Atrophy accelerates with conversion from mild cognitive impairment to Alzheimer disease

Abstract

If the current rates of growth of the senior population and prevalence of Alzheimer disease (AD) continue, the number of individuals worldwide affected by this disabling disease will double from 24.3 to 42.3 million by 2020.1 Given the devastating impact of AD on patient, family, community, and society, considerable efforts are underway to unravel its pathophysiologic mechanisms, with the aim of developing safe and effective disease-modifying therapies. Such therapies will probably be most efficacious in the early symptomatic or ideally pre-symptomatic stages of the disease.2 An accurate diagnosis of AD in the early symptomatic stage is extremely challenging despite the development of useful clinical constructs like mild cognitive impairment (MCI), which enables the identification of individuals who may be in an early clinical phase of AD. Future diagnostic approaches toward early symptomatic and presymptomatic AD will almost certainly hinge upon biomarkers. In fact, new diagnostic criteria were recently proposed that operationalize the pre-dementia diagnosis of AD and include imaging and CSF biomarkers as supportive evidence.3 Beyond their use in diagnostics, imaging and other biomarkers will likely serve important roles in monitoring effects of …