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Serge Gauthier

Publications and source records attributed to Serge Gauthier.

36 records · Page 2Linked to original sources

Treatment of vascular dementia--evidence from clinical trials with cholinesterase inhibitors.

Cerebrovascular disease (CVD), as well as secondary ischemic brain injury from cardiovascular disease, are common causes of dementia and cognitive decline in the elderly. In addition, CVD frequently contributes to cognitive loss in patients with Alzheimer's disease (AD). Progress in understanding the pathogenetic mechanism involved in vascular cognitive impairment (VCI) and vascular dementia (VaD) has resulted in promising treatments of these conditions. Cholinergic deficits in VaD are due to ischemia of basal forebrain nuclei and of cholinergic pathways and can be treated with the use of the cholinesterase inhibitor agents used in AD. Controlled clinical trials with donepezil, galantamine and rivastigmine in VaD, as well as in patients with AD plus CVD, have demonstrated improvements in cognition, behavior and activities of daily living.

Aged↗

Emerging therapies for vascular dementia and vascular cognitive impairment.

BACKGROUND: Cerebrovascular disease (CVD) and ischemic brain injury secondary to cardiovascular disease are common causes of dementia and cognitive decline in the elderly. CVD also contributes to cognitive loss in Alzheimer disease (AD). SUMMARY: Progress in understanding vascular cognitive impairment (VCI) and vascular dementia (VaD) has resulted in promising symptomatic and preventive treatments. Cholinergic deficits in VaD due to ischemia of basal forebrain nuclei and cholinergic pathways can be treated with cholinesterase inhibitors used in AD. Controlled clinical trials with donepezil and galantamine in patients with VaD, as well as in patients with AD plus CVD, have demonstrated improvement in cognition, behavior, and activities of daily living. The N-methyl-D-aspartate receptor antagonist memantine stabilized progression of VaD compared with placebo. Primary and secondary stroke prevention, in particular with control of hypertension and hyperlipidemia, can decrease VaD incidence. CONCLUSIONS: From a public health viewpoint, recognition of VCI before the development of dementia and correction of vascular burden on the brain may lead to a global decrease of incident dementia.

Carbamates↗

Mild cognitive impairment can be distinguished from Alzheimer disease and normal aging for clinical trials.

BACKGROUND: Mild cognitive impairment (MCI) represents a transitional state between the cognitive changes of normal aging and very early dementia and is becoming increasingly recognized as a risk factor for Alzheimer disease (AD). The Memory Impairment Study (MIS) is a multicenter clinical trial in patients with MCI designed to evaluate whether vitamin E or donepezil is effective at delaying the time to a clinical diagnosis of AD. OBJECTIVE: To describe the baseline characteristics of patients with MCI recruited for the MIS and compare them with those of elderly controls and patients with AD in another clinical trial. DESIGN: Descriptive and comparative study of patients with MCI participating in a multicenter clinical trial. SETTING: Memory disorder centers in the United States and Canada. PATIENTS: A total of 769 patients with MCI, 107 cognitively normal elderly controls, 122 patients with very mild AD (Clinical Dementia Rating [CDR] 0.5), and 183 patients with mild AD (CDR 1.0) were evaluated. Patients in the MIS met operational criteria for amnestic MCI. Controls were recruited in parallel with the MCI group, underwent the same assessments, and had a CDR of 0. MAIN OUTCOME MEASURES: Clinical, neuropsychologic, functional, neuroimaging, and genetic measures. RESULTS: Mean +/- SD Alzheimer's Disease Assessment Scale-Cognitive Subscale scores were 5.6 +/- 3.3 for controls, 11.3 +/- 4.4 for patients with MCI, 18.0 +/- 6.2 for the AD CDR 0.5 group, and 25.2 +/- 8.8 for the AD CDR 1.0 group. Compared with controls, patients with MCI were most impaired on memory tasks, with less severe impairments in other cognitive domains. Patients with MCI were more likely than controls but less likely than patients with AD to carry the apolipoprotein E epsilon4 allele. Patients with MCI had hippocampal volumes that were intermediate between those of controls and patients with AD. CONCLUSIONS: Patients with MCI had a predominant memory impairment with relative sparing of other cognitive domains and were intermediate between clinically normal individuals and patients with AD on cognitive and functional ratings. These results demonstrate the successful implementation of operational criteria for this unique group of at-risk patients in a multicenter clinical trial.

Aged↗

Dementia with Lewy bodies.

Dementia with Lewy bodies (DLB) is the second commonest cause of neurodegenerative dementia in older people. It is part of the range of clinical presentations that share a neuritic pathology based on abnormal aggregation of the synaptic protein alpha-synuclein. DLB has many of the clinical and pathological characteristics of the dementia that occurs during the course of Parkinson's disease. Here we review the current state of scientific knowledge on DLB. Accurate identification of patients is important because they have specific symptoms, impairments, and functional disabilities that differ from those of other common types of dementia. Severe neuroleptic sensitivity reactions are associated with significantly increased morbidity and mortality. Treatment with cholinesterase inhibitors is well tolerated by most patients and substantially improves cognitive and neuropsychiatric symptoms. Clear guidance on the management of DLB is urgently needed. Virtually unrecognised 20 years ago, DLB could within this decade be one of the most treatable neurodegenerative disorders of late life.

Alzheimer Disease↗

Treatment of vascular dementia-evidence from clinical trials with cholinesterase inhibitors.

Cerebrovascular disease (CVD), as well as secondary ischemic brain injury from cardiovascular disease, are common causes of dementia and cognitive decline in the elderly. Also, CVD frequently contributes to cognitive loss in patients with Alzheimer's disease (AD). Progress in understanding the pathogenetic mechanism involved in vascular cognitive impairment and vascular dementia (VaD) has resulted in promising treatments of these conditions. Cholinergic deficits in VaD are due to ischemia of basal forebrain nuclei and of cholinergic pathways and can be treated with the use of the cholinesterase inhibitors used in AD. Controlled clinical trials with donepezil, galantamine, and rivastigmine in VaD, as well as in patients with AD plus CVD, have demonstrated improvement in cognition, behavior and activities of daily living.

Acetylcholinesterase↗

Expression of melanotransferrin isoforms in human serum: relevance to Alzheimer's disease.

Levels of soluble melanotransferrin in serum have been reported to be higher in patients with Alzheimer's disease than in control subjects. The present study investigated melanotransferrin in human body fluids in the light of these findings. To clarify the correlation between melanotransferrin and Alzheimer's disease, the melanotransferrin content was determined by non-reducing, denaturing SDS/PAGE and Western blotting. Under these conditions, serum melanotransferrin migrated at 79 and 82 kDa. Melanotransferrin antigenicity and the relative proportions of the two forms were very sensitive to factors that altered its conformation, including disulphide bridges, pH and bivalent cations. Serum melanotransferrin levels were not significantly different between control subjects and patients with Alzheimer's disease using whole serum, EDTA-supplemented serum or serum immunoglobulin-depleted by Protein G-Sepharose and enriched by affinity precipitation with the lectin from Asparagus pea. Glycosylated forms of serum melanotransferrin bound to Asparagus lectin manifested similar patterns on two-dimensional gel electrophoresis in samples from controls and Alzheimer's disease subjects. Melanotransferrin was also present in saliva and at a high level in urine, but contents were similar in controls and patients with Alzheimer's disease. Together, these results demonstrate that serum melanotransferrin exists in various conformations depending on the binding of bivalent cations or following post-translational modification. These data also indicate that human serum melanotransferrin levels are unchanged in subjects with Alzheimer's disease.

Alzheimer Disease↗

Vascular cognitive impairment.

Cerebrovascular disease is the second most common cause of acquired cognitive impairment and dementia and contributes to cognitive decline in the neurodegenerative dementias. The current narrow definitions of vascular dementia should be broadened to recognise the important part cerebrovascular disease plays in several cognitive disorders, including the hereditary vascular dementias, multi-infarct dementia, post-stroke dementia, subcortical ischaemic vascular disease and dementia, mild cognitive impairment, and degenerative dementias (including Alzheimer's disease, frontotemporal dementia, and dementia with Lewy bodies). Here we review the current state of scientific knowledge on the subject of vascular brain burden. Important non-cognitive features include depression, apathy, and psychosis. We propose use of the term vascular cognitive impairment, which is characterised by a specific cognitive profile involving preserved memory with impairments in attentional and executive functioning. Diagnostic criteria have been proposed for some subtypes of vascular cognitive impairment, and there is a pressing need to validate and further refine these. Clinical trials in vascular cognitive impairment are in their infancy but support the value of therapeutic interventions for symptomatic treatment.

Cerebrovascular Disorders↗

The Consortium to Investigate Vascular Impairment of Cognition: methods and first findings.

BACKGROUND: The Consortium to Investigate Vascular Impairment of Cognition (CIVIC) is a Canadian, multi-centre, clinic-based prospective cohort study of patients with Vascular Cognitive Impairment (VCI). We report its organization and the impact of diagnostic criteria on the study of VCI. METHODS: Nine memory disability clinics enrolled patients and recorded their usual investigations and care. A case report form included all vascular dementia (VaD) individual criteria for each of four sets (National Institute of Neurological Disorders and Stroke (NINDS-AIREN), Alzheimer's Disease Diagnostic Treatment Centers (ADDTC), the ICD-10 Classification of Mental and Behavioural Disorders (ICD-10), and the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV)) of consensus-based diagnostic criteria and for the Hachinski Ischemia Score (HIS). Investigators, having completed the case report form, were asked to make a clinical judgement about the cognitive diagnosis based on the best available information, including neuroimaging. RESULTS: Of 1,347 patients (mean age 72 years; 56% women), 846 (63%) were diagnosed with dementia and 324 (24%) were diagnosed with VCI. The proportion of patients diagnosed with VaD by the diagnostic criteria was: 23.9% (n = 322) by DSM-IV, 10.2% (n = 137) by HIS, 4.3% (n = 58) by ICD-10, 3.8% (n = 51) by ADTCC, and 3.6% (n = 48) by NINDS-AIREN. Judged against a clinical diagnosis of VaD, the sensitivity/specificity of each was: DSM-IV (0.77/0.80); HIS (0.41/0.92); ICD-10 (0.29/0.98); ADTCC (0.24/0.98); NINDS-AIREN (0.42/0.995). Compared with a clinical diagnosis of VCI, sensitivities were lower for the diagnostic criteria, reflecting the exclusion of patients who did not have dementia. CONCLUSIONS: Consensus-based criteria for VaD omit patients who do not meet dementia criteria that are modeled on Alzheimer's disease. Even for patients who do, the proportion identified with VaD varies widely. Criteria based on empirical analyses need to be developed and validated.

Adult↗

Does vascular MCI progress at a different rate than does amnestic MCI?

This article reviews the evidence available from natural history studies and randomized clinical trials (RCT) concerning what is now coined as amnestic MCI and vascular MCI and will answer the question about the similarity and difference of their progression toward dementia. The issues to be resolved prior to the use of a survival design for conversion from vascular MCI to dementia will be discussed.

Aged↗

Efficacy of donepezil on maintenance of activities of daily living in patients with moderate to severe Alzheimer's disease and the effect on caregiver burden.

OBJECTIVES: This study investigated the efficacy of donepezil treatment on activities of daily living (ADLs) and social functioning in patients with moderate to severe Alzheimer's disease (AD) and the possible benefits of this treatment on caregiving time and stress levels. DESIGN: Randomized, double-blind, placebo-controlled, multinational study. SETTING: Patients resided in the community or in assisted living facilities who did not require skilled 24-hour nursing care. PARTICIPANTS: Two hundred ninety patients with moderate to severe AD (baseline standardized Mini-Mental State Examination score of 5-17). INTERVENTION: Donepezil (5 mg/d for 4 weeks and 10 mg/d per clinician's judgment thereafter) or placebo for 24 weeks. MEASUREMENTS: ADLs were assessed using the Disability Assessment for Dementia (DAD), the modified instrumental activities of daily living (IADL) scale (IADL+), and the modified Physical Self Maintenance Scale (PSMS+). Caregiver time spent assisting patients with basic and instrumental ADLs was recorded as part of the IADL+ and PSMS+ scales. Patients' social behavior was evaluated through the use of a caregiver diary that captured observations of patients' motivation, interactions, and engagement. Caregivers were evaluated for their levels of caregiver stress with a modified, multiple-item Caregiver Stress Scale (CSS). For each outcome measure, the mean change from baseline at Week 24 using a last observation carried forward (LOCF) analysis was calculated. RESULTS: IADL+ and PSMS+ mean change from baseline scores for donepezil-treated patients showed a slower decline during the study than placebo-treated patients (Week 24 LOCF mean treatment differences: IADL+ = 6.83, P <.0001; PSMS+ = 1.32, P =.0015). Significant differences between the groups in favor of donepezil were observed on the DAD for instrumental and basic ADLs and on the three components required for the completion of each ADL: initiation, planning and organization, and effective performance. At baseline, caregivers of patients treated with donepezil (n = 141) did not differ significantly from caregivers of patients treated with placebo (n = 146) with respect to demographics or mean total scores on the CSS. At Week 24 LOCF, the overall distribution of caregiver ratings on each of the three caregiver diary items favored donepezil-treated patients over placebo-treated patients (P <.005). At Week 24 LOCF, mean change from baseline scores for CSS total and individual domain scores (all domains except caregiving competence, personal gain, and management of distress) were better for caregivers of donepezil-treated patients than for those of placebo-treated patients (CSS total, mean treatment difference = 1.82). Caregivers of donepezil-treated patients reported spending less time assisting with ADLs than caregivers of placebo-treated patients (mean difference = 52.4 min/d). CONCLUSION: Donepezil demonstrated a significantly slower decline than placebo in instrumental and basic ADLs in these patients with moderate to severe AD. The ADL benefits in AD patients treated with donepezil were associated with less caregiving time and lower levels of caregiver stress.

Activities of Daily Living↗

Alzheimer's disease: the pharmacological pathway.

The current pharmacological treatment of Alzheimer's disease (AD) comes down to four marketed drugs (tacrine, donepezil, rivastigmine and galantamine) all of which are cholinesterase inhibitors, conforming to the cholinergic hypothesis. The future is clearly directed at new biological targets closely linked to the pathophysiology of the disease and more precisely, the pathological hallmark of AD which includes widespread neuronal degeneration, neuritic plaques containing beta-amyloid and tau-rich neurofibrillary tangles. For clinicians, this means that new curative drugs will have to be prescribed early in the course of the disease. This review describes the main entry pathways for drug discovery in AD: (1) supplementation therapy, (2) anti-apoptotic compounds, (3) substances with a mitochondrial impact, (4) anti-amyloid substances, (5) anti-protein aggregation and (6) lipid-lowering drugs. The rapidity at which these compounds will be at our disposal is highly dependent on the policy of the pharmaceutical companies.

Alzheimer Disease↗

Strategies for continued successful treatment of Alzheimer's disease: switching cholinesterase inhibitors.

Cholinesterase (ChE) inhibitors represent the standard therapeutic approach to the treatment of Alzheimer's disease (AD). However, a proportion of patients experience lack or loss of therapeutic benefit with an initial agent, or discontinue due to safety/tolerability issues. In many instances, no alternative treatment is offered once the initial agent has been stopped. Thus, for many patients, the total duration of treatment is relatively short in comparison with the chronic nature of AD. Switching medications is a common therapeutic strategy within many drug classes across many clinical areas following a lack/loss of efficacy or safety/tolerability problems, and is also an increasingly important concept in the management of AD with ChE inhibitors. A number of open-label studies, where patients were switched from donepezil to rivastigmine, have indicated that approximately 50% of patients experiencing a lack/loss of efficacy with donepezil (a selective acetylcholinesterase [AChE] inhibitor) respond to subsequent treatment with rivastigmine (a dual AChE and butyrylcholinesterase inhibitor). In these studies, rivastigmine was well tolerated, and the occurrence of safety/tolerability problems with donepezil was not predictive of similar problems with rivastigmine. In the summer of 2002, leading neurologists and psychiatrists attended a medical experts meeting to discuss the clinical importance of switching ChE inhibitors in AD. The expert panel examined available clinical data, shared clinical experiences, and discussed current clinical guidelines for switching. The panel also aimed to reach consensus on 'whom to switch', 'when to switch' and 'how to switch'. The key findings from that meeting are reported in this review.

Alzheimer Disease↗

Efficacy of galantamine in probable vascular dementia and Alzheimer's disease combined with cerebrovascular disease: a randomised trial.

BACKGROUND: Vascular dementia is the second commonest form of dementia, and vascular factors contribute to the development of dementia in many patients with Alzheimer's disease. Galantamine amplifies the acetylcholine response by inhibiting acetylcholinesterase and modulating nicotinic receptors. It has shown broad, sustained benefits in patients with Alzheimer's disease. We investigated the effects of galantamine in patients with a diagnosis of probable vascular dementia or Alzheimer's disease combined with cerebrovascular disease. METHODS: Eligible patients were randomly assigned galantamine 24 mg/day (n=396) or placebo (n=196) in a multicentre, double-blind, 6-month trial. Primary endpoints were cognition (Alzheimer's disease assessment scale, cognitive subscale [ADAS-cog]) and global functioning (clinician's interview-based impression of change plus caregiver input [CIBIC-plus]). Secondary endpoints included assessments of activities of daily living and behavioural symptoms. Patients were monitored for adverse events. Analyses were on the basis of observed case or last observation carried forward. FINDINGS: Galantamine showed greater efficacy than placebo on ADAS-cog (galantamine change -1.7 [SE 0.4] vs placebo 1.0 [0.5]; treatment effect 2.7 points; p<0.0001) and CIBIC-plus (213 [74%] vs 95 [59%] patients remained stable or improved, p=0.0001). Activities of daily living and behavioural symptoms were also significantly improved compared with placebo (p=0.002 and p=0.016, respectively). Galantamine was well tolerated. INTERPRETATION: Galantamine showed a therapeutic effect on all key areas of cognitive and non-cognitive abilities in this group of dementia patients.

Aged↗

Efficacy of donepezil on behavioral symptoms in patients with moderate to severe Alzheimer's disease.

OBJECTIVE: This subanalysis of a large, double-blind, placebo-controlled trial examined the prevalence of behavioral symptoms in moderate to severe Alzheimer's disease (AD), and the effect of treatment with donepezil. METHODS: Two hundred ninety patients with moderate to severe AD (standardized Mini-Mental State Examination scores 5-17) were randomized to receive 24 weeks of once-daily doses of donepezil 5 mg/day for 28 days, and 10 mg/day thereafter per the clinician's judgment (n = 144), or placebo (n = 146). The outcome measure of interest was the 12-item Neuropsychiatric Inventory (NPI). RESULTS: Baseline demographics were similar between the treatment groups. Least squares mean (+/- SE) baseline NPI 12-item total scores were 19.55 +/- 1.48 and 19.30 +/- 1.45, respectively. At baseline, the most common symptoms were apathy/indifference (67%), aberrant motor behavior (53%), depression/dysphoria (52%), anxiety (49%), and agitation/aggression (45%). NPI individual item change from baseline scores at Week 24 using a last observation carried forward (LOCF) analysis showed benefits with donepezil treatment compared with placebo for all items, with significant treatment differences for depression/dysphoria, anxiety, and apathy/indifference (p < .05). Symptoms present at baseline that improved significantly for donepezil- compared with placebo-treated patients at Week 24 LOCF included anxiety, apathy/indifference, and irritability/lability (p < .05). When patients who were not receiving psychoactive medications at baseline were analyzed separately, significant improvements in NPI (continued) 12-item total score were observed with donepezil compared with placebo at most visits and at Week 24 LOCF (p < .05). CONCLUSIONS: Behavioral symptoms of the magnitude observed in this moderate to severe AD population improved with donepezil.

Aged↗

Galantamine demonstrates efficacy and safety in elderly patients with Alzheimer disease.

Alzheimer disease (AD) treatment guidelines state that cholinergic agents are not cost-effective in patients with more severe disease. Because many physicians may deem an older patient unlikely to respond to treatment, older AD patients may remain untreated. Galantamine (Reminyl), a novel cholinergic agent, is effective in mild to moderate AD. This post hoc analysis of pooled phase III galantamine clinical trials was designed to assess whether older (> or =80 years) and younger (< or =79 years) AD patients experience similar benefits with galantamine based on changes in the ADAS-cog and CIBIC-plus. Mean ADAS-cog scores for older patients treated with galantamine 24 mg/day significantly improved versus baseline and versus placebo at month 3. Cognitive improvement was maintained versus placebo at month 6; the ADAS-cog score for placebo patients dropped below baseline at month 6. Change in CIBIC-plus for galantamine was significantly different from placebo at months 5 to 6. Mean ADAS-cog score in older patients taking galantamine for 12 months remained above baseline. The score for patients taking placebo for 6 months before switching to galantamine did not differ significantly from baseline at 12 months but was lower than in patients receiving galantamine for 12 months. Incidence of adverse events in patients > 80 years was similar to that in the overall study population. Galantamine maintained cognitive and global function in patients > 80 years with mild to moderate AD for at least 5 to 6 months and cognitive efficacy for 12 months. Prescribing approved therapies such as galantamine for older patients with AD is recommended.

Age Factors↗