Long-term efficacy and safety of donepezil in the treatment of Alzheimer's disease: final analysis of a US multicentre open-label study

Acetylcholinesterase inhibitors for Alzheimer’s disease

Acetylcholinesterase inhibitor drugs are now a mature treatment approach for Alzheimer’s disease, although they remain controversial. This review addresses the available data on acetylcholinesterase inhibitor treatment in patients with Alzheimer’s disease across multiple outcome types. It addresses rational and evidence-based expectations for treatment in this population.

Effectiveness of treatment with donepezil hydrochloride and changes in regional cerebral blood flow in patients with Alzheimer's disease

OBJECTIVE

The objective of this study was to elucidate the relationship between the effects of donepezil hydrochloride (donepezil) and cerebral blood flow, and to evaluate the usefulness of cerebral blood flow imaging in assessing and predicting treatment effectiveness.

METHODS

The subjects were 29 outpatients (12 men and 17 women; age 50-82 years; mean age 69.2 years), who had received a diagnosis of Alzheimer's disease (AD). Efficacy was evaluated before donepezil administration; after 1 month, 3 months, and 6 months of drug administration; and at 1 year after completion of administration using the Japanese version of the Alzheimer's disease assessment scale-cognitive subscale (ADAS-cog), as a measure of cognitive function. The ADAS-cog has been frequently used to evaluate cognitive function in AD patients. Patients whose ADAS-cog scores improved by 3 or more points during the observation period were classified as responders, and those with no improvement were classified as nonresponders. (123)I-IMP was used for single photon emission computed tomography cerebral blood flow scintigraphy.

RESULTS

On the basis of ADAS-cog score improvement, 22 of the 29 patients were responders (7 men and 15 women; age 50-82 years; mean age 69.0 years) and seven were nonresponders (5 men and 2 women; age 61-80 years; mean age 70.0 years). The results indicate that a difference in cerebral blood flow responsiveness after 1 month of treatment distinguishes responders from nonresponders. After 1 month, blood flow was significantly decreased in all regions of nonresponders, whereas significant increases in blood flow were seen in the anterior frontal lobe and parietal lobe of responders. At that time point, blood flow in the basal ganglion differed significantly between the two groups, indicating that this difference in responsiveness after 1 month of treatment may distinguish responders from nonresponders.

CONCLUSIONS

In cognitive function testing, the group that exhibited a complete response showed improvement primarily in parameters reflecting frontal lobe function. Complete responders also showed significantly greater blood flow increases in the basal ganglion and thalamus early during the treatment period. This indicates that the drug responsiveness of the basal ganglion and thalamus affects frontal lobe function and distinguishes complete responders from patients who do not exhibit such a response.

Commentary on "Health economics and the value of therapy in Alzheimer's disease." Value therapy for Alzheimer's disease--a European perspective

The overall goal of value therapy is to provide the most efficient use of resources, taking into account both the cost and the value derived from a given technology or drug, and to assist in healthcare decision-making, because both cost and effectiveness are considered. After a short review of European Medicines Agency (EMEA) Committee for Medicinal Products for Human Use (CHMP) recommendations for the development of medications for Alzheimer's disease, we focus on the evidence with respect to cost and benefits obtained so far with acetylcholinesterase inhibitor (AChEI) and Memantine in the treatment of Alzheimer's disease. We then analyze the recommendations developed by professionals for the treatment of Alzheimer's disease at the national level in European countries, and finally we discuss how to utilize this process more homogenously in the future to assess value therapeutic values in Alzheimer's disease.

Acetylcholinesterase inhibitors and depressive symptoms in patients with mild to moderate Alzheimer's disease

BACKGROUND AND AIMS

Acetylcholinesterase inhibitor (AChEis) therapy in Alzheimer Disease (AD) has been shown to provide cognitive benefits and to slow progression of the disease. AChEis have also been demonstrated to improve behavioral symptoms, although there seem to be subtle differences in the magnitude of response. The aim of our study was to evaluate the effect of 16 weeks treatment with AChEis on depressive symptoms in a selected sample of AD patients in routine clinical practice.

SUBJECTS AND METHODS

A study of 135 patients with Alzheimer's disease. All subjects were assessed at baseline (upon initiation of AChEis therapy) and re-evaluated after 16 weeks.

RESULTS

At baseline, "Depressed" and "Not depressed" patients were categorized according to DSM IV criteria for depression in Alzheimer Disease. After 16 weeks of treatment with AchEis, we observed an improvement of mood in the "Depressed" patients. In this group "Mood symptoms", measured with GDS, were independently associated with GDS "Mood symptoms" at baseline, but not with improvement on cognition (mean change of MMSE), age or sex.

CONCLUSIONS

In depressed AD subjects, AChEis treatment improves depressive symptoms evaluated by GDS. This improvement is independent of cognition enhancement.

Donepezil in Alzheimer's disease: what to expect after 3 years of treatment in a routine clinical setting

BACKGROUND/AIMS

Clinical short-term trails have shown positive effects of donepezil treatment in patients with Alzheimer's disease. The outcome of continuous long-term treatment in the routine clinical settings remains to be investigated.

METHODS

The Swedish Alzheimer Treatment Study (SATS) is a descriptive, prospective, longitudinal, multicentre study. Four hundred and thirty-five outpatients with the clinical diagnosis of Alzheimer's disease, received treatment with donepezil. Patients were assessed with Mini-Mental State Examination (MMSE), Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog), global rating (CIBIC) and Instrumental Activities of Daily Living (IADL) at baseline and every 6 months for a total period of 3 years.

RESULTS

The mean MMSE change from baseline was positive for more than 6 months and in subgroups of patients for 12 months. After 3 years of treatment the mean change from baseline in MMSE-score was 3.8 points (95% CI, 3.0-4.7) and the ADAS-cog rise was 8.2 points (95% CI, 6.4-10.1). This is better than expected in untreated historical cohorts, and better than the ADAS-cog rise calculated by the Stern equation (15.6 points; 95% CI, 14.5-16.6). After 3 years with 38% of the patients remaining, 30% of the them were unchanged or improved in the global assessment.

CONCLUSION

Three-year donepezil treatment showed a positive global and cognitive outcome in the routine clinical setting.

Recommendations for the diagnosis and management of Alzheimer's disease and other disorders associated with dementia: EFNS guideline

The aim of this international guideline on dementia was to present a peer-reviewed evidence-based statement for the guidance of practice for clinical neurologists, geriatricians, psychiatrists, and other specialist physicians responsible for the care of patients with dementia. It covers major aspects of diagnostic evaluation and treatment, with particular emphasis on the type of patient often referred to the specialist physician. The main focus is Alzheimer's disease, but many of the recommendations apply to dementia disorders in general. The task force working group considered and classified evidence from original research reports, meta-analysis, and systematic reviews, published before January 2006. The evidence was classified and consensus recommendations graded according to the EFNS guidance. Where there was a lack of evidence, but clear consensus, good practice points were provided. The recommendations for clinical diagnosis, blood tests, neuroimaging, electroencephalography (EEG), cerebrospinal fluid (CSF) analysis, genetic testing, tissue biopsy, disclosure of diagnosis, treatment of Alzheimer's disease, and counselling and support for caregivers were all revised when compared with the previous EFNS guideline. New recommendations were added for the treatment of vascular dementia, Parkinson's disease dementia, and dementia with Lewy bodies, for monitoring treatment, for treatment of behavioural and psychological symptoms in dementia, and for legal issues. The specialist physician plays an important role together with primary care physicians in the multidisciplinary dementia teams, which have been established throughout Europe. This guideline may contribute to the definition of the role of the specialist physician in providing dementia health care.

Pain with donepezil

An 85-year-old lady with a 4-year history of Alzheimer's dementia was started on a dose of 5 mg of Donepezil. Improvements were noted in her overall mental state with an associated reduction in the level of carer stress but with mild and transient subjective gastrointestinal complaints. Therefore, the dose was cautiously increased to 10 mg. But within 10 days of the increase, she reported bilateral leg pain severe enough to cause her mental state to deteriorate significantly. Pain induced by Donepezil undermined the efficacy of the drug, resulted in increased carer stress and worsening cognition not reversed by the change of medication to another cholinesterase inhibitor.

3-year study of donepezil therapy in Alzheimer's disease: effects of early and continuous therapy

Delays in the diagnosis of Alzheimer's disease, and, therefore, delays in treatment, may have a detrimental effect on a patient's long-term well-being. This study assessed the effects of postponing donepezil treatment for 1 year by comparing patients treated continuously for 3 years with those who received placebo for 1 year followed by open-label donepezil for 2 years. Patients (n = 286) with possible or probable Alzheimer's disease (according to DSM-IV, NINCDS-ADRDA, and Mini-Mental State Examination criteria; see text) were randomized to receive donepezil (5 mg/day for 4 weeks, 10 mg/day thereafter) or placebo (delayed-start group) for 1 year. Of the 192 completers, 157 began a 2-year, open-label phase of donepezil treatment. Outcome measures were the Gottfries-Bråne-Steen scale, the Mini-Mental State Examination, the Global Deterioration Scale, the Progressive Deterioration Scale, the Neuropsychiatric Inventory, and safety (adverse events). Mixed regression analysis was used to compare changes between the groups over 3 years on the efficacy measures. There was a trend for patients receiving continuous therapy to have less global deterioration (Gottfries-Bråne-Steen scale) than those who had delayed treatment (p = 0.056). Small but statistically significant differences between the groups were observed for the secondary measures of cognitive function (Mini-Mental State Examination; p = 0.004) and cognitive and functional abilities (Global Deterioration Scale; p = 0.0231) in favor of continuous donepezil therapy. Over 90% of the patients in both cohorts experienced one treatment-emergent adverse event; most were considered mild or moderate. In conclusion, patients in whom the start of treatment is delayed may demonstrate slightly reduced benefits as compared with those seen in patients starting donepezil therapy early in the course of Alzheimer's disease. These data support the long-term efficacy and safety of donepezil.

Cholinesterase inhibitors in the clinical management of Alzheimer's disease: importance of early and persistent treatment

Alzheimer's disease is a neurodegenerative disease that greatly affects the quality of life of patients and their caregivers and places a heavy cost burden on the healthcare system. The cholinesterase inhibitors (ChEIs) donepezil, rivastigmine and galantamine have a central role in the treatment of Alzheimer's disease in the mild to moderate stages. Clinical trials with ChEIs have demonstrated therapeutic benefits for symptoms of cognition, function and behaviour across the disease course. These agents are most effective when started early in the disease course and used persistently, without treatment gaps. Early recognition of Alzheimer's disease and a global evaluation of treatment effectiveness are therefore essential. This article identifies barriers to early recognition and effective care of patients with Alzheimer's disease and discusses practical strategies to overcome them.

Assessing therapeutic efficacy in a progressive disease: a study of donepezil in Alzheimer's disease

OBJECTIVE

To determine the value of continued donepezil treatment in patients with Alzheimer's disease for whom clinical benefit was initially judged to be uncertain.

METHODS

The study consisted of three phases: (i) a 12- to 24-week, pre-randomisation, open-label donepezil-treatment phase; (ii) a 12-week, randomised, double-blind, placebo-controlled phase; and (iii) a 12-week, single-blind (i.e. patient-blind) donepezil-treatment phase. Patients with mild to moderate Alzheimer's disease received open-label treatment with donepezil (5 mg/day for 4 weeks, then 10 mg/day for the remainder of the phase) for 12-24 weeks. Patients who exhibited a decline or no change from baseline on the Mini-Mental State Examination (MMSE) and whose physician was not sufficiently certain of clinical benefit to warrant continued treatment were randomised into the double-blind phase in which patients received 12 weeks of treatment with donepezil (10 mg/day) or placebo. At the end of the double-blind phase, donepezil-treated patients continued to receive donepezil, while placebo-treated patients were rechallenged with donepezil, in a 12-week single-blind phase. Patients were assessed at the start of the double-blind phase and at weeks 6 and 12 of this phase, and at the end of the single-blind phase.

RESULTS

Six hundred and nineteen patients completed the open-label phase; 69% showed clear clinical benefit and 31% showed uncertain benefit. 202 patients were randomised to continued donepezil treatment (n = 99) or placebo (n = 103). Differences in favour of continued donepezil versus placebo were observed in cognition and behaviour. In addition, there was a non-significant trend favouring donepezil in activities of daily living (ADL) [week 12 observed case mean treatment differences: MMSE, 1.13 (p = 0.02); Alzheimer's Disease Assessment Scale - cognitive subscale, 0.57 (p = 0.5); the Neuropsychiatric Inventory, -3.16 (p = 0.02); Disability Assessment for Dementia scale, 3.67 (p = 0.1)].

CONCLUSION

Most patients showed clear clinical benefit during initial donepezil treatment. Among patients for whom clinical benefit was uncertain, improvement in cognition and behaviour were observed for those who continued donepezil treatment compared with the group switched to placebo. Initial decline or stabilisation does not necessarily indicate a lack of efficacy in Alzheimer's disease, and the decision to discontinue treatment should be based on an evaluation of all domains (cognition, behaviour and ADL) and performed at several timepoints.

Utilizing combination therapy in the treatment of Alzheimer's disease

Alzheimer's disease may not yet be curable, but it is treatable. Two classes of drugs with differing mechanisms of action have received Food and Drug Administration approval for the treatment of Alzheimer's disease: the cholinesterase inhibitors and the N-methyl-D-aspartate receptor antagonist memantine (Ebixa, Lundbeck; Namenda, Forest Laboratories). Alzheimer's disease research directed at increasing the understanding of the underlying disease process has led to the identification of several other potential targets for drug development strategies. Due to the complexity of the disease, it is possible that combination therapy -- concomitant use of agents with nonoverlapping or even synergistic mechanisms of action -- may represent the best means available to enhance treatment effectiveness. This review evaluates the available data on combination therapy in Alzheimer's disease and provides an expert opinion on the use and implementation of combination therapy in clinical practice.

What Constitutes Clinical Evidence for Neuroprotection in Alzheimer Disease

The progression of Alzheimer disease (AD) corresponds to a prolonged course of neuronal loss in the cerebral cortex. Strategies aimed at reducing the rates of neuronal loss are therefore particularly important. The clinical measures to evaluate the disease-modifying effect of an intervention are readily confounded by any symptomatic benefit of the intervention. Thus, when testing putative neuroprotective agents that are known to have symptomatic effects, it can be difficult to separate the 2 effects. The hypothesis that cholinesterase inhibitors (ChEIs) only treat symptoms caused by cholinergic imbalances in AD is overly simplistic. Evidence has now accumulated that ChEIs have a neuroprotective, disease-modifying property. In this paper, to answer the question of what constitutes clinical evidence for neuroprotection in AD, we have reviewed clinical studies with specific designs, including "delaying end point," "withdrawal," and "randomized start" designs. We have also reviewed data on surrogate biomarkers of disease progression that may indicate a disease-modifying action. In addition, we have reviewed evidence indicating that ChEIs may protect cells in the brain of patients with AD. Among the clinical data suggesting a possible neuroprotective effect of ChEIs, the most rigorous published evidence comes from magnetic resonance imaging (MRI) hippocampal volumetric studies with donepezil.

Recognition and treatment of Alzheimer's disease: a case-based review

Early recognition and treatment initiation are pivotal in managing Alzheimer's disease (AD). Once a diagnosis of AD is made, a treatment plan is developed and should include treatment initiation with cholinesterase inhibitors (ChEIs) to improve cognition, management of comorbid conditions, and treat behavioral symptoms. Caregiver compliance is integral to AD treatment success. The purpose of this report is to present two real case studies of "suspected" AD or related dementia and stress the significance of early and accurate diagnosis in disease management. In case 1, a caregiver reports gradual but progressive loss of memory, and the patient himself complains of memory impairment. Neuroimaging analysis confirms "typical " AD. In case 2, initiation of ChEI therapy is followed by substantial clinical improvement in the face of a complex medical picture, and neuroimaging revealing more neurodegenerative changes than could be accounted for by "pure" AD.

SPECT Follow-Up Study of Cerebral Blood Flow Changes During Donepezil Therapy in Patients with Alzheimer's Disease

BACKGROUND AND PURPOSE

Treatment with acetylcholinesterase inhibitors (AchEIs) is beneficial for patients with Alzheimer's disease (AD). But the clinical response varies. Functional neuroimaging techniques might allow objective evaluation of the topographic correlates of the effect of therapy on brain functioning. We attempted to evaluate the possible correlation between regional cerebral blood flow (rCBF) differences in patients with AD and response to donepezil hydrochloride (Donepezil) therapy.

METHODS

The subjects of this study were 51 consecutive patients with AD receiving Donepezil who underwent SPECT at baseline and 10-14 months later. We divided the patients into stabilized (n = 19) and nonstabilized (n = 32) subgroups based on changes in the Mini Mental State Examination (MMSE) score. Analysis of single-photon emission computed tomography (SPECT) data was done using 3-dimensional stereotactic surface projections (3D-SSP) and the stereotactic extraction estimation (SEE) method. We compared differences in rCBF between the two subgroups at baseline and follow-up, and between the baseline and follow-up in each subgroup.

RESULTS

Significant correlation was recognized between the mean Z score changes of the left frontal lobe, left limbic lobe, and MMSE change. There were no significant baseline differences in rCBF in any region of the brain between the two subgroups. At the study endpoint, the nonstabilized subgroup showed lower rCBF in the lateral and medial frontal lobes, limbic lobe, lower lateral temporal lobe, and cingulate gyrus compared to the stabilized subgroup. Both patient groups showed a significant post-treatment increase over baseline values in the frontal lobe, and the stabilized group had more extensive and intense increases in the lateral and medial frontal lobes and orbital surface.

CONCLUSIONS

Our study suggests that the diversity of clinical responses to Donepezil therapy in patients with AD is associated with rCBF changes, mainly in the frontal lobe. SPECT may be a promising tool to assess the impact of AchEI therapy on the brain function of patients with AD.

Current Pharmacotherapy for Alzheimer's Disease

Alzheimer's disease (AD) is an age-related neurodegenerative disease that affects approximately 4.5 million people in the United States. The mainstays of current pharmacotherapy for AD are compounds aimed at increasing the levels of acetylcholine in the brain, thereby facilitating cholinergic neurotransmission through inhibition of the cholinesterases. These drugs, known as acetylcholinesterase inhibitors (AChEIs), were first approved by the U.S. Food and Drug Administration (FDA) in 1995 based on clinical trials showing modest symptomatic benefit on cognitive, behavioral, and global measures. In 2004 the FDA approved memantine, an NMDA antagonist, for treating dementia symptoms in moderate to severe AD cases. In clinical practice, memantine may be co-administered with an AChEI, although neither drug individually or in combination affects the underlying pathophysiology of dementia. Dementia in AD results from progressive synaptic loss and neuronal death. As knowledge of the mechanisms responsible for neurodegeneration in AD increases, it is anticipated that neuroprotective drugs to slow or prevent neuronal dysfunction and death will be developed to complement current symptomatic treatments.

Donepezil for dementia due to Alzheimer's disease

BACKGROUND

Alzheimer's disease is the most common cause of dementia in older people. One of the aims of therapy is to inhibit the breakdown of a chemical neurotransmitter, acetylcholine, by blocking the relevant enzyme. This can be done by a group of chemicals known as cholinesterase inhibitors.

OBJECTIVES

The objective of this review is to assess whether donepezil improves the well-being of patients with dementia due to Alzheimer's disease.

SEARCH STRATEGY

The Cochrane Dementia and Cognitive Improvement Group's Specialized Register was searched using the terms 'donepezil', 'E2020' and 'Aricept' on 12 June 2005. This Register contains up-to-date records of all major health care databases and many ongoing trial databases. Members of the Donepezil Study Group and Eisai Inc were contacted.

SELECTION CRITERIA

All unconfounded, double-blind, randomized controlled trials in which treatment with donepezil was compared with placebo for patients with mild, moderate or severe dementia due to Alzheimer's disease.

DATA COLLECTION AND ANALYSIS

Data were extracted by one reviewer (JSB), pooled where appropriate and possible, and the pooled treatment effects, or the risks and benefits of treatment estimated.

MAIN RESULTS

23 trials are included, involving 5272 participants. Most trials were of 6 months or less duration in selected patients. Available outcome data cover domains including cognitive function, activities of daily living, behaviour , global clinical state and health care resource costs. For cognition there is a statistically significant improvement for both 5 and 10 mg/day of donepezil at 24 weeks compared with placebo on the ADAS-Cog scale (-2.01 points MD, 95%CI -2.69 to -1.34, p<0.00001); -2.80 points, MD 95% CI -3.74 to -2.10, p<0.00001) and for 10 mg/day donepezil compared with placebo at 52 weeks (1.84 MMSE points, 95% CI, 0.53 to 3.15, p=0.006). The results show some improvement in global clinical state (assessed by a clinician) in people treated with 5 and 10 mg/day of donepezil compared with placebo at 24 weeks for the number of patients showing improvement or no change (OR 2.18, 95% CI 1.53 to 3.11, p=<0.0001, OR 2.38, 95% CI 1.78 to 3.19, p<0.00001). Benefits of treatment were also seen on measures of activities of daily living and behaviour, but not on the quality of life score . There were significantly more withdrawals before the end of treatment from the 10 mg/day (but not the 5 mg/day) donepezil group compared with placebo which may have resulted in some overestimation of beneficial changes at 10 mg/day. Benefits on the 10 mg/day dose were marginally larger than on the 5 mg/day dose. Two studies presented results for health resource use, and the associated costs. There were no significant differences between treatment and placebo for any item, the cost of any item, and for the total costs, and total costs including the informal carer costs. A variety of adverse effects were recorded, with more incidents of nausea, vomiting, diarrhoea, muscle cramps, dizziness, fatigue and anorexia (significant risk associated with treatment) in the 10 mg/day group compared with placebo but very few patients left a trial as a direct result of the intervention.

AUTHORS' CONCLUSIONS

People with mild, moderate or severe dementia due to Alzheimer's disease treated for periods of 12, 24 or 52 weeks with donepezil experienced benefits in cognitive function, activities of daily living and behaviour. Study clinicians rated global clinical state more positively in treated patients, and measured less decline in measures of global disease severity. There is some evidence that use of donepezil is neither more nor less expensive compared with placebo when assessing total health care resource costs. Benefits on the 10 mg/day dose were marginally larger than on the 5 mg/day dose. Taking into consideration the better tolerability of the 5 mg/day donepezil compared with the 10 mg/day dose, together with the lower cost, the lower dose may be the better option. The debate on whether donepezil is effective continues despite the evidence of efficacy from the clinical studies because the treatment effects are small and are not always apparent in practice .

Recommendations for best practices in the treatment of Alzheimer's disease in managed care

BACKGROUND

Alzheimer's disease and related dementias (ADRDs) are increasingly recognized as important causes of impaired cognition, function, and quality of life, as well as excess medical care utilization and costs in the elderly Medicare managed care population. Evidence-based clinical practice guidelines for ADRDs were published in 2001. More recent studies have resulted in the approval of new agents and demonstrated an expanded role for antidementia therapy in various types of dementia, settings of care, stages of disease, and the use of combination therapy. However, these clinical guidelines have not been updated in the past few years.

OBJECTIVE

The goal of this article was to provide practical recommendations developed by a panel of experts that address issues of early diagnosis, treatment, and care management of ADRDs. The panel also addressed the societal and managed care implications.

METHODS

A panel of leading experts was convened to develop consensus recommendations for the treatment and management of dementia based on currently available evidence and the panel's informed expert opinion. The panel comprised 12 leading experts, including clinical investigators and practitioners in geriatric medicine, neurology, psychiatry, and psychology; managed care medical and pharmacy directors; a health systems medical director; and a health policy expert. In addition, articles were collected based on PubMed searches (2000-2005) that were relevant to the key issues identified. Search terms included Alzheimer's disease, dementia, clinical practice guidelines, clinical trials, screening and assessment, and managed care.

RESULTS

ADRDs represent a significant clinical and economic burden to individuals and society, including Medicare managed care organizations (MCOs). Appropriate utilization of antidementia therapy and care management is vitally important to achieving quality of life and care for dementia patients and their caregivers, and for managing the excess costs of Alzheimer's disease. The recommendations address relevant, practical, and timely concerns that are faced on a daily basis by practitioners and by Medicare MCO medical management programs in the care of dementia patients. These consensus recommendations attempt to describe a reasonable current standard for the provision of quality care for patients with dementia. The panel recommendations support the use of screening for cognitive impairment and the use of antidementia therapy for ADRDs in different stages of disease and types of dementia in all clinical settings. The panel members evaluated the use of the 3 marketed cholinesterase inhibitors-donepezil, galantamine, and rivastigmine-as well as the N-methyl-D-aspartate antagonist memantine. Recommendations for using these medications are made with an appreciation of the difficulties in translating the results from investigational clinical trials into clinical practice.

CONCLUSIONS

The recommendations of the expert panel represent a clear consensus that nihilism in the diagnosis, treatment, and management of ADRDs is unwarranted, impairs quality of care, and is ultimately not costeffective.

Apolipoprotein E epsilon4 allele differentiates the clinical response to donepezil in Alzheimer's disease

The existence of an association between apolipoprotein E (APOE) and Alzheimer's disease (AD) has been reported in several studies. The possession of an ApoE epsilon4 allele is now considered a genetic risk factor for sporadic AD. There has been a growing agreement about the role exerted by the ApoE epsilon4 allele on the neuropsychological profile and the rate of cognitive decline in AD patients. However, a more controversial issue remains about a possible influence of the APOE genotype on acetylcholinesterase inhibitor therapy response in AD patients. In order to address this issue, 81 patients diagnosed as having probable AD were evaluated by a complete neuropsychological test battery at the time of diagnosis (baseline) and after 12-16 months (retest). Patients were divided into two subgroups: (1) treated with donepezil at a dose of 5 mg once a day (n = 41) and (2) untreated (n = 40). Donepezil therapy was started after baseline evaluation. The APOE genotype was determined according to standardized procedures. We evaluated the possible effect of the APOE genotype on the neuropsychological tasks in relation to donepezil therapy. The statistical analysis of the results showed a global worsening of cognitive performances for all AD patients at the retest. Differences in the clinical outcome were analysed in the four subgroups of AD patients for each neuropsychological task. ApoE epsilon4 carriers/treated patients had improved or unchanged scores at retest evaluation for the following tasks: visual and verbal memory, visual attention and inductive reasoning and Mini Mental State Examination. These results indicate an effect of donepezil on specific cognitive domains (attention and memory) in the ApoE epsilon4 carriers with AD. This might suggest an early identification of AD patients carrying at least one epsilon4 allele as responders to donepezil therapy.

Drug persistency of two cholinesterase inhibitors: rivastigmine versus donepezil in elderly patients with Alzheimer's disease

OBJECTIVES

To compare persistency rates and persistency days in patients with Alzheimer's disease (AD) who initiated therapy with either rivastigmine or donepezil, and to identify factors influencing persistency in a real-world setting.

DESIGN AND METHODS

This study used data collected by MarketScan from 1 January 1999 to 31 December 2002. Patients were included if they were newly diagnosed with AD and filled at least one prescription for rivastigmine or donepezil between 1 July 2000 and 30 June 2001, were > or =65 years of age on the index prescription date, and had continuous health and prescription insurance during the entire study period. Patients were excluded if they filled a prescription for any cholinesterase inhibitor during the 18 months prior to initiation of the study drugs. Patients who refilled their initial cholinesterase inhibitor prescription within a permissible gap of 60 days after depleting the drug supply from the prior prescription were considered to be persistent. Sensitivity analysis was performed to test the robustness of the persistency definition. The Kaplan-Meier method was used to determine persistency rates across time and Cox proportional hazards models were used to estimate relative risks of discontinuation or switch with adjustment for other covariates, and to identify factors significantly influencing persistency of the study drugs.

RESULTS

Of the newly treated AD patients, the proportion of rivastigmine and donepezil patients who continued their medication was the same (47%; p = 0.5). On average, rivastigmine users continuously used their medication for 234 days (median 312 days) while those taking donepezil used their medication for 235 days (median 315 days) [p = 0.91]. Patients were more likely to discontinue or switch their initial cholinesterase inhibitor if they used a central nervous system (CNS) medication before initiation of therapy (relative risk [RR] = 1.23; 95% CI 1.01, 1.51 without adjustment for study variables; RR = 1.30; 95% CI 1.05, 1.60 with adjustment for study variables). On the other hand, patients were less likely to discontinue their cholinesterase inhibitor if they visited their physician office frequently (RR = 0.24; 95% CI 0.18, 0.32 without adjustment; RR = 0.23; 95% CI 0.17, 0.30 with adjustment) or if they were hospitalised after initiation of their cholinesterase inhibitor therapy (RR = 0.60; 95% CI 0.39, 0.91 without adjustment; RR = 0.65; 95% CI 0.42, 0.99 with adjustment).

CONCLUSION

Patients who were newly diagnosed with AD and initiated therapy with either rivastigmine or donepezil had similar levels of persistency with their initial AD therapy in a real-world setting.

Donepezil: a review

Donepezil is a selective acetylcholinesterase inhibitor that is widely prescribed for Alzheimer's disease (AD). It has been shown to be of benefit in mild, moderate and severe stages of AD, vascular dementia and dementia associated with Parkinson's disease. Donepezil is absorbed slowly, but completely, from the gut, reaching peak plasma levels in 3-4 h and, with daily dosing, steady-state concentration in 15-21 days. Within a relatively narrow range, there is a linear relationship between dose and pharmacodynamic effects, measured as red blood cell acetylcholinesterase inhibition and clinical efficacy. Donepezil is principally excreted unchanged in the urine, but there is also hepatic metabolism; some of its metabolites may be active. Despite being 96% bound to plasma proteins, it has few interactions with other drugs, and the 5-mg dose can be given safely to patients with mild-to-moderate hepatic and renal -disease. Side effects, which are mainly a consequence of its cholinomimetic mechanism of action, are usually mild and transient. Although donepezil was originally developed to inhibit the breakdown of the neurotransmitter acetylcholine as symptomatic therapy for AD, recent studies raise the possibility of other effects this drug has on the pathogenesis of AD.

Attitudes towards the diagnosis of Alzheimer's disease among carers and non-carers

This article provides some preliminary data on preferences among non-carer older adults regarding disclosure of Alzheimer's disease (AD) diagnosis, and compares these preferences to those of carers of people with AD (AD carers). Reasons underlying disclosure preference among carers and non-AD carers are investigated. The authors then explore the level of AD knowledge among carer and non-carer samples and investigate its relationship with disclosure preferences.

Participants were 20 elderly adults (aged 60–88 years) who were not caring for a relative with AD and 16 older adults (aged 51–79 years) who were caring for a relative with AD and who had attended a carer education programme. Participants completed a modified AD knowledge test and a test designed to measure the reasons for and against disclosure of an AD diagnosis.

AD knowledge among AD carers was significantly higher than that among non-carers. Views about disclosure of AD diagnoses did not differ between groups and generally, opinions were for disclosure. No significant differences were found when preferences for disclosure for oneself vs a significant other were compared. Similar reasons for disclosure were given by carers and non-carers, and included factors such as the person's right to know his or her diagnosis.

Donepezil in the treatment of dementia

Donepezil is an acetylcholinesterase inhibitor used to treat Alzheimer's disease. It has been shown to be effective in the treatment of cognitive symptoms, functional impairment and behavioral problems at mild, moderate and severe stages of the disease. Donepezil treatment results in modest short-term (6- to 9-month) improvement in some measures and attenuates the downward course of the disease for 1–3 years. Donepezil reaches peak plasma levels 3–4 h after ingestion and, with daily dosing, steady-state concentration in 14–21 days. The elimination half-life is approximately 70 h, and it is principally excreted unchanged in the urine. There is a linear relationship between plasma level and both red blood cell acetylcholinesterase inhibition and certain cognitive outcome measures. Donepezil is generally safe and well tolerated and, because of its dosing schedule, convenient to prescribe. Ongoing studies are examining the use of donepezil in combination with other drugs for Alzheimer's disease and for other conditions involving cognitive dysfunction.

Rivastigmine and donepezil treatment in moderate to moderately-severe Alzheimer's disease over a 2-year period

OBJECTIVES

Randomised controlled trials that directly compare cholinesterase inhibitors for the treatment of Alzheimer's disease have been characterised by significant methodological limitations. As a consequence, they have failed to establish whether there are differences between agents in this class. To help address this question, a double-blind, randomised, controlled, multicentre trial was designed to evaluate the efficacy and tolerability of cholinesterase inhibitor treatment in patients with moderate to moderately-severe Alzheimer's disease over a 2-year period.

METHODS

Patients were randomly assigned to rivastigmine 3-12 mg/day or donepezil 5-10 mg/day. Efficacy measures comprised assessments of cognition, activities of daily living, global functioning and behavioural symptoms. Safety and tolerability assessments included adverse events and measurement of vital signs.

RESULTS

In total, 994 patients received cholinesterase inhibitor treatment (rivastigmine, n = 495; donepezil, n = 499), and 57.9% of patients completed the study. The most frequent reason for premature discontinuation in both treatment groups was adverse events, primarily gastrointestinal. Adverse events were more frequent in the rivastigmine group during the titration phase, but similar in the maintenance phase. Serious adverse events were reported by 31.7% of rivastigmine- and 32.5% of donepezil-treated patients, respectively. Rivastigmine and donepezil had similar effects on measures of cognition and behaviour, but rivastigmine showed a statistically significant advantage on measures of activities of daily living and global functioning in the ITT-LOCF population. However, this was not maintained in the non-ITT-LOCF populations. In secondary subgroup analyses, AD patients who had genotypes that encoded for full expression of the butyrylcholinesterase enzyme (BuChE wt/wt; n = 226/340), who were < 75 years of age (n = 362/994) or who had symptoms suggestive of concomitant Lewy body disease (n = 49/994) showed significantly greater benefits from rivastigmine treatment.

CONCLUSIONS

Cholinesterase inhibitor treatment may offer continued therapeutic benefit for up to 2 years in patients with moderate AD. Although both drugs performed similarly on cognition and behaviour, rivastigmine may provide greater benefit in activities of daily living and global functioning.

Cognitive performance in patients with Alzheimer's disease receiving cholinesterase inhibitors for up to 5 years

The cholinesterase inhibitors (ChE-Is)--rivastigmine, donepezil and galantamine--demonstrated efficacy in large, 6-month, double-blind, placebo-controlled trials, and are widely used for the symptomatic treatment of patients with mild-to-moderate Alzheimer's disease (AD). Over the past few years, data have emerged, suggesting that these agents may have long-term benefits. These data have been summarized in this study, followed by an interpretation of clinical relevance. Data were identified by searches of Medline((R)) and references from relevant English-language articles. The search words 'Alzheimer', 'donepezil', 'rivastigmine', 'galantamine' and 'long term' were used. In addition, recent data presented at international congresses and/or provided by colleagues in this field of research were included in order to ensure maximum topicality. Data are available showing cognitive performance in patients remaining on rivastigmine for up to 5 years (n = 83), donepezil for up to 4.9 years (n = 18) and galantamine for up to 4 years (n = 185). Most of these data come from open-label studies and need to be interpreted with caution. The data appear to suggest that patients, caregivers and physicians will still see some decline on ChE-Is after a period of stabilization, but this may be slower and later than expected if the patients were left untreated. This applies across all domains of AD - not simply cognition - and function can be relatively preserved, even if cognitive scores are falling. Despite the limitations of current data, the information reviewed in this study may help practising doctors assess the long-term value of ChE-Is in this consistently progressive disease.

Effects of cholinesterase inhibitors appear greater in patients on established antihypertensive therapy

INTRODUCTION

There is increasing evidence that hypertension may contribute to development of dementia. Studies show that blood pressure lowering therapy might protect against cognitive deterioration and that antihypertensive treatment reduce the incidence of dementia.

AIM

We hypothesize that administration of cholinesterase inhibitors (AChEis) to patients with Alzheimer's Disease (AD) receiving antihypertensive medications therapy would result in clinical benefits for a period of 40 weeks in routine clinical practice.

METHODS AND MATERIALS

Patients with possible or probable AD were enrolled from 16 Alzheimer evaluation units (UVA) of Brescia and Cremona (Northern Italy). Patients treated with donepezil, rivastigmine and galantamine for 40 weeks independently of dosages were selected. Patients were evaluated at baseline (T0), 4 weeks (T1), 16 weeks (T2) and 40 weeks (T3).

RESULTS

416 patients completed the study at 40 weeks; of these 255 were 'non users' while 161 utilized antihypertensive drugs ('users'). The mean change in MMSE score from baseline to week 40 demonstrate that antihypertensive-treated patients improved by 0.7 points while patients receiving only AChEis remain stables. Analyzing separately patients (n = 183) that ameliorate (responders) on cognition at T3 ( >/= 1 point MMSE score increase) a significant differences in favor of 'users' antihypertensive drugs over 'non users' on cognition at weeks 16 and 40 has been demonstrated. In particular, at T2 the mean change of MMSE from baseline in 'users' was 3.2 +/- 2.6 vs 'non users' 2.2 +/- 2.3 ( p = 0.016) and at T3 was 3.5 +/- 2.5 vs 'non users' 2.0.2.7+/-1.6 ( p = 0.018). Antihypertensive drugs were independently associated with cognitive improvement in responder patients treated with AChEis (95% CI: 0.41-1.79; p = 0.002).

CONCLUSION

Antihypertensive medications in AD patients treated with AChEis are associated with an independent improvement on cognition after 40 weeks of treatment.

Symptomatic effect of donepezil, rivastigmine, galantamine and memantine on cognitive deficits in the APP23 model

RATIONALE

APP23 mice are a promising model of Alzheimer's disease, expressing several histopathological, cognitive and behavioural hallmarks of the human condition. A valid animal model should respond to therapeutic interventions in an equivalent manner as human patients.

OBJECTIVES

To further validate the APP23 model, we examined whether cognitive deficits could be antagonised by donepezil, rivastigmine, galantamine or memantine, which are approved drugs for symptomatic treatment of dementia.

METHODS

Animals were tested at an age at which untreated APP23 mice display severe deficits in visual-spatial learning. Four-month-old APP23 mice and control littermates were administered donepezil (0.3 or 0.6 mg kg(-1)), rivastigmine (0.5 or 1.0 mg kg(-1)), galantamine (1.25 or 2.5 mg kg(-1)), memantine (2 or 10 mg kg(-1)) or saline through daily i.p. injections. After 1 week of treatment, acquisition phase commenced, with daily treatment continuing during cognitive testing.

RESULTS

All cholinesterase inhibitors reduced cognitive deficits with the following optimal daily doses: galantamine 1.25 mg kg(-1), rivastigmine 0.5 mg kg(-1) and donepezil 0.3 mg kg(-1). Higher dosages often did not exert beneficial effects in accordance with inverted U-shaped dose-response curves described for cholinomimetics. Symptomatic efficacy of memantine on cognition was mild, with significant amelioration manifesting during probe trial.

CONCLUSIONS

This is the first study to simultaneously evaluate the efficacy of therapeutically relevant doses of these four compounds in one particular learning and memory paradigm, being the Morris water maze. The fact that symptomatic intervention was able to diminish cognitive impairment, substantially adds to the validity of the APP23 model as a valuable tool to evaluate future therapeutic approaches.

Results of a multi-level therapeutic approach for Alzheimer's disease subjects in the "real world" (CRONOS project): a 36-week follow-up study

BACKGROUND AND AIMS

Recently, the Italian Ministry of Health started a national project (CRONOS project), aiming at assessing how a multi-level therapeutic approach--including 2-year free-of-charge treatment with cholinesterase inhibitors (ChE-I), pharmacologic and non-pharmacologic management of behavioral disorders, periodic multi-dimensional assessment, and informal caregivers' counseling-performs in subjects with mild-to-moderate Alzheimer's disease (AD). Five hundred and three Alzheimer Evaluation Units (AEUs) were instituted for this purpose all over Italy. In this paper we present the results of this approach in a large population of AD subjects followed for 36 weeks by 14 AEUs in Eastern Lombardy, Italy.

METHODS

The project lasted for two years (September 2000-September 2002). Subjects eligible for the CRONOS project had a diagnosis of probable AD, a Mini Mental State Examination (MMSE) score at baseline ranging from 10 to 26, and onset of cognitive disorders between 40 and 90 years of age. Periodic clinical and multi-dimensional assessments, including MMSE, Activities of Daily Living (ADL) and Instrumental Activities of Daily Living (IADL) were made at 12 and 36 weeks; ChE-I doses, psychotropic and antidepressant drugs were also re-assessed at all clinical examinations. Caregivers were instructed about dementia and drug-related problems.

RESULTS

Of the 808 subjects who completed the 36-week follow-up, 441 were naïves (i.e., never previously treated with ChE-I drugs) and 367 non-naïves. At 12 weeks, both naïves (mean variation from baseline = 0.8 points) and non-naïves (mean variation from baseline = 0.5 points) improved their MMSE scores, while at 36 weeks only naïves improved (mean variation from baseline = 0.1) and non-naïves decreased (mean variation from baseline = -1.2). The IADL and ADL scores progressively and mildly declined from baseline to the 36th week (ADL, mean variation from baseline = -0.5 for naïves, -0.3 for non-naïves; IADL = -0.7 for naïves, mean variation from baseline = -0.4). However, when the MMSE, ADL and IADL variations were controlled for age, sex and education, no significant time effect was found (MMSE, Wilks' lambda p = 0.34; ADL, Wilks' lambda p = 0.25; IADL, Wilks' lambda p = 0.3, respectively). These patterns were apparently unrelated to ChE-I doses. Neuroleptic use doubled in naïves and antidepressants increased in both groups.

CONCLUSIONS

This multi-level therapeutic approach seems to slow down progression in cognitive and functional performance, in both naïve and non-naïve subjects. The possibility of recurrent examinations by specialized physicians, accurate, lose management of psychotropic drugs, and informal counseling to caregivers probably aid in achieving such results in a "real world" population of AD elderly subjects living at home. Future studies are needed to assess whether a multi-level therapeutic approach including higher ChE-I dose may perform better in these subjects.

Issues for Clinical Drug Development in Neurodegenerative Diseases

Neurodegenerative diseases pose specific challenges for drug development. These diseases typically have a slow and variable clinical course, an insidious onset, and symptom expression is only observed when a significant proportion of neurons are already lost. It is important to identify vulnerability factors and other determinants of clinical course in order to be able in the future to select patient populations for clinical trials with a predictable prognosis. The neurodegenerative process itself is not amenable to direct observation and, thus, cannot be monitored in clinical trials. For this reason, surrogate biomarkers are required for use as outcome parameters. In this respect, magnetic resonance imaging has proved valuable for assessing disease activity and progression in multiple sclerosis. Rating scales are of use as outcome measures but, as these generally measure symptom severity, they are most appropriate for use in assessing symptomatic treatments. Survival has been used with success as an outcome measure in trials in amyotrophic lateral sclerosis, where disease progression is rapid. The optimal outcome measure, the sample size required and the treatment duration need to be chosen in relation to the phase of the disease. Potential new treatments can be chosen based upon new knowledge of the genetics and physiopathology of neurodegenerative diseases and, in some cases, screened in transgenic mouse models, although it should be recognised that the validity of these models in terms of treatment response has yet to be established empirically.

Guidelines for the Treatment of Alzheimer??s Disease from the Italian Association of Psychogeriatrics

A committee of experts from the Italian Association of Psychogeriatrics compiled the following report, which was then approved by a Steering Committee (comprising 20 specialists in neurology, psychiatry or geriatrics) from the Association and by two Alzheimer associations representing patients and families: the Italian Association for Alzheimer's Disease and the Italian Federation for Alzheimer's Disease. The report is based on a comprehensive review of the scientific literature on the treatment of Alzheimer's disease, discusses methodological aspects of dementia management, and details the limitations of current therapies. These guidelines are, in general, consistent with the principles of evidence-based medicine; however, for some controversial or poorly investigated issues, the guidelines integrate scientific evidence with experience and opinions from experts working in the clinical setting. In particular, the clinical experience of experts has been used to define recommendations for starting and interrupting pharmacotherapy, and to critically review evidence about the efficacy of non-pharmacological interventions. The principal pharmacotherapeutic interventions covered in the guidelines are acetylcholinesterase inhibitors (donepezil, galantamine, rivastigmine, and tacrine) and memantine. The main non-pharmacological interventions reviewed are memory training, reality orientation therapy, and combined non-pharmacological interventions. Other issues covered are opportunities for Alzheimer's disease prevention, various modalities of care, and the treatment of comorbidities.

Cholinesterase inhibitors used in the treatment of Alzheimer's disease: the relationship between pharmacological effects and clinical efficacy

The deficiency in cholinergic neurotransmission in Alzheimer's disease has led to the development of cholinesterase inhibitors as the first-line treatment for symptoms of this disease. The clinical benefits of these agents include improvements, stabilisation or less than expected decline in cognition, function and behaviour. The common mechanism of action underlying this class of agents is an increase in available acetylcholine through inhibition of the catabolic enzyme, acetylcholinesterase. There is substantial evidence that the cholinesterase inhibitors, including donepezil, galantamine and rivastigmine, decrease acetylcholinesterase activity in a number of brain regions in patients with Alzheimer's disease. There is also a significant correlation between acetylcholinesterase inhibition and observed cognitive improvement. However, the cholinesterase inhibitors are reported to have additional pharmacological actions. Rivastigmine inhibits butyrylcholinesterase with a similar affinity to acetylcholinesterase, although it is not clear whether the inhibition of butyrylcholinesterase contributes to the therapeutic effect of rivastigmine. Based on data from preclinical studies, it has been proposed that galantamine also potentiates the action of acetylcholine on nicotinic receptors via allosteric modulation; however, the effects appear to be highly dependent on the concentrations of agonist and galantamine. It is not yet clear whether these concentrations are related to those achieved in the brain of patients with Alzheimer's disease within therapeutic dose ranges. Preclinical studies have shown that donepezil and galantamine also significantly increase nicotinic receptor density, and increased receptor density may be associated with enhanced synaptic strengthening through long-term potentiation, which is related to cognitive function. Despite these differences in pharmacology, a review of clinical data, including head-to-head studies, has not demonstrated differences in efficacy, although they may have an impact on tolerability. It seems clear that whatever the subsidiary modes of action, clinical evidence supporting acetylcholinesterase inhibition as the mechanism by which cholinesterase inhibitors treat the symptoms of Alzheimer's disease is accumulating. Certainly, as a class, the currently approved cholinesterase inhibitors (donepezil, galantamine, rivastigmine and tacrine) provide important benefits in patients with Alzheimer's disease and these drugs offer a significant advance in the management of dementia.

Association of a salivary acetylcholinesterase with Alzheimer's disease and response to cholinesterase inhibitors

OBJECTIVES

A decrease in cholinergic activity is a key event in the biochemistry of Alzheimer's disease (AD). The aim of the study was to investigate the expression levels of markers of cholinergic function in saliva, which is a readily accessible body fluid that can be obtained from subjects with minimal distress.

DESIGN AND METHODS

Salivary samples were obtained from people with NINCDS-ARDRA "probable" Alzheimer's disease and age- and sex-matched controls. Salivary acetylcholinesterase enzyme (AChE) activity was determined colorometrically.

RESULTS

Robust AChE catalytic activity was detected in the saliva samples that was stable for up to 6 h at room temperature following the provision of the salivary sample. The activity of the enzyme was significantly lower in people with AD than in age-matched controls. In addition, there were significant differences in activity between those who responded to acetylcholinesterase inhibitor (AChE-I) therapy and those who did not.

CONCLUSIONS

Salivary enzyme activity may therefore prove to be a useful marker of central cholinergic activity.

Cerebral Perfusional Effects of Cholinesterase Inhibitors in Alzheimer Disease

Cholinesterase (ChE) inhibitors improve or stabilize cognitive impairment in patients with Alzheimer disease (AD). However, the regional metabolic and perfusion correlates of treatment with ChE inhibitors are not fully known. Twenty-four patients with mild to moderate AD were evaluated with Tc-ethyl cysteinate dimer (ECD) single-photon-emission CT scanning (SPECT), before and after 4.3 +/- 1.1 months of treatment with ChE inhibitors (donepezil, rivastigmine). Clinical evaluations included the Mini-Mental State Examination (MMSE) as well as the Neuropsychiatric Inventory (NPI). Inclusion criterion was a clear favorable response to therapy with ChE inhibitors (MMSE improvement of at least 2 points; total NPI improvement of at least 4 points). SPECT data were analyzed by Statistical Parametric Mapping (SPM 99, Wellcome, Department of Cognitive Neurology, London, UK). SPM analysis showed a significant increase (P < 0.01) of regional cerebral perfusion (rCBF) after short-term ChE inhibitor therapy with respect to baseline in the right anterior cingulate, the dorsolateral prefrontal, and the temporoparietal areas bilaterally. These data suggest that cognitive or behavioral benefits after ChE inhibitor therapy are related to a clear increase of rCBF in crucial areas specifically involved in the attentional and limbic networks.

Practical Principles for the Management of Alzheimer's Disease

Alzheimer's disease is a complex disorder that is particularly challenging to treat and manage. Early recognition of Alzheimer's disease is the first step toward providing patients with optimal therapy and the best opportunity for treatment response. Subsequently, physicians will need to address issues that emerge as the disease inevitably progresses. As the number of elderly patients with Alzheimer's disease increases, it becomes increasingly important for the primary care physician-usually the first line of patient contact-to diagnose Alzheimer's disease early, and initiate and manage appropriate long-term cholinesterase inhibitor therapy, which has been shown to provide significant benefits to Alzheimer's disease patients. In this article, discussions of individual patients illustrate commonly encountered situations in the primary care setting.

The cost-benefit of cholinesterase inhibitors in mild to moderate dementia: a willingness-to-pay approach

OBJECTIVE

This study aimed to measure the economic value of cholinesterase inhibitors when used to treat Alzheimer's disease using the willingness-to-pay (WTP) approach and the framework of cost-benefit analysis.

METHODS AND STUDY DESIGN

A cost-benefit analysis using the WTP approach was employed. The study sample consisted of 28 nonprofessional caregivers of outpatients with mild to moderate dementia from Toronto, ON, Canada. The caregivers were presented with four scenarios. In the first scenario, scenario A, a hypothetical patient with mild dementia was stabilised with a cholinesterase inhibitor. In the second scenario, scenario A with adverse effects, the above patient (A) experienced adverse effects caused by the drug. In the third scenario, scenario B, the patient exhibited behavioural symptoms in addition to mild dementia, and both were stabilised with the drug. In the fourth scenario, scenario B with adverse effects, the above patient (B) experienced adverse effects caused by the drug. The caregivers were then asked what amount they would pay, in Canadian dollars, each year to buy the medication, assuming that they were the caregivers of the patient described. A multivariate regression analysis was performed to assess the relationship between the demographic data (including the caregiver's yearly income) and the WTP. The average WTP was also predicted for the general population and the elderly population of Canada using data from Statistics Canada, and these values were compared with the cost of the medication.

STUDY PERSPECTIVE

Nonprofessional caregiver perspective. All monetary values are 1999 values unless otherwise specified.

RESULTS

The mean yearly WTP was $Can4540 (95% CI 2334-6746) for scenario A, $Can3686 (95% CI 1530-5842) for scenario A with adverse effects, $Can5003 (95% CI 2661-7345) for scenario B and $Can4486 (95% CI 2222-6750) for scenario B with adverse effects. The WTP decreased when drug adverse effects were present (significantly in scenario A; p = 0.04), but did not significantly increase when behavioural symptoms were present and stabilised. In all scenarios, caregiver yearly income was the only significant predictor of WTP, in the direction expected. For all scenarios, the calculated WTPs from the regression analysis using our sample mean, the average Canadian population data and the elderly population data were all higher than the yearly cost of the cholinesterase inhibitors, with the net benefit ranging from $Can1723 to $Can4508.

CONCLUSIONS

The results of the study, from a small sample of nonprofessional caregivers, revealed that the caregivers are willing to pay more for cholinesterase inhibitors than the drugs cost, even when the adverse effects of the drugs are taken into consideration. This indicates a net benefit for cholinesterase inhibitors in the treatment of mild to moderate dementia from a consumer's point of view.

Long-Term Treatment of Alzheimer Disease

During the past 20 years, research on Alzheimer disease (AD) and other dementias has increased our understanding of these disorders and has opened doors to new methods of treatment. Acetylcholinesterase inhibitors (AChEIs) have been successful in reducing symptoms in patients with mild-to-moderate AD and led to the US Food and Drug Administration's approval of four AChEIs for the treatment of AD. Although these agents are approved for only mild-to-moderate AD, and the available data for most of them are from trials of only 6 months' duration, long-term studies suggest that the benefits of AChEI treatment can endure for up to 4 years. A common pattern of response to treatment is initial improvement in cognition, followed by maintenance of cognitive gains above baseline for up to 1 year. Generally there is a decline in cognition to below baseline levels after approximately 1 year of treatment, but the level of cognition remains above that predicted for those not receiving pharmacologic treatment. Furthermore, long-term studies suggest that early diagnosis and treatment with AChEIs yield better long-term outcomes. Patients who received continuous pharmacologic treatment from the outset generally had better long-term outcomes than those who received placebo in the double-blind phase of these trials.

Rational choice of cholinesterase inhibitor for the treatment of Alzheimer's disease in Canada: a comparative economic analysis

BACKGROUND

Cholinesterase inhibitors, such as galantamine, donepezil and rivastigmine are approved for symptomatic treatment of Alzheimer's Disease (AD) in Canada. In making choices amongst these drugs, one should consider their clinical merits and their economic implications.

METHODS

Each drug's short-term efficacy was estimated based on independent Cochrane reviews of the clinical trials. Long-term clinical and economic outcomes were estimated using the Assessment of Health Economics in Alzheimer's Disease (AHEAD) model.

RESULTS

While all treatments reduced the need for full-time care, only galantamine and donepezil 10 mg reduced the overall management costs of AD patients. The somewhat greater cognitive effect provided over six months by galantamine leads to the longest estimated delay before full-time care is required and, consequently to lower overall costs, with savings estimated at between 323 dollars and 4,246 dollars.

CONCLUSION

Although there is uncertainty in estimated results, the best information currently available suggests that the first choice for treatment of AD should be galantamine. These results should be interpreted with caution, however, as results are not based on direct comparisons among the drugs and the differences emerging from meta-analyses of the trials are relatively small.

Long-Term Cholinesterase Inhibitor Therapy for Alzheimer's Disease: Practical Considerations for the Primary Care Physician

BACKGROUND: With the aging of the population, primary care physicians are increasingly expected to manage patients with Alzheimer's disease. For patients with this disease to obtain the best outcomes over the long term, early diagnosis and effective treatment are critical. Currently, cholinesterase inhibitors are the only drugs approved in the United States for the treatment of mild-to-moderate Alzheimer's disease. METHOD: Relevant clinical studies were identified through a search of the MEDLINE database using the terms Alzheimer's disease and donepezil, galantamine, or rivastigmine, using the limits of English language and publication dates of 1995 to 2003. Published studies were selected that provided information on the long-term use, defined as 1 year or longer, of second-generation cholinesterase inhibitors approved by the U.S. Food and Drug Administration for the treatment of mild-to-moderate Alzheimer's disease. RESULTS: 590 references were identified. Of these, 11 studies met the final study criteria, and 10 were selected (1 of the 11 was an interim analysis). CONCLUSIONS: The benefits of sustained long-term treatment with cholinesterase inhibitors have been demonstrated over the last several years. By reducing cognitive and functional decline over time, long-term cholinesterase inhibitor therapy enables patients to stay at home longer and may decrease the burdens faced by patients, caregivers, and society.

Memantine (Ebixa®) in the later stages of dementia

Memantine is the first agent licensed for the treatment of moderate to severe Alzheimer's disease. It is an N-methyl D-aspartate (NMDA) receptor antagonist which reduces glutamatergic excitotoxicity. Benefits are seen in cognitive, functional and global measures in both outpatients and nursing home residents. Prospective health economic benefits have been reported.

Update on Alzheimer drugs (donepezil)

BACKGROUND

Several clinical trials have been conducted over a period of many years reporting the benefits of donepezil for Alzheimer disease (AD) patients.

REVIEW SUMMARY

Randomized, double-blind, placebo-controlled stud-ies of 3-6 months' duration have demonstrated significant benefits for 5mg/D and 10 mg/D of donepezil compared with placebo. The results include benefits for cognition, activities of daily living, and abnormal behaviors associated with AD. The benefits are independently detectable by clinicians based upon direct patient assessment with input from a caregiver. Populations studied include mild-to-moderate AD patients, moderate-to-severe AD patients, nursing home patients, and outpatients. Open label studies that took place after the double-blind phase and 1-year double-blind, placebo-controlled trials demonstrated that benefits persist for more than a year. Adverse event (AE) profiles, generated in studies that used a 1-week forced dose titration, show a low incidence of primarily cholinegic AEs such as nausea and diarrhea. There are no significant laboratory AEs or drug interactions. Recent studies have assessed the benefits of donepezil inpatients with ischemic vascular dementia, mild cognitive impairment, and other cognitive disorders.

CONCLUSIONS

Donepezil benefits AD patients by improving, stabilizing, or retarding decline of the cognitive, functional, and possibly behavioral features of the disease. The duration of benefits is not known but extends beyond 1 year. The drug is safe and well tolerated.

Donepezil is associated with delayed nursing home placement in patients with Alzheimer's disease

OBJECTIVES

To assess the relationship between donepezil treatment and time to nursing home placement (NHP) for patients with Alzheimer's disease (AD).

DESIGN

Observational follow-up of patient NHP and vital status.

SETTING

Community.

PARTICIPANTS

Patients previously enrolled in one of three randomized, double-blind, placebo-controlled clinical trials of donepezil and two subsequent open-label studies (total N = 1,115); 671 patients provided complete data for analysis.

MEASUREMENTS

Data were obtained through follow-up interviews with caregivers and chart reviews of patients with AD. Comparison groups were defined by whether patients received an effective dose of donepezil (>/=5 mg/d; >/=80% compliance) for specific numbers of weeks during the double-blind or open-label trial phase, in both phases, or in neither. Cox proportional hazards models were used to estimate risk ratios for NHP and survival curves from which median times to NHP were estimated for first dementia-related placement of longer than 2 weeks and permanent placement. The models were adjusted for age, sex, baseline Mini-Mental State Examination score, whether the caregiver was a spouse, caregiver continuity, and use of other cholinesterase inhibitors after the clinical trials.

RESULTS

Use of donepezil of 5 mg/d or more was associated with significant delays in NHP. A cumulative dose-response relationship was observed between longer-term sustained donepezil use and delay of NHP. When donepezil was taken at an effective dose for at least 9 to 12 months, conservative estimates of the time gained before NHP were 21.4 months for first dementia-related NHP and 17.5 months for permanent NHP.

CONCLUSION

Use of donepezil by AD patients resulted in significant delays in NHP. Long-term use of donepezil may help AD patients live longer in community settings, with consequent personal, social, and economic benefits.

Clinically tested drugs for Alzheimer's disease

Alzheimer's disease poses a major health problem in developed countries and vigorous research is underway aimed at finding effective treatments. Acetylcholinesterase inhibitors are approved but give only temporary cognitive benefit to a percentage of patients. Their relative ineffectiveness is not surprising since the neuronal loss comprises much more than the forebrain cholinergic system. What is needed is a drug that will halt the neuronal death and thus progression of the disease. Avenues being explored are aimed at pathological features of the disease, i.e., drugs aimed at removing the amyloid burden which forms the plaques or reducing the neurotoxic neuroinflammation and oxidative stress which characterise the diseased brain regions. There are some promising leads, but more definitive clinical trials are required. Any agent designed to slow progression should clearly be used at an early stage of the disorder; therefore methods of early diagnosis are also essential.

Long-term cholinesterase inhibitor therapy for Alzheimer's disease: implications for long-term care

As the population ages and Alzheimer's disease (AD) becomes more prevalent, nursing facilities will be faced with managing more AD patients than in previous decades. Managing this population will pose a significant challenge for the resources of long-term care facilities. In short- and long-term studies, cholinesterase (ChE) inhibitor treatment has been shown to benefit the symptoms of mild to moderate AD. Donepezil trials have extended this finding to patients with moderate to severe AD as well as the more severe symptoms of AD patients residing in nursing home settings. Results from long-term ChE inhibitor trials and the benefits that may be gained by treating AD patients residing in nursing facilities are presented.

Current pharmacologic options for patients with Alzheimer's disease

BACKGROUND: The aim of the current study was to provide general practitioners with an overview of the available treatment options for Alzheimer's disease (AD). Since general practitioners provide the majority of medical care for AD patients, they should be well versed in treatment options that can improve function and slow the progression of symptoms. DESIGN: Biomedical literature related to acetylcholinesterase inhibitors (AChEIs) was surveyed. In the United States, there are four AChEIs approved for the treatment of AD: tacrine, donepezil, rivastigmine, and galantamine. There are other agents under investigation, but at present, AChEIs are the only approved drug category for AD treatment. MEASUREMENTS AND MAIN RESULTS: AD is becoming a major public health concern and underdiagnosis is a significant problem (with only about half of AD patients being diagnosed and only half of those diagnosed actually being treated). Clinical trials have demonstrated that patients with AD who do not receive active treatment decline at more rapid rates than those who do. CONCLUSIONS: Given that untreated AD patients show decline in three major areas (cognition, behavior, and functional ability), if drug treatment is able to improve performance, maintain baseline performance over the long term, or allow for a slower rate of decline in performance, each of these outcomes should be viewed a treatment success.

Donepezil for dementia due to Alzheimer's disease

BACKGROUND

Alzheimer's disease is the most common cause of dementia in older people. One of the aims of therapy is to inhibit the breakdown of a chemical neurotransmitter, acetylcholine, by blocking the relevant enzyme. This can be done by a group of chemicals known as cholinesterase inhibitors. However, some (like tacrine) are associated with adverse effects such as hepatotoxicity, but donepezil (E2020, Aricept) is safer.

OBJECTIVES

The objective of this review is to assess whether donepezil improves the well-being of patients with dementia due to Alzheimer's disease.

SEARCH STRATEGY

The Cochrane Dementia and Cognitive Improvement Group's Specialized Register was searched using the terms 'donepezil', 'E2020' and 'Aricept' on 9 October 2002. This Register contains up-to-date records of all major health care databases and many ongoing trial databases. Members of the Donepezil Study Group and Eisai Inc were contacted.

SELECTION CRITERIA

All unconfounded, double-blind, randomized controlled trials in which treatment with donepezil was compared with placebo for patients with mild, moderate or severe dementia due to Alzheimer's disease.

DATA COLLECTION AND ANALYSIS

Data were extracted by one reviewer (JSB ), pooled where appropriate and possible, and the weighted mean differences or Peto odds ratios (95%CI) estimated.

MAIN RESULTS

Sixteen trials are included, involving 4365 participants. The trials were of 12, 24 or 52 weeks duration in selected patients. Available outcome data cover domains including cognitive function and global clinical state, but data on several important dimensions of outcome are unavailable. For cognition there is a statistically significant improvement for both 5 and 10 mg/day of donepezil at 24 weeks compared with placebo (-2.02 points on the ADAS-Cog scale WMD, 95%CI -2.77 to -1.26, p<0.00001; -2.92 points on the ADAS-Cog scale WMD 95% CI -3.74 to -2.10, p<0.00001)and for 10 mg/day donepezil compared with placebo at 52 weeks (1.84MMSE points, 95% CI, 0.53 to3.15, p=0.006). The results show some improvement in global clinical state (assessed by an independent clinician) in people treated with 5 and 10 mg/day of donepezil compared with placebo at 12 and 24 weeks. Benefits of treatment were also seen on measures of activities of daily living and behaviour. There were significantly more withdrawals before the end of treatment from the 10 mg/day (but not the 5 mg/day) donepezil group compared with placebo which may have resulted in some overestimation of beneficial changes at 10 mg/day.A variety of adverse effects were recorded, with more incidents of nausea, vomiting, diarrhoea and anorexia in the 10 mg/day group compared with placebo and the 5 mg/day group, but very few patients left a trial as a direct result of the intervention.

REVIEWER'S CONCLUSIONS

People with mild, moderate or severe dementia due to Alzheimer's disease treated for periods of 12, 24 or 52 weeks with donepezil experienced benefits in cognitive function, activities of daily living and behaviour. Study clinicians rated global clinical state more positively in treated patients, and measured less decline in measures of global disease severity. Although no significant changes were measured on a patient-rated quality of life scales, the instrument used was crude and possibly unsuited to the task. The additional data now available confirm the findings of the previous issue of this review and extend the evidence for the effectiveness of treatment to at least 52 weeks and to those with severe dementia. More evidence is still needed for the economic efficacy of donepezil, but clinical efficacy is confirmed.

Beneficial effect of donepezil augmentation for the management of comorbid schizophrenia and dementia

Comorbid schizophrenia and dementia is a common clinical phenomenon; however, management of the coexisting illnesses remains incomplete. Donepezil, a cholinesterase inhibitor, may be beneficial for the management of symptoms of Alzheimer's disease, a disease in which cholinergic pathways in the cerebral cortex and basal forebrain are well known to be compromised. Furthermore, impaired cognition in elderly schizophrenic patients has been observed to be more than two thirds; however, there are no published controlled studies reporting the use of cholinesterase inhibitors in the management of schizophrenia in patients with associated dementia. In this study, six patients with chronic schizophrenia and comorbid dementia were administered donepezil, 5 mg, in single-blind fashion as augmentation to their standard antipsychotic medication for a 4-week period. Patients were evaluated with the Mini Mental State Examination (MMSE); Alzheimer's Disease Assessment Scale, Cognitive subscale; Positive and Negative Symptom Scale (PANSS); and the Clinical Global Impression (CGI) scales. A significant improvement was noted in MMSE scores (P < 0.01) and for CGI scores (P < 0.01). In addition, three patients demonstrated improvement on the PANSS. Donepezil appears to be an effective treatment for the management of symptoms of dementia accompanying patients with comorbid schizophrenia and dementia. Since cholinergic dysfunction may be present in some patients with schizophrenia, the authors' findings further demonstrate the possibility that this disorder may be managed with cholinergic medications as augmenting agents, at least in this specific subpopulation of patients with comorbid dementia. To confirm the findings of this preliminary trial, further investigation is mandated with a larger sample of subjects in the context of a double-blind medication trial.

Progress in clinical neurosciences: Treatment of Alzheimer's disease and other dementias--review and comparison of the cholinesterase inhibitors

BACKGROUND

Alzheimer's disease (AD) is the most common cause of dementia in older adults. Acceptance of the cholinergic hypothesis led to a search for medications which could enhance central cholinergic activity in this condition. There are now three cholinesterase inhibitors available for the treatment of AD in Canada.

OBJECTIVES

To review the currently available cholinesterase inhibitors approved for the treatment of AD in Canada and to provide guidance on who and how to treat with these agents.

RESULTS

Donepezil, rivastigmine, and galantamine are approved for the treatment of AD in Canada. In clinical trails, patients with mild to moderate AD treated with these agents experienced modest improvements in cognition, function, behaviour, and/or global clinical state. The magnitude of benefits seen with each agent appeared to be similar. While to date, there is no convincing evidence that one is more efficacious or effective, they do differ in their pharmacokinetics, additional mechanisms of action, and side effect profiles. Therefore, the selection of agent will be based on considerations such as side effect profiles, ease of administration, personal familiarity/experience, and beliefs about the importance of the noted differences in their pharmacokinetics and additional mechanisms of action.

CONCLUSION

We believe that these agents should be offered to all individuals with a mild to moderate dementia where Alzheimer's pathology is felt to be a contributing factor. We view all three available cholinesterase inhibitors as first-line drugs.