The GuidAge study: methodological issues. A 5-year double-blind randomized trial of the efficacy of EGb 761 for prevention of Alzheimer disease in patients over 70 with a memory complaint.
ABSTRACT Preventive approaches in the field of Alzheimer disease (AD) is important but these trials raise many questions. Which protective factor should be studied? What population should be studied? With which principal and secondary criteria? We present here the design of the ongoing GuidAge Study. In the past, several studies suggest that Ginkgo biloba could have a potential benefit effect on cognitive function. The aim of the GuidAge Study is to evaluate the efficacy of 240 mg/d of EGb 761 in the prevention of AD.
GuidAge is a 5-year double-blind randomized trial conducted in France by a private practice/hospital network of general practitioners and hospital practitioners specializing in memory disorders. This study enrolled elderly subjects with spontaneous memory complaint and the primary outcome is the incidence of AD during a 5 years follow-up period. A total of 2854 subjects were enrolled between March 2002 and September 2004. The age of the study population was 76.8 +/- 4.4 with mean MMSE at entry 27.8 +/- 1.7.
The GuidAge study is the largest study carried out in Europe on the prevention of AD. Final results should be available in 2010.
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ABSTRACT: While we may not be able to find a cure for Alzheimer's disease (AD) in the near future, several drugs presently in trials have shown promise as possible modifiers of disease progression. However, we may not be able to demonstrate efficacy due to issues of recruitment, retention, site-to-site variability, and other methodological issues. It is thus incumbent on the scientific community to find solutions to these problems, particularly as the field moves toward preventing illness or treating the disease in its prodromal stages, where these methodological issues will become even more critical. We need to better understand why participants agree or refuse to enter drug trials, and why both primary care physicians and Alzheimer's specialists agree or refuse to involve their patients. We also need to quantify the impact of requiring imaging studies, extensive questionnaires, cognitive testing, and lumbar punctures on recruitment and retention. With these concerns in mind, an international task force meeting of experts from academia and industry in the United States, European Union, and Japan in San Diego, California on November 2, 2011 to focus on recruitment, retention and other methodological issues related to clinical trials for AD. Based on the recommendations of this Task force meeting, this Perspectives article critically reflects on the most critical and timely methodological issues related to recruitment and retention in prevention and therapeutic trials in AD, which are paralleled by a paradigm shift in the diagnostic conceptualization of this disease, as reflected by recently new proposed diagnostic criteria involving preclinical stages of the disease.The Journal of Nutrition Health and Aging 04/2012; 16(4):339-45. · 2.39 Impact Factor
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ABSTRACT: Subjective cognitive complaints (SCCs) are being increasingly recognized as a preclinical phase of dementia. Thus, SCCs may represent a "promising" stage for planning and implementing preventive interventions aimed at reducing the incidence of cognitive disorders. The aim of the present study is to present and discuss the available evidence coming from clinical trials adopting cognitive interventions in individuals with SCCs. A systematic review of literature was conducted to evaluate the available trials testing nonpharmacological cognitive interventions for the prevention of dementia in subjects with SCCs. Six studies were included in the present study. Overall, most interventions showed to objectively improve cognitive performance in subjects with SCCs. A relevant heterogeneity was found concerning their characteristics and feasibility. Conversely, there is a current lack of evidence in the literature about the efficacy of nonpharmacological cognitive interventions for preventing dementia or cognitive impairment.American Journal of Alzheimer s Disease and Other Dementias 07/2013; · 1.52 Impact Factor
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ABSTRACT: Clinical trials in Alzheimer's disease (AD) do not only generate high costs but have also been of little success within recent years. The failure of several large phase III clinical trials on highly promising disease modifying compounds calls for a critical reflection on potential reasons and counter-measures. The recent introduction of new diagnostic criteria of AD and the development and validation of diagnostic and predictive AD biomarkers allows enriching study populations, reducing variance, and improving statistical power of trials while even opening the possibility to reduce total study costs. While CSF or extensive imaging biomarkers might adversely affect retention in clinical trials, their careful application will unlikely reduce adherence. Regulatory authorities are generally supportive of biomarker use in clinical trials but potential consequences of biomarker based patient selection on the generalizability of trial results need careful evaluation.The Journal of Nutrition Health and Aging 04/2012; 16(4):346-8. · 2.39 Impact Factor