Prospects for designating Alzheimer's disease research a national priority

Informing Understandings of Mild Cognitive Impairment for Older Adults: Implications From a Scoping Review

The development of effective interventions for mild cognitive impairment (MCI) in older adults has been limited by extensive variability in the conceptualization and definition of MCI, its subtypes, and relevant diagnostic criteria within the neurocultural, pharmaceutical, and gerontological communities. A scoping review was conducted to explore the conceptual development of MCI and identify the resulting ethical, political, and technological implications for the care of older adults with MCI. A comprehensive search was conducted between January and April 2013 to identify English-language peer-reviewed articles published between 1999 and 2013. Our analysis revealed that the MCI conceptual debate remains unresolved, the response to ethical issues is contentious, the policy response is limited, and one-dimensional and technological interventions are scarce. Reflections on the conceptual, ethical, and policy responses in conjunction with the identification of the needs of older adults diagnosed with MCI highlight significant opportunities for technological interventions to effectively reposition MCI in the aging care discourse.

Epigenomics of Alzheimer's disease

Alzheimer's disease (AD) is a large and growing public health problem. It is characterized by the accumulation of amyloid β peptides and abnormally phosphorylated tau proteins that are associated with cognitive decline and dementia. Much has been learned about the genomics of AD from linkage analyses and, more recently, genome-wide association studies. Several but not all aspects of the genomic landscape are involved in amyloid β metabolism. The moderate concordance of disease among twins suggests other factors, potentially epigenomic factors, are related to AD. We are at the earliest stages of examining the relation of the epigenome to the clinical and pathologic phenotypes that characterize AD. Our literature review suggests that there is some evidence of age-related changes in human brain methylation. Unfortunately, studies of AD have been relatively small with limited coverage of methylation sites and microRNA, let alone other epigenomic marks. We are in the midst of 2 large studies of human brains including coverage of more than 420,000 autosomal cytosine-guanine dinucleotides with the Illumina Infinium HumanMethylation450 BeadArray, and histone acetylation with chromatin immunoprecipitation sequencing. We present descriptive data to help inform other researchers what to expect from these approaches to better design and power their studies. We then discuss future directions to inform on the epigenomic architecture of AD.

Using genetics to enable studies on the prevention of Alzheimer's disease

Curing Alzheimer's disease (AD) remains an elusive goal; indeed, it may even prove to be impossible, given the nature of the disease. Although modulating disease progression is an attractive target and will alleviate the burden of the most severe stages, this strategy will not reduce the prevalence of the disease itself. Preventing or (as described in this article) delaying the onset of cognitive impairment and AD will provide the greatest benefit to individuals and society by pushing the onset of disease into the later years of life. Because of the high variability in the age of onset of the disease, AD prevention studies that do not stratify participants by age-dependent disease risk will be operationally challenging, being large in size and of long duration. We present a composite genetic biomarker to stratify disease risk so as to facilitate clinical studies in high-risk populations. In addition, we discuss the rationale for the use of pioglitazone to delay the onset of AD in individuals at high risk.