Donepezil treatment in severe Alzheimer's disease: a pooled analysis of three clinical trials

Differential response to donepezil in MRI subtypes of mild cognitive impairment

BACKGROUND

Donepezil is an approved therapy for the treatment of Alzheimer's disease (AD). Results across clinical trials have been inconsistent, which may be explained by design-methodological issues, the pathophysiological heterogeneity of AD, and diversity of included study participants. We investigated whether response to donepezil differs in mild cognitive impaired (MCI) individuals demonstrating different magnetic resonance imaging (MRI) subtypes.

METHODS

From the Hippocampus Study double-blind, randomized clinical trial, we included 173 MCI individuals (donepezil = 83; placebo = 90) with structural MRI data, at baseline and at clinical follow-up assessments (6-12-month). Efficacy outcomes were the annualized percentage change (APC) in hippocampal, ventricular, and total grey matter volumes, as well as in the AD cortical thickness signature. Participants were classified into MRI subtypes as typical AD, limbic-predominant, hippocampal-sparing, or minimal atrophy at baseline. We primarily applied a subtyping approach based on continuous scale of two subtyping dimensions. We also used the conventional categorical subtyping approach for comparison.

RESULTS

Donepezil-treated MCI individuals showed slower atrophy rates compared to the placebo group, but only if they belonged to the minimal atrophy or hippocampal-sparing subtypes. Importantly, only the continuous subtyping approach, but not the conventional categorical approach, captured this differential response.

CONCLUSIONS

Our data suggest that individuals with MCI, with hippocampal-sparing or minimal atrophy subtype, may have improved benefit from donepezil, as compared with MCI individuals with typical or limbic-predominant patterns of atrophy. The newly proposed continuous subtyping approach may have advantages compared to the conventional categorical approach. Future research is warranted to demonstrate the potential of subtype stratification for disease prognosis and response to treatment.

TRIAL REGISTRATION

ClinicalTrial.gov NCT00403520. Submission Date: November 21, 2006.

Long-term Effects of Cholinesterase Inhibitors on Cognitive Decline and Mortality

Objective

To investigate whether cholinesterase inhibitors (ChEIs) are associated with slower cognitive decline in Alzheimer dementia and decreased risk of severe dementia or death.

Methods

Patients with Alzheimer dementia from the Swedish Dementia Registry starting on ChEIs within 3 months of the dementia diagnosis were included and compared to nontreated patients with Alzheimer dementia. In a propensity score–matched cohort, the association between ChEI use and cognitive trajectories assessed by Mini-Mental State Examination (MMSE) scores was examined with a mixed model, and severe dementia (MMSE score <10) or death as an outcome was assessed with Cox proportional hazards models.

Results

The matched cohort included 11,652 ChEI users and 5,826 nonusers. During an average of 5 years of follow-up, 255 cases developed severe dementia, and 6,055 (35%) died. ChEI use was associated with higher MMSE score at each visit (0.13 MMSE points per year; 95% confidence interval [CI] 0.06–0.20). ChEI users had a 27% lower risk of death (0.73, 95% CI 0.69–0.77) compared with nonusers. Galantamine was associated with lower risk of death (0.71, 95% CI 0.65–0.76) and lower risk of severe dementia (0.69, 95% CI 0.47–1.00) and had the strongest effect on cognitive decline of all the ChEIs (0.18 MMSE points per year, 95% CI 0.07–0.28).

Conclusions

ChEIs are associated with cognitive benefits that are modest but persist over time and with reduced mortality risk, which could be explained partly by their cognitive effects. Galantamine was the only ChEI demonstrating a significant reduction in the risk of developing severe dementia.

Classification of Evidence

This study provides Class III evidence that for patients with Alzheimer dementia ChEIs decrease long-term cognitive decline and risk of death and that galantamine decreases the risk of severe dementia.

Assessment of Demographic, Genetic, and Imaging Variables Associated With Brain Resilience and Cognitive Resilience to Pathological Tau in Patients With Alzheimer Disease

Question

Which demographic, genetic, and neuroimaging factors are associated with cognitive and brain resilience to pathological tau in patients with Alzheimer disease?

Findings

In this multicenter, cross-sectional, longitudinal study of 260 cognitively impaired amyloid-β–positive participants, young age and female sex were associated with greater brain resilience, whereas higher educational level and cortical thickness were associated with greater cognitive resilience.

Meaning

Cognitive and brain resilience may be associated with differential mechanisms, which may help explain interindividual differences in how well patients tolerate pathological tau.

Importance

Better understanding is needed of the degree to which individuals tolerate Alzheimer disease (AD)–like pathological tau with respect to brain structure (brain resilience) and cognition (cognitive resilience).

Objective

To examine the demographic (age, sex, and educational level), genetic (APOE-ε4 status), and neuroimaging (white matter hyperintensities and cortical thickness) factors associated with interindividual differences in brain and cognitive resilience to tau positron emission tomography (PET) load and to changes in global cognition over time.

Design, Setting, an Participants

In this cross-sectional, longitudinal study, tau PET was performed from June 1, 2014, to November 30, 2017, and global cognition monitored for a mean [SD] interval of 2.0 [1.8] years at 3 dementia centers in South Korea, Sweden, and the United States. The study included amyloid-β–positive participants with mild cognitive impairment or AD dementia. Data analysis was performed from October 26, 2018, to December 11, 2019.

Exposures

Standard dementia screening, cognitive testing, brain magnetic resonance imaging, amyloid-β PET and cerebrospinal fluid analysis, and flortaucipir (tau) labeled with fluor-18 (¹⁸F) PET.

Main Outcomes and Measures

Separate linear regression models were performed between whole cortex [¹⁸F]flortaucipir uptake and cortical thickness, and standardized residuals were used to obtain a measure of brain resilience. The same procedure was performed for whole cortex [¹⁸F]flortaucipir uptake vs Mini-Mental State Examination (MMSE) as a measure of cognitive resilience. Bivariate and multivariable linear regression models were conducted with age, sex, educational level, APOE-ε4 status, white matter hyperintensity volumes, and cortical thickness as independent variables and brain and cognitive resilience measures as dependent variables. Linear mixed models were performed to examine whether changes in MMSE scores over time differed as a function of a combined brain and cognitive resilience variable.

Results

A total of 260 participants (145 [55.8%] female; mean [SD] age, 69.2 [9.5] years; mean [SD] MMSE score, 21.9 [5.5]) were included in the study. In multivariable models, women (standardized β = −0.15, P = .02) and young patients (standardized β = −0.20, P = .006) had greater brain resilience to pathological tau. Higher educational level (standardized β = 0.23, P < .001) and global cortical thickness (standardized β = 0.23, P < .001) were associated with greater cognitive resilience to pathological tau. Linear mixed models indicated a significant interaction of brain resilience × cognitive resilience × time on MMSE (β [SE] = −0.235 [0.111], P = .03), with steepest slopes for individuals with both low brain and cognitive resilience.

Conclusions and Relevance

Results of this study suggest that women and young patients with AD have relative preservation of brain structure when exposed to neocortical pathological tau. Interindividual differences in resilience to pathological tau may be important to disease progression because participants with both low brain and cognitive resilience had the most rapid cognitive decline over time.

What works and what does not work in Alzheimer's disease? From interventions on risk factors to anti-amyloid trials

Alzheimer's disease (AD) is a progressive neurodegenerative disorder with no approved disease-modifying therapy (DMT). In this review, we summarize the various past approaches taken in an attempt to find treatments capable of altering the long-term course for individuals with AD, including: translating epidemiological observations into potential treatment options; seeking a single-treatment approach across the continuum of AD severity; utilizing biomarkers for assessing target engagement; using biomarkers as early surrogates of clinical efficacy; and enriching study populations to demonstrate adequate placebo decline during the limited duration of clinical trials. Although targeting the amyloid-β (Aβ) pathway has been central to the search for an effective DMT, to date, trials of anti-Aβ monoclonal antibodies have failed to consistently demonstrate significant clinical efficacy. Key learnings from these anti-Aβ trials, as well as the trials that came before them, have shifted the focus within clinical development programs to identifying target populations thought most likely to benefit from treatments (i.e., individuals at an earlier stage of disease). Other learnings include strategies to increase the likelihood of showing measurable improvements within the clinical trial setting by better predicting decline in placebo participants, as well as developing measures to quantify the needed treatment exposure (e.g., higher doses). Given the complexity associated with AD pathology and progression, treatments targeting non-amyloid AD pathologies in combination with anti-amyloid therapies may offer an alternative for the successful development of DMTs.

Cognitive symptoms of Alzheimer's disease: clinical management and prevention

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by the accumulation of amyloid β in the form of extracellular plaques and by intracellular neurofibrillary tangles, with eventual neurodegeneration and dementia. There is currently no disease-modifying treatment though several symptomatic medications exist with modest benefit on cognition. Acetylcholinesterase inhibitors have a consistent benefit across all stages of dementia; their benefit in mild cognitive impairment and prodromal AD is unproven. Memantine has a smaller benefit on cognition overall which is limited to the moderate to severe stages, and the combination of a cholinesterase inhibitor and memantine may have additional efficacy. Evidence for the efficacy of vitamin E supplementation and medical foods is weak but might be considered in the context of cost, availability, and safety in individual patients. Apparently promising disease-modifying interventions, mostly addressing the amyloid cascade hypothesis of AD, have recently failed to demonstrate efficacy so novel approaches must be considered.

Association of Antidementia Drugs and Mortality in Community-Dwelling Frail Older Patients With Dementia: The Role of Mortality Risk Assessment

OBJECTIVE

To evaluate whether treatment with antidementia drugs is associated with reduced mortality in older patients with different mortality risk at baseline.

DESIGN

Retrospective.

SETTING

Community-dwelling.

PARTICIPANTS

A total of 6818 older people who underwent a Standardized Multidimensional Assessment Schedule for Adults and Aged Persons (SVaMA) evaluation to determine accessibility to homecare services or nursing home admission from 2005 to 2013 in the Padova Health District, Italy were included.

MEASUREMENTS

Mortality risk at baseline was calculated by the Multidimensional Prognostic Index (MPI), based on information collected with the SVaMA. Participants were categorized to have mild (MPI-SVaMA-1), moderate (MPI-SVaMA-2), and high (MPI-SVaMA-3) mortality risk. Propensity score-adjusted hazard ratios (HR) of 2-year mortality were calculated according to antidementia drug treatment.

RESULTS

Patients treated with antidementia drugs had a significant lower risk of death than untreated patients (HR 0.82; 95% confidence interval [CI] 0.73-0.92 and 0.56; 95% CI 0.49-0.65 for patients treated less than 2 years and more than 2 years treatment, respectively). After dividing patients according to their MPI-SVaMA grade, antidementia treatment was significantly associated with reduced mortality in the MPI-SVaMA-1 mild (HR 0.71; 95% CI 0.54-0.92) and MPI-SVaMA-2 moderate risk (HR 0.61; 95% CI 0.40-0.91, matched sample), but not in the MPI-SVaMA-3 high risk of death.

CONCLUSIONS

This large community-dwelling patient study suggests that antidementia drugs might contribute to increased survival in older adults with dementia with lower mortality risk.

Activation of Two Different Drugs Used in Alzheimer's Disease Treatment on Human Carbonic Anhydrase Isozymes I and II Activity: an In Vitro Study

OBJECTIVES

Human carbonic anhydrase I and II (hCAI, II) isoenzymes were purified from human erythrocyte. Kinetic interactions between the enzymes and memantine and donepezil, two different drugs used in Alzheimer's disease (AD) treatment, were investigated.

MATERIALS AND METHODS

The purification procedure was composed of preparation of homogenate (or hemolysate) and affinity chromatography on Sepharose 4B-L-tyrosine-sulfanilamide.

RESULTS

Both drug exhibited in vitro activator effects on hCAI and II enzymes activity. Strong activations were found for these compounds: The CA values of memantine and donepezil against hCAI were 0.013 µM and 1.8 µM, respectively. The KA values of memantine and donepezil against hCAII were 0.045 µM and 3.7 µM, respectively.

CONCLUSION

Since the levels of CA isoenzymes are low in patients with AD or in the older population, increasing activities of these isoenzymes are important for these patients. The effect of these drugs used in AD treatment was thought to be caused by positive changes in the levels of carbonic anhydrase isoenzymes.

Acetylcholinesterase inhibitors for treating dementia symptoms - a safety evaluation

INTRODUCTION

The prevalence of Alzheimer's disease (AD) continues to rise, while treatment options for cognitive impairment are limited. Acetylcholinesterase inhibitors (AChEIs) aim to provide symptomatic benefit for cognitive decline, however these drugs are not without adverse events (AEs). The safety profile of each drug must be taken carefully into consideration before being prescribed, as new dosages and formulations have recently been approved. Areas covered: Donepezil, galantamine and rivastigmine are the three AChEIs approved for the treatment of varying stages of AD. Numerous clinical trials and post-marketing studies have evaluated the safety of these medications. This article will review the safety, efficacy and tolerability of these drugs in treating AD. Topics including pharmacovigilance databases, concomitant drug interactions, prescribing cascades, and treatment discontinuation are also covered. Expert opinion: AChEI use in those with mild, moderate or severe AD provide modest improvements in cognition, function and behavior. The pharmacological treatment of AD using AChEIs is associated with generally mild AEs. Differences in drug formulations should be taken into account when determining the most appropriate route of administration for each individual. Furthermore, discontinuation of AChEIs must be carefully monitored as it may be associated with worsening cognitive impairment.

Pharmacotherapeutic strategies in the treatment of severe Alzheimer's disease

INTRODUCTION

Alzheimer's disease (AD) is a slowly progressive neurodegenerative disease. Patients with severe AD often require assistance with daily functioning and have a substantially higher probability of admission to nursing homes compared to the general population.

AREAS COVERED

Medications approved by the US Food and Drug Administration for the treatment of severe AD include the cholinesterase inhibitors (ChEIs), donepezil (10 and 23 mg/day) and rivastigmine (transdermal patch, 13.3 mg/24 hours), and the N-methyl-D-aspartate receptor antagonist memantine (immediate- and extended-release formulations). This article will review the efficacy, safety, and tolerability data of these agents in the treatment of severe AD. Issues related to combination therapy, neuropsychiatric symptoms, and treatment discontinuation are also discussed.

EXPERT OPINION

AD therapeutics provide benefits on measures of cognition, functioning, behavior, and global status even in the severe stages of AD. Combination therapy with memantine and ChEIs may provide additive benefits compared with ChEI monotherapy. Decisions regarding discontinuation of these medications should be made on a case-by-case basis, with some evidence suggesting that discontinuation may worsen cognition and functional impairment. It is recommended that patients entering the terminal stages of AD discontinue all medications not necessary for comfort.

Role of Donepezil in the Management of Neuropsychiatric Symptoms in Alzheimer's Disease and Dementia with Lewy Bodies

Alzheimer's disease (AD) is a progressive condition that affects cognition, function, and behavior. Approximately 60-90% of patients with AD develop neuropsychiatric symptoms (NPS) such as hallucinations, delusions, agitation/aggression, dysphoria/depression, anxiety, irritability, disinhibition, euphoria, apathy, aberrant motor behavior, sleep disturbances, appetite and eating changes, or altered sexual behavior. These noncognitive behavior changes are thought to result from anatomical and biochemical changes within the brain, and have been linked, in part, to cholinergic deficiency. Cholinesterase inhibitors may reduce the emergence of NPS and have a role in their treatment. These agents may delay initiation of, or reduce the need for, other drugs such as antipsychotics. This article summarizes the effects of donepezil, a cholinesterase inhibitor, on the NPS of dementia with emphasis on AD and dementia with Lewy bodies.

Alzheimer's disease and language impairments: social intervention and medical treatment

Communication is very important for people to be successfully integrated into social environment and make and maintain relationship. Particularly, language difficulties lead to social exclusion of the people affected with Alzheimer's disease (AD) and contribute to a significant decrease in the quality of their life and also have a big impact on their family members who in most cases become their caregivers who need to communicate with their loved ones in order to meet their needs. Therefore, the goal of this study is to describe language impairments in the individual phases of AD and discuss their improvement with respect to AD on the basis of literature review. The authors of this article use traditional research methods in order to achieve the goal set mentioned earlier. First, a method of literature review of available sources describing language impairments in the individual phases of AD is exploited. Second, to show how informal caregivers and relevant drugs can successfully intervene in the improvement of these language impairments, a method of comparison of different research studies exploring such social intervention and medical treatment is used.

Donepezil across the spectrum of Alzheimer's disease: dose optimization and clinical relevance

Alzheimer's disease (AD) is an irreversible and progressive neurodegenerative disorder. AD is the most common cause of dementia worldwide, and its incidence is increasing in line with population aging. The primary feature of AD is progressive cognitive decline, and severe AD is characterized by reduced communication skills and mobility. However, successful treatment can substantially improve quality of life. Donepezil is an acetylcholinesterase inhibitor approved for use across the full spectrum of mild, moderate, and severe AD. Donepezil has been available at doses of 5 or 10 mg once daily for more than a decade and, more recently, a single high once-daily sustained-release 23-mg dose has been approved for treatment of patients with moderate to severe AD. The rationale for the higher dose formulation was the expected increase in acetylcholinesterase inhibition given the dose-response relationship of donepezil, with the benefits of the higher dose being most apparent in patients with more advanced AD. Donepezil 5 and 10 mg/day have been well studied in mild-to-moderate AD, and a clinical trial has confirmed the benefits of donepezil 23 mg/day in patients with moderate to severe AD, particularly for language and visuospatial ability. This review presents an overview of the evidence for donepezil across the spectrum of AD, with a focus on dose optimization for disease progression.

Language impairment in Alzheimer's disease and benefits of acetylcholinesterase inhibitors

Alzheimer’s disease is characterized by progressively worsening deficits in several cognitive domains, including language. Language impairment in Alzheimer’s disease primarily occurs because of decline in semantic and pragmatic levels of language processing. Given the centrality of language to cognitive function, a number of language-specific scales have been developed to assess language deficits throughout progression of the disease and to evaluate the effects of pharmacotherapy on language function. Trials of acetylcholinesterase inhibitors, used for the treatment of clinical symptoms of Alzheimer’s disease, have generally focused on overall cognitive effects. However, in the current report, we review data indicating specific beneficial effects of acetylcholinesterase inhibitors on language abilities in patients with Alzheimer’s disease, with a particular focus on outcomes among patients in the moderate and severe disease stages, during which communication is at risk and preservation is particularly important.

Pharmacological recommendations for the symptomatic treatment of dementia: the Canadian Consensus Conference on the Diagnosis and Treatment of Dementia 2012

BACKGROUND

While there have been no new medications approved for the treatment of Alzheimer's disease (AD) or other dementias in Canada since 2004, the Canadian Consensus Conference on the Diagnosis and Treatment of Dementia (CCCDTD) reviewed and updated the clinical practice guidelines on the pharmacological management of dementia that were published previously.

METHODS

This review focused on the literature for the pharmacological treatment of dementia based on studies published since the third CCCDTD in 2006. A literature search of English-language medical databases was preformed for studies pertaining to the pharmacological treatment of AD and other dementias that examined the management of cognitive and functional impairment, as well as neuropsychiatric symptoms. All previous recommendations were reviewed, and only those that required updating based on new published studies were revised. Several new recommendations were also added. Recommendations were rated for quality of evidence and were approved by consensus.

RESULTS

There were 15 revised or new recommendations approved by consensus. The revised recommendations included acknowledging that cholinesterase inhibitors (ChEIs) possess a class effect and any of the agents can be used for AD across the spectrum of severity and with co-existing cerebrovascular disease. There was insufficient evidence to recommend for or against the use of ChEIs in combination with memantine for the primary indication of treating neuropsychiatric symptoms, or for the treatment of vascular dementia. Recommendations for the discontinuation of cognitive enhancers were revised and clarified, as well as the risks associated with discontinuing these drugs. ChEIs were recommended as a treatment option for dementia with Parkinson's disease. Risks associated with use of antipsychotics for neuropsychiatric symptoms were strengthened, and guidelines regarding the use of antidepressants for affective disturbances in dementia were weakened, and are now considered an option but not a firm recommendation. Valproate was recommended not to be used, and there was insufficient evidence to recommend for or against the use of selective serotonin reuptake inhibitors or trazodone for the treatment of agitation and aggression.

CONCLUSION

In spite of the lack of new therapeutic agents for the treatment of dementia, recent studies have helped to clarify and strengthen recommendations to optimize the pharmacological management of these illnesses.

Evaluating the cognitive effects of donepezil 23 mg/d in moderate and severe Alzheimer's disease: analysis of effects of baseline features on treatment response

Background

Treatment of Alzheimer’s disease with acetylcholinesterase inhibitors can result in symptomatic benefits, but patients often show variable responses. The objective of this post hoc analysis was to investigate relationships between easily identifiable baseline characteristics/demographics and cognitive response in patients treated with either donepezil 23 mg/d or 10 mg/d and to identify factors potentially influencing response.

Methods

A post hoc analysis was conducted using data from a large, 24-week, randomized, double-blind, international study enrolling patients with moderate to severe Alzheimer’s disease (baseline Mini-Mental State Examination [MMSE], 0-20) (NCT 00478205). Cognitive changes in subgroups of patients based on selected baseline and demographic characteristics were compared using the least squares mean changes in Severe Impairment Battery scores at Week 24. Univariate and multivariate analyses were also performed.

Results

Donepezil 23 mg/d provided statistically significant incremental cognitive benefits over donepezil 10 mg/d irrespective of baseline functional severity, measured by scores on the Alzheimer’s Disease Cooperative Study-Activities of Daily Living-severe version (P < 0.05). When patients were categorized by baseline cognitive severity (MMSE score), significant benefits of donepezil 23 mg/d over 10 mg/d were seen in both subgroups when based on MMSE scores of 0-9 versus 10-20 (P < 0.02 and P < 0.01, respectively), and in the more severe subgroup when based on MMSE scores of 0-16 versus 17-20 (P < 0.0001 and P > 0.05). Statistically significant incremental cognitive benefits of donepezil 23 mg/d over 10 mg/d were also observed regardless of age, gender, weight, or prestudy donepezil 10 mg/d treatment duration (P < 0.05). In the multivariate analysis, the only significant interaction was between treatment and baseline MMSE score.

Conclusions

The cognitive benefits of donepezil 23 mg/d over 10 mg/d were achieved regardless of the patient’s age, gender, weight, duration of prior donepezil 10 mg/d, and functional severity. The influence of baseline cognitive severity on response seemed to be dependent on the level of impairment, with cognitive benefits of donepezil 23 mg/d over 10 mg/d most apparent in those patients at a more advanced stage of disease. These data may be useful in helping practicing physicians make informed decisions for their patients with advanced Alzheimer’s disease.

Effects of donepezil 23 mg on Severe Impairment Battery domains in patients with moderate to severe Alzheimer's disease: evaluating the impact of baseline severity

INTRODUCTION

The US Food and Drug Administration approved a 23 mg daily dose of donepezil for treatment of moderate to severe Alzheimer's disease (AD) based on outcomes from a large trial comparing the 23 mg/day dose with the standard 10 mg/day dose. Results from this study indicated that after 24 weeks, donepezil 23 mg/day provided significant cognitive benefits over donepezil 10 mg/day, measured using the Severe Impairment Battery (SIB). In the analyses reported herein, we further characterize the range of cognitive domains impacted by treatment with donepezil 23 mg/day.

METHODS

A post hoc analysis was conducted using data from a 24-week, randomized, double-blind trial comparing donepezil 23 mg/day versus 10 mg/day in 1,467 patients with moderate to severe AD (baseline Mini-Mental State Examination (MMSE) score 0 to 20). Changes from baseline to week 24 in the nine SIB domain scores were analyzed in the intent-to-treat (ITT) population (baseline MMSE 0 to 20), in patients with more severe baseline AD (MMSE 0 to 16), and in severity strata based on baseline MMSE scores (0 to 5, 6 to 10, 11 to 15, 16 to 20).

RESULTS

In the ITT population, changes in six of the nine SIB domains favored donepezil 23 mg/day over donepezil 10 mg/day. LS mean treatment differences were significant for the language, visuospatial ability, and construction domains. In the more advanced cohort of patients (MMSE 0 to 16 at baseline), LS mean treatment differences were statistically significant favoring donepezil 23 mg/day in five of the nine domains: language, memory, visuospatial ability, attention, and construction. Descriptive analysis of LS mean changes in SIB domain scores in the four baseline severity strata showed variable patterns of response; overall, cognitive benefits of donepezil 23 mg/day were greatest in patients with MMSE scores of 0 to 15.

CONCLUSIONS

These results suggest that donepezil 23 mg/day provides benefits over 10 mg/day across a range of cognitive domains. The magnitude of benefit and domains impacted varied depending on the stage of AD; significant benefits with higher dose donepezil were most apparent at more advanced stages of AD and were most prominent in the language domain.

Somatic comorbidities and Alzheimer's disease treatment

Therapeutic strategies in Alzheimer’s disease (AD) must take into account the characteristics of elderly people, who often have somatic comorbidities. Moreover, demented patients are more frequently frailer than older people. They have a higher number of admissions to hospital, a greater prevalence of complications and an increased risk of death. Therapeutic decisions for these patients have to be approached cautiously: aging, a more elevated comorbidity/polytherapy index and frailty contribute to enhance the risk of pharmacological adverse events and drug interactions. The aim of the present study was to focus on risk–benefit profile of pharmacological therapy for AD in relation to somatic comorbidities that often affect these patients. A Medline search (from 2001 to 2012) was performed using as key words dementia, Alzheimer’s disease, drug treatment, somatic comorbidities, side effects/adverse events and elderly. Cholinesterase inhibitors (ChEIs) and memantine represent the main pharmacological strategies effective in reducing the progression of cognitive decline and functional loss in AD. Many conditions very common in the elderly may restrict the use of ChEIs and/or treatment efficacy in AD patients. Memantine has a good efficacy and tolerability profile with better safety in pulmonary, cardiovascular and central nervous system comorbidities compared to ChEIs. Drug interactions with memantine are also more favorable since they concern mostly drugs not commonly used in the elderly. Only a careful evaluation of the associated somatic diseases, taking into account different drugs safety indexes and tolerability, can lead to personalized treatment management, in order to maximize drug efficacy and optimize quality of life.

Memantine in patients with Alzheimer's disease receiving donepezil: new analyses of efficacy and safety for combination therapy

Introduction

Memantine and cholinesterase inhibitors potentially offer additional benefits in Alzheimer's disease (AD) when used together. This study assessed the efficacy and safety of combination treatment with memantine added to stable donepezil in patients with moderate to severe AD, and in a subset with moderate AD.

Methods

Post hoc meta-analyses of data combined from two 24-week, randomised, double-blind, placebo-controlled trials of memantine 20 mg/day versus placebo, added to a stable cholinesterase inhibitor, were conducted. Data were included for all patients receiving donepezil 10 mg/day with Mini-Mental State Examination (MMSE) scores < 20 (n = 510). Efficacy was assessed using measures of cognition, function, and global status. Furthermore, marked clinical worsening, defined as concurrent deterioration from baseline in the three main efficacy domains, and safety, measured by treatment-emergent adverse events, were assessed. Analyses were performed for patients with moderate to severe AD (MMSE 5-19; MOD-SEV subgroup), and also for patients with moderate AD (MMSE 10-19; MOD subgroup; n = 367).

Results

At week 24, in the MOD-SEV subgroup, patients receiving memantine added to donepezil significantly outperformed those receiving placebo added to donepezil in measures of cognition (P < 0.0001), function (P = 0.02), and global status (P = 0.010), with standardised mean differences (SMDs) of 0.36, 0.21, and 0.23, respectively (all last observation carried forward). Similarly, in the MOD subgroup, significant benefits were observed for cognition (P = 0.008), function (P = 0.04) and global status (P = 0.008), with SMDs of 0.28, 0.21, and 0.28, respectively. Significantly fewer patients receiving memantine added to donepezil showed marked clinical worsening than those receiving placebo added to donepezil, in both subgroups (MOD-SEV: 8.7% versus 20.4%, P = 0.0002; MOD: 5.9% versus 15.0%, P = 0.006). The incidence of adverse events was similar between treatment groups.

Conclusions

These results support and extend previous evidence that combination treatment with memantine added to stable donepezil in patients with moderate AD, and in those with moderate to severe AD, is associated with significant benefits in reducing 24-week decline in cognition, function and global status. Combination treatment produces substantially reduced rates of marked clinical worsening, has good safety and tolerability, and generates effect sizes that are both statistically significant and clinically meaningful.

Drug therapy optimization at the end of life

Older people reaching end-of-life status are particularly at risk of adverse effects of drug therapy. Polypharmacy, declining organ function, co-morbidity, malnutrition, cachexia and changes in body composition all sum up to increase the risk of many drug-related problems in individuals who receive end-of-life care. End of life is defined by a limited lifespan or advanced disability. Optimal prescribing for end-of-life patients with multimorbidity, especially in those dying from non-cancer conditions, remains mostly unexplored, despite the increasing recognition that the management goals for patients with chronic diseases should be redefined in the setting of reduced life expectancy. Most drugs used for symptom palliation in end-of-life care of older patients are used without solid evidence of their benefits and risks in this particularly frail population. Appropriate dosing or optimal administration routes are in most cases unknown. Avoiding or discontinuing drugs that aim to prolong life or prevent disability is usually common sense in end-of-life care, particularly when the time needed to obtain the expected benefits from the drug is longer than the life expectancy of a particular individual. However, discontinuation of drugs is not standard practice, and prescriptions are usually not adapted to changes in the course of advanced diseases. Careful consideration of remaining life expectancy, time until benefit, goals of care and treatment targets for each drug seems to be a sensible framework for decision making. In this article, some key issues on drug therapy at the end of life are discussed, including principles of decision making about drug treatments, specific aspects of drug therapy in some common geriatric conditions (heart failure and dementia), treatment of acute concurrent problems such as infections, evidence to guide the choice and use of drugs to treat symptoms in palliative care, and avoidance of some long-term therapies in end-of-life care. Solid evidence is lacking to guide optimal pharmacotherapy in most end-of-life settings, especially in non-cancer diseases and very old patients. Some open questions for research are suggested.

[Pharmacological treatment of dementia: when, how and for how long. Recommendations of the Working Group on Dementia of the Catalan Society of Geriatrics and Gerontology]

Dementia in general--and Alzheimer's disease (AD) in particular--are bound to loom large among the most acute healthcare, social, and public health problems of the 21st century. AD shows a degenerative progression that can be slowed down--yet not halted--by today's most widely accepted specific treatments (those based on cholinesterase inhibitors as well as those using memantine). There is enough evidence to consider these treatments advisable for the mild, moderate and severe phases of the illness. However, in the final stage of the disease, a decision has to be made on whether to withdraw such treatment or not. In this paper, the Working Group on Dementia for the Catalan Society of Geriatrics and Gerontology reviews the use of these specific pharmacological treatments for AD, and, drawing on the scientific evidence thus gathered, makes a series of recommendations on when, how, and for how long, the currently existing specific pharmacological treatments should be used.

A review of the effects of memantine on clinical progression in Alzheimer's disease

BACKGROUND

As Alzheimer's disease (AD) progresses, patients become increasingly dependent on others, placing a substantial impact on the daily lives of patients and caregivers. A treatment that slows clinical progression is a realistic and meaningful therapeutic goal for patients and caregivers. If given early, such a treatment would be expected to maximise any potential benefit. Memantine has shown clinical benefits in the key domains of AD, both as monotherapy and in combination with a cholinesterase inhibitor (ChEI).

METHODS

Memantine now has a considerable database of published studies and is associated with benefits in aspects of behaviour, cognition and communication, and on clinical progression. The results of these clinical studies are reviewed.

RESULTS

Short-term clinical studies (≤28 weeks) have shown that memantine reduces clinical worsening and has also demonstrated positive effects in aspects of cognition--language, memory, praxis, functional communication--and in activities of daily living. Furthermore, memantine has been shown to reduce the rate of emergence of troublesome behaviour in patients with AD who were asymptomatic at baseline. Long-term follow-up studies (>1 year) have shown that the benefits of memantine are sustained and increase over time, and that memantine can delay nursing home placement in patients with AD.

CONCLUSIONS

These findings provide evidence for the benefits of memantine, either alone or in combination with a ChEI, in slowing clinical progression in AD, and indicate that early treatment initiation may maximise clinical success. The benefits of memantine increase over time, allowing patients to remain independent for longer, alleviating caregiver burden and delaying institutionalisation.

Underrecognition and undertreatment of dementia in Italian nursing homes

OBJECTIVE

To determine the prevalence of dementia diagnoses and the use of antidementia drugs in a cohort of Italian older nursing home (NH) residents.

DESIGN

Cross-sectional study.

SETTING

The NH residents participating in 2 studies: the U.L.I.S.S.E. study and the Umbria Region survey.

PARTICIPANTS

A total of 2215 nursing home residents.

MEASUREMENT

Each resident underwent a comprehensive geriatric assessment at baseline by means of the RAI MDS 2.0. Dementia diagnosis was based on ICD-9 codes.

RESULTS

The prevalence of dementia diagnosis according to ICD-9 codes was 50.7% (n = 1123), whereas 312 subjects had cognitive impairment with a cognitive performance scale score ≥3 without a diagnosis of dementia. Only 56 NH residents were treated (5% of the sample) and the main drugs used were cholinesterase inhibitor, whereas only 1 subject was treated with memantine. Limiting our analysis to patients with mild to moderate Alzheimer's disease, who are those reimbursed by the public health care system for receiving antidementia drugs, the percentage rose to 11.3%.

CONCLUSION

These findings demonstrate a high rate of underdiagnosis and undertreatment of dementia in Italian NH residents. Potential explanations include the lack of systematic assessment of cognitive functions, the limitations to antidementia drug reimbursement, the complexity of the reimbursement procedure itself, and the high prevalence of patients with severe dementia. Older NH residents still lack proper access to state-of-the-art diagnosis and treatment for a devastating condition such as dementia.

Treatment of Alzheimer's disease in Brazil: I. Cognitive disorders

This article reports the recommendations of the Scientific Department of Cognitive Neurology and Aging of the Brazilian Academy of Neurology for the treatment of Alzheimer’s disease (AD) in Brazil, with special focus on cognitive disorders. It constitutes a revision and broadening of the 2005 guidelines based on a consensus involving researchers (physicians and non-physicians) in the field. The authors carried out a search of articles published since 2005 on the MEDLINE, LILACS and Cochrane Library databases. The search criteria were pharmacological and non-pharmacological treatment of cognitive disorders in AD. Studies retrieved were categorized into four classes, and evidence into four levels, based on the 2008 recommendations of the American Academy of Neurology. The recommendations on therapy are pertinent to the dementia phase of AD. Recommendations are proposed for the treatment of cognitive disorders encompassing both pharmacological (including acetyl-cholinesterase inhibitors, memantine and other drugs and substances) and non-pharmacological (including cognitive rehabilitation, physical activity, occupational therapy, and music therapy) approaches. Recommendations for the treatment of behavioral and psychological symptoms of dementia due to Alzheimer’s disease are included in a separate article of this edition.

Analyzing the impact of 23 mg/day donepezil on language dysfunction in moderate to severe Alzheimer's disease

Introduction

Progressive language impairment is among the primary components of cognitive decline in Alzheimer's disease (AD). Because expressive and receptive language help to maintain emotional connections to caregivers and support the management of AD patients' functional needs, language plays a critical role in patients' emotional and physical health. Using data from a large prospective clinical trial comparing two doses of donepezil in patients with moderate to severe AD, we performed a post hoc analysis to determine whether a higher dose of donepezil was associated with greater benefits in language function.

Methods

In the original randomized, double-blind clinical trial, 1,467 patients with moderate to severe AD (baseline Mini-Mental State Examination (MMSE) score 0 to 20) were randomized 2:1 to receive donepezil 23 mg/day or to continue on donepezil 10 mg/day for 24 weeks. In this post hoc analysis, the Severe Impairment Battery-Language scale (SIB-L) and a new 21-item SIB-derived language scale (SIB[lang]) were used to explore differences in language function between the treatment groups. Correlations between SIB-L and SIB[lang] scores and scores on the severe version of the Alzheimer's Disease Cooperative Study-Activities of Daily Living inventory (ADCS-ADL-sev), the Clinician's Interview-Based Impression of Severity-plus caregiver input/Clinician's Interview-Based Impression of Change-plus caregiver input (CIBIS-plus/CIBIC-plus) and the MMSE were also investigated.

Results

At week 24, treatment with donepezil 23 mg/day was associated with an improvement in language in the full intention-to-treat population, whereas language function declined in the group treated with donepezil 10 mg/day (SIB-L treatment difference 0.8, P = 0.0013; SIB[lang] treatment difference 0.8, P = 0.0009). Similar results were observed in a cohort of patients with more severe baseline disease (MMSE score 0 to 16). At baseline and week 24, correlations between the SIB-derived language scales and the ADCS-ADL-sev and CIBIC-plus were moderate, but the correlations were stronger between the language scales and the MMSE scores.

Conclusions

Patients with moderate to severe AD receiving donepezil 23 mg/day showed greater language benefits than those receiving donepezil 10 mg/day as measured by SIB-derived language assessments. Increasing the dose of donepezil to 23 mg/day may provide language benefits in patients with moderate to severe AD, for whom preservation of language abilities is especially critical.

ClinicalTrials.gov identifier: NCT00478205

Recommended measures for the assessment of behavioral disturbances associated with dementia

OBJECTIVE

The study reviewed all the published instruments used for the assessment, diagnosis, screening, and outcomes monitoring/evaluation of behavioral disturbances associated with dementia (BDAD) to recommend a set of psychometrically valid measures for clinicians and researchers to use, across a range of different practice settings.

METHODS

The study involved a broad scoping search, followed by a series of in-depth literature reviews on 29 instruments using scientific literature databases (MEDLINE, PsycINFO, CINAHL, and the Cochrane Library) and various national, international government, and government agency websites and professional organization websites. External consultations from measurement, clinical and research experts in dementia care, consumer representatives, and policy/decision makers, were sought in selecting the best instruments and in making the final recommendations.

FINDINGS

Key attributes and psychometric properties of a short list of five instruments were measured against prespecified criteria. The Neuropsychiatry Inventory (NPI) and the Behavioral Pathology in Alzheimer's Disease Rating Scale (BEHAVE-AD) were rated as the best measures for assessment of behavioral disturbances, followed by the Consortium to Establish a Registry for Alzheimer's Disease-Behavior Rating Scale for Dementia (CERAD-BRSD), the Dementia Behavior Disturbance Scale, and the Neurobehavioral Rating Scale.

CONCLUSION

The use of valid and standardized outcome measures for the assessment of BDAD is critical for epidemiological studies, prevention, early intervention and treatment of dementia conditions, and funding for relevant healthcare services. The review recommends the NPI and BEHAVE-AD as the most appropriate measures for both clinical and research, whereas the CERAD-BRSD is suited better for research. The review was designed for the Australian context; however, the findings are applicable in other developed countries.

Either called "chemobrain" or "chemofog," the long-term chemotherapy-induced cognitive decline in cancer survivors is real

CONTEXT

In recent years, there is growing evidence in the medical literature to support an association between administration of commonly used chemotherapeutic agents and an increased risk for cognitive impairment.

OBJECTIVES

We herein critically summarize data relating to the pathophysiological mechanisms by which chemotherapy may induce cognitive impairment in patients surviving from solid tumors. The clinical and epidemiological characteristics and the proposed management strategies to counter chemotherapy-induced cognitive impairment (CICI) also are presented.

METHODS

References for this review were identified by searches of PubMed from 1995 until December 2009 with related terms.

RESULTS

Both the pathogenetic mechanisms and the overall clinical nature of CICI remain vaguely defined. Findings indicate that CICI is a relatively common event that, in most of the cases, remains underdiagnosed, thereby adversely affecting the quality of life of patients with cancer. Effective pharmacological interventions toward the symptomatic or prophylactic management of CICI also are lacking.

CONCLUSION

Either called "chemobrain" or "chemofog," the long-term CICI in cancer survivors is real. The need for multidisciplinary care interventions toward a timely diagnosis and management of CICI is clearly warranted.

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

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

Donepezil: A Review of Pharmacological Characteristics and Role in the Management of Alzheimer Disease

Donepezil is a potent, selective, noncompetitive, and rapidly reversible inhibitor of acetylcholinesterase (AChEI) licensed for the treatment of Alzheimer disease (AD); and is the first and only AChEI licensed for the treatment of severe AD. Its efficacy as monotherapy, or in combination with the NMDA-agonist, memantine, has been documented in several randomised double-blind, placebo-controlled, short-term clinical trials, as well as long-term extension trials and observational studies. Donepezil is a well tolerated drug that is generally safe as demonstrated even in patients with multiple co-morbidities receiving polypharmacy. It has been shown that donepezil improves cognition and global function in patients with mild-to-moderate AD; and long-term efficacy is maintained for up to 50 weeks. There is a dose-response relationship, with higher doses more likely to produce symptomatic benefit. Furthermore, donepezil-treated patients may improve cognitively and show global clinical improvement in all disease stages, including severe AD. Less consistent results in all disease stages were obtained on measures of function and behavior, and observations of mood. No effect on transition to AD has been found in long-term, randomized clinical trials in mild cognitive impairment (MCI). Cost-effectiveness of the treatment has been questioned by one long-term open-label societal study of 2-years duration. This study reported modest improvement of cognition but no statistically significant benefits during donepezil treatment as compared to placebo, in terms of rates of institutionalization and progression toward greater disability. However, there is a need for further research on clinically meaningful outcomes and treatment benefits favored by patients and caregivers, which are traditionally not defined as outcomes in clinical trials. Likewise, we need to know how to select responders, what is an optimal AChE inhibition particularly during the long-term treatment, in which patients the dosage should be increased for a sustained benefit, what is the optimal duration of treatment and when is meaningful to stop the treatment. After almost two decades of donepezil use in everyday clinical practice these issues are still unresolved.

Efficacy and safety of donepezil in patients with Alzheimer's disease in assisted living facilities

The aim of this 12-week, open-label study was to determine the safety and efficacy of donepezil in participants with Alzheimer's disease (AD) residing in assisted living facilities (ALFs). Participants received 5 mg donepezil daily for 6 weeks followed by 10 mg daily for 6 weeks. Primary and secondary outcomes were change from baseline in Mini-Mental State Examination (MMSE) and Neuropsychiatric Inventory 8 (NPI-8) scores, respectively. Safety was assessed by adverse events (AEs) and laboratory tests. Of the 97 participants, 76 completed the study. Mean MMSE score (18.7 at baseline) improved 1.8 points (P < .0001) at study end. Total NPI-8 score improved 1.8 points (P = .043). The most frequent AEs were nausea and diarrhea. Donepezil improved cognition and behavior and was safe and well tolerated. The results suggest a need for proactive screening and diagnosis of AD and support the value of treatment and use of donepezil in participants residing in ALFs.

Evolving attitudes to Alzheimer's disease among the general public and caregivers in Europe: findings from the IMPACT survey

Understanding and appreciating the awareness of, and attitudes towards, Alzheimer's disease (AD) in the general public is of paramount importance to those charged with the development of health care policy. Furthermore, it is essential that this policy be formulated with consideration given to both the attitudes of the general population and to those within society more directly affected by AD; namely, the caregivers of patients with the disease. In the IMPACT survey, approximately 1000 members of the general public and 250 caregivers in 5 European countries (France, Germany, Italy, Spain, and the United Kingdom) completed a 30-minute, Web-based questionnaire. In this article, we compare and contrast the attitudes and opinions of these populations in an attempt to define specific themes. Indeed, caregivers were more concerned about consequences of growing old and were more fearful of AD than general public respondents, although a high proportion in both groups acknowledged the significant impact of the disease. Similarly, although most respondents in the 2 groups recognised that early signs and symptoms of AD are difficult to detect, caregivers were more skeptical of the abilities of both primary physicians and specialists to detect these early signs and symptoms. In terms of treatment, caregivers were less convinced of the effectiveness of treatment beyond the early stages of AD and more likely to agree that current treatments are associated with side effects. Respondents in both groups had a negative view of their government's investment in AD, but caregivers, particularly those in France, Spain and the United Kingdom, were more likely to feel that their government acts as a barrier to treatment. Some survey respondents from the 2 groups also had a negative view of their governments' attempts to raise awareness of AD and make its treatment a high priority. Overall, comparison of responses from these 2 groups suggests that caregivers' personal experiences of AD profoundly affect their attitudes and perceptions surrounding the disease.

Implications of the Impact Survey for payors across Europe

People involved with development of health care policy must be appreciative of the social and economic challenges that will likely develop as a result of the rise in Alzheimer's disease (AD) as the 21st century progresses. Their attitudes, perceptions and understanding regarding AD were captured in the IMPACT survey, a 30-minute Web-based questionnaire. Fifty health policy managers and decision-makers (payors) were recruited, 10 each from 5 European countries--France, Germany, Italy, Spain and the United Kingdom. Most payors felt that AD was underdiagnosed and undertreated in their country (80% and 68%, respectively). Half of all payors felt that their government did not invest enough in treating AD, and 30% felt their government hindered access to drug therapy. Payors believed that treatment should be initiated as early as possible after a diagnosis of AD (82%), and that early treatment can delay progression of the disease (82%). Even more than caregivers, payors agreed that AD can have devastating effects on the family of the sufferer (90% vs 75%; P<0.05). Payors more often cited cancer, stroke and heart disease than AD as affecting their budgets, but cited AD more often than depression, diabetes, HIV/AIDs and arthritis. Cost savings were seen as the most important factor regarding policy decisions. These attitudes of the surveyed payors towards AD and the patients and caregivers affected by it suggest that they may advocate for national and international policies that will facilitate earlier diagnosis and improved access to treatment.