Alzheimer's Disease Neuroimaging Initiative Grand Opportunity
Condition: Mild Cognitive Impairment; Alzheimer's Disease
MeSH terms: Alzheimer Disease; Cognitive Dysfunction
Study type: Observational

Summary: 
      The purpose of this study is to build upon the information obtained in the original
      Alzheimer's Disease Neuroimaging Initiative (ADNI1), to examine how brain imaging technology
      can be used with other tests to measure the progression of mild cognitive impairment (MCI)
      and early Alzheimer's disease (AD). ADNI-GO seeks to define and characterize the mildest
      symptomatic phase of AD, referred to in this study as early amnestic MCI (EMCI). This
      information will aid in the early detection of AD, and in measuring the effectiveness of
      treatments in future clinical trials.
    

Detailed description: 
      This project continues the work from ADNI1, the goal of which is to test whether serial
      magnetic resonance imaging (MRI), positron emission tomography (PET), other biological
      markers, and clinical and neuropsychological assessments can be combined to measure the
      progression of mild cognitive impairment (MCI) and early Alzheimer's disease (AD). The goal
      of the study is to determine relationships among the clinical, cognitive, imaging, genetic,
      and biochemical biomarker characteristics of the stage of the AD spectrum that precedes MCI,
      the mildest symptomatic phase of AD, referred to here as EMCI. The ADNI-GO model posits that
      AD begins with amyloid β (Aβ) deposition in the cortex, which leads to synaptic dysfunction,
      neurodegeneration, and cognitive/ functional decline.

      Some of the leading-edge technologies under study are brain-imaging techniques, such as
      positron emission tomography (PET), including FDG-PET (which measures glucose metabolism in
      the brain); PET using a radioactive compound (F-AV-45) that measures brain beta-amyloid; and
      structural MRI. Brain scans are showing scientists how the brain's structure and function
      change as AD starts and progresses. Biomarkers in cerebrospinal fluid are revealing other
      changes that could identify which patients with MCI will develop Alzheimer's. Scientists are
      looking at levels of beta-amyloid and tau in cerebrospinal fluid. (Abnormal amounts of the
      amyloid and tau proteins in the brain are hallmarks of Alzheimer's disease.)

      All participants from ADNI1 who are in the normal and MCI stages will continue to be followed
      in ADNI-GO. The next step is to scan and analyze the brains of people with EMCI; 200 EMCI
      participants will be enrolled to narrow the gap between cognitively normal (CN) and "late MCI
      (LMCI)" participants currently enrolled in ADNI.

      The overall impact of this study will be increased knowledge concerning the sequence and
      timing of events leading to MCI and AD, development of better clinical and imaging/fluid
      biomarker methods for early detection and for monitoring the progression of these conditions,
      and facilitation of clinical trials of treatments to slow disease progression, ultimately
      contributing to the prevention of AD.
    

Observational model: Case-Control
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        community sample
      
Biospecimen description: 
      blood, urine, cerebrospinal fluid
    
Keywords: amyloid; plaques; imaging; early detection; Amnestic MCI; pre-dementia