A Prognostic Alzheimer's Disease Blood Test in the Symptom-Free Stage

A study in Alzheimer's Research and Therapy applied a blood test to predict the risk of Alzheimer's disease in people who were clinically diagnosed as not having the disorder, but who perceived themselves as cognitively impaired, reports ScienceDaily . The investigators identified all 22 subjects at the start of the study who developed Alzheimer's dementia and clinical symptoms within six years. The test also projected those at very low risk who would develop Alzheimer's dementia within six years. Blood samples were analyzed using an immuno-infrared sensor that detects misfolding of the amyloid-beta (Aß) peptide — a biomarker for Alzheimer's — and found it in the 22 subjects who developed the disease in the following six years. In subjects exhibiting mild misfolding, conversion to clinical Alzheimer took 3.4 years on average compared to 2.2 years in subjects with severe Aß misfolding. The statistical model determined that Subjective Cognitive Declined (SCD) subjects with mild misfolding have an 11-fold higher risk of developing clinical Alzheimer's in the following six years, while SCD subjects with severe misfolding have a 19-fold higher risk. "Through the plasma biomarker panel, we can monitor disease progression over 14 years, beginning in the asymptomatic state with misfolding of Aß and subsequent plaque deposition of Aß42 in the brain associated with the first cognitive impairments," said Julia Stockmann at Ruhr-Universität Bochum.