Memantine treatment in patients with moderate to severe Alzheimer disease already receiving donepezil: a randomized controlled trial

Pharmacological treatment of Alzheimer disease

OBJECTIVE

To review the different pharmacological approaches to the cognitive, functional, and behavioural manifestations of Alzheimer disease (AD).

METHODS

We searched and critically analyzed the most recent relevant literature on pharmacological treatment of AD.

RESULTS

The current pharmacological approach to AD treatment is based on vascular prevention and symptomatic therapy with cholinesterase inhibitors (ChEIs) and memantine, an N-methyl-d-aspartic acid antagonist. Clinical trials of 6- to 12-month duration have shown statistically significant benefits with ChEIs and memantine on cognitive, global, functional, and behavioural outcome measures. In general, these benefits are modest. However, they are dose-dependent and reproducible across studies. Most importantly, these benefits are symptomatic as they do not alter disease course. According to the third Canadian Consensus Conference on the Diagnosis and Treatment of Dementia, these agents are considered standard treatment options in AD. We will discuss practical issues related to current pharmacological management, such as setting realistic expectations, management of side effects, switching ChEIs, and the decision to discontinue treatment. The results of clinical trials studying potentially disease-modifying approaches in AD will also be reviewed. Unfortunately, although there remains much promise and enthusiasm, none of these agents has shown consistent benefits, and none are available for use in clinical practice.

CONCLUSION

Pharmacological options are presently available for the symptomatic treatment of AD. These treatments provide mild but sustained benefits. Before disease-modifying approaches become available, optimizing the use of the available treatment options is crucial.

Glaucoma and Alzheimer’s disease in the elderly

Primary open angle glaucoma and Alzheimer’s disease have long been established as two separate pathological entities, primarily affecting the elderly. The progressive, irreversible course of both diseases has significant implications on an aging population. As the complex pathophysiology of the two diseases has progressively unraveled over the past two decades, common pathophysiological changes have also been elucidated. Some of these mechanisms have established a strong grounding, whilst others remain principally speculative. The mutual neuropathological changes in primary open angle glaucoma and Alzheimer’s disease have facilitated the development of neuroprotective strategies. While most of these strategies are still in the preclinical phase, they have shown great promise in experimental animal studies. Further understanding of the common pathophysiology of primary open angle glaucoma and Alzheimer’s disease and their timeline may have great implications on early diagnosis and effective therapeutic targeting.

Economic evaluation of the impact of memantine on time to nursing home admission in the treatment of Alzheimer disease

OBJECTIVE

An observational study showed that combining memantine with a cholinesterase inhibitor (ChEI) treatment significantly delayed admission to nursing homes in patients with Alzheimer disease (AD). Our study aimed to evaluate the economic impact of the concomitant use of memantine and a ChEI, compared with a ChEI alone, in a Canadian population of patients with AD.

METHOD

A cost-utility analysis using a Markov model during a 7-year time horizon was performed according to a societal and Canadian health care system perspective. The Markov model includes the following states: noninstitutionalized, institutionalized, and deceased. The model includes transition probabilities for institutionalization and death, adjusted with mortality rates specific to AD. Utilities associated with institutionalization and noninstitutionalization were included. For the health care system perspective, costs of medication as well as costs of care provided in the community and in nursing homes were considered. For the societal perspective, costs of direct care and supervision provided by caregivers were added.

RESULTS

From both perspectives, the concomitant use of a ChEI and memantine is a dominant strategy, compared with the use of a ChEI alone. On a per patient basis, there was a gain of 0.26 quality-adjusted life years with the treatment including memantine and cost decreases of Can$21 391 and Can$30 512, respectively, for the societal and health care system perspective.

CONCLUSIONS

This economic evaluation indicates that institutionalization is the largest cost component in AD management and that the use of memantine, combined with a ChEI, to treat AD is a cost-effective alternative, compared with the use of a ChEI alone.

Memantine in systemic lupus erythematosus: a randomized, double-blind placebo-controlled trial

OBJECTIVES

Cognitive impairment affects up to 80% of systemic lupus erythematosus (SLE) patients within 10 years of diagnosis. Memantine, a seronergic receptor and nicotine acetylcholine receptor antagonist, acts on the glutamatergic system through the NMDA receptor and is used to treat dementia. We investigated whether it had benefit for SLE cognitive impairment.

METHODS

A randomized double-blind, placebo-controlled single-center 12-week trial of memantine titrated to 20 mg/d was performed, using a 2:1 randomization ratio, in 51 SLE patients. The primary outcome measures were change in the Automated Neuropsychological Assessment Metrics throughput scores at 12 weeks.

RESULTS

There were no statistically significant differences between treatment groups or change from baseline in any of the Automated Neuropsychological Assessment Metrics throughput scores at 6 or 12 weeks. For the American College of Rheumatology cognitive battery, the only statistically significant findings were for the Controlled Oral Word Association Test-S words at 6 and 12 weeks. At 12 weeks, the memantine group exhibited greater improvement compared with the placebo group (3.6 ± 1.8 vs 0.5 ± 3.8 words, P = 0.03). In a subset analysis limited to patients that scored ≥1 standard deviation below normal controls at baseline, no significant differences between treatment groups were found.

CONCLUSIONS

In this first clinical trial of memantine in SLE, patients treated with memantine did not exhibit significant improvement in cognitive performance compared with the placebo group, regardless of the degree of impairment at baseline, with the exception of controlled oral word association.

Measuring therapeutic efficacy in patients with Alzheimer's disease: role of instruments

BACKGROUND/AIMS

Global cognitive scales and meta-analyses thereof are used to appraise therapeutic efficacy over a broad range of disease severity. Clinically, however, different aspects of cognition change in different stages of disease.

METHODS

Calculation of effect sizes for single cognitive functions on treatment as assessed by the Alzheimer's Disease Assessment Scale (ADAS-cog), the Mini-Mental-Status Examination (MMSE), and the Severe Impairment Battery (SIB). In these scales, subdomains of 'cognition', e.g. memory and language, are represented in different proportions. To exemplify the analysis of 'cognition', we used original data of previously published clinical studies with memantine.

RESULTS

Depending on dementia severity and on the scale used, the effect size for memory varies between -0.44 and +0.34 and for language between -0.40 and +0.26.

CONCLUSION

Beyond interstudy variance, effect sizes for treatment with antidementia drugs are subject to disease stage, instruments used, and interaction thereof. Therefore, clinical interpretation is necessary to appraise therapeutic efficacy in clinical studies and meta-analyses thereof when patients with different severity are included or different instruments are used. Alternatively, severity-adapted endpoints should be used for appraisal and meta-analysis of therapeutic efficacy.

Effect of memantine on resting state default mode network activity in Alzheimer's disease

BACKGROUND

Memantine is an approved symptomatic treatment for moderate to severe Alzheimer's disease that reduces the excitotoxic effects of hyperactive glutamatergic transmission. However, the exact mechanism of the effect of memantine in Alzheimer's disease patients is poorly understood. Importantly, the default mode network (DMN), which plays a key role in attention, is hypoactive in Alzheimer's disease and is under glutamatergic control.

OBJECTIVE

To assess the effect of memantine on the activity of the DMN in moderate to severe Alzheimer's disease.

METHODS

Functional magnetic resonance imaging (MRI) data from 15 patients with moderate to severe Alzheimer's disease, seven treated with memantine (mean ± SD age 77 ± 8 years, mean ± SD Mini-Mental State Examination [MMSE] score 16 ± 5) and eight with placebo (mean ± SD age 76 ± 6 years, mean ± SD MMSE score 13 ± 1), were acquired at baseline (T0) and after 6 months of treatment (T6). Resting state components were extracted after spatial normalization in individual patients with independent component analysis. The consistency of the components was assessed using ICASSO and the DMN was recognized through spatial correlation with a pre-defined template. Voxel-based statistical analyses were performed to study the change in DMN activity from T0 to T6 in the two groups.

RESULTS

At T0, the two groups showed similar DMN activity except in the precuneus and cuneus, where the patients who started treatment with memantine had slightly greater activity (p < 0.05 corrected for familywise error [FWE]). The prospective comparison between T0 and T6 in the treated patients showed increased DMN activation mapping in the precuneus (p < 0.05, FWE corrected), while the prospective comparison in the untreated patients did not show significant changes. The treatment × time interaction term was significant at p < 0.05, FWE corrected.

CONCLUSIONS

The results suggest a positive effect of memantine treatment in patients with moderate to severe Alzheimer's disease, resulting in an increased resting DMN activity in the precuneus region over 6 months. Future studies confirming the present findings are required to further demonstrate the beneficial effects of memantine on the DMN in Alzheimer's disease.

Memantine reduces mania-like symptoms in animal models

Memantine, a selective antagonist of the N-methyl-D-aspartate receptor, is approved for the treatment of moderate to severe Alzheimer's disease. Ion dysregulation is thought to be involved in the pathophysiology of bipolar illness, suggesting that memantine may be effective in treating bipolar manic and/or depressive episodes. We utilized two preclinical models of mania that mimic pathophysiologic changes seen in bipolar illness to examine the potential efficacy of memantine in the treatment of this disorder. Locomotor hyperactivity of male Sprague-Dawley rats in an open field was induced with intracerebroventricular (ICV) administration of 10(-3) M ouabain. Memantine (2.5, 5 or 7.5mg/kg), lithium (6.75 mEq/kg), or vehicle were administered acutely via intraperitoneal injection immediately prior to ouabain, then chronically for 7 days (oral memantine 20, 30, and 40 mg/kg/day in water; lithium 2.4 g/kg food). In a second model of bipolar disorder, cycling between population spikes and epileptiform bursts was investigated in rat hippocampal slices treated with ouabain (3.3 μM) alone or in combination with memantine (0.5, 1.0, and 5.0 μM). Ouabain-induced hyperlocomotion was normalized with acute and chronic lithium and chronic use of memantine. Memantine delayed the onset of ouabain-induced-cycling in hippocampal slices. Memantine may have antimanic properties.

Current and emerging therapies for the management of bipolar disorders

Bipolar disorder is a complex condition to treat because agents that may be effective for a specific phase may not be effective for other phases, or may even worsen the overall course of the illness. Over the last decade there has been an increase in research activity in the treatment of bipolar illness. There are now several agents that are well established for the treatment of acute mania (lithium, divalproex, carbamazepine, nearly all antipsychotics), acute bipolar depression (lamotrigine, quetiapine, olanzapine/fluoxetine combination), and relapse prevention (lithium, lamotrigine, divalproex, most second generation antipsychotics). There are also novel treatments that are being studied for all three phases. These include eslicarbazepine, cariprazine, MEM-1003, memantine, tamoxifen and pentazocine for acute mania; pramipexole, modafinil, armodafinil, divalproex, lurasidone, agomelatine, cariprazine, lisedexamfetamine, riluzole, RG-2417, bifeprunox, ropinirole, GSK1014802, and magnetic stimulation for bipolar depression; and asenapine, lurasidone, and cariprazine for relapse prevention. Additionally, there are accumulating data that antidepressants, particularly serotoninergic ones, are not particularly effective in acute bipolar depression and may worsen the course of the illness.

Clinical practice with anti-dementia drugs: a revised (second) consensus statement from the British Association for Psychopharmacology

The British Association for Psychopharmacology (BAP) coordinated a meeting of experts to review and revise its first (2006) Guidelines for clinical practice with anti-dementia drugs. As before, levels of evidence were rated using accepted standards which were then translated into grades of recommendation A to D, with A having the strongest evidence base (from randomized controlled trials) and D the weakest (case studies or expert opinion). Current clinical diagnostic criteria for dementia have sufficient accuracy to be applied in clinical practice (B) and brain imaging can improve diagnostic accuracy (B). Cholinesterase inhibitors (donepezil, rivastigmine, and galantamine) are effective for mild to moderate Alzheimer's disease (A) and memantine for moderate to severe Alzheimer's disease (A). Until further evidence is available other drugs, including statins, anti-inflammatory drugs, vitamin E and Ginkgo biloba, cannot be recommended either for the treatment or prevention of Alzheimer's disease (A). Neither cholinesterase inhibitors nor memantine are effective in those with mild cognitive impairment (A). Cholinesterase inhibitors are not effective in frontotemporal dementia and may cause agitation (A), though selective serotonin reuptake inhibitors may help behavioural (but not cognitive) features (B). Cholinesterase inhibitors should be used for the treatment of people with Lewy body dementias (Parkinson's disease dementia and dementia with Lewy bodies (DLB)), especially for neuropsychiatric symptoms (A). Cholinesterase inhibitors and memantine can produce cognitive improvements in DLB (A). There is no clear evidence that any intervention can prevent or delay the onset of dementia. Although the consensus statement focuses on medication, psychological interventions can be effective in addition to pharmacotherapy, both for cognitive and non-cognitive symptoms. Many novel pharmacological approaches involving strategies to reduce amyloid and/or tau deposition are in progress. Although results of pivotal studies are awaited, results to date have been equivocal and no disease-modifying agents are either licensed or can be currently recommended for clinical use.

Current therapeutic options for Alzheimer's disease

Alzheimer's disease (AD) is the most common neurodegenerative disease in the developed world. The increasing life expectancy in the last years has led to an increase in the prevalence of this age-related condition and has posed an important medical and social challenge for developed societies. The mainstays of current therapy for AD rely on the cholinergic hypothesis developed more than 20 years ago. These compounds, known as acetylcholinesterase inhibitors (AChEIs), inhibit the cholinesterases and aim at improving the brain synaptic availability of acetylcholine. These drugs have been approved for the treatment of AD based on pivotal clinical trials showing modest symptomatic benefit on cognitive, behavioral, and global measures. Memantine, an NMDA antagonist, has been recently included as a therapeutic option for AD. Memantine can be combined safely with AChEIs for an additional symptomatic benefit. During the last years our understanding of the mechanisms underlying the pathogenesis of AD has markedly expanded. Several putative neuroprotective drugs are thoroughly investigated and many of them have reached the clinical arena. It can be anticipated that some of these drugs will be able to slow/prevent the progression of this condition in the near future.

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.

Tolerability and efficacy of memantine add-on therapy to rivastigmine transdermal patches in mild to moderate Alzheimer's disease: a multicenter, randomized, open-label, parallel-group study

OBJECTIVE

To compare the tolerability and efficacy of combination therapy of memantine plus rivastigmine patch with rivastigmine patch monotherapy in patients with mild to moderate Alzheimer's disease (AD).

RESEARCH DESIGN AND METHODS

In this multicenter, randomized, open-label study, patients entered an 8-week run-in period (a 5 cm 2 rivastigmine patch for 4 weeks, then a 10 cm(2) patch for 4 weeks) followed by 16 weeks of memantine plus rivastigmine patch or rivastigmine patch monotherapy. The primary outcome measure was the retention rate at the end of the trial.

CLINICAL TRIAL REGISTRATION

clinicaltrials.gov. NCT01025466.

RESULTS

Overall, 88 and 84 patients received rivastigmine patch with and without memantine, respectively, and of these, 77 (87.5%) and 70 (83.3%) patients completed the study. The difference in retention rate was not significant (95% confidence interval: -6.3-14.7%). The incidence of adverse events (AEs) (53.4 vs. 50.6%) and discontinuation due to AEs (6.8 vs. 4.8%) were not different between patients with and without memantine. The most frequent AEs were skin irritation in patients with and without memantine (42.0 vs. 34.9%, p = 0.71), but discontinuation due to skin irritation was rare (4.5 vs. 2.4%, p = 0.74). The incidence of gastrointestinal AEs was very low in patients with and without memantine (nausea, 2.3 vs. 1.2%; vomiting, 1.1 vs. 1.2%). The Korean Version of the Cohen Mansfield Agitation Inventory scores favored rivastigmine patch monotherapy at the end of treatment (p = 0.01). Changes in other efficacy measures were similar between the groups.

CONCLUSION

There were no significant differences in tolerability and safety between the treatment groups. The combination therapy of memantine plus rivastigmine patch did not show an advantage over rivastigmine patch monotherapy on efficacy analyses. The sample size for comparing tolerability may have been too small to detect a difference of efficacy between the two groups.

Treatment of Alzheimer's disease in Brazil: II. Behavioral and psychological symptoms of dementia

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 behavioral and psychological symptoms of dementia (BPSD). 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 the behavioral and psychological symptoms of 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 BPSD encompassing both pharmacological (including acetyl-cholinesterase inhibitors, memantine, neuroleptics, anti-depressives, benzodiazepines, anti-convulsants plus other drugs and substances) and non-pharmacological (including education-based interventions, physiotherapy, occupational therapy, music therapy, therapy using light, massage and art therapy) approaches. Recommendations for the treatment of cognitive disorders of AD symptoms are included in a separate article of this edition.

Cholinesterase inhibitor and memantine use in newly admitted nursing home residents with dementia

OBJECTIVES

To quantify the use of cholinesterase inhibitors (ChEIs) and memantine in nursing home (NH) residents with dementia upon NH admission and 3 months later and to examine factors associated with reduction in therapy.

DESIGN

Retrospective cohort study.

SETTING

Nationwide sample of U.S. NHs.

PARTICIPANTS

Three thousand five hundred six NH residents with dementia newly admitted in 2006.

MEASUREMENTS

Data from pharmacy dispensing records were used to determine ChEI and memantine medication use upon NH admission and at 3-month follow-up. The Minimum Data Set was used to determine resident- and facility-level characteristics. Severity of dementia was defined using the Cognitive Performance Scale (CPS).

RESULTS

Overall, 40.1% (n=1,407) of newly admitted NH residents with dementia received ChEIs and memantine on NH admission. Use of ChEIs and memantine on admission was significantly greater in residents with mild to moderately severe dementia (41.2%) than in those with advanced dementia (33.3%, P=.001). After 3 months, ChEI and memantine use decreased by about half in both groups (48.6% with mild to moderately severe dementia vs 57.0% with advanced dementia, P<.05). NH residents with advanced dementia were significantly more likely reduce their use of ChEIs and memantine than those with mild to moderately severe dementia (odds ratio=1.44, 95% confidence interval=1.03-2.01, P=.04).

CONCLUSION

Many NH residents with advanced dementia receive ChEIs and memantine upon NH admission, and approximately half of these decrease their medication use over the ensuing months. Further study is required to optimize use of ChEIs and memantine in NH populations and to determine the effects of withdrawing therapy on resident outcomes.

Dementia medications and risk of falls, syncope, and related adverse events: meta-analysis of randomized controlled trials

OBJECTIVES

To evaluate the effect of cholinesterase inhibitors (ChEIs) and memantine on the risk of falls, syncope, and related events, defined as fracture and accidental injury.

DESIGN

Meta-analysis of randomized controlled trials that were identified from MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (no language restriction, through July 2009), and manual search.

SETTING

Community and nursing homes.

PARTICIPANTS

Participants in fifty-four placebo-controlled randomized trials and extension studies of ChEIs and memantine that reported falls, syncope, and related events in cognitively impaired older adults.

MEASUREMENTS

Falls, syncope, fracture, and accidental injury.

RESULTS

ChEI use was associated with greater risk of syncope (odds ratio (OR)=1.53, 95% confidence interval (CI)=1.02-2.30) than placebo but not with other events (falls: OR=0.88, 95% CI=0.74-1.04; fracture: OR=1.39, 95% CI=0.75-2.56; accidental injury: OR=1.13, 95% CI=0.87-1.45). Memantine use was associated with fewer fractures (OR=0.21, 95% CI=0.05-0.85) but not with other events (falls: OR=0.92, 95% CI=0.72-1.18; syncope: OR=1.04, 95% CI=0.35-3.04; accidental injury: OR=0.80, 95% CI=0.56-1.12). There was no differential effect according to type and severity of cognitive impairment, residential status, or length of follow-up, although because of underreporting and small number of events, a potential benefit or risk cannot be excluded.

CONCLUSION

ChEIs may increase the risk of syncope, with no effects on falls, fracture, or accidental injury in cognitively impaired older adults. Memantine may have a favorable effect on fracture, with no effects on other events. More research is needed to confirm the reduction in fractures observed for memantine.

Memantine: a treatment for Alzheimer’s disease with a new formulation

In nearly 20 years, aside from cholinesterase inhibitors, memantine is the only drug approved for the treatment of Alzheimer’s disease (AD). Memantine is an uncompetitive N-methyl-D-aspartate receptor antagonist that blocks pathological glutamate activity while permitting normal physiological function, thus preventing glutamate-induced excitotoxicity. Three Phase III pivotal trials demonstrated memantine’s efficacy in treating moderate-to-severe AD, which led to its initial approval by the EMA in 2002 and US FDA in 2003. The recommended target dose is 10 mg twice daily. The US FDA recently approved an extended-release (ER) formulation of memantine for once-daily 28-mg dosing. Memantine ER was evaluated in a 24-week placebo-controlled trial of patients with moderate-to-severe AD, which found significant benefits for cognition, global assessment, behavior and caregiver burden, but not function. The most common adverse events were headache, dizziness, diarrhea, hypertension, anxiety and influenza. Overall, memantine in all formulations has a favorable safety/tolerability profile and is safe to use with cholinesterase inhibitors. Memantine ER has yet to be evaluated against conventionally dosed immediate-release memantine.

Validity and responsiveness to change of clinically derived MDS scales in Alzheimer disease outcomes research

This analysis assessed 3 subscales derived from the nursing home Minimum Data Set (MDS), the Cognitive Performance Scale (CPS), Depression Rating Scale (DRS), and Aggressive Behavior Scale (ABS), as outcome measures in clinical trials of long-term care residents with Alzheimer disease (AD). A total of 26 patients with moderate-to-severe AD and agitation/aggression enrolled in a trial of memantine were assessed using the Mini-Mental State Examination (MMSE), Neuropsychiatric Inventory Nursing Home Version (NPI-NH), and the Cohen-Mansfield Agitation Inventory (CMAI) administered by trained researchers. MDS data were collected as part of their standard clinical care. The MDS subscales correlated significantly with their corresponding research scales: CPS and MMSE (r = -0.57, P = .003); DRS and NPI-NH total (r = 0.42, P = .038); DRS and NPI-NH depression (r = 0.41, P = .04), and ABS and CMAI (r = 0.54, P = .004). DRS and ABS scores did not change significantly from baseline to 3 months though the NPI-NH and CMAI did, indicating limited sensitivity to change. This suggests that the MDS subscales measure comparable aspects of cognitive function and depressive and agitated/aggressive behavior as the MMSE, NPI-NH, and CMAI. However, this analysis also suggests that sensitivity to change of the DRS and ABS may be limited compared to the NPI-NH and CMAI. As these findings are preliminary, further research is needed to determine the utility of MDS scales in outcomes research.

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.

Test-retest reliability of memory task functional magnetic resonance imaging in Alzheimer disease clinical trials

OBJECTIVE

To examine the feasibility and test-retest reliability of encoding-task functional magnetic resonance imaging (fMRI) in mild Alzheimer disease (AD).

DESIGN

Randomized, double-blind, placebo-controlled study.

SETTING

Memory clinical trials unit.

PARTICIPANTS

We studied 12 patients with mild AD (mean [SEM] Mini-Mental State Examination score, 24.0 [0.7]; mean Clinical Dementia Rating score, 1.0) who had been taking donepezil hydrochloride for more than 6 months from the placebo arm of a larger 24-week study (n = 24, 4 scans on weeks 0, 6, 12, and 24, respectively).

INTERVENTIONS

Placebo and 3 face-name, paired-associate encoding, block-design blood oxygenation level-dependent fMRI scans in 12 weeks.

MAIN OUTCOME MEASURES

We performed whole-brain t maps (P < .001, 5 contiguous voxels) and hippocampal regions-of-interest analyses of extent (percentage of active voxels) and magnitude (percentage of signal change) for novel-greater-than-repeated face-name contrasts. We also calculated intraclass correlation coefficients and power estimates for hippocampal regions of interest.

RESULTS

Task tolerability and data yield were high (95 of 96 scans yielded favorable-quality data). Whole-brain maps were stable. Right and left hippocampal regions-of-interest intraclass correlation coefficients were 0.59 to 0.87 and 0.67 to 0.74, respectively. To detect 25.0% to 50.0% changes in week-0 to week-12 hippocampal activity using left-right extent or right magnitude with 80.0% power (2-sided α = .05) requires 14 to 51 patients. Using left magnitude requires 125 patients because of relatively small signal to variance ratios.

CONCLUSIONS

Encoding-task fMRI was successfully implemented in a single-site, 24-week, AD randomized controlled trial. Week 0 to 12 whole-brain t maps were stable, and test-retest reliability of hippocampal fMRI measures ranged from moderate to substantial. Right hippocampal magnitude may be the most promising of these candidate measures in a leveraged context. These initial estimates of test-retest reliability and power justify evaluation of encoding-task fMRI as a potential biomarker for signal of effect in exploratory and proof-of-concept trials in mild AD. Validation of these results with larger sample sizes and assessment in multisite studies is warranted.

Changes in nursing burden following memantine for agitation and aggression in long-term care residents with moderate to severe Alzheimer's disease: an open-label pilot study

BACKGROUND

Agitation and aggression are common neuropsychiatric symptoms of Alzheimer's disease (AD) with a negative impact on caregivers.

OBJECTIVE

The aim of the study was to determine whether changes in agitation and aggression would follow memantine treatment and, if so, be associated with changes in nursing burden in institutionalized patients with moderate to severe AD.

STUDY DESIGN

This was a 3-month open-label trial of memantine.

SETTING

The setting was two long-term care facilities.

PATIENTS

Thirty-one institutionalized patients with moderate to severe AD and significant behavioural and psychiatric symptoms were included in the study.

INTERVENTION

Memantine was titrated to a target dose of 10 mg twice daily.

MAIN OUTCOME MEASURE

Effectiveness was assessed by the change in the Neuropsychiatric Inventory-Nursing Home (NPI-NH) agitation/aggression subscale and Clinical Global Impression of Change (CGI-C) scale using the intent-to-treat population. To establish caregiver impact, the effect on nursing burden was measured by the Modified Nursing Care Assessment Scale (primary outcome). As a secondary analysis, the caregiver distress subscale of the NPI-NH was examined, as well as changes in as required (pro re nata [prn]) psychotropic medication use.

RESULTS

Twenty-four patients completed the study. A significant decrease in agitation and aggression (F-test with 3 and 90 degrees of freedom [F(3,90)] = 3.721, p = 0.014) was demonstrated following memantine, with 48% of patients improving (either much improved or minimally improved) on the CGI-C scale. In addition, nursing burden (t-test with 30 degrees of freedom [t(30)] = 3.02, p = 0.005), caregiver distress (F(3,90) = 4.125, p = 0.009) and the use of prn psychotropics decreased following memantine treatment (Z = -1.99, p = 0.046). Fourteen patients experienced at least one adverse event during memantine treatment. The most common adverse event associated with treatment was somnolence (n = 5).

CONCLUSION

The results of this study suggest that the decreased agitated and aggressive behaviour in institutionalized patients with moderate to severe AD following treatment with memantine was accompanied by improvements in nursing burden and decreased psychotropic use. These findings should be confirmed in a larger, controlled trial.

Solanezumab for Alzheimer's disease

INTRODUCTION

Alzheimer's disease (AD) is a debilitating neurodegenerative illness affecting over 35 million people worldwide. Solanezumab is a monoclonal antibody that binds to β-amyloid (Aβ), a protein that plays a key role in the pathogenesis of AD. The drug is currently being investigated in Phase III trials as a disease-modifying treatment for AD.

AREAS COVERED

This paper reviews literature on solanezumab that is available in PubMed from 2008 to 2010, other treatment trials in clinicaltrials.gov and published abstracts from conferences. The article also provides a discussion of the early trials of AN1792 and an overview of the immunotherapies currently in development. The authors provide the reader with a critical appraisal of the to-date clinical trial data on solanezumab and its implications for the broader field of immunotherapies for AD.

EXPERT OPINION

Solanezumab can neutralize soluble Aβ peptides, which may represent the more neurotoxic of the Aβ species. Phase II findings support the compound's safety, which has been a concern for some Aβ immunotherapies. Cerebrospinal and plasma biomarker changes with solanezumab treatment are encouraging. Results of the ongoing Phase III trials will be instrumental in determining the drug's clinical significance.

Managing the patient with dementia in long-term care

The majority of residents in a nursing home have some degree of dementia. The prevalence is commonly from 70% to 80% of residents. This article covers the following topics on caring for patients with dementia in long-term care: (1) the efficacy of cholinesterase inhibitors and memantine, (2) the optimal environment for maintenance of function in moderate dementia, (3) the treatment of depression and agitation, and (4) the evaluation and management of eating problems.

Memantine in moderate to severe Alzheimer's disease: an observational post-marketing study

Memantine is an N-methyl-D: -aspartate (NMDA) receptor antagonist, approved for the treatment of moderate to severe Alzheimer's disease (AD). We conducted a 4-month observational, post-marketing, Austrian study of memantine in 377 outpatients with moderate to severe AD. In this 'real-life' setting, memantine was well-tolerated, and produced benefits in cognition (Mini-Mental State Examination), activities of daily living (Activities of Daily Living score), and global function (Clinical Global Impression scale). Treatment effects were apparent in both pre-treated and treatment-naïve patient subgroups.

Switching cholinesterase inhibitors in older adults with dementia

BACKGROUND

Cholinesterase inhibitors (ChEIs) represent the mainstay of symptomatic treatment in Alzheimer's disease. Three medications belonging to this class are presently widely available. These agents differ in their individual mechanisms of action and pharmacokinetic properties. Switching ChEIs can be a reasonable option in cases of intolerance or lack of clinical benefit.

METHODS

A systematic literature search of switching ChEIs was conducted, and all studies specifically evaluating this issue were identified. Published consensus guidelines were also searched for recommendations on ChEI switching.

RESULTS

Eight clinical studies are summarized and discussed. All of these studies are open-label or retrospective and they cannot be readily compared because of heterogeneity in design, number of patients, agents used, and endpoints. Switching in most of these studies was done for both "lack of benefit" or "loss of response" after up to 29 months of treatment. Nevertheless, the majority of studies did not include individuals switched for lack of response after several years of treatment. Lack of satisfactory response or intolerance with the initial agent was not predictive of similar results with the second agent.

CONCLUSIONS

In light of these findings, we propose the following practical approach to switching ChEIs: (1) in the case of intolerance, switching to a second agent should be done only after the complete resolution of side-effects following discontinuation of the initial agent; (2) in the case of lack of efficacy, switching can be done overnight, with a quicker titration scheme thereafter; (3) switching ChEIs is not recommended in individuals who show loss of benefit several years after initiation of treatment.

Possible antidepressant effects and mechanisms of memantine in behaviors and synaptic plasticity of a depression rat model

Glutamatergic processes are strongly implicated in the pathophysiology and treatment of depression, including the antidepressant effects of N-methyl-D-aspartate (NMDA) receptor antagonists. This study was designed to see whether memantine, a noncompetitive NMDA antagonist, has antidepressant effects in behaviors and synaptic plasticity. Rats were randomly divided into control, stressed, and stressed+memantine groups. The animal model was established by chronic unpredictable stress. Memantine (20 mg/kg) was administrated i.p. for 21 days. Weight, sucrose consumption, water maze behavior and prefrontal cortical long-term potentiation (LTP) were measured, followed by immunohisotchemistry test of NR2B expression. Results showed that rats' weight and sucrose consumption were significantly lower in stressed group than those in control group, while the last time of sucrose consumption was improved by memantine. Rats in stressed group performed worse in reversal learning related stages, while rats in stressed+memantine group performed worse in spatial memory related stages. LTP test showed lower amplitude of field excitatory postsynaptic potential in prefrontal cortex in stressed group. Immunohistochemistry showed lower expression of NR2B receptor in prefrontal cortex in stressed group, and higher expression in hippocampus in stressed+memantine group. In conclusion, memantine in dose of 20 mg/kg improves the sucrose consumption, reversal learning and prefrontal cortical synaptic plasticity, but impairs spatial memory, which is probably due to different extent of up-regulating NR2B receptor expression in prefrontal cortex and hippocampus in stressed rats.

[Short evaluation of cognitive state in advanced stages of dementia: preliminary results of the Spanish validation of the Severe Mini-Mental State Examination]

INTRODUCTION

The cognitive assessment of patients with advanced dementia needs proper screening instruments that allow obtain information about the cognitive state and resources that these individuals still have. The present work conducts a Spanish validation study of the Severe Mini Mental State Examination (SMMSE).

MATERIAL AND METHODS

Forty-seven patients with advanced dementia (Mini-Cognitive Examination [MEC]<11) were evaluated with the Reisberg's Global Deterioration Scale, MEC, SMMSE and Severe Cognitive Impairment Profile scales.

RESULTS

All test items were discriminative. The test showed high internal (α=0.88), test-retest (0.64 to 1.00, P<.01) and between observers reliabilities (0.69-1.00, p<0.01), both for scores total and for each item separately. Construct validity was tested through correlations between the instrument and MEC scores (r=0.59, P<0.01). Further information on the construct validity was obtained by dividing the sample into groups that scored above or below 5 points in the MEC and recalculating their correlations with SMMSE. The correlation between the scores in the SMMSE and MEC was significant in the MEC 0-5 group (r=0.55, P<.05), but not in the MEC>5 group. Additionally, differences in scores were found in the SMMSE, but not in the MEC, between the three GDS groups (5, 6 and 7) (H=11.1, P<.05).

CONCLUSIONS

The SMMSE is an instrument for the assessment of advanced cognitive impairment which prevents the floor effect through an extension of lower measurement range relative to that of the MEC. From our results, this rapid screening tool and easy to administer, can be considered valid and reliable.

Drug delivery strategies for Alzheimer's disease treatment

INTRODUCTION

Current Alzheimer's disease (AD) therapy is based on the administration of the drugs donepezil, galantamine, rivastigmine and memantine. Until disease-modifying therapies become available, further research is needed to develop new drug delivery strategies to ensure ease of administration and treatment persistence.

AREAS COVERED

In addition to the conventional oral formulations, a variety of drug delivery strategies applied to the treatment of AD are reviewed in this paper, with a focus on strategies leading to simplified dosage regimens and to providing new pharmacological tools. Alternatives include extended release, orally disintegrating or sublingual formulations, intranasal or short- and long-acting intramuscular or transdermal forms, and nanotechnology-based delivery systems.

EXPERT OPINION

The advent of new research on molecular mechanisms of AD pathogenesis has outlined new strategies for therapeutic intervention; these include the stimulation of α-secretase cleavage, the inhibition of γ-secretase activity, the use of non-steroidal anti-inflammatory drugs, neuroprotection based on antioxidant therapy, the use of estrogens, NO synthetase inhibitors, and natural agents such as polyphenols. Unfortunately, these compounds might not help patients with end stage AD, but might hopefully slow or stop the disease process in its early stage. Nanotechnologies may prove to be a promising contribution in future AD drug delivery strategies, in particular drug carrier nano- or microsystems, which can limit the side effects of anti-Alzheimer drugs.

Prevention of dementia

Dementia is a neurological condition that is characterized by decline in multiple cognitive domains and is accompanied by a functional impairment. It is important to identify the factors that may delay the onset, slow the progression, or prevent cognitive decline. This review highlights the protective and risk factors of dementia, suggesting that physical activity, intellectual activity, and social engagement may reduce Alzheimer disease and cognitive decline and may be also helpful for enhancing quality of life.

Managing cognitive dysfunction through the continuum of Alzheimer's disease: role of pharmacotherapy

It has been shown that, during several years preceding the diagnosis of Alzheimer's disease there is a gradual cognitive decline with a continuum between the pre-dementia stage (still known as the prodromal stage but now included within the general concept of mild cognitive impairment [MCI]) and the other stages of the disease. In MCI, the use of cholinesterase inhibitors (ChEIs) is not associated with any delay in the onset of Alzheimer's disease or dementia. During the dementia stages, the three ChEIs (donepezil, galantamine and rivastigmine) are efficacious for mild to moderate Alzheimer's disease; therefore, monotherapy with a ChEI can be envisaged as initial treatment. Confirmation of the efficacy of ChEIs in the mild dementia stage is essentially based on the results from a single, randomized study carried out specifically among patients at this stage of severity. Memantine can represent an alternative to ChEIs in the moderate stage of Alzheimer's disease. At the severe stage of the disease, memantine and donepezil are currently indicated. Indeed, memantine has been approved by numerous drug regulatory agencies for use in severe stages of the disease, whereas donepezil has only been approved by the US FDA. There is currently insufficient evidence for recommending combination therapy in Alzheimer's disease.

Efficacy of memantine in PDD and DLB: an extension study including washout and open-label treatment

OBJECTIVE

This 30-week extension trial was a continuation of the first double-blind randomized controlled trial (RCT) to study memantine in dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD). The objective was to evaluate the presence of recurrence of symptoms upon drug withdrawal. Furthermore, the aim was to explore washout dynamics in order to inform clinical practice.

METHODS

Patients were enrolled from psychiatric, memory and neurological outpatient clinics in Norway, Sweden and the UK. The trial comprised a 4-week washout period and a 26-week open-label treatment period. Outcome measures were presence of recurrence of symptom upon drug withdrawal, Clinical Global Impression of Change (CGIC) and modified motor Unified Parkinson's Disease Rating Scale (UPDRS).

RESULTS

recurrence of symptoms occurred more frequently (p=0.04) in patients receiving memantine (58%) than in patients receiving placebo (25%). There was a significant global deterioration (p=0.0003) during washout within the memantine group as measured by CGIC. The patients seemed to recover during the open-label treatment, however these findings were non-significant.

CONCLUSIONS

The findings inform clinical practice that any possible memantine-associated benefits might be rapidly lost after drug withdrawal. The magnitude of deterioration suggests a symptomatic rather than a disease-modifying effect of the drug. Open-label results should merely be considered inspiration for future trials.

Activation of brain histaminergic neurotransmission: a mechanism for cognitive effects of memantine in Alzheimer's disease

We previously reported that some N-methyl-D-aspartate (NMDA)-receptor antagonists enhanced histamine neuron activity in rodents. Here, we have investigated the effects of memantine, an NMDA-receptor antagonist used for the treatment of Alzheimer's disease, on histaminergic neurotransmission. In vitro, memantine antagonized native NMDA receptors with a micromolar potency but had no effect at recombinant human histamine receptors. In vivo, a single administration of memantine increased histamine neuron activity, as shown by the 60% increase of tele-methylhistamine (t-MeHA) levels observed in the brain of mice. This increase occurred with an ED(50) of 0.3 ± 0.1 mg/kg, similar to that found on inhibition of ex vivo [(3)H]dizocilpine maleate (MK-801) binding (1.8 ± 1.3 mg/kg). Two days after pretreatment of mice with memantine at 5 mg/kg twice daily for 5 days, t-MeHA levels were enhanced by 50 ± 7% (p < 0.001), indicating a long-lasting activation of histamine neurons. Quantitative polymerase chain reaction analysis was used to explore genes involved in this persistent effect. H(3) receptor mRNAs were strongly increased, but the density of H(3) receptor binding sites was increased solely in hypothalamus (by 141 ± 24%). Up-regulations of brain-derived neurotrophic factor and NMDA-receptor 1 subunit mRNAs were also found but were restricted to hippocampus. mRNA expression of α7-nicotinic receptors remained unchanged in any region. Considering the well established cognitive effects of histamine neurons, the increase in brain t-MeHA levels after single or repeated administration of therapeutic doses of memantine suggests that the drug exerts its beneficial effects on cognitive deficits of Alzheimer's disease, at least partly, by activating histamine neurons.

World Federation of Societies of Biological Psychiatry (WFSBP) guidelines for the biological treatment of Alzheimer's disease and other dementias

OBJECTIVES

To define a practice guideline for biological treatment of dementia and to make transparent the development of the guideline connecting the original data with the resulting recommendations.

METHODS

This guideline includes pharmacologic treatment considerations for patients with Alzheimer's disease, vascular dementia, DLB, and fronto-temporal dementia. Studies were selected that represent double-blind placebo-controlled trials of at least 3 months duration in patients with a diagnosis of dementia according to accepted international diagnostic criteria (for example the NINCDS/ADRDA or NINDS/AIREN criteria). Moreover, to be included studies had to fulfill a restrictive set of methodological criteria. Original studies and not meta-analyses determined the evaluation and the development of recommendations.

RESULTS

Antidementia pharmaceuticals neither cure nor arrest the disease. A modest effect of improvement of symptoms compared with placebo can be observed. Antidementia pharmaceuticals show different efficacy and side effect profiles. The type of dementia, the individual symptom constellation and the tolerability should determine what medication should be used. There are hints that combination therapy of drugs with different therapeutic mechanisms might improve the efficacy. In treating neuropsychiatric symptoms (NPS), psychosocial intervention should be the treatment of first choice. Pharmaceuticals can only be recommended when psychosocial interventions is not adequate. However, even then the side effects of pharmaceuticals limit their use.

CONCLUSIONS

Depending on the diagnostic entity and the pathology treated different anti-dementia drugs can be recommended to improve symptoms. In the management of NPS, side effects limit the use of medications even when psychosocial interventions have failed. Thus, there is an urgent need to develop more efficacious medications for the treatment of dementia.

Current perspectives on pharmacotherapy of Alzheimer's disease

INTRODUCTION

Alzheimer's disease (AD) is a daunting public health threat that has prompted the scientific community's ongoing efforts to decipher the underlying disease mechanism, and thereafter, target this therapeutically. Although basic research in AD has made remarkable progress over the past two decades, currently available drugs can only improve cognitive symptoms temporarily; no treatment can reverse, stop, or even slow this inexorable neurodegenerative process. Numerous disease-modifying strategies targeting the production and clearance of Aβ, as well as modulation of abnormal aggregation of tau filaments, are currently in clinical trials .

AREAS COVERED

this review provides an overview of a wide array of therapeutic approaches under investigation, and the perspectives developed in the last 10 years.

EXPERT OPINION

While it is not possible to predict the success of any individual program, one or more are likely to prove effective. Indeed, it seems reasonable to predict that in the not-too-distant future, a synergistic combination of agents will have the capacity to alter the neurodegenerative cascade and reduce the global impact of this devastating disease. The scientific community must acknowledge that Alzheimer's disease is a complex multifactorial disorder, and thus a single target or pathogenic pathway is unlikely to be identified. The major aim should be to design ligands with pluripotent pharmacological activities.

The efficacy of licensed-indication use of donepezil and memantine monotherapies for treating behavioural and psychological symptoms of dementia in patients with Alzheimer's disease: systematic review and meta-analysis

BACKGROUND/AIMS

Behavioural and psychological symptoms of dementia (BPSD) in Alzheimer's disease (AD) greatly increase caregiver burden. The abilities of donepezil and memantine to manage BPSD within their licensed indications in AD were compared.

METHODS

A systematic review, random effects meta-analysis and Bucher indirect comparison were conducted.

RESULTS

Six randomised controlled studies (4 donepezil and 2 memantine) reported use within the licensed indication and had Neuropsychiatric Inventory (NPI) data suitable for meta-analysis. BPSD showed significant improvement with donepezil compared with placebo [weighted mean difference (WMD) in NPI -3.51, 95% confidence interval (CI) -5.75, -1.27], whereas this was not the case for memantine (WMD -1.65, 95% CI -4.78, 1.49). WMD in NPI for donepezil versus memantine favoured donepezil but was not statistically significant (-1.86, 95% CI -5.71, 1.99; p = 0.34).

CONCLUSION

Within its licensed indication, donepezil is efficacious for the management of BPSD in AD compared with placebo.

Open-label study of the short-term effects of memantine on FDG-PET in frontotemporal dementia

BACKGROUND

Memantine has shown effects on cortical metabolism in Alzheimer's disease (AD), and the mechanism of action may not be specific to AD alone. We hypothesized that participants with frontotemporal dementia taking memantine would show an increased cortical metabolic activity in frontal regions, temporal regions, or in salience network hubs.

METHODS

Sixteen participants with behavioral or language variant frontotemporal dementia syndromes (FTD) were recruited from tertiary FTD clinics and treated with memantine hydrochloride 10 mg twice daily in this fixed-dose, open-label pilot study. The primary endpoint was enhancement of cortical metabolic activity after 7-8 weeks of treatment. Secondary endpoints were measures of mood and behavior disturbance, frontal executive function, and motor disturbance.

RESULTS

Voxel-wise parametric image analysis of positron emission tomography (PET) data from seven behavioral variant FTD patients, eight semantic dementia patients, and one progressive nonfluent aphasia patient, of mean age 64.3 years, mean duration of illness 4.25 years, and baseline mean sum of boxes Clinical Dementia Rating score 6.59, revealed an increase in [(18)F]-fluorodeoxyglucose (FDG) normalized metabolic activity in bilateral insulae and the left orbitofrontal cortex (P < 0.01). The increase on FDG-PET did not correlate with changes on behavioral inventories. Post hoc analysis indicated that semantic dementia participants drove this finding.

CONCLUSION

This open-label clinical PET study suggests that memantine induces an increase in metabolism in the salience network in FTD. A placebo-controlled follow-up study is warranted.