatment of Alzheimer's disease with cholinesterase inhibitor therapy justified? Drugs Aging 2008; 24:881-90. [PMID: 17953456 DOI: 10.2165/00002512-200724110-00001] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The cholinesterase inhibitors (ChEIs) donepezil, rivastigmine and galantamine are the current mainstays in the drug treatment of Alzheimer's disease (AD). There is convincing evidence that these agents provide at least modest cognitive, behavioural and functional benefit for 6-12 months at all stages of the disease. Longer term benefits cannot be directly examined by placebo-controlled trials. Nevertheless, the results of virtually all open-label extensions of the pivotal trials, studies of patients with AD at different levels of severity and clinical trials using other designs favour treatment over no treatment for periods of up to 5 years. There are plausible biological reasons why ChEIs might be expected to work over a prolonged period of time although, to date, studies using various markers to chart the effects of medication on long-term disease progression have yielded mixed results. The most contentious issue regarding long-term treatment is economic, but the majority of available economic analyses suggest net savings over the long term if patients with AD receive persistent treatment with ChEIs.
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Affiliation(s)
- Ben Seltzer
- Department of Neurology, Harvard Medical School, Boston, Massachusetts, USA.
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Kirbach S, Simpson K, Nietert PJ, Mintzer J. A Markov Model of the Cost Effectiveness of Olanzapine Treatment for Agitation and Psychosis??in Alzheimer??s Disease. Clin Drug Investig 2008; 28:291-303. [DOI: 10.2165/00044011-200828050-00003] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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Fuh JL, Wang SJ. Cost-effectiveness analysis of donepezil for mild to moderate Alzheimer's disease in Taiwan. Int J Geriatr Psychiatry 2008; 23:73-8. [PMID: 17520661 DOI: 10.1002/gps.1842] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Donepezil is a drug used for treatment in patients with Alzheimer's disease (AD). Information regarding the cost-effectiveness of this medication was previously rare in Asia. We used techniques of decision analysis and economic evaluation in conjunction with available local epidemiological and clinical data on costs of mild to moderate AD to assess the cost-effectiveness of donepezil in Taiwan. METHODS A four-state Markov model was built to simulate the disease progression of AD patients. Local transition probabilities and costs of different stages were from the studies published earlier. RESULTS Over a 5-year span, donepezil treatment for mild or moderate AD patients is predicted to result in the gain of 0.505 QALYs when comparing to usual care, while at the same time reducing the cost by US$7,691. The incremental cost was US$3,647 from the payer perspective; thus, the incremental cost-effectiveness ratio was estimated to be US$7,226 when considering only the medical expenditures. CONCLUSIONS Under some assumptions, donepezil treatment might be a cost saving strategy for mild to moderate AD patients in Taiwan from a societal perspective. It is inconclusive from the payer's part since we still lack a consensus for judging the cost-effectiveness of a new health care technology.
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Affiliation(s)
- Jong-Ling Fuh
- Neurological Institute, Taipei Veterans General Hospital and National Yang-Ming University School of Medicine, Taipei, Taiwan.
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Lanctôt KL, Herrmann N. Commentary on “Health economics and the value of therapy in Alzheimer's disease.” Cholinesterase inhibitors in Alzheimer's disease—Evidence‐based or evidence‐biased? Alzheimers Dement 2007; 3:177-9. [DOI: 10.1016/j.jalz.2007.04.389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2007] [Accepted: 04/26/2007] [Indexed: 11/29/2022]
Affiliation(s)
- Krista L. Lanctôt
- Psychopharmacology Research Program and Department of PsychiatrySunnybrook Health Sciences Center and Departments of Psychiatry and PharmacologyUniversity of TorontoTorontoOntarioCanada
| | - Nathan Herrmann
- Psychopharmacology Research Program and Department of PsychiatrySunnybrook Health Sciences Center and Departments of Psychiatry and PharmacologyUniversity of TorontoTorontoOntarioCanada
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Abstract
Donepezil hydrochloride is the most widely prescribed drug for Alzheimer's disease (AD). The main mechanism of action through which it influences cognition and function is presumed to be the inhibition of acetylcholinesterase enzyme in the brain; however, donepezil may also impact the pathophysiology of AD at several other points. Officially approved for mild-to-moderate and severe AD, donepezil has also been shown to be effective in early-stage AD, vascular dementia, Parkinson's disease dementia/Lewy body disease and cognitive symptoms associated with multiple sclerosis. In addition, one study suggested that donepezil may delay the onset of AD in subjects with mild cognitive impairment, a prodrome to AD. The pharmacokinetics, pharmacodynamics, safety/tolerability profile and drug interaction properties of donepezil make it an easy and safe agent to use. However, in general, the efficacy of donepezil is limited, and ongoing studies are investigating other agents that may ultimately overtake its present position as the mainstay of anti-AD therapy.
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Affiliation(s)
- Ben Seltzer
- V.A. Boston Healthcare System, Department of Neurology, Harvard Medical School, Geriatric Research Center, Boston, MA 02130, USA.
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Green C. Modelling disease progression in Alzheimer's disease: a review of modelling methods used for cost-effectiveness analysis. PHARMACOECONOMICS 2007; 25:735-50. [PMID: 17803333 DOI: 10.2165/00019053-200725090-00003] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
The literature reporting economic evaluations related to the treatment of Alzheimer's disease (AD) has developed over the last decade. Most analyses have used economic models to estimate the cost effectiveness of drugs for the treatment of AD. This review considers the range of methods used in the published cost-effectiveness literature to model AD progression and the effect of interventions on the progression of AD. The review builds on and updates an earlier systematic review of cost-effectiveness studies on drugs for AD. Systematic and rigorous methods were used to search the literature for economic evaluations estimating the cost effectiveness of donepezil, rivastigmine, galantamine or memantine in AD. The literature search covered a wide range of electronic databases (e.g. MEDLINE, EMBASE), and included literature from the inception of databases up to the end of 2005. The search identified 22 published economic evaluations. An outline and brief critical review of the identified studies is provided, and thereafter the methods used to model disease progression were considered in more detail. The review employs recent guidance on good practice in decision-analytic modelling in HTA to critically review the modelling methods used. Using this guidance, the models are assessed against the broad criteria of model structure, data inputs and assessment of uncertainty and inconsistency. Concerns were noted over the model structure employed in all models. The reliance on cognitive scores to model AD, the progression of the disease, and the effect of treatment on costs and consequences is regarded as a serious limitation in almost all of the studies identified. There are also limitations over the data used to populate published models, especially around the failure of studies to document and establish the basis for the modelling of treatment effects. It is also clear that studies modelling AD progression, and subsequently the cost effectiveness of treatment, have not addressed uncertainty or consistency (internal and/or external) in sufficient detail. Further research is required on more appropriate methods for the modelling of AD progression. In the meantime, future economic evaluations of treatment need to be more explicit on the methods used to model AD, and the data used to populate models.
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Affiliation(s)
- Colin Green
- Institute for Health Service Research, Peninsula Medical School, University of Exeter, Exeter, UK.
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Abstract
PURPOSE OF REVIEW In the absence of a specific treatment for dementia, the effective management of cognitive symptoms is a clinical priority. RECENT FINDINGS Although some differences have been observed in the profile of cognitive complaints observed in subtypes of dementia, there is increasing recognition of common, interacting neurobiological causes suggesting the need to seek a common treatment applicable to all causes of cognitive deterioration. There also exists increasing interest in intervening at the level of minor cognitive dysfunction by reducing risk factors for subclinical states. SUMMARY Pharmacological treatment of cognitive disorder is beneficial but has only temporary benefit for a subgroup of patients. Pharmacogenetics may have an important future role to play in deciding which patients may best benefit from the treatment. Low side effect therapies such as cognitive therapy and acupuncture show some benefits but their utility in combination with pharmacotherapies remains to be demonstrated. Prevention of milder forms of cognitive disorder by controlling risk factors such as hypertension and diabetes may reduce rates of more severe cognitive degeneration. Persons with cognitive dysfunction are commonly excluded from making decisions about the implementation of cognition-enhancing treatments although they wish to do so.
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Affiliation(s)
- Karen Ritchie
- French National Institute of Health and Medical Research (INSERM), Unit E361 Pathologies of the Nervous System, La Colombière Hospital, Montpellier, France.
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Bosanquet N, Yeates A. Modelling the cost effectiveness of cholinesterase inhibitors in the management of mild to moderately severe Alzheimer's disease. PHARMACOECONOMICS 2006; 24:623-5; author reply 625-6. [PMID: 16761908 DOI: 10.2165/00019053-200624060-00008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
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