MRI and neuropsychological tests best predict Alzheimer's disease in old patients

Investigators from the University of Amsterdam, Netherlands, have shown that in most elderly patients invasive and expensive techniques, i.e. lumbar puncture and PET scan, are not useful to establish the diagnosis of Alzheimer's disease. They arrived at this conclusion after analysis of data from the Alzheimer's Disease Neuroimaging Initiative (ADNI), a large collaborative research project of medical centers in the USA and Canada. The Dutch researchers divided the ADNI sample into two halves, a younger (<75 y) and an older half (>74 y). They showed that the CSF biomarkers (amyloid and tau), and FDG- PET, are informative in the younger but not in the older patients. In the older patients MRI scans and neuropsychological tests appeared to convey useful information, but CSF biomarkers and FDG-PET did not. The latter two techniques are informative only in younger patients.