Alzheimer’s Disease and Mild Cognitive Impairment: A Review of Etiology, Clinical Diagnosis, and the Involvement of Dendritic Spines

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder affecting a range of cognitive faculties, for which there is currently no treatment, save for ameliorative strategies. This disease primarily affects the elderly, and is the leading cause of dementia among this group. Out of an estimated 5.4 million Americans with AD this year, 5.2 million are over the age of 65. With the amount of people aged 65 and older increasing as the Baby Boomer generation ages, AD will become an increasingly dire burden. As we face this growing issue, research into both its causes and more sensitive and accurate diagnostic tools abounds.1 This research progresses in tandem with efforts to more accurately describe, identify, and understand a prodromal, transitional state between normal cognition and Alzheimer’s dementia called Mild Cognitive Impairment (MCI). MCI comprises a number of sub-types, one of which (amnestic MCI) having a marked association with later progression to frank AD.2 This introduction will offer a summary of these conditions and the research into their etiology, clinical criteria, and improved methods of earlier detection. Emphasis will later be placed on the biology of dendritic spines, including the upstream regulators of their development, and their relation to AD and MCI