Search PubMed⌕ Search

Biomedical subjects

Serge Gauthier

Publications and source records attributed to Serge Gauthier.

At least 19 recordsLinked to original sources
PubMed2006

Disease progression in vascular cognitive impairment: cognitive, functional and behavioural outcomes in the Consortium to Investigate Vascular Impairment of Cognition (CIVIC) cohort study.

BACKGROUND AND PURPOSE: Empirical studies to clarify the outcomes in Vascular Cognitive Impairment (VCI) are needed. We compared cognitive, functional, and behavioural outcomes in patients with VCI to patients with no cognitive impairment (NCI), and Alzheimer's disease (AD). METHODS: Secondary analysis of the Consortium to Investigate Vascular Impairment of Cognition (CIVIC), a multi-centre Canadian memory clinic 30-month cohort study. RESULTS: Of 1347 patients, 938 were eligible for follow-up, of whom 239 (24.5%) were lost and 29 (3%) had died. Of the remaining 697 patients, 125 had NCI, 229 had VCI, and 343 had AD at baseline. Compared to people with NCI, of whom 20-40% showed progression based on cognitive and functional measures, those with VCI were more likely to progress (50-65%), as were people with AD (50-80%) (p<0.01). More people with VCI showed progression of affective symptoms (30%) than those with NCI (12%) or AD (15% p<0.01). Progression of impaired judgment (rated clinically) in VCI (15%) was similar to AD (11%) but more common than in NCI (4%, p<0.01). CONCLUSIONS: Most people with VCI show readily detectable progression by 30 months. Depressive symptoms were more common and more progressive in VCI than in Alzheimer's disease, whereas clinical evidence of progressive executive dysfunction was common in both AD and VCI.

Aged↗
PubMed2006

Recognition and management of neuropsychiatric complications in Parkinson's disease.

Parkinson's disease is primarily considered a motor disease characterized by rest tremor, rigidity, bradykinesia and postural disturbances. However, neuropsychiatric complications, including mood and anxiety disorders, fatigue, apathy, psychosis, cognitive impairment, dementia, sleep disorders and addictions, frequently complicate the course of the illness. The pathophysiologic features of these complications are multifaceted and include neuropathophysiologic changes of a degenerative disease, exposure to antiparkinsonian treatments and emotional reactions to having a disabling chronic illness. Changes in mental status have profound implications for the well-being of patients with Parkinson's disease and of their caregivers. Treatment is often efficacious but becomes a challenge in advanced stages of Parkinson's disease. In this article, we review the key clinical features of neuropsychiatric complications in Parkinson's disease as well as what is known about their epidemiologic characteristics, risk factors, pathophysiologic features and management.

Cognition Disorders↗
PubMed2006

Improvement of episodic memory in persons with mild cognitive impairment and healthy older adults: evidence from a cognitive intervention program.

The efficacy of cognitive training was assessed in persons with mild cognitive impairment (MCI) and persons with normal cognitive aging. Forty-seven participants were included in this study: 28 with MCI and 17 controls. Twenty-one participants received intervention (20 MCI and 9 controls) and 16 participants (8 MCI and 8 controls) received no intervention (waiting-list group). The intervention focused on teaching episodic memory strategies. Three tasks of episodic memory (list recall, face-name association, text memory) were used as primary outcome measures. Results were analyzed using analyses of variance. The intervention effect (pre- and post-intervention difference) was significant on two of the primary outcome measures (delayed list recall and face-name association). A significant pre-post-effect was also found on measures of subjective memory and well-being. There was no improvement in the performance of groups of individuals with MCI and normal elderly persons who did not receive the intervention. These results suggest that persons with MCI can improve their performance on episodic memory when provided with cognitive training.

Aged↗
PubMed2006

Mild cognitive impairment.

Mild cognitive impairment is a syndrome defined as cognitive decline greater than expected for an individual's age and education level but that does not interfere notably with activities of daily life. Prevalence in population-based epidemiological studies ranges from 3% to 19% in adults older than 65 years. Some people with mild cognitive impairment seem to remain stable or return to normal over time, but more than half progress to dementia within 5 years. Mild cognitive impairment can thus be regarded as a risk state for dementia, and its identification could lead to secondary prevention by controlling risk factors such as systolic hypertension. The amnestic subtype of mild cognitive impairment has a high risk of progression to Alzheimer's disease, and it could constitute a prodromal stage of this disorder. Other definitions and subtypes of mild cognitive impairment need to be studied as potential prodromes of Alzheimer's disease and other types of dementia.

Aged↗
PubMed2006

Progress in clinical neurosciences: Canadian guidelines for the development of antidementia therapies: a conceptual summary.

The magnitude of the problems faced by an aging Canadian society has been clearly identified. Perhaps the single most important problem is the increasing incidence of dementia. Alzheimer's disease (AD) accounts for 50-60% of the dementias in later life within a spectrum of other contributing dementias. Regulatory approval has been given to Acetylcholinesterase inhibitors for the symptomatic treatment of mild to moderate AD, and conditional approval to memantine for the symptoms of moderate to severe AD. There has been no regulatory approval for the treatment of the degenerative dementias beyond AD. The very rapid progress in the past decade in biotechnology and in the molecular biology of the dementias is supporting a new generation of innovative treatment strategies that will more directly target the underlying disease pathogenic mechanisms. Such treatments will foreseeably include immunotherapies, anti-aggregants that may prevent misfolding and deposition of proteins, and neuroregenerative interventions. These Guidelines follow the 2nd Canadian Conference on the Development of Antidementia Therapies, held in 2004, which covered a range of design, methodological and ethical issues facing clinical researchers and regulatory authorities. They are intended to provide a common point of reference and guidance in Canada for therapeutic development of the dementias.

Canada↗
PubMed2006

Memory for gist and detail information in Alzheimer's disease and mild cognitive impairment.

Two experiments examined different forms of gist and detail memory in people with Alzheimer's disease (AD) and those with amnestic mild cognitive impairment (MCI). In Experiment 1, 14 AD, 14 MCI, and 22 control participants were assessed with the Deese-Roediger-McDermott paradigm. Results indicated that false recognition of nonstudied critical lures (gist memory) was diminished in the AD compared with the MCI and control groups; the two latter cohorts performed similarly. In Experiment 2, 14 AD, 20 MCI, and 26 control participants were tested on a text memory task. Results revealed that recall of both macropropositions (gist information) and micropropositions (detail information) decreased significantly in AD and in MCI as compared with control participants. This experiment also revealed that the impairment was comparable between gist and detail memory. In summary, the results were consistent across experiments in the AD but not in the MCI participants. The discrepancy in MCI participants might be explained by differences in the degree of sensitivity of the experimental procedures and/or by the differences in the cognitive processes these procedures assessed.

Adult↗
PubMed2006

REM sleep behavior disorder and REM sleep without atonia in probable Alzheimer disease.

STUDY OBJECTIVE: To determine the frequency of rapid eye movement (REM) sleep behavior disorder (RBD) and REM sleep without atonia among patients with Alzheimer disease and control subjects. DESIGN: Overnight polysomnography. SETTINGS: Sleep laboratory. PATIENTS: Fifteen patients with probable Alzheimer disease (mean age +/-SD, 70.2+/-5.6) and 15 age-matched healthy control subjects (mean age +/- SD, 67.9 +/-5.4). INTERVENTION: N/A. RESULTS: Four patients with Alzheimer disease presented REM sleep with-out atonia. One of these patients had all the polysomnographic features of RBD, including behavioral manifestations during REM sleep. CONCLUSION: RBD is rare, but REM sleep without atonia is relatively fre-quent in patients with probable Alzheimer disease, a tauopathy.

Aged↗
PubMed2006

Reliability and validity of the Safety Assessment Scale for people with dementia living at home.

BACKGROUND: With the recent funding changes in health care services, more seniors with dementia are cared for in their homes and the nature of their condition puts them at higher risk for accidents and injuries. PURPOSE: The Safety Assessment Scale (SAS) was developed for use by community healthcare providers to evaluate and lower the risk of accidents, provide recommendations to family caregivers and enhance case management. Method. The scale was assessed in terms of the reliability as well as content, criterion and construct validity with 176 community-residing people with dementia in Quebec, Alberta and British Columbia. The Safety Assessment Scale was validated in French and English. RESULTS: The SAS demonstrated an excellent test-retest (ICC=.91) and inter-rater (ICC=.88) reliability. Results for validity were also extremely good. PRACTICE IMPLICATIONS: The scale is available in French and English. The short version of the SAS is a screening tool and the longer version provides an in-depth evaluation of safety and intervention planning. The SAS can be used by a variety of health care professionals who work with individuals who have dementia.

Accidents, Home↗
PubMed2006

A large, naturalistic, community-based study of rivastigmine in mild-to-moderate AD: the EXTEND Study.

BACKGROUND: Previous studies in Alzheimer's Disease (AD) suggest a benefit from switching from one cholinesterase (ChE) inhibitor to another in the event of treatment failure on the index agent. This observational, open-label study sought to evaluate the efficacy of the ChE inhibitor rivastigmine on cognition, functional autonomy and behavior in patients with mild-to-moderate AD previously treated with other ChE inhibitors (switched patients) as well as in those previously ChE-inhibitor-naive (de novo users). METHODS: Patients were eligible for a switch if they experienced a lack or loss of efficacy or had experienced intolerance to prior ChE inhibitor therapy. Rivastigmine was initiated at a dose of 1.5 mg b.i.d. and titration was done as per standard medical practice. Efficacy was assessed using the mini-mental state examination (MMSE) and an abbreviated version of the Clinician's Global Impression of Change (CGI-C) at Month 3 and Month 6. Caregiver burden was also assessed at Month 6 using a self-rated scale. RESULTS: Overall, 2633 subjects were enrolled in this study. The mean MMSE improved from 20.6 at baseline to 21.5 at Month 6. More patients improved than deteriorated on every domain of the CGI-C. Caregivers felt less burdened after the 6 month evaluation period. Efficacy parameters demonstrated favorable results for both de novo and switched patients, but more so in the first group. LIMITATIONS: Open-label studies have an inherent potential for bias by both the caregiver and the physician. In this study, there was also a large percentage of missing patient records for each of the follow-up visits (Months 3 and 6). CONCLUSIONS: Patients with mild-to-moderate AD switched from previous ChE inhibitor therapy to rivastigmine can obtain measurable benefits, although the treatment effect may be less than in de novo patients. Further research into switching cholinesterase inhibitors is warranted.

Aged↗
PubMed2006

Cognitive dysfunctions in schizophrenia: potential benefits of cholinesterase inhibitor adjunctive therapy.

OBJECTIVE: In schizophrenia, cognitive dysfunctions commonly affect attention, memory and executive function, interfere with functional outcome and remain difficult to treat. Previous studies have implicated the cholinergic system in cognitive functioning. In Alzheimer's disease, cholinergic agonists have shown modest clinical benefits on cognitive and behavioural symptoms. Impaired cholinergic activity might also be involved in schizophrenia. Hence the role of cholinesterase inhibitors (ChEI) as adjunctive therapy is under study. We aimed to review the literature and evaluate the overall effectiveness of ChEI adjunctive therapy for the management of cognitive dysfunctions in schizophrenia. METHODS: We conducted a computer-based search using PubMed (up to February 15, 2006) and ISI Web of Science (conference proceeding abstracts from January 2003 to December 2005) databases. We used the search terms "schizophrenia," "cognition or memory" and "tacrine or donepezil or rivastigmine or galantamine." Studies included were critically analyzed for allocation, blindness, duration and study design, demographic data, and clinical and neuropsychological outcome assessments. We excluded studies that involved patients with psychiatric disorders other than schizophrenia-spectrum or if they involved animals or molecular investigations. We also excluded conference proceeding abstracts with no explicit neuropsychological battery and/or results. RESULTS: Data on ChEI as adjunctive therapy for the cognitive impairments in schizophrenia are sparse and so far derived from small samples and mostly open uncontrolled studies. ChEI's potential in long-term management has barely been documented and remains to be fully explored. CONCLUSION: There is insufficient evidence on whether ChEI should be used for the treatment of cognitive dysfunctions in schizophrenia. Nevertheless, further studies with appropriate trial designs and outcome measures in homogenous schizophrenia populations are warranted.

Cholinesterase Inhibitors↗
PubMed2005

Clinical and radiographic subtypes of vascular cognitive impairment in a clinic-based cohort study.

BACKGROUND AND PURPOSE: There is a need for empirical studies to define criteria for vascular cognitive impairment (VCI) subtypes. In this paper, we report the predictive validity of a subtype classification scheme based on clinical and radiographic features. METHODS: Nine Canadian memory clinics participated in the Consortium to Investigate Vascular Impairment of Cognition. This cohort consisted of 1347 patients, of whom 324 had VCI, and was followed for up to 30 months. RESULTS: Clinical and neuroimaging features defined three subtypes: vascular cognitive impairment, no dementia, (n=97), vascular dementia (n=101) and mixed neurodegenerative/vascular dementia (n=126). Any ischemic lesion on neuroimaging increased the odds (odds ratio=9.31; 95% confidence interval 6.46, 13.39) of a VCI diagnosis. No VCI subtype, however, was associated with a specific neuroimaging abnormality. Compared to those with no cognitive impairment, patients with each VCI subtype had higher rates of death and institutionalization (hazard ratio for combined adverse events=6.08, p<0.001). CONCLUSIONS: Both clinical features and radiographic features help establish a diagnosis of VCI. The outcomes of VCI subtypes, however, are more strongly associated with clinical features than with radiographic ones.

Aged↗
PubMed2005

Efficacy and safety of donepezil in patients with more severe Alzheimer's disease: a subgroup analysis from a randomized, placebo-controlled trial.

BACKGROUND: There have been very limited investigations of cholinesterase inhibitor therapy in more advanced stages of Alzheimer's disease (AD). The efficacy and safety of donepezil were evaluated in post hoc analyses of a subgroup of patients with more severe AD (standardized Mini-Mental State Examination [sMMSE] score 5-12) within a randomized, placebo-controlled trial in moderate to severe AD (MSAD study). Additional analyses examined whether donepezil's treatment effects were consistent across the full range of baseline AD severity studied (sMMSE score 5-17). METHODS: Patients with moderate to severe AD (n = 290) who were living in the community or in assisted living facilities received donepezil or placebo for 24 weeks; n = 145 in the more severe AD subgroup. The primary outcome measure was the Clinician's Interview-Based Impression of Change (CIBIC-plus) with secondary outcomes including the sMMSE, Severe Impairment Battery, Neuropsychiatric Inventory, and Disability Assessment for Dementia. Analysis of Variance and Analysis of Covariance models tested for treatment x disease severity interaction in the full MSAD study sample. RESULTS: CIBIC-plus scores for donepezil patients were significantly improved compared with placebo for each time-point, with a 0.70 mean treatment difference at Week 24 last observation carried forward (LOCF; p = 0.0002). Significant differences favoring donepezil were noted at Week 24 LOCF for all secondary measures. There were no treatment x severity interactions for any of the efficacy measures. CONCLUSIONS: In this analysis, donepezil had significant benefits over placebo on global, cognitive, functional, and behavioral measures in a subgroup of patients with more severe AD. Furthermore, the treatment effects of donepezil were not driven by a particular stratum within the moderate to severe dementia range.

Aged↗