ADNI: Alzheimer's Disease Neuroimaging Initiative

This study will test whether serial magnetic resonance imaging (MRI), positron emission tomography (PET), other biological markers, and clinical and neuropsychological assessment can be combined to measure the progression of mild cognitive impairment (MCI) and early Alzheimer's disease (AD). The information obtained by studying changes in the brain images of MCI and AD patients and healthy individuals, as well as other assessment tools, will be used to determine the best methods for measuring treatment effects in patients with MCI and AD. Approximately 800 participants, ranging in age from 55 to 90, will be recruited for the study: 400 patients with MCI, 200 with early AD, and 200 normal controls. Patients with MCI and normal controls will be followed for 3 years, and those with AD will be followed for 2 years. At 6-month intervals, all participants will be seen in person or contacted by telephone. All participants will undergo repeated scanning and blood and urine biomarkers will be collected at the time of each scan. All patients will be asked if they are willing to undergo lumbar puncture at baseline and year one, with the goal of a minimum of 20% and as many as 50% of each group providing CSF (cerebrospinal fluid) samples for analysis and storage for future analyses. NOTE: Beginning in Spring 2007 a subset of the ADNI participants will be offered the opportunity to participate in a supplemental study. The PIB (Pittsburgh Compound B) study provides imaging of amyloid plaque burden. PIB PET scans will be conducted in 24 control, 48 MCI, and 24 AD participants at approximately 16 ADNI PET sites. For entering participants with no previous PET FDG scans, controls and MCI participants will be scanned with PIB at entry (baseline), 12, 24, and 36 months, and AD participants will be scanned with PIB at entry (baseline), 12, and 24 months. For participants who have undergone previous (baseline and 6 month) PET FDG scans, controls and MCI participants will be scanned with PIB at 12, 24, and 36 months, and AD participants will be scanned with PIB at 12 and 24 months.