A new study published in the Journal of Alzheimer’s Disease has identified a biomarker in blood that may help predict the development of dementia years before the onset of symptoms.
In the study, researchers measured phosphorylated-tau181 (p-tau181) levels in the blood of 52 US adults who participated in the Framingham Heart Study. The participants had a mean age of about 64 years at the time of measurement. P-tau181 is a marker for neurodegeneration that has previously been associated with cognitive decline. All 52 of the study participants were cognitively unimpaired when their p-tau181 levels were measured. Then, an average of 6.8 years later, the participants underwent brain scans.
An analysis of the brain scans showed that higher levels of p-tau181 in the blood during the initial measurement were associated with more accumulation of ß-amyloid an average of almost 7 years later. ß-amyloid is a protein that is the main component of plaques found in the brains of Alzheimer’s patients, and plaque deposits of ß-amyloid are one of the hallmarks of Alzheimer’s disease pathology. As the study’s lead author noted, the results of this study may help identify individuals who are at a high risk of developing Alzheimer’s disease at a very early stage of its progression.
The Framingham Heart Study which began in 1948, is an ongoing study that aims to identify the common factors and characteristics that contribute to cardiovascular disease. The study has followed cohorts over multiple generations and identified many major risk factors for heart disease. While its original aim was focused on heart disease, it has also helped identify risk factors for several other physiological conditions, including dementia.