Alzheimer’s graphic

A new study suggests that proteins in the blood could help predict the development of Alzheimer’s disease before its onset. Specifically, researchers identified 10 proteins that predicted progression from mild cognitive impairment (MCI) to Alzheimer’s disease.

The study involved three multicenter cohorts including elderly adults who were cognitively healthy, or had MCI or Alzheimer’s disease. The researchers initially identified 16 proteins that correlated with disease severity and cognitive decline, but then found the strongest association in the group with MCI, “with a panel of 10 proteins predicting progression to AD (accuracy 87%, sensitivity 85%, and specificity 88%),” reports the study, which was published in Alzheimer’s & Dementia.

The researchers used multiplex bead assays to characterize the proteins and also performed magnetic resonance imaging on 476 subjects to assess various structural brain features such as ventricular volume, hippocampal volume, and entorhinal thickness. Six of the proteins, including clusterin, neuron-specific enolase, and vascular cell adhesion molecule 1, predicted 19.5% of hippocampal volume in subjects with MCI, while seven, including brain-derived neurotrophic factor and plasminogen activator inhibitor-1, predicted 11.9% of hippocampal volume in those who had AD. The researchers also examined the relationship between the proteins and disease severity as measured by cognition at the time of sampling and by the rate of change in cognition.

“Our present findings suggest that we have identified a panel of plasma biomarkers, associated with neuroimaging measures of disease, which may serve as readily accessible markers of early disease severity,” the researchers wrote. “Moreover, we identify a set of 10 protein biomarkers that can prospectively predict disease conversion from MCI to AD within a year of blood sampling. These results are supported by other evidence that plasma proteins can have a role in early disease detection, with inflammatory proteins in particular being identified as possible predictors of conversion from MCI.”

Read more about the study online.