Thursday, June 23, 2011

Protein Analysis Narrows Diagnosis of Alzheimer's Disease

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Ordinarily, Alzheimer’s disease can only be diagnosed after death. Scientists have been searching for biomarkers to diagnose or even predict the illness, with only modest success. Now, German researchers writing in the journal Neurology have measured the concentration of several proteins in cerebrospinal fluid that further characterize Alzheimer’s and differentiate it from other forms of dementia.

Robert Perneczky, M.D., and colleagues from the Technical University Munich collected samples from 58 patients with mild cognitive impairment and followed them for  three years. Patients with mild cognitive impairment who later progressed to having Alzheimer’s disease had significantly higher concentrations of soluble amyloid precursor protein-β (sAPPβ) than similar patients who did not get Alzheimer’s disease or patients with frontotemporal dementia. A combination of sAPPβ, tau (another protein), and age differentiated the mild cognitive impairment patients with Alzheimer’s from those who never got Alzheimer’s, with a sensitivity of 80 percent and a specificity of 81 percent. In addition, a model using the sAPPβ and tau proteins differentiated Alzheimer’s and the frontotemporal dementia groups with a sensitivity of 95 percent and a specificity of 81 percent.

Read more on the role of proteins in Alzheimer’s disease in Psychiatric News at
http://pn.psychiatryonline.org/content/46/9/18.1.full.