Summary Interventions that have even quite modest effects at the individual level could drastically reduce the future burden of dementia associated with Alzheimer's disease at the population level. ...In the past three decades, both pharmacological and lifestyle interventions have been studied for the prevention of cognitive decline or dementia in randomised controlled trials of individuals mostly aged older than 50–55 years with or without risk factors for Alzheimer's disease. Several trials testing the effects of physical activity, cognitive training, or antihypertensive interventions showed some evidence of efficacy on a primary cognitive endpoint. However, most of these trials had short follow-up periods, and further evidence is needed to confirm effectiveness and establish the optimum design or dose of interventions and ideal target populations. Important innovations in ongoing trials include the development of multidomain interventions, and the use of biomarker or genetic inclusion criteria. Challenges include the use of adaptive trial designs, the development of standardised, sensitive outcome measures, and the need for interventions that can be implemented in resource-poor settings.
Verubecestat, an orally administered inhibitor of BACE-1, reduces amyloid concentration in the cerebrospinal fluid. In a randomized, 78-week trial involving patients with mild or moderate Alzheimer’s ...disease, the drug did not slow cognitive decline as compared with placebo.
In two phase 3 placebo-controlled, randomized trials in 1012 and 1040 patients with mild-to-moderate Alzheimer's disease, solanezumab, a humanized monoclonal antibody that preferentially binds ...soluble forms of amyloid, did not improve cognition or functional status.
Alzheimer's disease is associated with the accumulation of aggregated amyloid-beta (Aβ) peptide in the cerebral cortex and hippocampus. One approach to reducing brain amyloid involves increasing the clearance of Aβ by means of prolonged treatment with monoclonal antibodies directed against this peptide. In preclinical studies, a murine antibody that targeted the central domain of Aβ and was selective for soluble forms slowed Aβ deposition in a transgenic mouse model
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; in another transgenic murine model, Aβ–antibody complexes were present in the cerebrospinal fluid (CSF) and plasma, and behavioral deficits were reversed without a decrease in amyloid plaques, as assessed by . . .
In a randomized trial, patients with brain amyloid deposition but no dementia who received a β-site amyloid precursor protein–cleaving enzyme 1 inhibitor had no benefit with respect to clinical ...outcomes and worsening on some measures of cognition and daily function.
In this placebo-controlled trial, the γ-secretase inhibitor semagacestat did not improve cognitive status in patients with Alzheimer's disease and was associated with more adverse events than ...placebo, including skin cancers and infections.
Alzheimer's disease begins decades before the appearance of clinical symptoms, with the deposition of aggregated amyloid-beta (Aβ) peptide plaques in the cortex and hippocampus. This protein is cleaved from the amyloid precursor protein (APP) by the sequential action of β- and γ-secretases, producing fragments that include Aβ1-40 and Aβ1-42. Since the accumulation of aggregated Aβ is associated with disease progression, both β-secretase and γ-secretase represent potential therapeutic targets. Multiple small molecules can inhibit γ-secretase in vitro,
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–
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but Notch and other transmembrane proteins are also substrates for γ-secretase,
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–
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and studies have raised concern that the inhibition of γ-secretase could . . .
Alzheimer is a severe disease and new therapies are really needed. After the development of symptomatic drugs 30 years ago, our objective is to develop disease modifying treatment using anti-amyloid ...therapies over an 18-month period. First we targeted mild to moderate AD, probably at a too severe stage. Later we targeted mild dementia and when biomarkers became available, we realized that almost 30% of our patients had no amyloid deposit and probably did not have Alzheimer's disease (1, 2). Then, we started to target early and mild AD defined with amyloid deposit using CSF and PET biomarkers, but our drug dosage was probably not high enough (3, 4). And finaly with the Aducanumab studies we observed some effects with high doses (5, 6). On June 7, 2021 for the first time, the FDA approved a disease modifying drug, Aducanumab. After decades of research, it is good news for patients, and those dedicated to the field, but it is also a challenging time with some frustrations and some hope. In the present JNHA editorial we will review the FDA statement and the consequences for geriatricians and primary care physicians, from frustration to new hope.
Evidence for the Domains Supporting the Construct of Intrinsic Capacity Cesari, Matteo; Araujo de Carvalho, Islene; Amuthavalli Thiyagarajan, Jotheeswaran ...
The journals of gerontology. Series A, Biological sciences and medical sciences,
11/2018, Volume:
73, Issue:
12
Journal Article, Web Resource
Peer reviewed
Open access
Healthy ageing can be defined as "the process of developing and maintaining the functional ability that enables wellbeing in older age". Functional ability (i.e., the health-related attributes that ...enable people to be and to do what they have reason to value) is determined by intrinsic capacity (i.e., the composite of all the physical and mental capacities of an individual), the environment (i.e., all the factors in the extrinsic world that form the context of an individual's life), and the interactions between the two. This innovative model recently proposed by the World Health Organization has the potential to substantially modify the way in which clinical practice is currently conducted, shifting from disease-centered toward function-centered paradigms. By overcoming the multiple limitations affecting the construct of disease, this novel framework may allow the worldwide dissemination of a more proactive and function-based approach toward achieving optimal health status. In order to facilitate the translation of the current theoretical model into practice, it is important to identify the inner nature of its constituting constructs. In this article, we consider intrinsic capacity. Using the International Classification of Functioning, Disability and Health (ICF) framework as background and taking into account available evidence, five domains (i.e., locomotion, vitality, cognition, psychological, sensory) are identified as pivotal for capturing the individual's intrinsic capacity (and therefore also reserves) and, through this, pave the way for its objective measurement.
In a randomized trial, solanezumab, a humanized monoclonal antibody against soluble amyloid, did not slow cognitive decline over a period of 80 weeks in patients with mild Alzheimer’s disease and ...with PET or CSF biomarkers of amyloid-related disease.
The prevention of dementias, such as Alzheimer's disease (AD), is a growing public health concern, due to a lack of effective curative treatment options and a rising global prevalence. Various ...potential risk or preventive factors have been suggested by epidemiological research, including modifiable lifestyle factors such as diet. Current epidemiological data are in favour of a protective role of certain micronutrients (B vitamins related to homocysteine metabolism, the anti‐oxidant vitamins C and E, flavonoids, polyunsatured omega‐3 fatty acids, vitamin D) and macronutrients (fish) in the prevention of cognitive decline and dementia/AD. Some factors have been targeted by interventions tested in randomized controlled trials (RCTs), but many of the results are conflicting with observational evidence. Epidemiological analysis of the relations between nutrient consumption and cognitive decline is complex and it is highly unlikely that a single component plays a major role. In addition, since multiple factors across the life course influence brain function in late life, multidomain interventions might be more promising in the prevention of cognitive decline and dementia/AD. Designing such trials remains very challenging for researchers. The main objective of this paper is to review the epidemiologic data linking potential protective factors to cognitive decline or dementia/AD, focusing particularly on the roles of adiposity, caloric restriction, micro (group B vitamins related to homocysteine metabolism, the anti‐oxidant vitamins C and E, flavonoids, polyunsatured omega‐3 fatty acids, vitamin D) and macronutrients (fish). Limitations of the current data, divergence with results of interventional prevention studies and challenges for future research are discussed.
Introduction
This study investigated the diagnostic and disease‐monitoring potential of plasma biomarkers in mild cognitive impairment (MCI) and Alzheimer's disease (AD) dementia and cognitively ...unimpaired (CU) individuals.
Methods
Plasma was analyzed using Simoa assays from 99 CU, 107 MCI, and 103 AD dementia participants.
Results
Phosphorylated‐tau181 (P‐tau181), neurofilament light, amyloid‐β (Aβ42/40), Total‐tau and Glial fibrillary acidic protein were altered in AD dementia but P‐tau181 significantly outperformed all biomarkers in differentiating AD dementia from CU (area under the curve AUC = 0.91). P‐tau181 was increased in MCI converters compared to non‐converters. Higher P‐tau181 was associated with steeper cognitive decline and gray matter loss in temporal regions. Longitudinal change of P‐tau181 was strongly associated with gray matter loss in the full sample and with Aβ measures in CU individuals.
Discussion
P‐tau181 detected AD at MCI and dementia stages and was strongly associated with cognitive decline and gray matter loss. These findings highlight the potential value of plasma P‐tau181 as a non‐invasive and cost‐effective diagnostic and prognostic biomarker in AD.